Federal Register, Volume 77 Issue 243 (Tuesday, December 18, 2012)

[Federal Register Volume 77, Number 243 (Tuesday, December 18, 2012)]
[Proposed Rules]
[Pages 74923-74985]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-30117]

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Vol. 77

Tuesday,

No. 243

December 18, 2012

Part II

Environmental Protection Agency

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40 CFR Part 131

Water Quality Standards for the State of Florida's Estuaries, Coastal
Waters, and South Florida Inland Flowing Waters; Water Quality
Standards for the State of Florida's Streams and Downstream Protection
Values for Lakes: Remanded Provisions; Proposed Rules

Federal Register / Vol. 77, No. 243 / Tuesday, December 18, 2012 /
Proposed Rules

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 131

[EPA-HQ-OW-2010-0222; FRL-9759-3]
RIN 2040-AF21

Water Quality Standards for the State of Florida's Estuaries,
Coastal Waters, and South Florida Inland Flowing Waters

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The U.S. Environmental Protection Agency (EPA or Agency) is
proposing numeric water quality criteria to protect ecological systems,
aquatic life, and human health from nitrogen and phosphorus pollution
in estuaries and coastal waters within the State of Florida not covered
by EPA-approved State rulemaking, and south Florida inland flowing
waters. These proposed criteria apply to Florida waters that are
designated as Class I, Class II, or Class III waters and they are
intended to protect these designated uses as well as implement for the
purposes of the Clean Water Act the State's narrative nutrient
provision at Subsection 62-302.530(47)(b), Florida Administrative Code
(F.A.C.), which provides that ``[i]n no case shall nutrient
concentrations of a body of water be altered so as to cause an
imbalance in natural populations of aquatic flora or fauna.''

DATES: Comments must be received on or before February 19, 2013.
Because of EPA's obligation to sign a notice of final rulemaking on or
before September 30, 2013 under Consent Decree, the Agency regrets that
it will be unable to grant any requests to extend this deadline.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-OW-
2010-0222, by one of the following methods:
1. www.regulations.gov: Follow the on-line instructions for
submitting comments.
2. Email: ow-docket@epa.gov.
3. Mail to: Water Docket, U.S. Environmental Protection Agency,
Mail code: 2822T, 1200 Pennsylvania Avenue NW, Washington, DC 20460,
Attention: Docket ID No. EPA-HQ-OW-2010-0222.
4. Hand Delivery: EPA Docket Center, EPA West Room 3334, 1301
Constitution Avenue NW, Washington, DC 20004, Attention Docket ID No.
EPA-HQ-OW-2010-0222. Such deliveries are only accepted during the
Docket's normal hours of operation, and special arrangements should be
made for deliveries of boxed information.
Instructions: Direct your comments to Docket ID No. EPA-HQ-OW-2010-
0222. EPA's policy is that all comments received will be included in
the public docket without change and may be made available online at
www.regulations.gov, including any personal information provided,
unless the comment includes information claimed to be Confidential
Business Information (CBI) or other information whose disclosure is
restricted by statute. Do not submit information that you consider to
be CBI or otherwise protected through www.regulations.gov or email. The
www.regulations.gov Web site is an ``anonymous access'' system, which
means EPA will not know your identity or contact information unless you
provide it in the body of your comment. If you submit an electronic
comment, EPA recommends that you include your name and other contact
information in the body of your comment and with any disk or CD-ROM you
submit. If EPA cannot read your comment due to technical difficulties
and cannot contact you for clarification, EPA may not be able to
consider your comment. Electronic files should avoid the use of special
characters, any form of encryption, and be free of any defects or
viruses. For additional information about EPA's public docket visit the
EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.
Docket: All documents in the docket are listed in the
www.regulations.gov index. Although listed in the index, some
information is not publicly available, e.g., CBI or other information
whose disclosure is restricted by statute. Certain other material, such
as copyrighted material, will be publicly available only in hard copy.
Publicly available docket materials are available either electronically
in www.regulations.gov or in hard copy at a docket facility. The Office
of Water (OW) Docket Center is open from 8:30 a.m. until 4:30 p.m.,
Monday through Friday, excluding legal holidays. The OW Docket Center
telephone number is (202) 566-2426, and the Docket address is OW
Docket, EPA West, Room 3334, 1301 Constitution Avenue NW., Washington,
DC 20004. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m.,
Monday through Friday, excluding legal holidays. The telephone number
for the Public Reading Room is (202) 566-1744.

FOR FURTHER INFORMATION CONTACT: Erica Fleisig, U.S. EPA Headquarters,
Office of Water, Mailcode: 4305T, 1200 Pennsylvania Avenue NW,
Washington, DC 20460; telephone number: (202) 566-1057; email address:
fleisig.erica@epa.gov.

SUPPLEMENTARY INFORMATION: This supplementary information section is
organized as follows:

Table of Contents

I. General Information
A. Executive Summary
B. Which water bodies are affected by this rule?
C. What entities may be affected by this rule?
D. What should I consider as I prepare my comments for EPA?
E. How can I get copies of this document and other related
information?
II. Background
A. Nitrogen and Phosphorus Pollution
B. Statutory and Regulatory Background
C. Water Quality Criteria
D. EPA Determination Regarding Florida and Consent Decree
E. EPA's Rulemaking and Subsequent Litigation
F. Florida Adoption of Numeric Nutrient Criteria and EPA
Approval
III. Proposed Numeric Criteria for Florida's Estuaries, Coastal
Waters, and South Florida Inland Flowing Waters
A. General Information and Approaches
B. Proposed Numeric Criteria for Estuaries
C. Proposed Numeric Criteria for Coastal Waters
D. Proposed Numeric Criteria for South Florida Inland Flowing
Waters
E. Applicability of Criteria When Final
IV. Under what conditions will EPA either not finalize or withdraw
these Federal standards?
V. Alternative Regulatory Approaches and Implementation Mechanisms
A. Designating Uses
B. Variances
C. Site-Specific Alternative Criteria
D. Compliance Schedules
VI. Economic Analysis
A. Incrementally Impaired Waters
B. Point Source Costs
C. Non-Point Source Costs
D. Governmental Costs
E. Summary of Costs
F. Benefits
VII. Statutory and Executive Order Reviews
A. Executive Orders 12866 (Regulatory Planning and Review) and
13563 (Improving Regulation and Regulatory Review)
B. Paperwork Reduction Act
C. Regulatory Flexibility Act
D. Unfunded Mandates Reform Act
E. Executive Order 13132 (Federalism)
F. Executive Order 13175 (Consultation and Coordination With
Indian Tribal Governments)
G. Executive Order 13045 (Protection of Children From
Environmental Health and Safety Risks)
H. Executive Order 13211 (Actions That Significantly Affect
Energy Supply, Distribution, or Use)
I. National Technology Transfer Advancement Act of 1995
J. Executive Order 12898 (Federal Actions To Address
Environmental Justice in

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Minority Populations and Low-Income Populations)

I. General Information

A. Executive Summary

1. Purpose of the Regulatory Action
The primary purpose of this rule is to propose numeric water
quality criteria to protect ecological systems, aquatic life, and human
health within the State of Florida from nitrogen and phosphorus
pollution. The criteria proposed in this rule apply to certain
estuaries and coastal waters within the State of Florida and south
Florida inland flowing waters (e.g., rivers, streams, canals),\1\ with
the exception of waters within the lands of the Miccosukee and Seminole
Tribes, the Everglades Agricultural Area (EAA), and the Everglades
Protection Area (EvPA).\2\
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\1\ EPA has distinguished south Florida inland flowing waters as
waters in the South Florida Nutrient Watershed Region (SFNWR). The
SFNWR was defined previously in EPA's final rule for lakes and
flowing waters as the area south of Lake Okeechobee, the
Caloosahatchee River watershed (including Estero Bay) to the west of
Lake Okeechobee, and the St. Lucie watershed to the east of Lake
Okeechobee.
\2\ FL Statute Section 373.4592 (1994) subsection (2)
Definitions: (e) ``Everglades Agricultural Area'' or ``EAA'' means
the Everglades Agricultural Area, which are those lands described in
FL Statute Section 373.4592 (1994) subsection (15). FL Statute
Section 373.4592 (1994) subsection (2) Definitions: (h) ``Everglades
Protection Area'' means Water Conservation Areas 1 (which includes
the Arthur R. Marshall Loxahatchee National Wildlife Refuge), 2A,
2B, 3A, and 3B, and the Everglades National Park.
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The criteria support implementation of pollution control programs
authorized under the Clean Water Act (CWA). As part of a comprehensive
program to restore and protect the Nation's waters, Section 303(c) of
the CWA directs states to adopt water quality standards for their
navigable waters. CWA Section 303(c)(2)(A) and EPA's implementing
regulations at 40 CFR 131 require that state water quality standards
include the designated use (e.g. public water supply, propagation of
fish and wildlife, recreational purposes) and criteria that protect
those uses. Criteria may be numeric or narrative in form, but
consistent with EPA regulations at 40 CFR 131.11(a)(1), such criteria
``must be based on sound scientific rationale and must contain
sufficient parameters or constituents to protect the designated use.''
EPA regulations at 40 CFR 131.10(b) also provide that ``[i]n
designating uses of a water body and the appropriate criteria for those
uses, the state shall take into consideration the water quality
standards of downstream waters and ensure that its water quality
standards provide for the attainment and maintenance of the water
quality standards of downstream waters.'' The CWA requires that any new
or revised water quality standards developed by states be submitted to
EPA for review and approval or disapproval, and authorizes the EPA
Administrator to determine, even in the absence of a state submission,
that a new or revised standard is needed to meet CWA requirements.
Florida is known for its abundant and aesthetically beautiful
natural resources, particularly its aquatic resources, which are very
important to Florida's economy. Florida's coastal and estuarine waters
play an especially important part in sustaining the environment and the
economy in the State. For example, Florida's saltwater sport fishing
industry contributes over $5 billion to the State's economy and more
than 54,000 jobs annually; the State's commercial saltwater fishing
industry contributes over $1 billion and more than 10,000 jobs
annually.\3\ In 2007, nearly 11.3 million residents and 46.3 million
visitors participated in recreational saltwater beach activities in
Florida. Nearly 3.5 million residents and approximately 1.4 million
visitors used saltwater boat ramps, over 4.2 million residents and
about 3 million visitors participated in saltwater non-boat fishing,
and over 2.6 million residents and almost 1 million visitors
participated in canoeing and kayaking.\4\
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\3\ FFWCC. 2011. The economic impact of saltwater fishing in
Florida. Florida Fish and Wildlife Conservation Commission. http://myfwc.com/conservation/value/saltwater-fishing. Accessed December
2011.
\4\ FDEP. 2008. Chapter 5--Outdoor Recreation Demand and Need.
In Outdoor Recreation in Florida, 2008: Florida's Comprehensive
Outdoor Recreation Plan, Final Draft. Florida Department of
Environmental Protection, Division of Recreation and Parks,
Tallahassee, FL. http://www.dep.state.fl.us/parks/planning/forms/SCORP5.pdf. Accessed December 2011.
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However, nitrogen and phosphorus pollution has contributed to
serious water quality degradation affecting these coastal and estuarine
resources in the State of Florida, as well as other Florida waters. In
the most recent Florida Department of Environmental Protection (FDEP)
water quality assessment report, the Integrated Water Quality
Assessment for Florida: 2012 305(b) Report and 303(d) List Update, FDEP
describes widespread water quality impairment in Florida due to
nitrogen and phosphorus pollution. FDEP's 2012 report identifies
approximately 754 square miles (482,560 acres) of estuaries (about 14
percent of assessed estuarine area) and 102 square miles (65,280 acres)
of coastal waters (about 1.6 percent of assessed coastal waters) as
impaired by nutrients. In addition, the same report indicates that
1,108 miles of rivers and streams (about 8 percent of assessed river
and stream miles) and 107 square miles (68,480 acres) of lakes (about 5
percent of assessed lake square miles) are impaired due to nutrient
pollution.\5\
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\5\ FDEP. 2012. Integrated Water Quality Assessment for Florida:
2012 305(b) Report and 303(d) List Update. (May 2012). Florida
Department of Environmental Protection, Division of Environmental
Assessment and Restoration, Tallahassee, FL. http://www.dep.state.fl.us/water/docs/2012_integrated_report.pdf.
Accessed August 2012.
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On January 14, 2009, EPA determined under CWA section 303(c)(4)(B)
that new or revised water quality standards (WQS) in the form of
numeric nutrient water quality criteria are necessary to protect the
designated uses that Florida has set for its Class I, Class II, and
Class III waters. Subsequently, EPA entered into a Consent Decree with
Florida Wildlife Federation, Sierra Club, Conservancy of Southwest
Florida, Environmental Confederation of Southwest Florida, and St.
Johns Riverkeeper, effective on December 30, 2009, which established a
schedule for EPA to propose and promulgate numeric nutrient criteria
for Florida's lakes, flowing waters, estuaries, and coastal waters. The
Consent Decree also provided that if Florida submitted and EPA approved
numeric nutrient criteria for any relevant waterbodies before the dates
outlined in the schedule, EPA would no longer be obligated to propose
or promulgate criteria for those waterbodies.
On June 13, 2012, FDEP submitted new and revised WQS for review by
the EPA pursuant to section 303(c) of the CWA. These new and revised
WQS are set out primarily in Rule 62-302 of the F.A.C. [Surface Water
Quality Standards]. FDEP also submitted amendments to Rule 62-303,
F.A.C. [Identification of Impaired Surface Waters], which sets out
Florida's methodology for assessing whether waters are attaining State
WQS. On November 30, 2012, EPA approved the provisions of these rules
submitted for review that constitute new or revised WQS (hereafter
referred to as the ``newly-approved State WQS'').
Among the newly-approved State WQS are numeric criteria for
nutrients that apply to a set of estuaries and coastal marine waters in
Florida. Specifically, these newly-approved State WQS apply to
Clearwater Harbor/St. Joseph Sound, Tampa Bay, Sarasota Bay, Charlotte
Harbor/Estero Bay, Clam Bay, Tidal Cocohatchee River/Ten Thousand
Islands, Florida Bay, Florida

[[Page 74926]]

Keys, and Biscayne Bay.\6\ Under the Consent Decree, EPA is relieved of
its obligation to propose numeric criteria for these waters.
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\6\ Clam Bay, Tidal Cocohatchee River/Ten Thousand Islands,
Florida Bay, Florida Keys, and Biscayne Bay are collectively
referred to in this proposed rule as ``south Florida marine
waters,'' as these are the predominantly marine waters downstream of
the South Florida Nutrient Watershed Region.
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Finally, as described in EPA's November 30, 2012 approval of
Florida's new or revised WQS, while EPA believes that the provisions
addressing downstream protection will provide for quantitative
approaches to ensure the attainment and maintenance of downstream
waters consistent with 40 CFR 131.10(b), the provisions themselves do
not consist of numeric values. Because EPA is currently subject to a
Consent Decree deadline to sign a rule proposing numeric downstream
protection values (DPVs) for Florida by November 30, 2012, EPA is
proposing numeric DPVs to comply with the Consent Decree. However, EPA
has amended its January 2009 determination to specify that numeric
criteria for downstream protection are not necessary and that
quantitative approaches designed to ensure the attainment and
maintenance of downstream water quality standards, such as those
established by Florida, are sufficient to meet CWA requirements. As
such, EPA will ask the court to modify the Consent Decree consistent
with the Agency's amended determination, i.e., to not require EPA to
promulgate numeric DPVs for Florida. Accordingly, EPA approved the
State's downstream protection provisions subject to the district court
modifying the Consent Decree to not require EPA to promulgate numeric
DPVs for Florida. If the district court agrees to so modify the Consent
Decree, EPA will not promulgate numeric DPVs for Florida. However, if
the district court declines to so modify the Consent Decree, EPA would
intend to promulgate numeric DPVs for Florida and would also expect to
revisit its November 30, 2012 approval of the State Rule's downstream
protection provisions to modify or withdraw its approval. Therefore,
EPA has also reserved its authority to do so in its approval document.
A full description of all of EPA's recent actions on Florida
numeric nutrient criteria and related implications for EPA's own rules
can be found at http://water.epa.gov/lawsregs/rulesregs/florida_index.cfm.
EPA is proposing these numeric criteria in accordance with the
terms of the January 14, 2009 determination, December 2009 Consent
Decree, and subsequent revisions to that Consent Decree that require
the EPA Administrator to sign this proposal by November 30, 2012
(discussed in more detail in Section II.D). EPA believes that the
proposed criteria in this rule will assure protection of Florida's
existing designated uses and are based on sound and substantial
scientific data and analyses.
2. Summary of the Major Provisions of the Regulatory Action
To develop these proposed numeric nutrient criteria for Florida's
estuaries, coastal waters, and south Florida inland flowing waters, the
Agency conducted a detailed scientific analysis of the substantial
amount of water quality data available from Florida's extensive
monitoring data set.
EPA concluded that an approach using relevant biological endpoints
and multiple lines of evidence including stressor-response analyses and
mechanistic modeling was a strong and scientifically sound approach for
deriving numeric nutrient criteria for estuaries, in the form of total
nitrogen (TN), total phosphorus (TP) and chlorophyll a concentrations.
EPA's methodology and the resulting proposed estuarine numeric nutrient
criteria are presented in more detail in Section III.B of this notice
of proposed rulemaking.
For coastal waters on the Atlantic and Gulf coasts of Florida, EPA
is proposing to use a reference condition-based approach. EPA chose to
use satellite remote sensing in all coastal areas of Florida except the
Big Bend Coastal region. Using this approach, EPA developed chlorophyll
a criteria from satellite remote sensing imagery and field data to
calibrate the satellite remote sensing imagery. In the Big Bend Coastal
region of Florida,\7\ where satellite remote sensing predictions of
chlorophyll a were not possible due to reflectance that interferes with
the remote sensing imagery in that area, EPA used mechanistic and
statistical models to determine TN, TP, and chlorophyll a criteria for
these coastal waters.\8\ EPA's methodology and results for its proposed
coastal criteria are presented in more detail in Sections III.B and
III.C.
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\7\ This area includes waters offshore of Apalachicola Bay,
Alligator Harbor, Ochlockonee Bay, Big Bend/Apalachee Bay, Suwannee
River, and Springs Coast.
\8\ EPA derived TN and TP criteria for coastal waters in the Big
Bend Coastal region because mechanistic models were used in these
areas.
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EPA is proposing numeric nutrient criteria to ensure the attainment
and maintenance of the water quality standards in downstream estuaries
and south Florida marine waters pursuant to the provisions of 40 CFR
131.10(b). EPA examined a variety of modeling techniques and data to
assess whether waters entering an estuary protect the water quality
standards within the estuary. Accordingly, EPA is proposing an approach
to derive TN and TP criteria expressed as downstream protection values
(DPVs) at the points where inland flowing waters flow into estuaries,
or marine waters in south Florida (referred to as `pour points'). These
proposed DPVs apply to all flowing waters, including south Florida
inland flowing waters (with the exception of waters within the lands of
the Miccosukee and Seminole Tribes, EAA, and EvPA), that flow directly
into estuaries or south Florida marine waters. EPA's proposed approach
for deriving DPVs at the pour points involves an evaluation of water
quality in the downstream estuary, water quality conditions at the pour
point, and selecting a method to derive the DPV values based on
available data. The proposed approaches for deriving DPVs in flowing
waters are presented in more detail in Sections III.B and III.D.
Finally, EPA is proposing to extend the approach finalized in 40
CFR 131.43(e) \9\ to allow development of Site-Specific Alternative
Criteria (SSAC) for estuaries, coastal waters, and south Florida inland
flowing waters. EPA's rationale for extending these SSAC provisions is
discussed in more detail in Section V.C.
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\9\ 40 CFR 131.43(e) authorizes the derivation of Federal Site-
Specific Alternative Criteria (SSAC) after EPA review and approval
of applicant submissions of scientifically defensible criteria that
meet the requirements of CWA section 303(c) and EPA's implementing
regulations at 40 CFR 131.
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EPA has incorporated sound science, local expertise, and
substantial Florida-specific data throughout the development of these
proposed numeric TN, TP, and chlorophyll a criteria. EPA relied upon
peer-reviewed criteria development methodologies,\10\ relevant
biological endpoints, and a substantial

[[Page 74927]]

body of scientific analysis provided to EPA by FDEP, as well as other
federal, State, and local partners such as the National Park Service;
National Oceanic and Atmospheric Administration (NOAA); U.S. Geological
Survey (USGS); Tampa Bay, Indian River Lagoon, Sarasota Bay and
Charlotte Harbor National Estuary Programs; St. Johns River and South
Florida Water Management Districts; and Florida International
University.
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\10\ USEPA. 2000a. Nutrient Criteria Technical Guidance Manual:
Lakes and Reservoirs. EPA-822-B-00-001. U.S. Environmental
Protection Agency, Office of Water, Washington, DC.
USEPA. 2000b. Nutrient Criteria Technical Guidance Manual:
Rivers and Streams. EPA-822-B-00-002. U.S. Environmental Protection
Agency, Office of Water, Washington, DC.
USEPA. 2001. Nutrient Criteria Technical Guidance Manual:
Estuarine and Coastal Marine Waters. EPA-822-B-01-003. U.S.
Environmental Protection Agency, Office of Water, Washington, DC.
USEPA. 2010. Using Stressor-Response Relationships to Derive
Numeric Nutrient Criteria. EPA-820-S-10-001. U.S. Environmental
Protection Agency, Office of Water, Washington, DC.
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EPA sought feedback on the scientific defensibility of the
approaches outlined in this proposed rule through a Science Advisory
Board (SAB) review.\11\ The SAB assembled a group of eighteen expert
panelists to review EPA's Methods and Approaches for Deriving Numeric
Criteria for Nitrogen/Phosphorus Pollution in Florida's Estuaries,
Coastal Waters, and Southern Inland Flowing Waters.\12\ The SAB
recommendations \13\ strengthened the scientific basis of these
proposed numeric nutrient criteria. A number of key interest groups
presented their comments and views on the underlying science as part of
the SAB review process. In addition, EPA met with several groups of
stakeholders with local technical expertise to discuss potential
approaches for deriving scientifically defensible numeric nutrient
criteria.
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\11\ USEPA-SAB. 2011. Review of EPA's draft Approaches for
Deriving Numeric Nutrient Criteria for Florida's Estuaries, Coastal
Waters, and Southern Inland Flowing Waters. EPA-SAB-11-010. U.S.
Environmental Protection Agency, Science Advisory Board, Washington,
DC.
\12\ USEPA. 2010. Methods and Approaches for Deriving Numeric
Criteria for Nitrogen/Phosphorus Pollution in Florida's Estuaries,
Coastal Waters, and Southern Inland Flowing Waters. U.S.
Environmental Protection Agency, Office of Water, Washington, DC.
\13\ USEPA-SAB. 2011. Review of EPA's draft Approaches for
Deriving Numeric Nutrient Criteria for Florida's Estuaries, Coastal
Waters, and Southern Inland Flowing Waters. EPA-SAB-11-010. U.S.
Environmental Protection Agency, Science Advisory Board, Washington,
DC.
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3. Costs and Benefits
For the reasons presented in this notice, this is not an
economically significant regulatory action under Executive Order 12866.
Under the CWA, EPA's promulgation of WQS establishes standards that the
State of Florida implements through the National Pollutant Discharge
Elimination System (NPDES) permit process for point source dischargers
and may also result in new or revised requirements for nitrogen and
phosphorus pollution treatment controls on other sources (e.g.,
agriculture, urban runoff, and septic systems) through the development
of Total Maximum Daily Loads (TMDLs) and Basin Management Action Plans
(BMAPs). As a result of this action, the State of Florida will need to
ensure that permits it issues and Waste Load Allocations (WLAs) issued
under TMDLs and BMAPs include any limitations on discharges and other
sources necessary to comply with the standards established in the final
rule. In doing so, the State will have considerable discretion and a
number of choices associated with permit writing (e.g., relating to
compliance schedules, variances, etc.) and flexibilities built into the
TMDL and BMAP process for WLA assignment. While Florida's
implementation of the rule may ultimately result in new or revised
permit conditions for some dischargers and WLA requirements for control
on other sources, EPA's action, by itself, does not establish any
requirements directly applicable to regulated entities or other sources
of nitrogen and phosphorus pollution. Additionally, Florida already has
an existing narrative water quality criterion \14\ which requires that
nutrients not be present in estuaries and coastal waters in Florida or
in south Florida inland flowing waters in concentrations that cause an
imbalance in natural populations of flora and fauna. The proposed
criteria in this rule are consistent with and serve to implement the
State's existing narrative nutrient provision.
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\14\ Subsection 62-302.530(47)(b), Florida Administrative Code
(F.A.C.), provides that ``[i]n no case shall nutrient concentrations
of a body of water be altered so as to cause an imbalance in natural
populations of aquatic flora or fauna.''
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Although the proposed rule does not establish any requirements
directly applicable to regulated entities or other sources of nutrient
pollution, EPA developed an economic analysis to provide information on
potential costs and benefits that may be associated with the State
implementation requirements that may be necessary to ensure attainment
of WQS. EPA conducted an analysis to estimate both the increase in the
number of impaired waters that may be identified as a result of the
proposed rule and the annual cost of CWA pollution control actions
likely to be implemented by the State of Florida to assure attainment
of applicable State water quality designated uses for these waters. It
is important to note that the costs and benefits of pollution controls
needed to attain water quality standards for nutrients for waters
already identified as impaired by the State (including waters with
TMDLs in place and without TMDLs in place) are not included in EPA
estimates of the cost of the rule. EPA believes that these costs and
benefits would be incurred in the absence of the current proposed rule
and are therefore part of the baseline against which the costs and
benefits of this rule are measured. EPA's analysis is fully described
in the document entitled Economic Analysis of Proposed Water Quality
Standards for the State of Florida's Estuaries, Coastal Waters, and
South Florida Inland Flowing Waters (hereinafter referred to as the
Economic Analysis), which can be found in the docket and record for
this proposed rule. The final conclusion of this assessment is that the
incremental costs associated with the proposed rule range between
$239.0 million and $632.4 million per year (2010 dollars) and total
monetized benefits may be in the range from $39.0 to $53.4 million
annually. EPA's analysis describes additional benefits that could not
be monetized. EPA has provided estimates of the annual costs and
benefits; these exceed the $100 million threshold that defines an
economically significant rule under section 3(f) of Executive Order
12866. However, EPA cautions that these estimates cannot be used to
determine that this rule is economically significant. The direct effect
of this rule is to provide Florida with a numeric articulation of its
current narrative articulation of nutrients criteria, without affecting
the resulting level of protection offered by the criteria. The
estimates of costs and benefits here are indirect estimates (costs and
benefits associated with controls for waters that would immediately be
judged to be impaired due to numeric criteria) of the direct effects of
this proposed rule (decreasing the time to implement TMDLs on impaired
waters), and the relationship these indirect estimates bear to the true
costs and benefits cannot be determined.

B. Which water bodies are affected by this rule?

EPA's proposed rule applies to estuaries and coastal marine waters
that have been classified by Florida as Class II (Shellfish Propagation
or Harvesting) or Class III (Recreation, Propagation and Maintenance of
a Healthy, Well-Balanced Population of Fish and Wildlife), including
tidal creeks and marine lakes, but excluding the estuarine and marine
waters contained in Florida's newly-approved State WQS. This proposed
rule also applies to south Florida inland flowing waters that have been
classified by Florida as Class I (Potable Water Supplies) or Class III
water bodies pursuant to Section 62-302.400, F.A.C., excluding wetlands
(e.g. sloughs in south Florida) and flowing waters within the lands of
the Miccosukee and Seminole Tribes, EvPA,

[[Page 74928]]

or EAA.\15\ Pursuant to Subsection 62-302.400(4), F.A.C., ``Class I,
II, and III surface waters share water quality criteria established to
protect fish consumption, recreation and the propagation and
maintenance of a healthy, well-balanced population of fish and
wildlife.'' \16\ Florida currently has a narrative nutrient criterion
at Subsection 62-302.530(47)(b), F.A.C.\17\ established to protect
these three uses and EPA is numerically interpreting Florida's
narrative criterion for the purpose of protecting the Class I, II, and
III surface waters for the purposes of the CWA in this proposed
rulemaking.
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\15\ In this rule, EPA is interpreting the existing State
narrative criterion under Subsection 62-302.530(47)(b), F.A.C. That
criterion applies to Florida waters classified as Class I (Potable
Water Supplies), Class II (Shellfish Propagation or Harvesting), and
Class III Marine and Fresh (Recreation, Propagation and Maintenance
of a Healthy, Well-Balanced Population of Fish and Wildlife). EPA is
not aware of any marine waters that Florida has classified as Class
I potable water supply. Therefore, for purposes of this rule, EPA is
interpreting Subsection 62-302.530(47)(b), F.A.C. to protect fish
consumption, recreation, and the propagation and maintenance of a
healthy, well-balanced population of fish and wildlife in Florida's
Class II and III estuarine and coastal waters.
\16\ Class I waters also include an applicable nitrate limit of
10 mg/L and nitrite limit of 1 mg/L for the protection of human
health in drinking water supplies. The nitrate limit applies at the
entry point to the distribution system (i.e., after any treatment);
see Section 62-550, F.A.C., for additional details.
\17\ ``[i]n no case shall nutrient concentrations of a body of
water be altered so as to cause an imbalance in natural populations
of aquatic flora or fauna''
---------------------------------------------------------------------------

EPA is not proposing to change any of Florida's water body
classifications with this regulation. The proposed criteria in this
regulation would only apply to water bodies that are currently
classified by Florida as Class I, II, or III and not to water bodies
with other classifications such as Class III limited waters \18\ for
which use attainability analyses (UAAs) and SSACs for nutrients have
been established, or Class IV canals in Florida's agricultural areas.
---------------------------------------------------------------------------

\18\ Class III limited waters include waters that support fish
consumption; recreation or limited recreation; and/or propagation
and maintenance of a limited population of fish and wildlife; see
Chapter 62-302.400(1) F.A.C. for more details.
---------------------------------------------------------------------------

EPA is defining estuary to be consistent with Florida's definition
of estuary in Section 62-303.200, F.A.C., where ``estuary'' shall mean
``predominantly marine regions of interaction between rivers and
nearshore ocean waters, where tidal action and river flow mix fresh and
salt water.'' Such areas include bays, mouths of rivers, and lagoons
that have been classified as Class II (Shellfish Propagation or
Harvesting) or Class III (Recreation, Propagation and Maintenance of a
Healthy, Well-Balanced Population of Fish and Wildlife) water bodies
pursuant to Section 62-302.400, F.A.C., excluding wetlands.
EPA is defining coastal waters based on Florida's definitions of
open coastal waters and open ocean waters, taking into account that CWA
jurisdiction extends to three nautical miles from shore.\19\ EPA's
definition of ``coastal waters'' is all marine waters that have been
classified as Class II (Shellfish Propagation or Harvesting) or Class
III (Recreation, Propagation and Maintenance of a Healthy, Well-
Balanced Population of Fish and Wildlife) water bodies pursuant to
Section 62-302.400, F.A.C., extending to three nautical miles from
shore that are not classified as estuaries. EPA's proposed rule defines
``marine waters'' to mean surface waters in which the chloride
concentration at the surface is greater than or equal to 1,500
milligrams per liter (mg/L).
---------------------------------------------------------------------------

\19\ While CWA jurisdiction, and therefore EPA's proposed
criteria, extend only to three nautical miles from shore (CWA
section 502(8)), Florida State jurisdiction extends beyond three
nautical miles. Florida's seaward boundary in Gulf of Mexico waters
is 3 marine leagues (9 nautical miles) and in Atlantic waters is 3
nautical miles (Submerged Lands Act of 1953. http://www.boem.gov/uploadedFiles/submergedLA.pdf; United States v. Florida, 363 U.S.
121 (1960)). Florida defines open coastal waters as ``all gulf or
ocean waters that are not classified as estuaries or open ocean
waters.'' Open ocean waters consist of ``all surface waters
extending seaward from the most seaward natural 90-foot (15-fathom)
isobath'' (Subsection 62-303.200, F.A.C.).
---------------------------------------------------------------------------

EPA is defining tidal creeks as relatively small coastal
tributaries with variable salinity that lie at the transition zone
between terrestrial uplands and the open estuary. For another subset of
marine waters, marine lakes, EPA is proposing to use the definition of
``marine waters'' and the definition of lakes included previously in
Water Quality Standards for the State of Florida's Lakes and Flowing
Waters (40 CFR 131.43) to define a marine lake as a slow-moving or
standing body of marine water that occupies an inland basin that is not
a stream, spring, or wetland.
EPA previously defined ``flowing waters'' in Water Quality
Standards for the State of Florida's Lakes and Flowing Waters (40 CFR
131.43). A flowing water is defined as ``a free-flowing, predominantly
fresh surface water in a defined channel, and includes rivers, creeks,
branches, canals, freshwater sloughs, and other similar water bodies.''
Consistent with EPA's definition in 40 CFR 131.43, EPA defines
``canal'' for this proposed rule to mean a trench, the bottom of which
is normally covered by water with the upper edges of its two sides
normally above water. Also as defined in 40 CFR 131.43, ``predominantly
fresh waters'' means surface waters in which the chloride concentration
at the surface is less than 1,500 mg/L. EPA is not proposing criteria
for areas currently managed by the State as wetlands (such as sloughs
in south Florida), which are outside the scope of this rulemaking.\20\
---------------------------------------------------------------------------

\20\ FDEP. 2001. Chapter 2: Ecological Description. In:
Everglades Phosphorus Criterion Technical Support Document. Part
III: WCA-3/ENP. Florida Department of Environmental Protection,
Everglades Technical Support Section. http://www.dep.state.fl.us/water/wqssp/.everglades/docs/pctsd/IIIChapter.2.pdf. Accessed
January, 10, 2011.
Doherty, S.J., C.R. Lane, and M.T. Brown. 2000. Proposed
Classification for Biological Assessment of Florida Inland
Freshwater Wetlands. Report to the Florida Department of
Environmental Protection. Contract No. WM68 (Development of a
Biological Approach for Assessing Wetland Function and Integrity).
Center for Wetlands, University of Florida, Gainesville, FL.
Ogden, J.C. 2005. Everglades ridge and slough conceptual
ecological model. Wetlands 25(4):810-820.
---------------------------------------------------------------------------

C. What entities may be affected by this rule?

Citizens concerned with water quality in Florida may be interested
in this rulemaking. Entities discharging nitrogen or phosphorus to
estuaries, coastal waters, and flowing waters in Florida could be
indirectly affected by this rulemaking because water quality standards
are used in determining National Pollutant Discharge Elimination System
(NPDES) permit limits. Examples of categories and entities that may
ultimately be affected are listed in the following table:

------------------------------------------------------------------------
Examples of potentially
Category affected entities
------------------------------------------------------------------------
Industry............................... Industries discharging
pollutants to estuaries,
coastal waters and flowing
waters in the State of
Florida.
Municipalities......................... Publicly-owned treatment works
discharging pollutants to
estuaries, coastal waters and
flowing waters in the State of
Florida.
Stormwater Management Districts........ Entities responsible for
managing stormwater runoff in
the State of Florida.
------------------------------------------------------------------------

This table is not intended to be exhaustive, but rather provides a
guide for entities that may be indirectly affected by this action.
Other types of entities not listed in the table, such as non-point
source contributors to nitrogen and phosphorus pollution in Florida's
waters, may be affected through implementation of Florida's water
quality standards program (e.g., through Basin Management Action Plans
(BMAPs)). Any parties or entities

[[Page 74929]]

conducting activities within Florida watersheds covered by this
proposed rule, or who depend upon or contribute to the water quality of
the estuaries, coastal waters, and flowing waters of Florida, may be
affected by this rule. To determine whether your facility or activities
may be affected by this action, you should examine this proposed rule.
If you have questions regarding the applicability of this action to a
particular entity, consult the person listed in the preceding FOR
FURTHER INFORMATION CONTACT section.

D. What should I consider as I prepare my comments for EPA?

1. Submitting CBI. Do not submit confidential business information
(CBI) to EPA through http://www.regulations.gov or email. Clearly mark
the part or all of the information that you claim to be CBI. For CBI
information in a disk or CD-ROM that you mail to EPA, mark the outside
of the disk or CD-ROM as CBI and then identify electronically within
the disk or CD-ROM the specific information that is claimed as CBI. In
addition to one complete version of the comment that includes
information claimed as CBI, a copy of the comment that does not contain
the information claimed as CBI must be submitted for inclusion in the
public docket. Information so marked will not be disclosed except in
accordance with procedures set forth in 40 CFR part 2.
2. Tips for Preparing Your Comments. When submitting comments,
remember to:
Identify the rulemaking by docket number and other
identifying information (subject heading, Federal Register date, and
page number).
Follow directions--The agency may ask you to respond to
specific questions or organize comments by referencing a Code of
Federal Regulations (CFR) part or section number.
Explain why you agree or disagree; suggest alternatives
and substitute language for your requested changes.
Describe any assumptions and provide any technical
information and/or data that you used.
If you estimate potential costs or burdens, explain how
you arrived at your estimate in sufficient detail to allow for it to be
reproduced.
Provide specific examples to illustrate your concerns, and
suggest alternatives.
Make sure to submit your comments by the comment period
deadline identified.
Commenters who submitted public comments or scientific information
on the portions of EPA's January 26, 2010 proposed Water Quality
Standards for the State of Florida's Lakes and Flowing Waters (75 FR
4173) that are addressed in this proposal should reconsider their
previous comments in light of the new information presented in this
proposal and must re-submit their comments during the public comment
period for this rulemaking to receive EPA response.

E. How can I get copies of this document and other related information?

1. Docket. EPA has established an official public docket for this
action under Docket Id. No. EPA-HQ-OW-2010-0222. The official public
docket consists of the document specifically referenced in this action,
any public comments received, and other information related to this
action. Although a part of the official docket, the public docket does
not include CBI or other information whose disclosure is restricted by
statute. The official public docket is the collection of materials that
is available for public viewing at the OW Docket, EPA West, Room 3334,
1301 Constitution Ave. NW., Washington, DC 20004. This Docket Facility
is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding
legal holidays. The Docket telephone number is 202-566-2426. A
reasonable fee will be charged for copies.
2. Electronic Access. You may access this Federal Register document
electronically through the EPA Internet under the ``Federal Register''
listings at http://www.epa.gov/fedrgstr/. An electronic version of the
public docket is available through EPA's electronic public docket and
comment system, EPA Dockets. You may use EPA Dockets at http://www.regulations.gov to view public comments, access the index listing
of the contents of the official public docket, and to access those
documents in the public docket that are available electronically. For
additional information about EPA's public docket, visit the EPA Docket
Center homepage at http://www.epa.gov/epahome/dockets.htm. Although not
all docket materials may be available electronically, you may still
access any of the publicly available docket materials through the
Docket Facility identified in Section I.E(1).

II. Background

A. Nitrogen and Phosphorus Pollution

1. What is nitrogen and phosphorus pollution?
a. Overview of Nitrogen and Phosphorus Pollution
Excess loading of nitrogen and phosphorus to surface water bodies
and groundwater is one of the leading causes of water quality
impairments in the United States.\21\ The problem extends to both fresh
and marine waters,\22\ leading to over 15,000 nutrient pollution-
related impairments in 49 states across the country--a figure that may
substantially understate the problem as many waters have yet to be
assessed.\23\ Estuaries and coastal waters are especially vulnerable to
nitrogen and phosphorus pollution because they are the ultimate
receiving waters for most major watersheds transporting nitrogen and
phosphorus loadings from multiple upstream sources.\24\
---------------------------------------------------------------------------

\21\ Dubrovsky, N.M., K.R. Burow, G.M. Clark, J.M. Gronberg,
P.A. Hamilton, K.J. Hitt, D.K. Mueller, M.D. Munn, B.T. Nolan, L.J.
Puckett, M.G. Rupert, T.M. Short, NE. Spahr, L.A. Sprague, and W.G.
Wilber. 2010. The Quality of our Nation's waters--Nutrients in the
Nation's Streams and Groundwater, 1992-2004. Circular 1350. U.S.
Geological Survey, National Water Quality Assessment Program,
Reston, VA. http://water.usgs.gov/nawqa/nutrients/pubs/circ1350.
Accessed December 2011.
\22\ Smith, V.H., S.B. Joye, and R.W. Howarth. 2006.
Eutrophication of freshwater and coastal marine ecosystems.
Limnology and Oceanography 51(1, part 2):351-355.
Schindler, D.W. 2006. Recent advances in the understanding and
management of eutrophication. Limnology and Oceanography 51(1,
part2):356-363.
\23\ Nationally, only 27% of rivers and streams and less than
50% of lakes, reservoirs, and ponds have been assessed for
impairment (USEPA. 2011. National Summary of State Information. U.S.
Environmental Protection Agency, Watershed Assessment, Tracking &
Environmental Results. http://iaspub.epa.gov/waters10/attains_nation_cy.control. Accessed January 2012).
\24\ Bricker, S., B. Longstaff, W. Dennison, A. Jones, K.
Boicourt, C. Wicks, and J. Woerner. 2007. Effects of Nutrient
Enrichment in the Nation's Estuaries: A Decade of Change. NOAA
Coastal Ocean Program Decision Analysis Series No. 26. National
Centers for Coastal Ocean Science, Silver Spring, MD. http://ccma.nos.noaa.gov/publications/eutroupdate/Accessed January 2012.
National Research Council. 2000. Clean Coastal Waters:
Understanding and Reducing the Effects of Nutrient Pollution. Report
prepared by the Ocean Study Board and Water Science and Technology
Board, Commission on Geosciences, Environment and Resources,
National Resource Council, Washington, DC.
---------------------------------------------------------------------------

The problem of nitrogen and phosphorus pollution is not new. Over
forty years ago, a 1969 report by the National Academy of Sciences \25\
noted that ``[m]an's activities, which introduce excess nutrients,
along with other

[[Page 74930]]

pollutants, into lakes, streams, and estuaries, are causing significant
changes in aquatic environments. The excess nutrients greatly
accelerate the process of eutrophication. The pollution problem is
critical because of increased population, industrial growth,
intensification of agricultural production, river-basin development,
recreational use of waters, and domestic and industrial exploitation of
shore properties. Accelerated eutrophication causes changes in plant
and animal life--changes that often interfere with use of water,
detract from natural beauty, and reduce property values.'' A 2000
report by the National Research Council \26\ concluded that ``* * *
scientists, coastal managers, and public decision-makers have come to
recognize that coastal ecosystems suffer a number of environmental
problems that can, at times, be attributed to the introduction of
excess nutrients from upstream watersheds. The problems are caused by a
complex chain of events and vary from site to site, but the fundamental
driving force is the accumulation of nitrogen and phosphorus in fresh
water on its way to the sea.''
---------------------------------------------------------------------------

\25\ National Academy of Sciences. 1969. Eutrophication: Causes,
Consequences, Correctives. National Academy of Sciences, Washington,
DC.
\26\ National Research Council. 2000. Clean Coastal Waters:
Understanding and Reducing the Effects of Nutrient Pollution. Report
prepared by the Ocean Study Board and Water Science and Technology
Board, Commission on Geosciences, Environment and Resources,
National Resource Council, Washington, DC.
---------------------------------------------------------------------------

Florida has long struggled with nutrient pollution impacts to its
surface and ground waters. Florida's flat topography makes Florida
particularly susceptible to nitrogen and phosphorus pollution because
water moves more slowly over the landscape, allowing time for nitrogen
and phosphorus pollution to accumulate in water bodies and cause
eutrophication. Florida's high rainfall levels contribute to increased
run-off, and higher temperatures and sunlight contribute to
eutrophication when excess nutrients are available.\27\
---------------------------------------------------------------------------

\27\ Perry, W.B. 2008. Everglades restoration and water quality
challenges in south Florida. Ecotoxicology 17:569-578.
---------------------------------------------------------------------------

In FDEP's 2012 Integrated Water Quality Assessment for Florida:
2012 305(b) Report and 303(d) List Update, nutrient pollution is ranked
as the fifth major cause of estuary impairments by impaired square
miles \28\ and the fifth major cause of impairments in coastal
waters.\29\ FDEP documents nutrient pollution impairments in 754 square
miles (482,560 acres) of estuaries (about 14 percent of the estuarine
area assessed by Florida) and 102 square miles (65,280 acres) of
coastal waters (about 1.6 percent of the assessed coastal waters).\30\
---------------------------------------------------------------------------

\28\ First, second, third, and fourth major causes of estuary
impairments by impaired square miles are mercury in fish, DO,
bacteria in shellfish, and fecal coliform, respectively.
\29\ FDEP. 2012. Integrated Water Quality Assessment for
Florida: 2012 305(b) Report and 303(d) List Update. (May 2012).
Florida Department of Environmental Protection, Division of
Environmental Assessment and Restoration, Tallahassee, FL. http://www.dep.state.fl.us/water/docs/2012_integrated_report.pdf.
Accessed August 2012.
\30\ FDEP. 2012. Integrated Water Quality Assessment for
Florida: 2012 305(b) Report and 303(d) List Update. (May 2012).
Florida Department of Environmental Protection, Division of
Environmental Assessment and Restoration, Tallahassee, FL. http://www.dep.state.fl.us/water/docs/2012_integrated_report.pdf.
Accessed August 2012.
---------------------------------------------------------------------------

FDEP noted in its 2008 Integrated Water Quality Assessment for
Florida: 2008 305(b) Report and 303(d) List Update that nitrogen and
phosphorus pollution poses several challenges in Florida. FDEP stated,
``The close connection between surface and groundwater, in combination
with the pressures of continued population growth, accompanying
development, and extensive agricultural operations, present Florida
with a unique set of challenges for managing both water quality and
quantity in the future. After trending downward for 20 years, beginning
in 2000 phosphorus levels again began moving upward, likely due to the
cumulative impacts of non-point source pollution associated with
increased population and development. Increasing pollution from urban
stormwater and agricultural activities is having other significant
effects.'' \31\
---------------------------------------------------------------------------

\31\ FDEP. 2008. Integrated Water Quality Assessment for
Florida: 2008 305(b) Report and 303(d) List Update. Florida
Department of Environmental Protection, Division of Environmental
Assessment and Restoration, Tallahassee, FL. http://www.dep.state.fl.us/water/docs/2008_Integrated_Report.pdf.
Accessed July 2011.
---------------------------------------------------------------------------

To better understand the nitrogen and phosphorus pollution problem
in Florida, EPA looked at trends in the data Florida uses to create its
Integrated Water Quality Reports,\32\ and found increasing
concentrations of nitrogen and phosphorus compounds in Florida waters
over the 12 year period from 1996-2008. Florida's Impaired Waters Rule
(IWR) data indicate that levels of total nitrogen have increased
approximately 20 percent from a state-wide average of 1.06 mg/L in 1996
to 1.27 mg/L in 2008 and average state-wide total phosphorus levels
have increased approximately 40 percent from an average of 0.108 mg/L
in 1996 to 0.151 mg/L in 2008.
---------------------------------------------------------------------------

\32\ IWR Run 40. Updated through February 2010.
---------------------------------------------------------------------------

On a national scale, the primary sources of nitrogen and phosphorus
pollution can be grouped into five major categories: (1) Urban and
suburban stormwater runoff--sources associated with residential and
commercial land use and development; (2) municipal and industrial
wastewater discharges; (3) row crop agriculture and fertilizer use; (4)
livestock production and manure management practices; and (5)
atmospheric deposition resulting from nitrogen oxide emissions from
fossil fuel combustion and ammonia emissions from row crop agriculture
and livestock production. These sources contribute loadings of
anthropogenic nitrogen and phosphorus to surface and groundwaters, and
may cause harmful impacts to aquatic ecosystems and imbalances in the
natural populations of aquatic flora and fauna.\33\
---------------------------------------------------------------------------

\33\ State-EPA Nutrient Innovations Task Group. 2009. An Urgent
Call to Action: Report of the State-EPA Nutrient Innovations Task
Group. http://water.epa.gov/scitech/swguidance/standards/criteria/nutrients/upload/2009_08_27_criteria_nutrient_nitgreport.pdf
Accessed May 2012.
---------------------------------------------------------------------------

In general, the major sources of nitrogen and phosphorus pollution
in Florida estuarine and coastal waters are the same as those found at
the national scale: urban and suburban stormwater runoff, wastewater
discharges, row crop agriculture, livestock production, and atmospheric
deposition. As is the case with much of the southern United States,
Florida's population continues to grow, with Florida among the top ten
fastest growing states.\34\ Florida's population growth is concentrated
in major cities and along the coast. As of 2005, Florida's highest
population density was along its eastern coast; there has also been
significant population expansion along the western coast from Tampa to
the south. As populations grow, the increased nitrogen and phosphorus
pollution resulting from increased urban stormwater runoff, municipal
wastewater discharges, air deposition, and agricultural livestock
activities and row-crop runoff can place increased stress on all
ecosystems.
---------------------------------------------------------------------------

\34\ U.S. Census Bureau. 2011. Population Distribution and
Change: 2000 to 2010. http://www.census.gov/prod/cen2010/briefs/c2010br-01.pdf. Accessed July 2011.
---------------------------------------------------------------------------

In nearly half of the estuaries examined for this rulemaking, urban
or stormwater runoff is a major contributor of nitrogen and phosphorus
pollution. For example, a report issued in 2010 by the Sarasota Bay
Estuary Program indicates that in Sarasota Bay, nutrients are primarily
transported to the estuary by stormwater runoff, which is the
predominant source in all segments of the estuary (42-60 percent of the
total nitrogen load).\35\ Similarly, according to

[[Page 74931]]

the Tampa Bay Estuary Program, the largest source of nitrogen to Tampa
Bay is also runoff (63 percent of total nitrogen loadings to Tampa Bay
from 1999-2003).\36\ Impervious land cover is a large driver of
stormwater volume. In 2005, one study estimated that 7 percent of
Florida's area had total impervious area greater than 20 percent, and
of that, a quarter of that land had total impervious area greater than
40 percent. As Florida's population grows, it is likely that the
resulting expansion of impervious cover will cause increased harmful
impacts on water quality in coastal areas, wetlands, and other aquatic
ecosystems.\37\
---------------------------------------------------------------------------

\35\ SBEP. 2010. Numeric Nutrient Criteria for Sarasota Bay.
Prepared for the Sarasota Bay Estuary Program by Janicki
Environmental, Inc. http://www.sarasotabay.org/documents/SBEP-NNC-Final-Report.pdf. Accessed August 2011.
\36\ TBEP. No date. About the Tampa Bay Estuary Program, State
of the Bay: Water and Sediment Quality. Tampa Bay Estuary Program.
http://www.tbep.org/tbep/stateofthebay/waterquality.html. Accessed
January 2012.
\37\ Exum, L.R., S.L. Bird, J. Harrison, and C.A. Perkins. 2005.
Estimating and Projecting Impervious Cover in the Southeastern
United States. EPA/600/R-05/061. U.S. Environmental Protection
Agency, Office of Research and Development, Washington, DC.
---------------------------------------------------------------------------

Wastewater is also a significant contributor of nitrogen and
phosphorus pollution. In Florida, there are 443 domestic (not including
septic systems) and industrial wastewater dischargers with individual
NPDES permits.\38\ Of those facilities, 198 are classified as domestic
(municipal) wastewater facilities, which treat sanitary wastewater or
sewage from homes, businesses, and institutions. The other 245
facilities are classified as industrial wastewater facilities. About
one third of Florida's population uses on-site sewage treatment and
disposal (septic tanks) to treat wastewater.\39\
---------------------------------------------------------------------------

\38\ Facilities with NPDES permits either discharge to surface
waters or ground waters, using methods that include land
application, beneficial reuse of reclaimed water, and deep well
injection. USEPA. 2011. Permit Compliance System Database. U.S.
Environmental Protection Agency. http://www.epa.gov/enviro/facts/pcs/customized.html. Accessed June 2011.
There are also 34,508 dischargers covered under generic or
general permits, which FDEP regulates based on categories of
wastewater facilities or activities that involve the same or similar
types of operations or wastes.
\39\ FDEP. 2011. General Facts and Statistics about Wastewater
in Florida. Florida Department of Environmental Protection. http://www.dep.state.fl.us/water/wastewater/facts.htm. Accessed January
2012.
---------------------------------------------------------------------------

In Florida, fewer than a quarter of individually permitted domestic
and industrial facilities are authorized to discharge to surface
waters. The remaining permittees are authorized to discharge solely to
groundwater through land-application, beneficial reuse of reclaimed
water, or deep well injection. Domestic wastewater treatment facilities
permitted by FDEP produce over 1.5 billion gallons of treated effluent
and reclaimed water per day, with a total treatment capacity of over
2.5 billion gallons per day. Eighteen percent of domestic wastewater
treatment facilities have treatment capacities greater than 500,000
gallons per day, whereas 73 percent of domestic wastewater treatment
facilities have capacities less than 100,000 gallons per day.\40\
---------------------------------------------------------------------------

\40\ FDEP. 2011. Wastewater Program. Florida Department of
Environmental Protection. http://www.dep.state.fl.us/water/wastewater/index.htm Accessed January 2012.
---------------------------------------------------------------------------

Wastewater has been cited as contributing to negative impacts on
water quality in some areas. On the east coast of Florida, septic
systems contribute an estimated 1.5 million pounds of nitrogen per year
to Florida's Indian River Lagoon.\41\ There have been some successes in
reducing the impact of wastewater on marine waters. In Tampa Bay,
wastewater treatment plants were one of the major sources of nitrogen
prior to the institution of tertiary nitrogen removal. This treatment
has contributed to an improvement in Tampa Bay's water quality.\42\
---------------------------------------------------------------------------

\41\ USEPA. 2003. EPA Voluntary National Guidelines for
Management of Onsite and Clustered (Decentralized) Wastewater
Treatment Systems. EPA-832-B-03-001. U.S. Environmental Protection
Agency, Office of Water, Washington, DC. http://www.epa.gov/owm/septic/pubs/septic_guidelines.pdf. Accessed August 2011.
\42\ Johansson, J.O.R., and H.S. Greening. 2000. Seagrass
Restoration in Tampa Bay: A Resource-based Approach to Estuarine
Management. Chapter 20 In: Seagrasses: Monitoring, Ecology,
Physiology, and Management, ed. S.A. Bortone, pp. 279-293. CRC
Press, Boca Raton, FL.
---------------------------------------------------------------------------

There have been a number of studies examining the sources of
nitrogen and phosphorus pollution in waters across Florida. One area of
study is Biscayne Bay, located on the southeast coast of Florida,
adjacent to Miami. Nutrient pollution in the Bay comes from a number of
key sources that vary geographically: stormwater runoff from urban
areas, discharges from the Black Point Landfill and Sewage Treatment
Plant, agricultural runoff from canals in the South Dade agricultural
basin, and contaminated ground water.\43\ In the northern section of
the Bay, there are inputs from five canals, a landfill, and urban
runoff. The southern section of the Bay has a greater contribution from
agricultural sources.\44\ In one study, researchers found that canals
conveying waters from agricultural and urban areas contributed 88
percent and 66 percent of the Bay's total dissolved inorganic nitrogen
and total phosphorus loads, respectively.\45\
---------------------------------------------------------------------------

\43\ Caccia, V.G., and J.N. Boyer. 2007. A nutrient loading
budget for Biscayne Bay, Florida. Marine Pollution Bulletin
54(7):994-1008.
Caccia, V.G., and J.N. Boyer. 2005. Spatial patterning of water
quality in Biscayne Bay, Florida as a function of land use and water
management. Marine Pollution Bulletin 50(11):1416-1429.
\44\ Caccia, V.G., and J.N. Boyer. 2005. Spatial patterning of
water quality in Biscayne Bay, Florida as a function of land use and
water management. Marine Pollution Bulletin 50(11):1416-1429.
\45\ Caccia, V.G., and J.N. Boyer. 2007. A nutrient loading
budget for Biscayne Bay, Florida. Marine Pollution Bulletin
54(7):994-1008.
---------------------------------------------------------------------------

b. Adverse Impacts of Nitrogen and Phosphorus Pollution on Aquatic Life
Nitrogen and phosphorus pollution in surface and ground waters
degrade water quality and negatively impact aquatic life through
processes associated with eutrophication.\46\ Eutrophication is a
predictable, well-understood, and widely-documented biological process
by which anthropogenic nitrogen and phosphorus pollution results in
increased growth of algae (plankton and periphyton).\47\
---------------------------------------------------------------------------

\46\ Eutrophication is the process by which a water body becomes
enriched with organic material, which is formed by primary
productivity (i.e., photosynthetic activity) and can be stimulated
to harmful levels by the anthropogenic introduction of high
concentrations of nutrients--particularly nitrogen and phosphorus
(National Research Council. 2000. Clean Coastal Waters:
Understanding and Reducing the Effects of Nutrient Pollution. Report
prepared by the Ocean Study Board and Water Science and Technology
Board, Commission on Geosciences, Environment and Resources,
National Resource Council, Washington, DC. See also Nixon. SW. 1995.
Coastal marine eutrophication: A definition, social causes, and
future concerns. Ophelia 41:199-219.)
\47\ Cambridge, M.L., J.R. How, P.S. Lavery, and M.A.
Vanderklift. 2007. Retrospective analysis of epiphyte assemblages in
relation to seagrass loss in a eutrophic coastal embayment. Marine
Ecology Progress Series 346:97-107.
Frankovich, T.A., and J.W. Fourqurean. 1997. Seagrass epiphyte
loads along a nutrient availability gradient, Florida Bay, USA.
Marine Ecology Progress Series 159:37-50.
Peterson, B.J., T.A. Frankovich, and J.C. Zieman. 2007. Response
of seagrass epiphyte loading to field manipulations of
fertilization, gastropod grazing and leaf turnover rates. Journal of
Experimental Marine Biology and Ecology 349(1):61-72.
Howarth, R., D. Anderson, J. Cloern, C. Elfring, C. Hopkinson,
B. Lapointe, T. Malone, N. Marcus, K.J. McGlathery, A. Sharpley, and
D. Walker. 2000. Nutrient pollution of coastal rivers, bays, and
seas. Issues in Ecology 7:1-15.
Cloern, J.E. 2001. Our evolving conceptual model of the coastal
eutrophication problem. Marine Ecology Progress Series 210:223-253.
Elser, J.J., M.E.S. Bracken, E.E. Cleland, D.S. Gruner, W.S.
Harpole, H. Hillebrand, J.T. Ngai, E.W. Seabloom, J.B. Shurin, and
J.E. Smith. 2007. Global analysis of nitrogen and phosphorus
limitation of primary production in freshwater, marine, and
terrestrial ecosystems. Ecology Letters 10:1135-1142.
Smith, V.H. 2006. Responses of estuarine and coastal marine
phytoplankton to nitrogen and phosphorus enrichment. Limnology and
Oceanography 51(1, part 2): 377-384.
Vitousek, P.M., J.D. Aber, R.W. Howarth, G.E. Likens, P.A.
Matson, D.W. Schindler, W.H. Schlesinger, and D.G. Tilman. 1997.
Human alteration of the global nitrogen cycle: Sources and
consequences. Ecological Applications 7(3):737-750.
Bricker, S.B., J.G. Ferreira, and T. Simas. 2003. An integrated
methodology for assessment of estuarine trophic status. Ecological
Modelling 169(1):39-60.
Bricker, S.B., B. Longstaff, W. Dennison, A. Jones, K. Boicourt,
C. Wicks, and J. Woerner. 2008. Effects of nutrient enrichment in
the nation's estuaries: A decade of change. Harmful Algae 8(1):21-
32.
Boyer, J.N., C.R. Kelble, P.B. Ortner, and D.T. Rudnick. 2009.
Phytoplankton bloom status: Chlorophyll a biomass as an indicator of
water quality condition in the southern estuaries of Florida, USA.
Ecological Indicators 9(6, Supplement 1):S56-S67.
Hutchinson, G.E. 1961. The paradox of plankton. American
Naturalist 95:137-145.
Piehler, M.F., L.J. Twomey, N.S. Hall, and H.W. Paerl. 2004.
Impacts of inorganic nutrient enrichment on phytoplankton community
structure and function in Pamlico Sound, NC, USA. Estuarine Coastal
and Shelf Science 61(2):197-209.
Sanders, J.G., S.J. Cibik, C.F. D'Elia, and W.R. Boynton. 1987.
Nutrient enrichment studies in a coastal plain estuary: changes in
phytoplankton species composition. Canadian Journal of Fisheries &
Aquatic Sciences 44:83-90.
Parsons, T.R., P.J. Harrison, and R. Waters. 1978. An
experimental simulation of changes in diatom and flagellate blooms.
Journal of Experimental Marine Biology and Ecology 32:285-294.
Paerl, H.W. 1988. Nuisance phytoplankton blooms in coastal,
estuarine, and inland waters. Limnology and Oceanography 33(4):823-
847.
Harding, Jr., L.W. 1994. Long-term trends in the distribution of
phytoplankton in Chesapeake Bay: roles of light, nutrients, and
streamflow. Marine Ecology Progress Series 104:267-291.
Richardson, K. 1997. Harmful or Exceptional Phytoplankton Blooms
in the Marine Ecosystem. Advances in Marine Biology. 31:301-385.
Hagy, J.D., J.C. Kurtz, and R.M. Greene. 2008. An Approach for
Developing Numeric Nutrient Criteria for a Gulf Coast Estuary. U.S.
Environmental Protection Agency, Office of Research and Development,
National Health and Environmental Effects Research Laboratory,
Research Triangle Park, NC., EPA 600R-08/004, 44 pp.

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[[Page 74932]]

Nitrogen and phosphorus pollution increases algal growth that
negatively impacts many aspects of ecological communities. As algae
growth accelerates in response to nutrient pollution, there may be
negative changes in algal species composition and competition among
species, leading to harmful, adverse effects, such as the increased
growth or dominance of toxic or otherwise harmful algal species.\48\
These harmful algal blooms (HABs) can contain undesirable species of
diatoms, cyanobacteria, and dinoflagellates, which are known to
generate toxins that are a threat to both aquatic life and recreational
activities.\49\ Many nuisance taxa of algae are also less palatable to
aquatic organisms that consume phytoplankton, so prolonged HABs can
impact the food supply of the overall aquatic community. More than 100
HAB species have been identified in the United States.\50\
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\48\ Paerl, H.W. 1988. Nuisance phytoplankton blooms in coastal,
estuarine, and inland waters. Limnology and Oceanography 33(4):823-
847.
Anderson, D.M., P.M. Glibert, and J.M. Burkholder. 2002. Harmful
algal blooms and eutrophication: Nutrient sources, composition, and
consequences. Estuaries 25(4):704-726.
Anderson, D.M., J.M. Burkholder, W.P. Cochlan, P.M. Glibert,
C.J. Gobler, C.A. Heil, R.M. Kudela, M.L. Parsons, J.E.J. Rensel,
D.W. Townsend, V.L. Trainer, and G.A. Vargo. 2008. Harmful algal
blooms and eutrophication: Examining linkages from selected coastal
regions of the United States. Harmful Algae 8(1):39-53.
\49\ Anderson, D.M., P.M. Glibert, and J.M. Burkholder. 2002.
Harmful algal blooms and eutrophication: Nutrient sources,
composition, and consequences. Estuaries 25(4):704-726.
Paerl, H.W. 2002. Connecting atmospheric nitrogen deposition to
coastal eutrophication. Environmental Science & Technology
36(15):323A-326A.
Anderson, D.M., J.M. Burkholder, W.P. Cochlan, P.M. Glibert,
C.J. Gobler, C.A. Heil, R.M. Kudela, M.L. Parsons, J.E.J. Rensel,
D.W. Townsend, V.L. Trainer, and G.A. Vargo. 2008. Harmful algal
blooms and eutrophication: Examining linkages from selected coastal
regions of the United States. Harmful Algae 8(1):39-53.
\50\ Abbott, G.M., J.H. Landsberg, A.R. Reich, K.A. Steidinger,
S. Ketchen, and C. Blackmore. 2009. Resource Guide for Public Health
Response to Harmful Algal Blooms in Florida. FWRI Technical Report
TR-14. Florida Fish and Wildlife Conservation Commission, Fish and
Wildlife Research Institute, St. Petersburg, FL. http://myfwc.com/research/redtide/task-force/reports-presentations/resource-guide-for-public-health-response-to-harmful-algal-blooms-in-florida/Accessed June 2011.
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Marine and fresh waters of the United States are increasingly being
negatively impacted by HABs.\51\ HAB toxins have been linked to
illnesses and deaths of marine animals, including sea lions, turtles,
fish, seabirds, dolphins, and manatees.\52\ Diatoms in HABs, such as
Pseudo-nitzschia, produce domoic acid.\53\ Domoic acid has been shown
to accumulate in the tissue of mussels, crabs, and fish, causing their
predators to become ill or die.\54\ Domoic acid poisoning has been
reported as the cause of death of humpback whales in the Gulf of Maine
in 2003 and sea lions in California's Monterey Bay during May and June
of 1998.\55\ Other toxin-producing algal species that have been linked
to harmful, adverse aquatic life impacts include Pfisteria piscicida,
which produces several toxins that impact fish and humans \56\ and the
flagellate Heterosigma akashiwo which produces an ichthyotoxin that
kills fish.\57\
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\51\ Dortch, Q., P. Glibert, E. Jewett, and C. Lopez. 2008.
Introduction. Chapter 1 In: HAB RDDTT 2 National Workshop Report, A
plan for Reducing HABs and HAB Impacts. eds. Q. Dortch, D.M.
Anderson, D.L. Ayres, and P.M. Glibert, pp. 5-12. Woods Hole, MA.
\52\ WHOI. 2008. Marine Mammals. Woods Hole Oceanographic
Institution. http://www.whoi.edu/redtide/page.do?pid=14215. Accessed
June 2011.
WHOI. 2008. HAB Impacts on Wildlife. Woods Hole Oceanographic
Institution. http://www.whoi.edu/redtide/page.do?pid=9682. Accessed
June 2011.
NOAA. 2011. Overview of Harmful Algal Blooms. National Oceanic
and Atmospheric Administration, Center for Sponsored Coastal Ocean
Research.
http://www.cop.noaa.gov/stressors/extremeevents/hab/default.aspx. Accessed June 2011.
\53\ Thessen, A.E., and D.K. Stoecker. 2008. Distribution,
abundance and domoic acid analysis of the toxic diatom genus Pseudo-
nitzschia from the Chesapeake Bay. Estuaries and Coasts 31:664-672.
\54\ Bushaw-Newton, K.L., and K.G. Sellner. 1999. Harmful Algal
Blooms. In: NOAA's State of the Coast Report. National Oceanic and
Atmospheric Administration, Silver Spring, MD. http://oceanservice.noaa.gov/Web sites/retiredsites/sotc--pdf/hab.pdf.
Accessed June 2011.
\55\ MBARI. 2000, January 5. Molecular Probes Link Sea Lion
Deaths to Toxic Algal Bloom. MBARI News and Information. Monterey
Bay Aquarium Research Institute. http://www.mbari.org/news/news_releases/2000/jan06_scholin.html. Accessed June 2011.
\56\ Waring G.T., E. Josephson, K. Maze-Foley, and P.E. Rosel,
eds. 2010. Humpback Whale (Megaptera novaeangliae): Gulf of Maine
Stock (December 2009). In: U.S. Atlantic and Gulf of Mexico Marine
Mammal Stock Assessments--2010, NOAA Technical Memorandum NMFS-NE-
219. National Oceanic and Atmospheric Administration, National
Marine Fisheries Service, Northeast Fisheries Science Center, Woods
Hole, MA. http://www.nefsc.noaa.gov/publications/tm/tm219/. Accessed
January 2012.
\57\ Rensel, J.E.J. 2007. Fish kills from the harmful alga
Heterosigma akashiwo in Puget Sound: Recent blooms and review.
Prepared for National Oceanic and Atmospheric Administration, Center
for Sponsored Coastal Ocean Research, by Rensel Associates Aquatic
Sciences, Arlington, Washington, in cooperation with American Gold
Seafoods, LLC. http://www.whoi.edu/fileserver.do?id=39383&pt=2&p=29109. Accessed January 2012.
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Secondly, excessive algal growth as a result of nitrogen and
phosphorus pollution reduces water clarity, resulting in reduced light
availability for macrophytes and seagrasses.\58\ Seagrasses cover
approximately 2.7 million acres throughout the State and are a central
ecological feature of Florida's dynamic, highly productive marine
ecosystems.\59\ A substantial body of scientific research has linked
nitrogen and phosphorus pollution, and

[[Page 74933]]

subsequent reduced light availability, to seagrass decline. Excessive
nutrient inputs increase phytoplankton biomass and thereby increase
water column light attenuation, which limits the light available for
seagrass photosynthesis. This results in reduced growth and increased
mortality of seagrasses. In addition, nitrogen and phosphorus pollution
can lead to excess growth of epiphytic algae on seagrasses that blocks
the light available to seagrasses and affects seagrass growth.\60\ This
reduction of seagrass communities, in turn, results in harmful, adverse
impacts such as destabilization of sediments, which causes the release
of more nutrients into the water column.\61\
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\58\ Vitousek, P.M., J.D. Aber, R.W. Howarth, G.E. Likens, P.A.
Matson, D.W. Schindler, W.H. Schlesinger, and D.G. Tilman. 1997.
Human alteration of the global nitrogen cycle: Sources and
consequences. Ecological Applications 7(3):737-750.
Bricker, S.B., J.G. Ferreira, and T. Simas. 2003. An integrated
methodology for assessment of estuarine trophic status. Ecological
Modelling 169(1):39-60.
Bricker, S.B., B. Longstaff, W. Dennison, A. Jones, K. Boicourt,
C. Wicks, and J. Woerner. 2008. Effects of nutrient enrichment in
the nation's estuaries: A decade of change. Harmful Algae 8(1):21-
32.
Boyer, J.N., C.R. Kelble, P.B. Ortner, and D.T. Rudnick. 2009.
Phytoplankton bloom status: Chlorophyll a biomass as an indicator of
water quality condition in the southern estuaries of Florida, USA.
Ecological Indicators 9(6, Supplement 1):S56-S67.
\59\ FFWCC. 2003. Conserving Florida's Seagrass Resources:
Developing a Coordinated Statewide Management Program. Florida Fish
and Wildlife Conservation Commission, Florida Marine Research
Institute, St. Petersburg, FL.
\60\ Duarte, C.M. 1991. Seagrass depth limits. Aquatic Botany
40(4):363-377.
\61\ Boyer, J.N., C.R. Kelble, P.B. Ortner, and D.T. Rudnick.
2009. Phytoplankton bloom status: Chlorophyll a biomass as an
indicator of water quality condition in the southern estuaries of
Florida, USA. Ecological Indicators 9(6, Supplement 1):S56-S67.
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The role that nitrogen and phosphorus pollution plays in the
decline of seagrass has been studied extensively in Florida.\62\ In a
report published by USGS in 2001, six of nine Florida estuaries located
along the Gulf Coast showed declines in seagrass coverage, the
predominant causes of which were nitrogen and phosphorus pollution,
dredging, propeller scarring, hydrologic alterations, increased
turbidity, and chronic light reduction.\63\ Florida Fish & Wildlife
Conservation Commission has noted several areas of significant seagrass
decline between 1950 and 2000, including 72 percent loss in St. Joseph
Sound, 43 percent loss in the northern section of Biscayne Bay near
Miami, 40 percent loss in Tampa Bay, 30 percent loss in the Indian
River Lagoon, and 29 percent loss in Charlotte Harbor. These losses
coincided with population growth in these watersheds, and resulted from
human activities such as fertilizer use in residential and agricultural
areas and construction projects which contribute high levels of
suspended sediments.\64\ Several studies have attributed declines in
seagrass to excess chlorophyll a and phytoplankton in the water column
which can increase light attenuation. One study conducted from 1989-
1991 found that excess chlorophyll a caused light attenuation of 16 to
28 percent across Charlotte Harbor and Tampa Bay. In the same study,
the authors noted an overall improvement in seagrass recolonization and
areal cover in Hillsborough Bay and other parts of Tampa Bay starting
in the late 1980s coinciding with decreased nutrient loading, which
resulted in decreased concentrations of chlorophyll a and increased
water clarity.\65\ A later study, which conducted sampling monthly
between June 1998 and July 1999, estimated that phytoplankton biomass
contributed approximately 29 percent of total water column light
attenuation in Lemon Bay, Florida. The authors predicted a continuation
in the potential decline of seagrasses with increased urbanization.\66\
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\62\ Dawes, C.J., R.C. Phillips, and G. Morrison. 2004. Seagrass
Communities of the Gulf Coast of Florida: Status and Ecology, Final
Report. Technical Publication 03-04. Florida Fish and
Wildlife Conservation Commission, Fish and Wildlife Research
Institute, and the Tampa Bay Estuary Program, St. Petersburg, FL.
Tomasko, D.A., C.A. Corbett, H.S. Greening, and G.E. Raulerson.
2005. Spatial and temporal variation in seagrass coverage in
Southwest Florida: assessing the relative effects of anthropogenic
nutrient load reductions and rainfall in four contiguous estuaries.
Marine Pollution Bulletin 50:797-805.
Orth, R.J., T.J.B. Carruthers, W.C. Dennison, C.M. Duarte, J.W.
Fourqurean, K.L. Heck Jr., A.R. Hughes, G.A. Kendrick, W.J.
Kenworthy, S. Olyarnik, F.T. Short, M. Waycott, and S.L. Williams.
2006. A global crisis for seagrass ecosystems. Bioscience 56:987-
996.
Burkholder, J.M., D.A. Tomasko, and B.W. Touchette. 2007.
Seagrasses and eutrophication. Journal of Experimental Marine
Biology and Ecology 350:46-72.
Collado-Vides, L., V.G. Caccia, J.N. Boyer, and J.W. Fourqurean.
2007. Tropical seagrass-associated macroalgae distributions and
trends relative to water quality. Estuarine, Coastal and Shelf
Science 73:680-694.
\63\ USGS. 2001. Seagrass Habitat In the Northern Gulf of
Mexico: Degradation, Conservation, and Restoration of a Valuable
Resource. 855-R-04-001. U.S. Geological Survey, Gulf of Mexico
Habitat Program Team. http://gulfsci.usgs.gov/gom_ims/pdf/pubs_gom.pdf. Accessed July 2011.
\64\ FFWCC. 2002. Florida's Seagrass Meadows: Benefitting
Everyone. Florida Fish and Wildlife Conservation Commission, St.
Petersburg, FL. http://www.sarasotabay.org/documents/seagrassbrochure.pdf. Accessed July 2011.
\65\ McPherson, B.F., and R.L. Miller. 1994. Causes of Light
Attenuation in Tampa Bay and Charlotte Harbor, Southwestern Florida.
Water Resources Bulletin 30(1):43-53.
\66\ Tomasko, D.A., D.L. Bristol, and J.A. Ott. 2001. Assessment
of present and future nitrogen loads, water quality, and seagrass
(Thalassia testudinum) depth distribution in Lemon Bay, Florida.
Estuaries 24(6A):926-938.
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Lastly, excessive algal growth also leads to low dissolved oxygen
(DO) potentially creating hypoxic and anoxic conditions that cannot
support aquatic life and thereby can change the balance of natural
populations of aquatic fauna expected to occur.\67\ Hypoxia is
typically defined as DO < 2 mg/L, and anoxia as DO < 0.1 mg/L.\68\ The
cause and effect relationship between nitrogen and phosphorus pollution
and marine hypoxia is clear and well documented in the scientific
literature.\69\ Increased nitrogen and phosphorus inputs lead to
excessive algal growth and organic matter loading to bottom waters.
Bacterial decomposition of the organic matter consumes oxygen and
depletes the water column of DO.\70\ In estuaries and coastal waters,
low DO is one of the most widely reported consequences of nitrogen and
phosphorus pollution and one of the best predictors of a range of
biotic impairments.\71\ Low DO causes negative impacts to aquatic life
ranging from mortality to chronic impairment of growth and
reproduction.\72\ When nitrogen and phosphorus pollution creates
adverse conditions that result in large hypoxic zones, substantial
negative changes in fish, benthic, and plankton communities may
occur.\73\ This includes avoidance of these areas by fish, mobile
benthic invertebrates migrating from the hypoxic area, and fish kills
in some systems when fish and other mobile aquatic organisms have
nowhere to migrate away from the areas

[[Page 74934]]

with low DO.\74\ This can result in negative changes to the benthic
invertebrate community structure of estuaries and coastal areas, with
increases of organisms more tolerant of low DO.\75\ Even intermittent
hypoxia can cause shifts in the benthic assemblage to favor resistant
or tolerant organisms, which are less desirable food sources, creating
unbalanced benthic communities in the hypoxic zone because fish avoid
the area.\76\ When hypoxia extends into shallow waters, it affects
spawning and nursery areas for many important fish species by reducing
the habitat available that protects smaller fish and aquatic organisms,
especially juveniles, from predation.\77\ Hypoxia has been implicated
in a recent increase and late-summer dominance of hypoxia-tolerant
gelatinous zooplankton (jellyfish and ctenophores) in the Chesapeake
Bay and other eastern estuaries.\78\ Reduced fishery production in
hypoxic zones has been documented in the United States and
worldwide.\79\
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\67\ Vitousek, P.M., J.D. Aber, R.W. Howarth, G.E. Likens, P.A.
Matson, D.W. Schindler, W.H. Schlesinger, and D.G. Tilman. 1997.
Human alteration of the global nitrogen cycle: Sources and
consequences. Ecological Applications 7(3):737-750.
\68\ USEPA. 1999. The Ecological Condition of Estuaries in the
Gulf of Mexico. EPA 620-R-98-004. U.S. Environmental Protection
Agency, Office of Research and Development, National Health and
Environmental Effects Research Laboratory, Gulf Ecology Division,
Gulf Breeze, FL.
\69\ Conley, D., J. Carstensen, R. Vaquer-Sunyer, and C. Duarte.
2009. Ecosystem thresholds with hypoxia. Hydrobiologia 629(1):21-29.
Conley, D.J., H.W. Paerl, R.W. Howarth, D.F. Boesch, S.P.
Seitzinger, K.E. Havens, C. Lancelot, and G.E. Likens. 2009.
Controlling Eutrophication: Nitrogen and Phosphorus. Science
323(5917):1014-1015.
Diaz, R.J. 2001. Overview of hypoxia around the world. Journal
of Environmental Quality 30(2):275-281. Diaz, R.J., and R.
Rosenberg. 2008. Spreading dead zones and consequences for marine
ecosystems. Science 321(5891):926-929.
\70\ Clement, C., S.B. Bricker and D.E. Pirhalla. 2001.
Eutrophic Conditions in Estuarine Waters. In: NOAA's State of the
Coast Report. National Oceanic and Atmospheric Administration,
Silver Spring, MD. http://state-of-coast.noaa.gov/bulletins/html/eut_18/eut.html. Accessed December 2011.
\71\ Bricker, S.B., J.G. Ferreira, and T. Simas. 2003. An
integrated methodology for assessment of estuarine trophic status.
Ecological Modelling 169(1):39-60.
Bricker, S.B., C.G. Clement, D.E. Pirhalla, S.P. Orlando, and
D.R.G. Farrow. 1999. National Estuarine Eutrophication Assessment,
Effects of Nutrient Enrichment in the Nation's Estuaries. National
Oceanic and Atmospheric Administration, National Ocean Service,
Special Projects Office and the National Centers for Coastal Ocean
Science. Silver Spring, MD.
\72\ USEPA. 2001. Nutrient Criteria Technical Guidance Manual,
Estuarine and Coastal Marine Waters. EPA-822-B-01-003. U.S.
Environmental Protection Agency, Office of Water, Washington, DC.
\73\ Howell, P., and D. Simpson. 1994. Abundance of marine
resources in relation to dissolved oxygen in Long Island Sound.
Estuaries 17(2):394-402.
Kidwell, D.M., A.J. Lewitus, S. Brandt, E.B. Jewett, and D.M.
Mason. 2009. Ecological impacts of hypoxia on living resources.
Journal of Experimental Marine Biology and Ecology 381(Supplement
1):S1-S3.
\74\ Howell, P., and D. Simpson. 1994. Abundance of marine
resources in relation to dissolved oxygen in Long Island Sound.
Estuaries 17(2):394-402.
Kidwell, D.M., A.J. Lewitus, S. Brandt, E.B. Jewett, and D.M.
Mason. 2009. Ecological impacts of hypoxia on living resources.
Journal of Experimental Marine Biology and Ecology 381(Supplement
1):S1-S3.
\75\ Baker, S., and R. Mann. 1992. Effects of hypoxia and anoxia
on larval settlement, juvenile growth, and juvenile survival of the
oyster Crassostrea virginica. Biological Bulletin 182(2):265-269.
Baker, S., and R. Mann. 1994. Feeding ability during settlement
and metamorphosis in the oyster Crassostrea virginica (Gmelin, 1791)
and the effects of hypoxia on post-settlement ingestion rates.
Journal of Experimental Marine Biology and Ecology 181(2):239-253.
Baker, S.M., and R. Mann. 1994. Description of metamorphic
phases in the oyster Crassostrea virginica and effects of hypoxia on
metamorphosis. Marine Ecology Progress Series 104:91-99.
Baustian, M., and N. Rabalais. 2009. Seasonal composition of
benthic macroinfauna exposed to hypoxia in the northern Gulf of
Mexico. Estuaries and Coasts 32(5):975-983.
Breitburg, D. 2002. Effects of hypoxia, and the balance between
hypoxia and enrichment, on coastal fishes and fisheries. Estuaries
25(4):767-781.
\76\ Kidwell, D.M., A.J. Lewitus, S. Brandt, E.B. Jewett, and
D.M. Mason. 2009. Ecological impacts of hypoxia on living resources.
Journal of Experimental Marine Biology and Ecology 381(Supplement
1):S1-S3.
\77\ Breitburg, D. 2002. Effects of hypoxia, and the balance
between hypoxia and enrichment, on coastal fishes and fisheries.
Estuaries 25(4):767-781.
\78\ Grove, M., and D.L. Breitburg. 2005. Growth and
reproduction of gelatinous zooplankton exposed to low dissolved
oxygen. Marine Ecology Progress Series 301:185-198.
\79\ Diaz, R.J., and R. Rosenberg. 2008. Spreading dead zones
and consequences for marine ecosystems. Science 321(5891):926-929.
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Hypoxia and anoxia in bottom waters result in anoxia in the surface
sediments, which has geochemical consequences including acidification
and release of toxic hydrogen sulfide, soluble reactive phosphorus, and
ammonia.\80\ The sediment of hypoxic zones then becomes a potential
source of nutrients that can increase the degree of eutrophication.
Systems that have had persistent and chronic hypoxia often fail to
recover quickly even after pollution loadings have been reduced.\81\
Reduced oxygen also affects a variety of other biogeochemical processes
that can negatively impact water quality, such as the chemical form of
metals in the water column.\82\
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\80\ Diaz, R.J., and R. Rosenberg. 2008. Spreading dead zones
and consequences for marine ecosystems. Science 321(5891):926-929.
Kemp, W.M., W.R. Boynton, J.E. Adolf, D.F. Boesch, W.C.
Boicourt, G. Brush, J.C. Cornwell, T.R. Fisher, P.M. Glibert, J.D.
Hagy, L.W. Harding, E.D. Houde, D.G. Kimmel, W.D. Miller, R.I.E.
Newell, M.R. Roman, E.M. Smith, and J.C. Stevenson. 2005.
Eutrophication of Chesapeake Bay: Historical trends and ecological
interactions. Marine Ecology Progress Series 303:1-29.
McCarthy, M., K. McNeal, J. Morse, and W. Gardner. 2008. Bottom-
water hypoxia effects on sediment-water interface nitrogen
transformations in a seasonally hypoxic, shallow bay (Corpus Christi
Bay, TX, USA). Estuaries and Coasts 31(3):521-531.
Cai, W., X. Hu, W. Huang, M.C. Murrell, J.C. Lehrter, SE.
Lohrenz, W. Chou, W. Zhai, J.T. Hollibaugh, Y. Wang, P. Zhao, X.
Guo, K. Gundersen, M. Dai, and G. Gong.. 2011. Acidification of
subsurface coastal waters enhanced by eutrophication. Nature
Geoscience 4:766-770.
\81\ Conley, D.J., J. Carstensen, G. [AElig]rtebjerg, P.B.
Christensen, T. Dalsgaard, J.L.S. Hansen, and A.B. Josefson. 2007.
Long-term changes and impacts of hypoxia in Danish coastal water.
Ecological Applications 17(sp5):S165-S184.
Diaz, R.J., and R. Rosenberg. 2008. Spreading dead zones and
consequences for marine ecosystems. Science 321(5891):926-929.
\82\ Snoeyink, V.L., and D. Jenkins. 1980. Oxidation-Reduction
Reactions. Chapter 7 In: Water Chemistry, pp. 316-430. John Wiley
and Sons, New York.
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The harmful, adverse impacts of nitrogen and phosphorus pollution
on aquatic life have been manifested throughout Florida. The State has
been negatively impacted by algal blooms for many years. Red algae,
Laurencia intricata and Spyridia filamentosa; brown algae, Dictyota sp.
and Sargassum filipendula; and green algae, Enteromorpha sp., Codium
isthmocladum, and Halimeda sp. grow in the Florida Bay area.\83\ At
times their increased growth has threatened the commercially important
fish, lobster, and shrimp nurseries in the area.\84\ Southern Palm
Beach and northern Broward counties have been negatively impacted by
algal mats made up of Caulerpa species since the 1990s. Caulerpa
species can become overgrown or displace coral, other macroalgae, or
sponges. Off Palm Beach County, dive operators and fishermen have
reported large amounts of Caulerpa brachypus driving fish and lobster
away from reefs. Researchers in Florida (e.g., Florida Sea Grant,
University of Florida IFAS Extension, University of Central Florida,
Tampa Bay Estuary Program) and nationally (e.g., National Sea Grant,
NOAA) have noted the spread of a related green alga (Caulerpa
taxifolia) along the California coast, which is illustrative of the
potential for future further spread of C. brachypus in Florida coastal
waters. California is spending millions to eradicate the C.
taxifolia.\85\ Gambierdiscus toxicus (a ciguatoxin producer) is found
from Palm Beach to the Dry Tortugas and Florida Bay and is suspected to
have caused fish kills and disease events.\86\ Blooms of Lyngbya
majuscula were reported in Charlotte Harbor, Cedar Key, Sebastian
Inlet, Sarasota Bay, Tampa Bay, Terra Ceia Bay, Palma Sola, Manatee
River, and northwest Bradenton in 1999, 2000, and 2002. Lyngbya
majuscula can form sizeable, floating mats that emit foul odors.\87\ In
1991, widespread and persistent blooms of cyanobacteria in Florida Bay
coincided with massive sponge die-offs, which negatively impacted the
behavior and abundance of populations of juvenile Caribbean spiny
lobsters.\88\ Two Pseudo-nitzschia species found in Florida are P.
calliantha, which was observed at bloom levels in the northern Indian
River Lagoon, and P.

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pseudodelicatissima.\89\ Pseudo-nitzschia spp. has been observed in
Tampa Bay since the 1960s. Pseudo-nitzschia spp. cause amnesic
shellfish poisoning in humans and mortality of marine mammals and
seabirds.\90\
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\83\ Anderson, D.M., ed. 1995. ECOHAB: The Ecology and
Oceanography of Harmful Algal Blooms: A National Research Agenda.
Woods Hole Oceanographic Institution, Woods Hole, MA.
\84\ Anderson, D.M., ed. 1995. ECOHAB: The Ecology and
Oceanography of Harmful Algal Blooms: A National Research Agenda.
Woods Hole Oceanographic Institution, Woods Hole, MA.
\85\ Jacoby, C., B. Lapointe, and L. Creswell. No date. Are
native and nonindigenous seaweeds overgrowing Florida's east coast
reefs? SGEF-156. Florida Sea Grant College Program. http://nsgl.gso.uri.edu/flsgp/flsgpg01015.pdf. Accessed January 2012.
Jacoby, C., and L. Walters. 2009. Can We Stop ``Killer Algae''
from Invading Florida? (March 2009 rev.) SGEF-155. Florida Sea Grant
College Program. http://edis.ifas.ufl.edu/pdffiles/sg/sg07200.pdf.
Accessed April 2012.
\86\ FFWCC. No date. Gambierdiscus toxicus. Florida Fish and
Wildlife Conservation Commission. http://myfwc.com/media/202186/g_toxicus_1054.pdf. Accessed January 2012.
\87\ FFWCC. No date. Blue-Green Algal Blooms in Coastal Florida;
1999, 2000, and 2002. Florida Fish and Wildlife Conservation
Commission. http://myfwc.com/research/redtide/archive/historical-events/blue-green-algal-blooms-coastal-fl/. Accessed January 2012.
\88\ Butler, M.J., J.H. Hunt, W.F. Herrnking, M.J. Childress, R.
Bertelsen, W. Sharp, T. Matthews, J.M. Field, and H.G. Marshall.
1995. Cascading disturbances in Florida Bay, USA: cyanobacteria
blooms, sponge mortality, and implications for juvenile spiny
lobsters Panulirus argus. Marine Ecology Progress Series 129:119-
125.
\89\ Phlips, E.J., S. Badylak, M. Christman, J. Wolny, J. Brame,
J. Garland, L. Hall, J. Hart, J. Lansberg, M. Lasi, J. Lockwood, R.
Paperno, D. Scheidt, A. Staples, K. Steidinger. 2011. Scales of
temporal and spatial variability in the distribution of harmful
algae species in the Indian River Lagoon, Florida, USA. Harmful
Algae 10:277-290.
Phlips, E.J., S. Badylak, S. Youn, and K. Kelley. 2004. The
occurrence of potentially toxic dinoflagellates and diatoms in a
subtropical lagoon, the Indian River Lagoon, Florida, USA. Harmful
Algae 3(1):39-49.
\90\ Badylak, S., E.J. Phlips, P. Baker, J. Fajans, and R.
Boler. 2007. Distributions of phytoplankton in Tampa Bay estuary,
U.S.A. 2002-2003. Bulletin of Marine Science 80(2):295-317.
Lopez, C.B., Q. Dortch, E.B. Jewett, and D. Garrison. 2008.
Scientific Assessment of Marine Harmful Algal Blooms. Interagency
Working Group on Harmful Algal Blooms, Hypoxia, and Human Health of
the Joint Subcommittee on Ocean Science and Technology, Washington,
DC. http://www.cop.noaa.gov/stressors/extremeevents/hab/habhrca/assess_12-08.pdf. Accessed April 2012.
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In addition to being negatively indirectly impacted by algal toxins
and decline of seagrass, aquatic life in Florida is directly impacted
by hypoxia. In June 2011, a fish kill in Marco Island, Florida was
attributed to low dissolved oxygen, resulting from a ``mixed'' bloom of
non-toxic algae and diatoms.\91\ In 2010, there were reports of algal
blooms and fish kills in the St. Johns River.\92\ Spring releases of
water from Lake Okeechobee into the St. Lucie Canal resulted in
floating mats of toxic cyanobacteria, Microcystis aeruginosa, prompting
Martin and St. Lucie county health departments to issue public health
warnings.\93\ A large Microcystis bloom was documented in the Lower St.
Johns River in 2005, covering a 100 mi (160 km) stretch from
Jacksonville to Crescent City.\94\ Toxic cyanobacteria Anabaena
circinalis and Cylindrospermopsis raciborskii have been implicated in
fish kills in the Lower St. Johns River basin.\95\ In addition, in June
2009, a large algal bloom stretching more than 14 mi (23 km) was
documented in Tampa Bay. This was linked to surface water runoff of
nutrients and pollutants (e.g., fertilizers, yard waste, animal feces)
that were washed into the bay from recent heavy rains.\96\
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\91\ Fish kill in island canals appears over. 2011, June 2.
Marconews.com -Marco Eagle. http://www.marconews.com/news/2011/jun/02/dead-fish-bad-smell-permeate-parts-island/?print=1. Accessed
January 2012.
\92\ Patterson, S. 2010, July 23. St John's River Looks Sick,
Nelson says. The Florida Times Union. http://jacksonville.com/news/metro/2010-07-23/story/st-johns-looks-sick-nelson-says. Accessed
September 2010.
Patterson, S. 2010, July 21. Foam on St. John's River Churns Up
Environmental Interest. The Florida Times Union. http://jacksonville.com/news/metro/2010-07-21/story/foam-st-johns-churns-environmental-questions. Accessed October 2010.
\93\ Killer, E. 2010, June 10. Blue-green Algae Found Floating
Near Palm City as Lake Okeechobee Releases Continue. TCPalm. http://www.tcpalm.com/news/2010/jun/10/blue-green-algae-found-floating-near-palm-city-o/. Accessed October 2010.
\94\ Aubel, M., P. D'Aiuto, A. Chapman, D. Casamatta, A. Reich,
S. Ketchen, and C. Williams. 2006. Blue-Green Algae in St. Johns
River, FL. Lakeline Summer 2006:40-45.
\95\ Abbott, G. M., J. H. Landsberg, A. R. Reich, K. A.
Steidinger, S. Ketchen, and C. Blackmore. 2009. Resource Guide for
Public Health Response to Harmful Algal Blooms in Florida. FWRI
Technical Report TR-14. Florida Fish and Wildlife Conservation
Commission, Fish and Wildlife Research Institute, St. Petersburg,
FL. http://myfwc.com/research/redtide/task-force/reports-presentations/resource-guide-for-public-health-response-to-harmful-algal-blooms-in-florida/. Accessed June 2011.
http://www.lsjr.org/pdf/ResourceGuide_FL_algal_blooms_2009.pdf. Accessed June 2011.
\96\ Pittman, C. 2009, June 26. Algae bloom one of largest in
Tampa Bay history. St. Petersburg Times. http://www.tampabay.com/news/environment/water/article1013322.ece. Accessed July 2010.
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Numerous algal blooms, some capable of producing toxins, foul
odors, and fish kills, occurred in Florida coastal areas, estuaries,
and canals in 2011. Green algae, known as June Grass, were found
washing onto local beaches on Okaloosa Island. The algae adhere to
swimmers, cover beaches and hinder fishing.\97\
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\97\ Tammen, K. 2011, April 20. It's not even June and the June
Grass is Back. Northwest Florida Daily News. http://www.nwfdailynews.com/news/grass-39438-island-okaloosa.html. Accessed
April 2011.
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In the Caloosahatchee River and estuary, high algae and salinity
levels caused the Olga water treatment plant in Lee County to close in
May 2011. Customers complained about unusual tastes and odors in their
drinking water. The blue-green algae bloom significantly affected areas
from the W.P. Franklin Lock and Dam, upstream through Alva and LaBelle,
Florida. The bloom caused fish, bird and shellfish mortalities, and
triggered the Lee County Health Department to issue warnings and
advisories on water and fish consumption as well as swimming. Toxic
blue-green algae species were identified in the bloom, including
Anabaena, Oscillatoria and Aphanizomenon sp.\98\
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\98\ Lee Closes a Water Plant; Blame Algae and Saltwater
intrusion in Caloosahatchee. 2011, May 19. CBS Wink News Now. http://www.winknews.com/Local-Florida/2011-05-19/Lee-Closes-a-Water-Plant-Blame-Algae-and-Salt-water-intrusion-in-Caloosahatchee. Accessed
December 2011.
Lollar, K. 2011, June 6. Bacterial bloom stains waterway up to
LaBelle. News-Press. http://www.marconews.com/news/2011/jun/02/dead-fish-bad-smell-permeate-parts-island/. Accessed June 2011.
Crisis in the Caloosahatchee: Algal blooms in local waters.
2011, June 8. Sanibel-Captiva Islander. http://sanibel-captiva-
islander.com/page/content.detail/id/511872/Crisis-in-the-
Caloosahatchee--Algal-blooms-in-local-waters.html?nav=5051. Accessed
June 2011.
Warning added for Lee County waters. 2011, June 16. CBS Wink
News Now.
http://www.winknews.com/Local-Florida/2011-06-16/Warning-added-for-Lee-County-waters. Accessed June 2011.
Cornwell, B. 2011, June 22. Algae Bloom doesn't deter everyone.
Fort Meyers Florida Weekly. http://fortmyers.floridaweekly.com/news/2011-06-22/Top_News/Algae_bloom_doesnt_deter_everyone.html.
Accessed June 2011.
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The Indian River Lagoon also experienced large and prolonged algae
blooms. High levels of green algae Resultor sp. were found from
Titusville to Melbourne and covering the entire Banana River. The algae
were thought to be responsible for killing hundreds of fish and
inhibiting seagrass growth.\99\ A large rust-colored bloom of
Pyrodinium bahamense formed in Old Tampa Bay in August 2011; the bloom
stretched from Safety Harbor to the Howard Frankland Bridge and was
thought to be caused by a combination of heat, rain, and fertilizer
runoff.\100\
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\99\ Florida Today. 2011, July 18. Green algae killing fish,
seagrass in northern Indian River Lagoon. 10 News WTSP--Tampa Bay.
http://www.wtsp.com/rss/article/201465/19/Green-algae-killing-fish-seagrass-in-northern-Indian-River-Lagoon. Accessed December 2011.
\100\ Reyes, R. 2011, August 31. Algae bloom continues to grow
in Old Tampa Bay. Tampa Bay Online. http://www2.tbo.com/news/breaking-news/2011/aug/31/1/algae-bloom-continues-to-grow-in-old-tampa-bay-ar-254281/. Accessed December 2011.
Harwell, D. 2011, August 27. Tampa Bay algae bloom threatens the
estuary's fish. St. Petersburg Times. http://www.tampabay.com/news/environment/water/tampa-bay-algae-bloom-threatens-the-estuarys-fish/1188284. Accessed August 2011.
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c. Adverse Impacts of Nitrogen and Phosphorus Pollution on Human Health
As noted previously in section II.A.1.b, nitrogen and phosphorus
pollution have been explicitly linked to changes in natural algal
species composition including increased growth or dominance of toxic or
otherwise harmful algal species.\101\ Toxins produced by HABs have been
linked, through recreational exposure, to adverse human health impacts
through ingestion of contaminated seafood,

[[Page 74936]]

dermal reactions, and respiratory problems.\102\ Ingestion of seafood
that is contaminated with toxins can cause gastrointestinal,
neurological, cardiovascular, and hepatological illnesses. In some
severe cases, ingestion of even a small amount of contaminated seafood
can result in coma or death.\103\
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\101\ Paerl, H.W. 1988. Nuisance phytoplankton blooms in
coastal, estuarine, and inland waters. Limnology and Oceanography
33(4):823-847.
Anderson, D.M., P.M. Glibert, and J.M. Burkholder. 2002. Harmful
algal blooms and eutrophication: Nutrient sources, composition, and
consequences. Estuaries 25(4):704-726.
Anderson, D.M., J.M. Burkholder, W.P. Cochlan, P.M. Glibert,
C.J. Gobler, C.A. Heil, R.M. Kudela, M.L. Parsons, J.E.J. Rensel,
D.W. Townsend, V.L. Trainer, and G.A. Vargo. 2008. Harmful algal
blooms and eutrophication: Examining linkages from selected coastal
regions of the United States. Harmful Algae 8(1):39-53.
\102\ WHOI. 2006. Harmful Algae and Red Tides Primer. Woods Hole
Oceanographic Institution, Woods Hole, MA.
Anderson, D.M. 2004. The Growing Problem of Harmful Algae: Tiny
plants pose a potent threat to those who live in and eat from the
sea. Woods Hole Oceanographic Institution. Oceanus Magazine 43(1):1-
5.
Graham, J. 2007. Harmful Algal Blooms. Fact Sheet 2006-3147.
U.S. Geological Survey, Lawrence, KS CDC. 2004. About Harmful Algal
Blooms. Centers for Disease Control and Prevention, Atlanta, GA
Bronstein, A.C., D.A. Spyker, L.R. Cantilena, Jr., J.L. Green, B.H.
Rumack, S.L. Giffin. 2009. 2008 Annual Report of the American
Association of Poison Control Centers' National Poison Data System
(NPDS): 26th Annual Report. Clinical Toxicology 48:979-1178.
Landsberg, J., F.Van Dolah, and G. Doucette. 2005. Marine and
estuarine harmful algal blooms: Impacts on human and animal health.
Chapter 8 In: Oceans and Health: Pathogens in the Marine
Environment. eds. S. Belkin and R.R. Colwell, pp.165-215. Springer,
New York.
NOAA. 2009. Marine Biotoxins. National Oceanic and Atmospheric
Administration, Northwest Fisheries Science Center. http://www.nwfsc.noaa.gov/hab/habs_toxins/marine_biotoxins/index.html.
Accessed December 2011.
Anderson, D., P. Glibert, and J. Burkholder. 2002. Harmful Algal
Blooms and Eutrophication: Nutrient Sources, Composition, and
Consequences. Estuaries 25(4b):704-726.
\103\ Bushaw-Newton, K.L., and K.G. Sellner. 1999. Harmful Algal
Blooms. In: NOAA's State of the Coast Report. National Oceanic and
Atmospheric Administration, Silver Spring, MD. http://oceanservice.noaa.gov/websites/retiredsites/sotc_pdf/hab.pdf.
Accessed June 2011.
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Nitrogen and phosphorus pollution has been linked to human health
impacts in Florida, primarily through illnesses associated with HABs.
Although marine HABs occur naturally, increased nutrient loadings and
pollution have been linked to increased occurrence of some types of
HABs.\104\ Significant HAB-caused toxins that have been found in
Florida's marine waters include saxitoxins, brevetoxins, ciguatoxins,
cyanotoxins, domoic acid, and okadaic acid.\105\
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\104\ Lopez, C.B., Q. Dortch, E.B. Jewett, and D. Garrison.
2008. Scientific Assessment of Marine Harmful Algal Blooms.
Interagency Working Group on Harmful Algal Blooms, Hypoxia, and
Human Health of the Joint Subcommittee on Ocean Science and
Technology, Washington, DC.
\105\ Abbott, G.M., J.H. Landsberg, A.R. Reich, K.A. Steidinger,
S. Ketchen, and C. Blackmore. 2009. Resource Guide for Public Health
Response to Harmful Algal Blooms in Florida. FWRI Technical Report
TR-14. Florida Fish and Wildlife Conservation Commission, Fish and
Wildlife Research Institute, St. Petersburg, FL. http://myfwc.com/research/redtide/task- force/reports-presentations/resource-guide-
for-public-health-response-to-harmful-algal-blooms-in-florida/.
Accessed June 2011.
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Ciguatoxins lead to Ciguatera fish poisoning (CFP), one of the most
commonly reported food borne illnesses caused by a marine biotoxin in
the United States,\106\ with 176 cases reported to U.S. poison centers
in 2009 (22 percent of the total reported cases of food poisoning from
seafood toxins).\107\ Ciguatoxins are bioaccumulative, causing
gastrointestinal, neurological, or cardiovascular symptoms that vary in
intensity.\108\ In Florida, CFP poses a significant risk to public
health.\109\ One estimate indicates that approximately 1,300 cases of
CFP (reported and unreported cases) occur annually in Florida.\110\ The
Florida Department of Health (FDOH) reported 8 cases of CFP in 2005, 44
cases in 2006, 34 cases in 2007, and 51 cases in 2008.\111\
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\106\ Dickey, R.W., and S.M. Plakas. 2010. Ciguatera: A public
health perspective. Toxicon 56:123-136.
\107\ Bronstein, A.C., D.A. Spyker, L.R. Cantilena, Jr., J.L.
Green, B.H. Rumack, and S.L. Giffin. 2009. 2008 Annual Report of the
American Association of Poison Control Centers' National Poison Data
System (NPDS): 26th Annual Report. Clinical Toxicology 48:979-1178.
\108\ McKee D.B., L.E. Fleming, R. Tamer, R. Weisman, and D.
Blythe. 2001. Physician diagnosis and reporting of ciguatera fish
poisoning in an endemic area. In: Harmful Algal Blooms 2000:
Proceedings of the Ninth International Conference on Harmful Algal
Blooms, Hobart, Australia, 7-11 February 2000, eds. G.M.
Hallegraeff, S.I. Blackburn, C.J. Bolch, and R.J. Lewis, pp. 451-
453. Intergovernmental Oceanographic Commission of UNESCO, Paris,
France.
\109\ Abbott, G. M., J. H. Landsberg, A.R. Reich, K.A.
Steidinger, S. Ketchen, and C. Blackmore. 2009. Resource Guide for
Public Health Response to Harmful Algal Blooms in Florida. FWRI
Technical Report TR-14. Florida Fish and Wildlife Conservation
Commission, Fish and Wildlife Research Institute, St. Petersburg,
FL. http://myfwc.com/research/redtide/task-force/reports-presentations/resource-guide-for-public-health-response-to-harmful-algal-blooms-in-florida/. Accessed June 2011.
\110\ Abbott, G. M., J. H. Landsberg, A.R. Reich, K.A.
Steidinger, S. Ketchen, and C. Blackmore. 2009. Resource Guide for
Public Health Response to Harmful Algal Blooms in Florida. FWRI
Technical Report TR-14. Florida Fish and Wildlife Conservation
Commission, Fish and Wildlife Research Institute, St. Petersburg,
FL. http://myfwc.com/research/redtide/task- force/reports-
presentations/resource-guide-for-public-health-response-to-harmful-
algal-blooms-in-florida/. Accessed June 2011.
\111\ Abbott, G. M., J.H. Landsberg, A.R. Reich, K.A.
Steidinger, S. Ketchen, and C. Blackmore. 2009. Resource Guide for
Public Health Response to Harmful Algal Blooms in Florida. FWRI
Technical Report TR-14. Florida Fish and Wildlife Conservation
Commission, Fish and Wildlife Research Institute, St. Petersburg,
FL. http://myfwc.com/research/redtide/task-force/reports-presentations/resource-guide-for-public-health-response-to-harmful-algal-blooms-in-florida/. Accessed June 2011.
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Saxitoxins lead to paralytic shellfish poisoning (PSP), which
occurs when humans eat shellfish contaminated with saxitoxins. These
toxins affect the nervous system and in severe cases cause respiratory
paralysis.\112\ Between January 2002 and May 2004, 28 cases of
saxitoxin poisoning associated with puffer fish caught in Florida's
Indian River Lagoon (IRL) were reported. In 2002, the Florida Fish and
Wildlife Conservation Commission banned the commercial and recreational
harvest of puffer fish in several water bodies in Florida and made that
ban permanent in 2004.\113\ Domoic acid, also produced by HABs, can
also cause food poisoning, producing symptoms ranging from mild
gastrointestinal discomfort to permanent brain damage and, in rare
cases, death.\114\
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\112\ Landsberg, J., F. Van Dolah, and G. Doucette. 2005. Marine
and estuarine harmful algal blooms: Impacts on human and animal
health. Chapter 8 In: Oceans and Health: Pathogens in the Marine
Environment. eds. S. Belkin and R.R. Colwell, pp. 165-215. Springer,
New York.
\113\ Abbott, G.M., J.H. Landsberg, A.R. Reich, K.A. Steidinger,
S. Ketchen, and C. Blackmore. 2009. Resource Guide for Public Health
Response to Harmful Algal Blooms in Florida. FWRI Technical Report
TR-14. Florida Fish and Wildlife Conservation Commission, Fish and
Wildlife Research Institute, St. Petersburg, FL. http://myfwc.com/research/redtide/task-force/reports-presentations/resource-guide-for-public-health-response-to-harmful-algal-blooms-in-florida/.
Accessed June 2011.
Landsberg, J.H., S. Hall, J.N. Johannessen, K.D. White, S.M.
Conrad, J.P. Abbott, L.J. Flewelling, R.W. Richardson, R.W. Dickey,
E.L.E. Jester, S. M. Etheridge, J.R. Deeds, F.M. Van Dolah, T.A.
Leighfield, Y. Zou, C.G. Beaudry, R.A. Benner, P.L. Rogers, P.S.
Scott, K. Kawabata, J.L. Wolny, and K.A. Steidinger. 2006. Saxitoxin
Puffer Fish Poisoning in the United States, with the First Report of
Pyrodinium bahamense as the Putative Toxin Source. Environmental
Health Perspectives 114(10):1502-1507.
\114\ NOAA. 2009. Marine Biotoxins. National Oceanic and
Atmospheric Administration, Northwest Fisheries Science Center.
http://www.nwfsc.noaa.gov/hab/habs_toxins/marine_biotoxins/index.html. Accessed December 2011.
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In addition, elevated levels of nitrate, a byproduct of nitrogen
pollution in surface waters, can cause public health concerns if the
water is a drinking water source, where \115\ nitrate is converted to
harmful nitrite after ingestion.\116\ The primary human health concern
with nitrates and nitrites in drinking water is methemoglobinemia,
although adverse thyroid effects have been associated with elevated
nitrates as well.\117\

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Methemoglobinemia, or ``blue baby syndrome,'' as the name implies, most
often affects infants less than six months old (although adults can
also be affected) when the ingested nitrate is converted to nitrite in
the body that prevents hemoglobin in the blood from delivering oxygen
effectively throughout the body. Methemoglobinemia is an acute disease
and symptoms can develop rapidly in infants, usually over a period of
days. Symptoms include shortness of breath and blueness of the skin,
and even death in severe cases.\118\
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\115\ FDEP. 1998. Ground-water Quality and Agricultural Land Use
in the Polk County Very Intense Study Area (VISA). AMR 1998-2.
Florida Department of Environmental Protection, Division of Water
Facilities. http://www.dep.state.fl.us/water/monitoring/docs/facts/fs9802.pdf. Accessed September 2010.
\116\ Gulis. G., M. Czompolyova, and J.R. Cerhan. 2002. An
Ecologic Study of Nitrate in Municipal Drinking Water and Cancer
Incidence in Trnava District, Slovakia. Environmental Research
88:182-187.
\117\ Fan, A.M., and V.E. Steinberg. 1996. Health implications
of nitrate and nitrite in drinking water: An update on
methemoglobinemia occurrence and reproductive and development
toxicity. Regulatory Toxicology and Pharmacology 23(1 Pt 1):35-43.
\118\ Manassaram, D.M., L.C. Backer, and D.M. Moll. 2006. A
Review of Nitrates in Drinking Water: Maternal Exposure and Adverse
Reproductive and Developmental Outcomes. Environmental Health
Perspectives 114(3):320-327. FDEP. 2011. Drinking Water: Inorganic
Contaminants. Florida Department of Environmental Protection. http://www.dep.state.fl.us/water/drinkingwater/inorg_con.htm. Accessed
November 2011.
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EPA developed a Maximum Contaminant Level (MCL) of 10 mg/L for
nitrate in drinking water and an MCL of 1 mg/L for nitrite.\119\
Nitrates are found in groundwater and wells in Florida, ranging from
the detection limit of 0.02 mg/L to over 20 mg/L. Elevated nitrate
concentrations in groundwater are more common in rural agricultural
areas which are often served by private wells. When nitrate occurs at
concentrations greater than 1 mg/L, it is considered to be the result
of human activities such as application of agricultural fertilizers,
disposal of animal wastes, and use of septic tanks.\120\ Monitoring of
Florida Public Water Supplies from 2004-2011 indicates that exceedances
of the nitrate MCL reported by drinking water plants in Florida ranged
from 19-34 annually.\121\ A study in the late 1980s conducted by
Florida Department of Agriculture and Consumer Services (FDACS) and
FDEP, analyzed 3,949 shallow drinking water wells for nitrate.\122\
Nitrate was detected in 2,483 wells (63%), with 584 wells (15%) above
the MCL of 10 mg/L.
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\119\ USEPA. 2007. Nitrates and Nitrites: TEACH Chemical
Summary. U.S. Environmental Protection Agency. http://www.epa.gov/teach/chem_summ/Nitrates_summary.pdf. Accessed May 2012.
\120\ DeSimone, L.A., P.A. Hamilton, and R.J. Gilliom. 2009.
Quality of Water from Domestic Wells in Principal Aquifers of the
United States, 1991-2004: Overview of Major Findings. Circular
1332.U.S. Geological Survey, National Water Quality Assessment
Program, Reston, VA. http://water.usgs.gov/nawqa/studies/domestic_wells/WaterWellJournalArticle_DeSimoneetal2009.pdf. Accessed
November 2011.
Spechler, R.M. 2010. Hydrogeology and Groundwater Quality of
Highlands County, Florida. Scientific Investigations Report 2010-
5097. U.S. Geological Survey, Reston, VA
Dubrovsky, N.M., K.R. Burow, G.M. Clark, J.M. Gronberg, P.A.
Hamilton, K.J. Hitt, D.K. Mueller, M.D. Munn, B.T. Nolan, L.J.
Puckett, M.G. Rupert, T.M. Short, NE. Spahr, L.A. Sprague, and W.G.
Wilber. 2010. The Quality of our Nation's Waters--Nutrients in the
Nation's Streams and Groundwater, 1992-2004. Circular 1350. U.S.
Geological Survey, National Water Quality Assessment Program,
Reston, VA. http://water.usgs.gov/nawqa/nutrients/pubs/circ1350.
Accessed May 2012.
\121\ FDEP. 2012. Chemical Data for 2004, 2005, 2006, 2007,
2008, 2009, 2010, and 2011. Florida Department of Environmental
Protection. http://www.dep.state.fl.us/water/drinkingwater/chemdata.htm. Accessed May 2012.
\122\ Southern Regional Water Program. 2010. Drinking Water and
Human Health in Florida. http://srwqis.tamu.edu/florida/program-information/florida-target-themes/drinking-water-and-human-health.aspx. Accessed May 2012.
Obreza, T.A., and K.T. Morgan. 2008. Nutrition of Florida Citrus
Trees. 2nd ed. SL 253. University of Florida, IFAS Extension. http://edis.ifas.ufl.edu/pdffiles/SS/SS47800.pdf. Accessed May 2012.
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d. Adverse Impacts of Nitrogen and Phosphorus Pollution on the Economy
Excessive algal blooms result in a range of economic losses,
including lost revenue from impacts to commercial fisheries,
recreational fishing and boating trips, and tourism, as well as
increased drinking water costs and reduced waterfront property
values.\123\ More information concerning the costs and benefits of the
numeric nutrient criteria proposed in this rule can be found in Section
VI.
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\123\ Dodds, W.K., W.W. Bouska, J.L. Eitzmann, T.J. Pilger, K.L.
Pitts, A.J. Riley, J.T. Schloesser, and D.J. Thornbrugh. 2009.
Eutrophication of U.S. Freshwaters: Analysis of Potential Economic
Damages. Environmental Science and Technology 43(1):12-19.
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The economic value of Florida's marine recreational fisheries is
higher than any other state in the country. Recreational fishing
contributed over $5 billion to Florida's economy in 2006. In the 2008-
2009 fiscal year, over 1 million individuals bought a marine
recreational fishing license, generating over $29 million in
revenue.\124\ Similarly, Florida has one of the nation's top producing
commercial fisheries. In 2009, Florida's harvest of the top five
commercial species of fish and shellfish was worth more than $55
million combined. In total, commercial fishing contributed more than $1
billion to the economy of Florida. Outdoor recreation in Florida
(including wildlife-viewing, fishing, and water sports) generates $10.1
billion annually.\125\ In 2006, over 3 million Florida residents and
746,000 visitors participated in wildlife-viewing activities, for total
retail sales of an estimated $3.1 billion.\126\
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\124\ FFWCC. No Date. The Economic Impact of Saltwater Fishing
in Florida. Florida Fish and Wildlife Conservation Commission.
http://myfwc.com/conservation/value/saltwater-fishing. Accessed
December 2011.
\125\ FFWCC. No Date. Economic Impact of Outdoor Recreation.
Florida Fish and Wildlife Conservation Commission.
http://myfwc.com/conservation/value/outdoor-recreation. Accessed
July 2011.
\126\ USFWS. 2008. 2006 National Survey of Fishing, Hunting, and
Wildlife-Associated Recreation: Florida. FHW/06-FL. U.S. Fish and
Wildlife Service. http://www.census.gov/prod/2008pubs/fhw06-fl.pdf.
Accessed July 2011.
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At the county level, Monroe County's commercial tourism and fishing
industries rely on finfish and shellfish from Florida Bay. Measurable
economic losses associated with the changing environmental conditions
of the Bay have occurred, primarily from the substantial decline in
pink shrimp harvests due to loss of submerged aquatic vegetation
(habitat), which was linked to nitrogen and phosphorus pollution as a
contributing factor. From 1986 through the early 1990s, employment in
commercial fishing declined by about 10 percent, while income of
individuals in the industry declined by $16 million. These losses
coincided with massive seagrass die-offs in the Bay and blue-green
algae blooms.\127\
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\127\ Gorte, R.W. 1994. The Florida Bay economy and changing
environmental conditions. 94-435 ENR, CRS Report for Congress,
Congressional Research Service, The Library of Congress.
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HAB toxins can make seafood unsafe for human consumption, leading
to an overall reduction in the amount of fish purchased due to the real
or perceived threats of contamination.\128\ Potential economic impacts
from nitrogen and phosphorus pollution in Florida include monetary
losses due to depressed fisheries, tourism and property values, and
elevated costs to address nutrient impacts (e.g., beach cleanup costs,
HAB monitoring).
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\128\ Anderson, D.M.. 2008. Hearing on ``Harmful Algal Blooms:
The Challenges on the Nation's Coastlines''. Woods Hole
Oceanographic Institution. http://www.whoi.edu/page.do?pid=8916&tid=282&cid=46007. Accessed December 2011.
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Seagrass habitats are valuable components of Florida's estuarine
and coastal waters. FDEP has estimated that each acre of seagrass is
worth $20,255 per year, which would translate to a benefit of $44.6
billion statewide.\129\

[[Page 74938]]

The nearly 2.2 million acres of seagrass beds in Florida's nearshore
waters support fish and shellfish that are economically vital to
commercial and recreational businesses in Florida.\130\ Some estuary
experts have attempted to quantify the overall value of individual
estuaries in Florida. For example, the Indian River Lagoon National
Estuary Program estimated the total value of the Indian River Lagoon at
$3.7 billion (2009 dollars). In the study, recreational and non-use
values of the lagoon were estimated to increase by nearly $80 million
per year (2009 dollars) if there were a significant increase in the
amount and diversity of wildlife in the lagoon, as well as increased
water quality throughout the system from restoration and water quality
improvement projects.\131\
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\129\ USGS. 2001. Seagrass Habitat In the Northern Gulf of
Mexico: Degradation, Conservation, and Restoration of a Valuable
Resource. U.S. Geological Survey, Gulf of Mexico Habitat Program
Team,
855-R-04-001. http://gulfsci.usgs.gov/gom_ims/pdf/pubs_gom.pdf. Accessed July 2011.
Burkholder, J.M., D.A. Tomasko, and B.W. Touchette. 2007.
Seagrasses and eutrophication. Journal of Experimental Marine
Biology and Ecology 350:46-72.
Waycott, M., C.M. Duarte, T.J.B. Carruthers, R.J. Orth, W.C.
Dennison, S. Olyarnik, A. Calladine, J.W. Fourqurean, K.L. Heck,
Jr., A.R. Hughes, G.A. Kendrick, W.J. Kenworthy, F.T. Short, and
S.L. Williams. 2009. Accelerating loss of seagrasses across the
globe threatens coastal ecosystems. Proceedings of the National
Academy of Sciences of the United States of America 106(30):12377-
12381.
Short, F.T., B. Polidoro, S.R. Livingstone, K.E. Carpenter, S.
Bandeira, J.S. Bujang, H.P. Calumpong, T.J.B. Carruthers, R.G.
Coles, W.C. Dennison, P.L.A. Erftemeijer, M.D. Fortes, A.S. Freeman,
T.G. Jagtap, A.H.M. Kamal, G.A. Kendrick, W.J. Kenworthy, Y.A. La
Nafie, I.M. Nasution, R.J. Orth, A. Prathep, J.C. Sanciangco, B. van
Tussenbroek, S.G. Vergara, M. Waycott, and J.C. Zieman. 2011.
Extinction risk assessment of the world's seagrass species.
Biological Conservation144:1963-1971.
Watson R.A., R.G. Coles, and W.J. Lee Long. 1993. Simulation
estimates of annual yield and landed value for commercial penaeid
prawns from a tropical seagrass habitat, Northern Queensland,
Australia. Australian Journal of Marine and Freshwater Research
44:211-219.
Carlson, P., and L. Yarbro. 2008. Seagrass Mapping and
Monitoring: Big Bend and Beyond. Presented at Florida Water
Resources Monitoring Council Meeting, St. Petersburg, FL, September
24-25, 2008.
Costanza, R., R. d'Arge, R. de Groot, S. Farber, M. Grasso, B.
Hannon, K. Limburg, S. Naeem, R.V. Neill, J. Paruelo, R.G. Raskin,
P. Sutton, and M. van den Belt. 1997. The value of the world's
ecosystem services and natural capital. Nature 387:253-260.
\130\ FDEP. 2011. Celebrate Seagrass Awareness Month. Florida
Department of Environmental Protection. http://www.dep.state.fl.us/coastal/news/articles/2011/1103_Seagrass.htm. Accessed June 2011.
Scott, R. 2011. Seagrass Awareness Month. Proclamation by
Governor Rick Scott of the State of Florida. Florida Department of
Environmental Protection. http://www.dep.state.fl.us/coastal/habitats/seagrass/awareness/Proclamation_2011.pdf. Accessed June
2011.
\131\ USEPA. 2009. Determining an Estuary's Economic Value. EPA-
842F09001. U.S. Environmental Protection Agency, National Estuary
Program, Washington, DC. http://water.epa.gov/type/oceb/nep/upload/2009_05_28_estuaries_inaction_Efficient_IndianRiver.pdf.
Accessed July 2011.
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According to a study on the impacts of HABs on beachfront tourism-
dependent businesses in the Ft. Walton Beach and Destin areas of
Florida, HABs reduced restaurant and lodging revenues by $2.8 million
and $3.7 million per month, respectively, representing a 29 percent to
35 percent decline in average monthly revenues.\132\
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\132\ Larkin, S.L., and C.M. Adams. 2007. Harmful algal blooms
and coastal business: economic consequences in Florida. Society &
Natural Resources 20(9):849-859.
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A study by Mather Economics estimated the effects of water quality
on real estate value in the South Florida Water Management District.
The aggregate owner-occupied residential real estate value in the 16-
county South Florida Water Management District is approximately $976
billion. If water quality (measured by dissolved oxygen levels) can be
returned to 1970 levels as a result of restoring the Everglades (a
potential 23.4 percent improvement in water quality), the study found
that real estate values would increase by $16 billion.\133\
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\133\ McCormick, B., R. Clement, D. Fischer, M. Lindsay, R.
Watson. 2010. Measuring the Economic Benefits of America's
Everglades Restoration: An Economic Evaluation of Ecosystem Services
Affiliated with the World's Largest Ecosystem Restoration Project.
Prepared for the Everglades Foundation, Palmetto Bay, FL, by Mather
Economics, Roswell, GA.
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In addition to negatively impacting Florida businesses, nitrogen
and phosphorus pollution increases costs for beach cleanup, HAB
monitoring, and wastewater treatment. For example, approximately
$63,000 was spent annually from 1995-1997 to dispose of red seaweed and
fish killed by HAB events that littered 17.5 miles of beach in Sarasota
County.\134\
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\134\ Hoagland, P., D.M. Anderson, Y. Kaoru, and A.W. White.
2002. The economic effects of harmful algal blooms in the United
States: estimates, assessment issues, and information needs.
Estuaries 25:819-837.
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In addition, there are increased costs due to the need to treat
polluted sources of drinking water. As an example of increased costs
for drinking water treatment, in 1991, Des Moines (Iowa) Water Works
constructed a $4 million ion exchange facility to remove nitrate from
its drinking water supply. This facility was designed to be used an
average of 35-40 days per year to remove excess nitrate levels at a
cost of nearly $3,000 per day.\135\ In another example, Fremont, Ohio
(a city of approximately 20,000) has experienced high levels of nitrate
from its drinking water source, the Sandusky River, resulting in
numerous drinking water use advisories. An estimated $15 million is
needed to build a reservoir (and associated piping) that will allow for
selective withdrawal from the river to avoid elevated levels of nitrate
and provide storage.\136\ By regulating allowable levels of chlorophyll
a in Oklahoma drinking water reservoirs, the Oklahoma Water Resources
Board estimated that the long-term cost savings in averted drinking
water treatment for 86 systems would range between $106 million and
$615 million if such regulations were implemented.\137\ These
statistics are illustrative of what treatment to address nitrates and
nitrites can cost. Any impacts in Florida would be site-specific and
might or might not be comparable to these numbers.
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\135\ Jones, C.S., D. Hill, and G. Brand. 2007. Use a
multifaceted approach to manage high sourcewater nitrate. Opflow
June:20-22.
\136\ Taft, Jim, Association of State Drinking Water
Administrators (ASDWA). 2009. Personal Communication.
\137\ Moershel, Philip, Oklahoma Water Resources Board (OWRB)
and Mark Derischweiler, Oklahoma Department of Environmental Quality
(ODEQ). 2009. Personal Communication.
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B. Statutory and Regulatory Background

Section 303(c) of the CWA (33 U.S.C. 1313(c)) directs states to
adopt WQS for their navigable waters. CWA Section 303(c)(2)(A) and
EPA's implementing regulations at 40 CFR 131 require, among other
things, that state WQS include the designated use and criteria that
protect those uses. EPA regulations at 40 CFR 131.11(a)(1) provide that
states shall ``adopt those water quality criteria that protect the
designated use'' and that such criteria ``must be based on sound
scientific rationale and must contain sufficient parameters or
constituents to protect the designated use.'' In addition, 40 CFR
131.10(b) provides that ``[i]n designating uses of a water body and the
appropriate criteria for those uses, the state shall take into
consideration the water quality standards of downstream waters and
ensure that its water quality standards provide for the attainment and
maintenance of the water quality standards of downstream waters.''
States are also required to review their water quality standards at
least once every three years and, if appropriate, revise or adopt new
standards (CWA section 303(c)(1)). Any new or revised water quality
standards must be submitted to EPA for review and approval or
disapproval (CWA section 303(c)(2)(A) and (c)(3)). In addition, CWA
section 303(c)(4)(B) authorizes the Administrator to determine, even in
the absence of a state submission, that a new or revised standard is
needed to meet CWA requirements. The EPA approved the State of
Florida's rules (which include criteria for certain estuaries and
coastal marine waters) on November 30, 2012. The criteria proposed in
this rulemaking protect the uses designated by the State of Florida and
implement Florida's narrative nutrient provision at Subsection 62-
302.530(47)(b), F.A.C. for the purposes of the CWA. These criteria
include numeric values that apply to Florida's

[[Page 74939]]

estuaries and coastal waters not covered by the newly-approved State
WQS, south Florida inland flowing waters, and DPVs to ensure the
attainment and maintenance of the water quality standards of downstream
estuaries.\138\ As explained more fully in Section I.A, EPA does not
intend to finalize these DPVs if the district court modifies the
Consent Decree consistent with EPA's amended determination that numeric
DPVs are not necessary to meet CWA requirements in Florida.
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\138\ The criteria proposed in this rulemaking do not address or
implement Florida's narrative nutrient provision at Subsection 62-
302.530(47)(a), F.A.C. Subsection 62-302.530(47)(a), F.A.C. remains
in place as an applicable water quality standard for CWA purposes.
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C. Water Quality Criteria

Water quality criteria include three components. The first
component is ``magnitude,'' the concentration of a pollutant that can
be maintained over time in the ambient receiving water without
adversely affecting the designated use that the criteria is intended to
support. The second component is ``duration,'' or the time period over
which exposure is averaged (i.e., the averaging period) to limit the
time of exposure to elevated concentrations. This accounts for the
variability in the quality of the ambient water due to variations of
constituent inputs, flow, and other factors. The third component is
``frequency,'' or how often the magnitude/duration condition may be
exceeded and still protect the designated use. Combining the criterion-
magnitude with the duration and frequency prevents harmful effects from
infrequent exceedances of the criterion-magnitude by ensuring
compensating periods of time during which the concentration is below
the criterion-magnitude. When criterion-magnitudes are exceeded for
short periods of time or infrequently, aquatic life can typically
recover; that is, the designated uses of the water body are typically
protected. Designated uses are typically not protected when criterion-
magnitudes are exceeded for longer periods of time (i.e., for longer
than the specified duration) or more frequently (i.e., more often than
the allowed frequency).\139\ Use of this magnitude-duration-frequency
format allows for some exceedances of the criterion-magnitude
concentrations while still protecting applicable designated uses, which
is important for pollutants such as nitrogen and phosphorus because
their concentrations can vary naturally in the environment.
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\139\ USEPA. 1994. Water Quality Standards Handbook: Second
Edition, Chapter 3--Water Quality Criteria. EPA-823-B-94-005a. U.S.
Environmental Protection Agency, Office of Water, Washington, DC.
USEPA 1991. Technical Support Document for Water Quality-based
Toxics Control. Appendix D--Duration and Frequency. EPA/505/2-90-
001. U.S. Environmental Protection Agency, Office of Water,
Washington, DC.
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Under CWA section 304(a), EPA periodically publishes criteria
recommendations for use by states in setting water quality criteria for
particular parameters to protect recreational and aquatic life uses of
waters. Where EPA has published recommended criteria, states have the
option of adopting water quality criteria based on EPA's CWA section
304(a) criteria guidance, section 304(a) criteria guidance modified to
reflect site-specific conditions, or other scientifically defensible
methods (40 CFR 131.11(b)(1)).
For nitrogen and phosphorus pollution, EPA has published under CWA
section 304(a) a series of peer-reviewed, national technical approaches
and methods for the development of numeric nutrient criteria for lakes
and reservoirs,\140\ rivers and streams,\141\ and estuarine and coastal
marine waters.\142\ EPA based the methodologies used to develop numeric
nutrient criteria for Florida in this proposed regulation on these
published guidance documents, which identify three scientifically
defensible approaches for deriving nutrient criteria: (1) The reference
condition approach derives criteria from observations collected in
reference water bodies or during reference time periods; (2) the
mechanistic modeling approach represents contaminant loadings,
hydrodynamics, and impacts in aquatic systems using equations that
represent physical and ecological processes, calibrated using site-
specific data; and (3) the stressor-response approach estimates the
relationship between nutrient concentrations and response measures
related to a designated use of the water body. These three analytical
approaches have been independently peer-reviewed and are appropriate
for deriving scientifically defensible numeric nutrient criteria,
taking into consideration the method-specific data needs and available
data. In addition to these approaches, consideration of established
(e.g., published and peer-reviewed) nutrient response thresholds is
also an acceptable approach for deriving criteria.\143\
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\140\ USEPA. 2000a. Nutrient Criteria Technical Guidance Manual:
Lakes and Reservoirs. EPA-822-B-00-001. U.S. Environmental
Protection Agency, Office of Water, Washington, DC.
\141\ USEPA. 2000b. Nutrient Criteria Technical Guidance Manual:
Rivers and Streams. EPA-822-B-00-002. U.S. Environmental Protection
Agency, Office of Water, Washington, DC.
\142\ USEPA. 2001. Nutrient Criteria Technical Manual: Estuarine
and Coastal Marine Waters. EPA-822-B-01-003. U.S. Environmental
Protection Agency, Office of Water, Washington, DC.
\143\ USEPA. 2000a. Nutrient Criteria Technical Guidance Manual:
Lakes and Reservoirs. EPA-822-B-00-001. U.S. Environmental
Protection Agency, Office of Water, Washington, DC.
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The criteria proposed in this rulemaking implement Florida's
narrative nutrient provision at Subsection 62-302.530(47)(b), F.A.C.,
for the purposes of the CWA as numeric values that apply to, and
protect, Class I, II, and III estuaries and coastal waters in Florida
and south Florida inland flowing waters. In Florida, water quality
criteria established for Class I, II, and III surface waters must
protect ``fish consumption, recreation and the propagation and
maintenance of a healthy, well-balanced population of fish and
wildlife.'' \144\ Florida's existing narrative nutrient provision
serves to protect Class I, II, and III waters from nitrogen and
phosphorus pollution by requiring that ``[i]n no case shall nutrient
concentration of a body of water be altered so as to cause an imbalance
in natural populations of aquatic flora or fauna.''
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\144\ Pursuant to Subsection 62-302.400(4), F.A.C.
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After an extensive review of the latest scientific knowledge
relating to the impacts of nutrient pollution on aquatic systems, EPA
is proposing the use of three biological endpoints--maintenance of
seagrasses, maintenance of balanced algal populations, and maintenance
of aquatic life (fauna)--as the most sensitive to effectively derive
numeric nutrient criteria that will protect Class I, II, and III
designated uses from the harmful, adverse effects of nutrient
pollution. The endpoint measures that EPA is proposing to use to
determine the nutrient concentrations to protect these biological
endpoints are light levels to maintain historic depth of seagrass
colonization, chlorophyll a concentrations associated with balanced
phytoplankton biomass, and sufficient DO to maintain aquatic life. Fish
consumption relies on the presence of fish and aquatic life as well as
the habitat that supports them, which in turn relies on seagrasses and
limited occurrence of nuisance algal blooms. The protection of
recreation (both fishing and swimming related uses) relies on the
presence of fish and aquatic life as well as limited occurrence of
nuisance algal blooms. Lastly, the protection of propagation and
maintenance of a healthy, well-balanced population of fish and wildlife
relies on the presence of fish and

[[Page 74940]]

aquatic life as well as the habitat that supports them.
EPA's January 14, 2009 determination addressed Florida's narrative
nutrient provision at Subsection 62-302.530(47)(b), F.A.C. As discussed
earlier, EPA has proposed and promulgated criteria, in this and other
proposals, to implement that provision, which provides that ``[i]n no
case shall nutrient concentrations of a body of water be altered so as
to cause an imbalance in natural populations of aquatic flora or fauna.
The criteria proposed in this rulemaking do not address or implement
Florida's narrative nutrient provision at Subsection 62-302.530(47)(a),
F.A.C. which provides that ``[t]he discharge of nutrients shall
continue to be limited as needed to prevent violations of other
standards contained in this chapter. Human-induced nutrient enrichment
(total nitrogen or total phosphorus) shall be considered degradation in
relation to the provisions of Sections 62-302.300, 62-302.700, and 62-
4.242, F.A.C.'' Subsection 62-302.530(47)(a), F.A.C. remains in place
as an applicable WQS for CWA purposes and could result in more
stringent nitrogen and phosphorus limits than those proposed in this
rule, where necessary to protect other applicable water quality
standards in Florida.

D. EPA Determination Regarding Florida and Consent Decree

On January 14, 2009, EPA determined under CWA section 303(c)(4)(B)
that new or revised water quality standards in the form of numeric
water quality criteria for nitrogen and phosphorus pollution are
necessary to meet the requirements of the CWA in the State of Florida.
EPA's determination is available at the following Web site: http://water.epa.gov/lawsregs/rulesregs/florida_consent.cfm.
Subsequently, EPA entered into a Consent Decree with Florida
Wildlife Federation, Sierra Club, Conservancy of Southwest Florida,
Environmental Confederation of Southwest Florida, and St. Johns
Riverkeeper, effective on December 30, 2009, which established a
schedule for EPA to propose and promulgate numeric nutrient criteria
for Florida's lakes, springs, flowing waters, estuaries, and coastal
waters, as well as downstream protection values (DPVs) to protect
downstream lakes and estuaries. The Consent Decree provided that if
Florida submitted and EPA approved numeric nutrient criteria for the
relevant water bodies before the dates outlined in the schedule, EPA
would no longer be obligated to propose or promulgate criteria for
those water bodies.

E. EPA's Rulemaking and Subsequent Litigation

On December 6, 2010, EPA published a rule finalizing numeric
nutrient criteria for Florida's lakes, springs, and flowing waters
outside of the South Florida Nutrient Watershed Region (40 CFR 131.43).
The 2010 ``inland waters rule'' was previously scheduled to take effect
on March 6, 2012, with the exception of one provision that allowed
entities to submit Site-Specific Alternative Criteria (SSAC) effective
February 4, 2011. The March 6, 2012 effective date was subsequently
extended on two occasions (77 FR 13497 and 77 FR 39949) such that the
current effective date of the rule is January 6, 2013. Concurrently
with this proposal, EPA is issuing a separate proposed rule to stay the
inland waters rule until November 15, 2013. For more information on the
proposed stay rule, see http://water.epa.gov/lawsregs/rulesregs/florida_inland.cfm.
Following the publication of the inland waters rule, 12 cases were
filed in the U.S. District Court for the Northern District of Florida
challenging the rule. The cases, consolidated before Judge Robert
Hinkle in the Tallahassee Division of the Northern District, were filed
by environmental groups, Florida's State Department of Agriculture, the
South Florida Water Management District, and various industry/
discharger groups. The challenges alleged that EPA's determination and
final inland waters rule were arbitrary, capricious, an abuse of
discretion, and not in accordance with the law for a variety of
reasons. Oral argument in the case was held on January 9, 2012 before
Judge Hinkle.
On February 18, 2012, the Court upheld EPA's January 2009
determination and the final numeric nutrient criteria for Florida's
lakes and springs, as well as the site-specific alternative criteria
(SSAC) provisions and the provisions for calculating DPVs using either
modeling or a default option for an impaired lake that is not attaining
its numeric nutrient criteria.\145\ With regard to EPA's numeric
nutrient criteria for flowing waters (i.e., streams) and the default
option to calculate DPVs for unimpaired lakes based on ambient stream
nutrient concentrations at the point of entry to the lake, the Court
found that EPA had not provided sufficient information in its final
rule explaining why or how the criteria or DPV protect against harmful
increases, as opposed to any increase, in nutrients. The Court observed
that EPA's scientific approach to deriving stream criteria (i.e., the
reference condition approach), including the criteria's duration and
frequency components, ``are matters of scientific judgment on which the
rule would survive arbitrary-or-capricious review.'' The Court also
found, however, that EPA had not explained in sufficient detail how the
stream criteria would prevent a ``harmful increase in a nutrient
level''. In addition, the Court found that EPA had not explained in
sufficient detail how exceedances of the default DPV for unimpaired
lakes would lead to ``harmful effects'' in the downstream lake. Thus,
the Court invalidated these two aspects of EPA's final rule and
remanded them to the Agency for further action. Concurrently with this
proposal, EPA is issuing a separate proposed rule for Florida's streams
and DPVs for unimpaired lakes (Water Quality Standards for the State of
Florida's Streams and Downstream Protection Values for Lakes: Remanded
Provisions). For more information on the proposed rule for the remanded
provisions, see http://water.epa.gov/lawsregs/rulesregs/florida_inland.cfm.
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\145\ Case 4:08-cv-00324-RH-WCS, February 18, 2012.
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On several occasions, the court granted EPA's request to modify the
deadlines in the December 2009 Consent Decree.\146\ Under the revised
Consent Decree, EPA is required to propose criteria for Florida's
estuaries, coastal waters, and south Florida inland flowing waters by
November 30, 2012 and to finalize such criteria by September 30, 2013.
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\146\ http://water.epa.gov/lawsregs/rulesregs/florida_consent.cfm.
---------------------------------------------------------------------------

In accordance with the January 14, 2009 determination, the December
30, 2009 Consent Decree, and the subsequent modifications to the
deadlines in the December 30, 2009 Consent Decree, EPA is proposing in
this notice numeric nutrient criteria for estuaries and coastal waters
in the State of Florida, and south Florida inland flowing waters. This
proposed rule satisfies EPA's requirement to propose criteria for these
three categories of Florida waters by November 30, 2012.

F. Florida Adoption of Numeric Nutrient Criteria and EPA Approval

On June 13, 2012, FDEP submitted new and revised WQS for review by
the EPA pursuant to section 303(c) of the CWA. These new and revised
WQS are set out primarily in Rule 62-302 of the F.A.C. [Surface Water
Quality Standards]. FDEP also submitted amendments to Rule 62-303,
F.A.C. [Identification of Impaired Surface Waters], which sets out
Florida's methodology for assessing whether

[[Page 74941]]

waters are attaining State WQS. On November 30, 2012, EPA approved the
provisions of these rules submitted for review that constitute new or
revised WQS (referred to in this preamble as the ``newly-approved State
WQS'').
Among the newly-approved State WQS are numeric criteria for
nutrients that apply to a set of estuaries and coastal marine waters in
Florida. Specifically, these newly-approved State WQS apply to
Clearwater Harbor/St. Joseph Sound, Tampa Bay, Sarasota Bay, Charlotte
Harbor/Estero Bay, Clam Bay, Tidal Cocohatchee River/Ten Thousand
Islands, Florida Bay, Florida Keys, and Biscayne Bay. Under the Consent
Decree, EPA is relieved of its obligation to propose numeric criteria
for these waters.

III. Proposed Numeric Criteria for Florida's Estuaries, Coastal Waters,
and South Florida Inland Flowing Waters

In this notice of proposed rulemaking, EPA is proposing numeric
nutrient criteria to protect against harmful increases in nutrients,
and therefore, protect the designated uses of the State of Florida's
Class I, II, and III waters, specifically Florida's estuaries and
coastal waters (excluding those contained in Florida's newly-approved
State WQS), and south Florida inland flowing waters. This proposed rule
also includes downstream protection values (DPVs) to ensure the
attainment and maintenance of WQS in downstream estuarine and south
Florida marine waters. The proposed criteria and related provisions in
this rule reflect a detailed consideration of the best available
scientific research, data, and analyses related to the specific
circumstances for deriving numeric nutrient criteria in the State of
Florida. EPA's actions are consistent with and support existing Florida
WQS regulations.
EPA proposes developing numeric nutrient criteria to restore and
maintain the balance of natural populations of aquatic flora and fauna
in Florida waters. The analytical process that EPA used to derive the
proposed criteria consisted of several steps that included (1)
classification of the water body systems, (2) subdividing water body
systems into smaller segments that have similar chemical, physical, and
biological features, (3) review and analysis of biological endpoints,
and (4) application of one or more analytical methodologies.
After accounting for the spatial coverage of Florida's newly-
approved State WQS, EPA grouped Florida's remaining estuarine and
coastal waters according to the natural geographic features of
estuarine basins and their associated watersheds (classification). This
resulted in 19 estuarine systems and three coastal systems. Next, EPA
divided each resulting estuary and coastal system into segments on the
basis of similar biological, chemical, and physical attributes
(segmentation). Segmentation resulted in 89 estuarine segments among
the 19 estuarine systems and 71 coastal segments among the three
coastal systems. In the Big Bend region (Ochlockonee Bay to Springs
Coast) EPA combined coastal waters with estuarine waters for analysis.
The classification serves as an organizing framework for analyses, and
the segmentation delineates areas in each estuary or coastal system
where the numeric nutrient criteria apply.
EPA is proposing to develop numeric nutrient criteria for Florida's
estuarine and coastal waters based on three biological endpoints that
are sensitive to changes in nitrogen and phosphorus concentrations.
These biological endpoints reflect the water quality conditions
necessary to ensure protection of balanced populations of aquatic flora
and fauna: (1) Maintenance of seagrasses (as measured by water clarity
sufficient to maintain historic depth of seagrass colonization), (2)
maintenance of balanced algal populations (as measured by chlorophyll a
concentrations associated with balanced phytoplankton biomass), and (3)
maintenance of aquatic life (as measured by levels of dissolved oxygen
sufficient to maintain aquatic life). For each water body, EPA derived
numeric nutrient criteria based on the most nutrient sensitive of the
three endpoints and the sufficiency of data available in each segment.
For each estuary and coastal system, one of three analytical
approaches was used to derive numeric nutrient criteria--reference
condition, stressor-response (statistical modeling), and mechanistic
modeling. In some cases, a secondary approach provided corroborating
evidence for the results of the primary analytical methodology. EPA
evaluated multiple lines of evidence to determine the analytical
approach that was best suited for derivation of numeric nutrient
criteria in each estuarine or coastal system. In general, and as
discussed in more detail in later Sections of this proposed rule, the
reference condition approach was applied when there were sufficient
data available to characterize conditions that were representative of
and protective of designated uses, the stressor-response approach was
applied when there were sufficient data available to statistically
quantify relationships between nutrient concentrations and the
biological endpoints, and lastly, the mechanistic modeling approach was
applied when there were sufficient data and information available to
quantify the relationships between nutrient loads and the biological
endpoints.
For calculating DPVs for estuaries and south Florida marine waters,
EPA is proposing four approaches for setting nitrogen and phosphorus
protective levels in a hierarchy that reflects the data and scientific
information available, including (1) water quality simulation modeling,
(2) reference condition approach, (3) dilution models, and (4) the
numeric nutrient criteria in the estuarine segment to which a
freshwater stream or canal discharges.
For south Florida EPA is proposing the use of downstream protection
values (DPVs) to manage nitrogen and phosphorus pollution in the inland
flowing waters and protect the water quality of estuaries and coastal
waters downstream. As in estuarine and coastal systems, EPA followed a
series of steps to derive criteria in south Florida inland flowing
waters, including classification of water bodies, segmentation, review
and analysis of biological endpoints, application of analytical
methodologies, and development of DPVs. EPA defined south Florida
inland flowing waters as inland predominantly fresh surface waters that
have been classified as Class I or Class III, which encompasses the
waters south of Lake Okeechobee, the Caloosahatchee River (including
Estero Bay) watershed, and the St. Lucie watershed. EPA segmented south
Florida waters by identifying 22 canal pour points that drain
freshwater to each marine segment. To manage nitrogen and phosphorus
pollution in the inland flowing waters and protect the water quality of
estuaries and coastal waters downstream EPA then screened water quality
data at each pour point to prevent the use of upstream water quality
data that coincided with a documented downstream impact. EPA then
calculated DPVs using the reference condition approach.
In deriving scientifically sound numeric nutrient criteria for this
proposed rulemaking, EPA relied on the local technical expertise of
various scientific experts in Florida. EPA met and consulted with
FDEP's scientific and technical experts during the development of these
numeric nutrient criteria as part of an ongoing collaborative process
to analyze, evaluate, and interpret a substantial amount of Florida-
specific data. EPA carefully evaluated the technical approaches and
scientific analyses that FDEP presented as part of their draft

[[Page 74942]]

approaches to develop numeric nutrient criteria for estuaries within
the State. Finally, EPA also carefully considered substantial
stakeholder input from twelve public hearings conducted by FDEP during
2010, in addition to working with scientists from several Florida
National Estuary Programs (NEPs), Water Management Districts,
universities, and other government agencies in Florida.
To further ensure the best use of available data and scientific
analyses for deriving criteria, the Agency submitted its potential
methods and approaches for an independent, scientific peer review by
EPA's Science Advisory Board (SAB) in November 2010. The SAB reviewed
the document entitled, Methods and Approaches for Numeric Nutrient
Criteria for Nitrogen/Phosphorus Pollution in Florida's Estuaries,
Coastal Waters, and Southern Inland Flowing Waters, and submitted their
final recommendations to EPA in July 2011.\147\ The SAB agreed that a
dual nutrient strategy to derive criteria for both nitrogen and
phosphorus is warranted. The SAB also found that all of the approaches
that EPA proposed for use in this rulemaking (i.e., reference
condition, stressor-response, and mechanistic modeling) have utility
and recommended that a combination of approaches be used where data and
models are available. The SAB provided numerous recommendations to
strengthen the application of the approaches to develop numeric
nutrient criteria for Florida waters that EPA has used to refine the
methods and approaches for deriving the criteria proposed in this
rulemaking.\148\
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\147\ USEPA-SAB. 2011. Review of EPA's Draft Approaches for
Deriving Numeric Nutrient Criteria for Florida's Estuaries, Coastal
Waters, and Southern Inland Flowing Waters. EPA-SAB-11-010. U.S.
Environmental Protection Agency, Science Advisory Board, Washington,
DC.
USEPA. 2010. Methods and Approaches for Deriving Numeric
Criteria for Nitrogen/Phosphorus Pollution in Florida's Estuaries,
Coastal Waters, and Southern Inland Flowing Waters. U.S.
Environmental Protection Agency, Office of Water, Washington, DC.
\148\ EPA response letter to SAB. http://yosemite.epa.gov/sab/
sabproduct.nsf/fedrgstr--activites/DCC3488B67473BDA852578D20058F3C9/
$File/EPA-SAB-11-010--Response--10-26-2011.pdf. Accessed May 2012.
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Section III.A provides an overview of the technical elements used
to support derivation of the numeric nutrient criteria proposed in this
rulemaking for estuaries and coastal waters.\149\ The remainder of
Section III specifically describes EPA's proposed numeric nutrient
criteria for estuaries (Section III.B), coastal waters (Section III.C),
and south Florida inland flowing waters (Section III.D). Also included
are proposed DPVs for estuaries (Section III.B) and south Florida
marine waters (Section III.D).
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\149\ Additional details are provided in a separate document,
the Technical Support Document for U.S. EPA's Proposed Rule for
Numeric Nutrient Criteria for Florida's Estuaries, Coastal Waters,
and Southern Inland Flowing Waters (TSD); located at
www.regulations.gov, Docket ID No. EPA-HQ-OW-2010-0222.
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A. General Information and Approaches

For each group of waters addressed in Section III, EPA is proposing
to use system-specific approaches based on the classification and
segmentation results for each system (described in detail in Sections
III.B, III.C, and III.D) for the derivation of numeric nutrient
criteria to ensure that the diversity of unique ecosystems found in
each type of water body is taken into consideration. This system-
specific approach allows the Agency to consider the physical, chemical,
and biological characteristics of a particular water body and to select
a scientifically defensible approach, considering the data and
information available for each system. This section describes the
technical approaches EPA employed to derive the proposed criteria and
DPVs, including (1) data and segmentation, (2) biological endpoints,
and (3) analytical methodologies.
1. Data Sources and Segmentation
(a) Estuaries
Florida's estuarine areas encompass approximately 1,950 square
miles. EPA used the IWR Run 40 database \150\ to identify available
data from a range of sampling sites in Florida's estuaries. To compute
relationships between nutrient concentrations and chlorophyll a, EPA
relied on measurements of Total Kjeldahl Nitrogen (TKN), TN, Nitrate-
Nitrite (NO3-NO2), TP, and chlorophyll a from the
IWR Run 40 database. The resulting dataset included 180,814 water
quality samples, collected at 13,648 sites. The Agency also analyzed
additional data submitted by local experts and organizations.
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\150\ Florida's IWR data are the chemical, physical and
biological water quality data that FDEP uses to create its
integrated reports. IWR Run 40. Updated through February 2010. FL
IWR and STORET can be found at: http://www.dep.state.fl.us/WATER/STORET/INDEX.HTM.
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The water quality and biological communities of an estuary are
affected by multiple factors related to the shape and size of the
estuary, its connections to the ocean, geology, climate, and watershed
characteristics (e.g., watershed area and land use). Because each of
these factors can vary from one system to another, causing the water
quality and aquatic populations of flora and fauna in each estuary to
be distinct, EPA proposes to classify 19 individual estuarine systems
based on the natural geographic features of estuarine basins and their
associated watersheds. This approach has been utilized previously in
development of the NOAA Coastal Assessment Framework.\151\ This
approach is also consistent with a watershed approach to water quality
management, which EPA encourages as a way to integrate and coordinate
efforts within a watershed in order to most effectively and efficiently
assess conditions and implement controls.\152\
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\151\ NOAA. 2007. NOAA's Coastal Geospatial Data Project,
Coastal Assessment Framework (CAF). NOAA/NOS Special Projects
Office--Coastal Geospatial Data Project. Silver Spring, MD. http://coastalgeospatial.noaa.gov/. Accessed May 2012.
\152\ USEPA. 2008. Handbook for Developing Watershed Plans to
Restore and Protect Our Waters. EPA 841-B-08-002. U.S. Environmental
Protection Agency, Office of Water, Washington DC.
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EPA is proposing to sub-divide each estuarine system into segments
based on physical factors and long-term average salinity gradients.
Estuaries are complex and dynamic systems that reflect the mixing of
fresh and marine water, and different ecological zones correspond to
differences in salinity within each estuary. The estuary segments are
expected to have unique physical, chemical, and biological
characteristics that may respond differently to nutrient inputs than
other segments within the same estuary.\153\ EPA is proposing numeric
nutrient criteria for 89 individual segments in 19 estuaries. A
detailed description and detailed maps of EPA's proposed within-estuary
segments are provided in the TSD (Volume 1: Estuaries, Section 1.3 and
for each estuarine system in Section 2).
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\153\ Telesh, I.V., and V.V. Khlebovich. 2010. Principal
processes within the estuarine salinity gradient: A review. Marine
Pollution Bulletin 61(4-6):149-155.
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(b) Coastal Waters
There are substantial data available from satellite remote sensing
that can be used in a scientifically defensible and reliable way in
conjunction with available field monitoring data to derive numeric
chlorophyll a criteria for coastal waters. Satellite remote sensing
technologies have been widely used \154\ to measure chlorophyll a in
approximately 3,865 square miles of coastal waters in Florida. These
technologies allow consistent and

[[Page 74943]]

reliable monitoring of expansive areas of Florida's coastline.
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\154\ Gregg, W.W., and NW. Casey. 2004. Global and regional
evaluation of the SeaWiFS chlorophyll data set. Remote Sensing of
Environment 93(4):463-479.
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The data EPA used to derive numeric chlorophyll a criteria for
Florida's coastal waters encompass a twelve year period of record
(1998-2009). The length of this data record captures the long-term
variability that has been observed in water quality within Florida's
coastal waters and allows EPA to take advantage of the available remote
sensing data. To obtain chlorophyll a measurements from satellite
remote sensing (chlRS-a), EPA processed data from over 1,000
8-day composites of remotely sensed images from satellite ocean color
data. The eight-day binning period is a standard approach based on the
satellite orbit repeat period of 16 days for the Sea-viewing Wide
Field-of-view Sensor (SeaWiFS) satellite.\155\ EPA also obtained field
monitoring TN, TP, and chlorophyll a data from FDEP IWR Run 40, the
Northeastern Gulf of Mexico Chemical Oceanography and Hydrography Study
(NEGOM), the Ecology and Oceanography of Harmful Algal Blooms Research
Program (ECOHAB), the Florida Fish and Wildlife Conservation Commission
Fish and Wildlife Research Institute (FWRI), NOAA Oceanographic Data
Center (NODC), Mote Marine Laboratory, and the SeaWiFS Bio-optical
Archive and Storage System (SeaBASS). Field monitoring data included
over 5,500 chlorophyll a measurements, which were reduced to 1,947
measurements after screening for data quality, as described later in
this proposed rule.
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\155\ Campbell, J.W., J.M. Blaisdell, and M. Darzi. 1995. Volume
32, Level-3 SeaWiFS Data Products: Spatial and Temporal Binning
Algorithms. In: SeaWiFS Technical Report Series. eds. Hooker, S.B.,
E.R. Firestone, and J.G. Acker. NASA Technical Memorandum 104566,
Vol. 32. National Aeronautics and Space Administration. Greenbelt,
MD.
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EPA is not proposing to derive TN and TP criteria for Florida's
coastal waters due to lack of sufficient field monitoring data for TN
and TP. Although it would be a more reliable indicator to include TN
and TP in combination with chlorophyll a, EPA believes that the
chlorophyll a criteria should protect these Florida waters because
chlorophyll a can be a sensitive biological parameter that would serve
as a signal to the State that nutrient pollution is creating an
imbalance in the natural populations of aquatic flora and fauna in
Florida's coastal waters. Where EPA has not derived criteria for
certain parameters in this proposed rule, due to insufficient
scientific evidence to support a protective threshold for numeric
nutrient criteria (e.g., TN and TP for the majority of Florida's
coastal waters), EPA or the State may consider deriving criteria in the
future for those parameters.
To ensure data quality, EPA screened available field monitoring
data to find samples with, at a minimum, metadata for date, time,
latitude, longitude, and chlorophyll a or light attenuation
information. Where multiple samples of chlorophyll a at different
depths existed, EPA selected the sample closest to the surface in order
to provide a better comparison to the remotely sensed data. The
monitoring sampling times were also compared to the satellite overpass
times. EPA used samples falling within a plus or minus three hour time
window to minimize variability between the sample time and satellite
overpass time. EPA then compared the satellite chlRS-a data
to the field monitored chlorophyll a data. From this assessment EPA
determined that chlRS-a accurately represents chlorophyll a
in coastal waters.
For the purposes of deriving criteria for coastal waters using
remote sensing data, EPA is proposing to exclude chlRS-a
measurements taken during known bloom events of Karenia brevis from the
statistical distribution of coastal data. K. brevis is a dinoflagellate
responsible for red tide. Satellites can detect K. brevis blooms when
cell counts are above 50,000 cells/L. EPA flagged coastal segments with
cell counts greater than 50,000 cells/L during an 8-day composite and
did not include them in the chlRS-a distributions used in
criteria derivation.\156\ In addition, the same segment was flagged one
week prior to and after a bloom detection to provide a temporal buffer
as blooms are transported along the coast. This proposed approach is
consistent with recommendations from the Agency's Science Advisory
Board, which recommended EPA screen out these data points, as they are
likely not representative of reference conditions.\157\ Analyses of
cumulative distributions of chlRS-a show they are minimally
affected by inclusion or removal of observations affected by K. brevis.
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\156\ Heil, C.A., and K.A. Steidinger. 2009. Monitoring,
management, and mitigation of Karenia blooms in the Eastern Gulf of
Mexico. Harmful Algae 8:611-617.
\157\ USEPA-SAB. 2011. Review of EPA's draft Approaches for
Deriving Numeric Nutrient Criteria for Florida's Estuaries, Coastal
Waters, and Southern Inland Flowing Waters. EPA-SAB-11-010. U.S.
Environmental Protection Agency, Science Advisory Board, Washington,
DC.
---------------------------------------------------------------------------

EPA classified Florida's coastal waters into three main areas: The
Florida Panhandle, West Florida Shelf, and Atlantic Coast. These three
coastal areas were subdivided into a total of 71 segments based on
FDEP's Water Body Identification System (WBIDs), physical factors, the
optical properties of the coastal areas, water quality characteristics,
and the jurisdictional limits of the Clean Water Act (i.e., three
nautical mile seaward limit). A detailed description of EPA's data
screening process and a map of the coastal waters are provided in the
TSD (Volume 2: Coastal Waters, Section 1.3).
(c) Request for Comment on Data and Segmentation
EPA believes the proposed data and segmentation approaches provide
a strong foundation for the derivation of numeric nutrient criteria
that will protect the designated uses in Florida's estuaries and
coastal waters. EPA requests comment on all aspects of these
approaches. Additionally, the Agency is soliciting additional relevant
data and information to assist in the derivation of numeric nutrient
criteria. Relevant data and information includes, but is not limited
to: Monitoring data for DO, chlorophyll a, TN, TP, TKN, dissolved
organic nitrogen, dissolved organic phosphorus, dissolved inorganic
nitrogen, dissolved inorganic phosphorus, and NO3-
NO2. EPA also invites comment on the timeframe of the data
used to derive criteria for each of the water body types. In addition,
EPA requests comment on excluding chlRS-a measurements taken
during known bloom events of K. brevis from the statistical
distribution of coastal data. EPA also solicits additional available
scientific data and information that could be used in the derivation of
numeric criteria for nitrogen and phosphorus in coastal waters.
Even though waters were assigned to segments to ensure homogeneity
of water quality across different locations within a segment, EPA
recognizes that limited variability may still exist across locations
within a given segment. EPA also solicits comment on and requests any
additional available information regarding the ability of the proposed
segmentation approaches to account for the unique water quality
conditions that can be found in estuarine and coastal waters throughout
the State. Finally, EPA is proposing to derive numeric nutrient
criteria using a system-specific approach. EPA requests comment on the
spatial scale of the proposed criteria and whether a broader spatial
approach would be more appropriate.
2. Biological Endpoints
When deriving numeric nutrient criteria, it is important to
identify nutrient-sensitive biological endpoints

[[Page 74944]]

relevant to particular estuarine and coastal systems. These biological
endpoints serve as sensitive measures to identify protective
concentrations of TN, TP, and chlorophyll a that, in turn, will support
balanced natural populations of aquatic flora and fauna and protect the
State's designated uses. EPA conducted an extensive evaluation of
available scientific literature to select appropriate biological
endpoints, reviewing over 800 documents. From this review of the latest
scientific knowledge, EPA has determined that maintenance of
seagrasses, maintenance of balanced algal populations, and maintenance
of aquatic life are three sensitive biological endpoints, which can be
measured by water clarity (as it relates to light levels sufficient to
maintain historic depth of seagrass colonization), chlorophyll a, and
DO, respectively, and appropriately used in derivation of numeric
nutrient criteria that protect the State's designated uses from harmful
increases in nitrogen and phosphorus concentrations. The selection of
these biological endpoints was based upon their scientific
defensibility; sensitivity to harmful, adverse effects caused by the
pollutants nitrogen and phosphorus; and the sufficiency of data
available for each.
EPA derived TN, TP, and chlorophyll a criteria to: (1) Maintain
water clarity to achieve seagrass depth of colonization targets, (2)
reduce the risk of phytoplankton blooms, and (3) maintain dissolved
oxygen concentrations sufficient for balanced, natural aquatic life in
Florida's estuaries and coastal waters. As set out more fully in the
following discussion, these three biological endpoints provide a
scientifically defensible basis upon which to derive numeric nutrient
criteria that protect balanced natural populations of aquatic flora and
fauna over the full range of estuarine and coastal conditions across
Florida; waters that achieve these endpoints support designated uses.
(a) Maintenance of Seagrasses
EPA selected the maintenance of seagrasses, as measured by water
clarity to maintain historic depth of seagrass colonization, as one
biological endpoint and corresponding endpoint measure to derive
numeric nutrient criteria for estuaries. Healthy populations of
seagrasses serve as widely recognized indicators of biological
integrity in estuarine systems and, in turn, of balanced natural
populations of aquatic flora and fauna.\158\
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\158\ Ferdie, M., and J.W. Fourqurean. 2004. Responses of
seagrass communities to fertilization along a gradient of relative
availability of nitrogen and phosphorus in a carbonate environment.
Limnology and Oceanography 49(6):2082-2094.
Orth, R.J., T.J.B. Carruthers, W.C. Dennison, C.M. Duarte, J.W.
Fourqurean, K.L. Heck, A.R. Hughes, G.A. Kendrick, W.J. Kenworthy,
S. Olyarnik, F.T. Short, M. Waycott, and S.L. Williams. 2006. A
global crisis for seagrass ecosystems. BioScience 56(12):987-996.
Doren, R.F., J.C. Trexler, A.D. Gottlieb, and M.C. Harwell.
2009. Ecological indicators for system-wide assessment of the
greater everglades ecosystem restoration program. Ecological
Indicators 9:S2-S16.
Gibson, G.R., M.L. Bowman, J. Gerritsen, and B.D. Snyder. 2000.
Estuarine and Coastal Marine Waters: Bioassessment and Biocriteria
Technical Guidance. EPA 822-B-00-024. U.S. Environmental Protection
Agency, Office of Water, Washington, DC. http://water.epa.gov/scitech/swguidance/standards/criteria/aqlife/biocriteria/upload/2009_04_22_biocriteria_States_estuaries_estuaries.pdf.
Accessed November 2011.
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Because of the unique conditions that are created within seagrass
communities, populations of other aquatic floral and faunal species
benefit from the presence and abundance of seagrasses.\159\ For
example, seagrasses act as nurseries for many species by providing
refuge from predators. Seagrasses also improve water quality by
trapping suspended sediments, preventing sediment resuspension, and
retaining nutrients. Florida's NEPs and FDEP have also used endpoints
based on seagrasses to derive their recommended estuarine criteria
because of seagrass sensitivity to nutrient pollution.
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\159\ Orth, R.J., T.J.B. Carruthers, W.C. Dennison, C.M. Duarte,
J.W. Fourqurean, K.L. Heck Jr., A.R. Hughes, G.A. Kendrick, W.J.
Kenworthy, S. Olyarnik, F.T. Short, M. Waycott, and S.L. Williams.
2006. A global crisis for seagrass ecosystems. Bioscience
56(12):987-996.
---------------------------------------------------------------------------

Seagrass communities depend on a variety of physical, chemical, and
biological conditions to thrive. Among these, adequate underwater light
availability (as measured by water clarity) is one critical factor for
seagrass health. The relationship between water clarity and the depth
to which seagrasses grow, known as the depth of colonization, has been
well-documented.\160\ When seagrasses receive sufficient sunlight,
seagrass biomass remains constant or increases over time. Conversely,
when incoming light is blocked by substances in the water column, such
as phytoplankton, suspended solids, or color, seagrass growth slows or
stops. Studies on seagrasses have documented the relationship of
nutrient pollution-related accelerated algal growth to declines in
available light and subsequent declines in seagrass communities.\161\
Since the area within an estuary available for seagrass growth is
partially a function of the total area with enough sunlight at
sufficient depths to sustain growth, as water clarity decreases and
reduces the amount of sunlight that can reach the seagrasses, the
available area for seagrass growth also decreases. Hence, the greater
the water clarity (and associated available light), the deeper the
water that can support seagrass communities and, therefore, the greater
the extent of seagrass coverage.
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\160\ Dennison, W.C. 1987. Effects of light on seagrass
photosynthesis, growth, and depth distribution. Aquatic Botany
27:15-26.
Dennison, W.C., R.J. Orth, K.A. Moore, J.C. Stevenson, V.
Carter, S. Kollar, P.W. Bergstrom, and R.A. Batiuk. 1993. Assessing
water quality with submersed aquatic vegetation. BioScience
43(2):86-94.
Duarte, C.M. 1991. Seagrass depth limits. Aquatic Botany
40(4):363-377.
Gallegos, C.L. 1994. Refining habitat requirements of submersed
aquatic vegetation: Role of optical models. Estuaries 17(1):187-199.
Gallegos, C.L., and W.J. Kenworthy. 1996. Seagrass depth limits
in the Indian River Lagoon (Florida, USA): Application of an optical
water quality model. Estuarine, Coastal and Shelf Science 42(3):267-
288.
Gallegos, C.L. 2005. Optical water quality of a blackwater river
estuary: the Lower St. Johns River, Florida, USA. Estuarine, Coastal
and Shelf Science 63(1-2):57-72.
Steward, J.S., R.W. Virnstein, L.J. Morris, and E.F. Lowe. 2005.
Setting seagrass depth, coverage, and light targets for the Indian
River Lagoon system, Florida. Estuaries and Coasts 28(6):923-935.
\161\ Ferdie, M., and J.W. Fourqurean. 2004. Responses of
seagrass communities to fertilization along a gradient of relative
availability of nitrogen and phosphorus in a carbonate environment.
Limnology and Oceanography 49(6):2082-2094.
Orth, R.J., T.J.B. Carruthers, W.C. Dennison, C.M. Duarte, J.W.
Fourqurean, K.L. Heck, A.R. Hughes, G.A. Kendrick, W.J. Kenworthy,
S. Olyarnik, F.T. Short, M. Waycott, and S.L. Williams. 2006. A
global crisis for seagrass ecosystems. BioScience 56(12):987-996.
---------------------------------------------------------------------------

EPA reviewed studies that empirically assessed the relationship
between seagrass growth and available light \162\ and is proposing
that, for Florida, when an average value of 20 percent of the sunlight
that strikes the water's surface (incident light) reaches the bottom of
the water column (to the depth of seagrass colonization), sufficient
light is available to maintain seagrasses. A similar value has been
used in previous nutrient management efforts in Florida.\163\
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\162\ Dennison, W.C., R.J. Orth, K.A. Moore, J.C. Stevenson, V.
Carter, S. Kollar, P.W. Bergstrom, and R.A. Batiuk. 1993. Assessing
water quality with submersed aquatic vegetation. BioScience
43(2):86-94.
Duarte, C.M. 1991. Seagrass depth limits. Aquatic Botany
40(4):363-377.
Gallegos, C.L. 1994. Refining habitat requirements of submersed
aquatic vegetation: Role of optical models. Estuaries 17(1):187-199.
Steward, J.S., R.W. Virnstein, L.J. Morris, and E.F. Lowe. 2005.
Setting seagrass depth, coverage, and light targets for the Indian
River Lagoon system, Florida. Estuaries and Coasts 28(6):923-935.
\163\ Janicki, A.J., and D.L. Wade. 1996. Estimating critical
external nitrogen loads for the Tampa Bay estuary: An empirically
based approach to setting management targets. Technical Publication
06-96. Prepared for Tampa Bay National Estuary Program, St.
Petersburg, FL, by Coastal Environmental, Inc., St. Petersburg, FL.

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[[Page 74945]]

EPA is also proposing that protecting and maintaining water clarity
sufficient to support an appropriate depth of colonization provides the
greatest protection of balanced natural populations of aquatic flora
and fauna since maintenance of seagrass habitat is critical to
ecosystem conditions. EPA used available historical seagrass coverage
data (including the earliest available, generally 1940-1960, or more
recent, 1992) to compute the historical maximum depth of seagrass
colonization as a reference. In all cases the most recent (2000-2010)
seagrass coverage was also evaluated to determine existing depth of
colonization, and to relate this value to existing water quality. To
compute seagrass depth of colonization, EPA overlaid seagrass coverage
data and bathymetric data compiled by NOAA using a Geographic
Information System.\164\ EPA then used the data on seagrass coverage to
determine the maximum depths that seagrasses have been able to grow in
each estuary, where applicable (this approach was not used in some
estuaries in Florida that do not have historical evidence of seagrass
colonization), in order to identify a reference point for a healthy
level of seagrass colonization. Because seagrass habitats support a
rich array of biological uses,\165\ EPA is proposing to derive numeric
nutrient criteria to maintain a comparable depth of seagrass
colonization to the reference level (i.e. seagrasses growing at the
deepest observed depth of colonization) to ensure protection of
balanced natural populations of aquatic flora and fauna. EPA chose to
use the historical maximum observed depth, and resulting areal
coverage, because increasing nutrients beyond the point that is
protective of maximum coverage of seagrass is likely to cause a decline
in seagrass coverage. Because a wide variety of organisms rely on
healthy seagrass communities, a decrease in seagrass coverage to levels
below the maximum observed depth will result in a decline in overall
system health and biodiversity.\166\ EPA calculated a water clarity
target that would ensure 20% percent of incident light at the surface
would be able to reach the reference depth of colonization. Finally,
EPA used this water clarity target to derive numeric criteria for TN,
TP, and chlorophyll a to support balanced natural populations of
aquatic flora and fauna. (More detail on the importance of seagrass can
be found in the TSD, Volume 1: Estuaries, Section 1.2.1).
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\165\ Hughes, A.R., S.L. Williams, C.M. Duarte, K.L. Heck, Jr.,
and M. Waycott. 2009. Associations of concern: declining seagrasses
and threatened dependent species. Frontiers in Ecology and the
Environment 7(5):242-246.
\166\ Hughes, A.R., S.L. Williams, C.M. Duarte, K.L. Heck, Jr.,
and M. Waycott. 2009. Associations of concern: declining seagrasses
and threatened dependent species. Frontiers in Ecology and the
Environment 7(5):242-246.
Orth, R.J., T.J.B. Carruthers, W.C. Dennison, C.M. Duarte, J.W.
Fourqurean, K.L. Heck, A.R. Hughes, G.A. Kendrick, W.J. Kenworthy,
S. Olyarnik, F.T. Short, M. Waycott, and S.L. Williams. 2006. A
global crisis for seagrass ecosystems. BioScience 56(12):987-996.
FFWCC. 2003. Conserving Florida's Seagrass Resources: Developing
a Coordinated Statewide Management Program. Florida Fish and
Wildlife Conservation Commission, Florida Marine Research Institute.
St. Petersburg, FL.
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(b) Maintenance of Balanced Algal Populations
Based upon EPA's extensive review of current scientific literature,
EPA selected maintenance of balanced algal populations, as measured by
the chlorophyll a concentrations associated with balanced phytoplankton
biomass, as the second biological endpoint and corresponding endpoint
measure to derive numeric nutrient criteria for estuaries and coastal
waters. The maintenance of balanced algal populations is an important
sensitive biological endpoint because of its responsiveness to nutrient
enrichment, integral role in aquatic food webs, well-established use as
an integrative measure of aquatic ecosystem condition, and correlation
with changes in floral composition and subsequent faunal response.\167\
Chlorophyll a is the endpoint measure of balanced algal populations,
and has a long history of use in aquatic ecology as a measure of
phytoplankton biomass and production.\168\ Elevated chlorophyll a
concentrations resulting from nutrient pollution-enhanced algal growth
and accumulation are a well-documented symptom of eutrophication and
the harmful, adverse impacts of nitrogen and phosphorus pollution
across the nation, and specifically in Florida (refer to Section II.A
for additional information).\169\ In most of Florida's coastal and
estuarine waters, healthy biological communities depend on balanced
natural populations of algae because algae are integral components of
aquatic food webs and aquatic nutrient cycling.\170\
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\167\ Boyer, J.N., C.R. Kelble, P.B. Ortner, and D.T. Rudnick.
2009. Phytoplankton bloom status: Chlorophyll a biomass as an
indicator of water quality condition in the southern estuaries of
Florida, USA. Ecological Indicators 9s:S56-S67.
Hagy, J.D., J.C. Kurtz, and R.M. Greene. 2008. An approach for
developing numeric nutrient criteria for a Gulf coast estuary. EPA
600R-08/004. U.S. Environmental Protection Agency, Office of
Research and Development, National Health and Environmental Effects
Research Laboratory, Gulf Breeze, FL.
Bricker, S.B., C.G. Clement, D.E. Pirhalla, S.P. Orlando, and
D.R.G. Farrow. 1999. National Estuarine Eutrophication Assessment.
Effects of Nutrient Enrichment in the Nation's Estuaries. National
Oceanic and Atmospheric Administration, National Ocean Service,
Special Projects Office and the National Centers for Coastal Ocean
Science, Silver Spring, MD.
See Section B.3 in Appendix B of USEPA. 2010. Methods and
Approaches for Deriving Numeric Criteria for Nitrogen/Phosphorus
Pollution in Florida's Estuaries, Coastal Waters, and Southern
Inland Flowing Waters. U.S. Environmental Protection Agency, Office
of Water, Washington, DC.
\168\ Wetzel, R.G. 2001. Limnology: Lakes and River Ecosystems.
3rd ed. Academic Press, San Diego, CA.
Kalff, J. 2002. Limnology: Inland Water Ecosystems. Prentice-
Hall, Inc., Upper Saddle River, New Jersey.
\169\ Elser, J.J., M.E.S. Bracken, E.E. Cleland, D.S. Gruner,
W.S. Harpole, H. Hillebrand, J.T. Ngai, E.W. Seabloom, J.B. Shurin,
and J.E. Smith. 2007. Global analysis of nitrogen and phosphorus
limitation of primary production in freshwater, marine, and
terrestrial ecosystems. Ecology Letters 10:1135-1142.
Smith, V.H. 2006. Responses of estuarine and coastal marine
phytoplankton to nitrogen and phosphorus enrichment. Limnology and
Oceanography 51(1 part 2):377-384
\170\ Hauxwell, J., C. Jacoby, T. Frazer, and J. Stevely. 2001.
Nutrients and Florida's Coastal Waters: The Links Between People,
Increased Nutrients and Changes to Coastal Aquatic Systems. Florida
Sea Grant Report No. SGEB-55. Florida Sea Grant College Program,
University of Florida, Gainesville, FL. http://edis.ifas.ufl.edu/pdffiles/SG/SG06100.pdf. Accessed June 2011.
NOAA. 2011. Overview of Harmful Algal Blooms. National Oceanic
and Atmospheric Administration, Center for Sponsored Coastal
Research. http://www.cop.noaa.gov/stressors/extremeevents/hab/default.aspx. Accessed June 2011.
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Elevated chlorophyll a concentrations resulting from nitrogen and
phosphorus pollution alter the trophic state of estuarine and coastal
waters and increase the frequency and magnitude of algal blooms. EPA
evaluated the available scientific literature to determine chlorophyll
a concentrations indicative of phytoplankton blooms associated with
imbalance in natural populations of aquatic flora and fauna. Published
reports on chlorophyll a concentrations in estuarine waters across the
nation, including Florida estuaries, reflect the range of natural
trophic states and enrichment. These studies suggest that low algal
bloom conditions are defined as maximum chlorophyll a concentrations
less than or equal to 5 [micro]g/L, medium bloom conditions are defined
as maximum chlorophyll a concentrations from greater than 5 to 20
[micro]g/L, high bloom conditions are defined as maximum chlorophyll a
concentrations from greater than 20 to 60 [micro]g/L, and
hypereutrophic conditions are defined by maximum bloom concentrations

[[Page 74946]]

above 60 [micro]g/L.\171\ Two Florida estuaries, Florida Bay and
Pensacola Bay, were analyzed as a part of a larger NOAA national survey
of estuaries. The authors reported the average chlorophyll a
concentrations were 20 [micro]g/L or less for seven of ten large
estuaries nationally, and were especially low for Florida Bay (8
[micro]g/L) and Pensacola Bay (10 [micro]g/L).\172\ Other literature
regarding phytoplankton blooms indicated similar results.\173\
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\171\ Bricker, S.B., J.G. Ferreira, and T. Simas. 2003. An
integrated methodology for assessment of estuarine trophic status.
Ecological Modelling 169(1):39-60.
\172\ Glibert, P.M., C.J. Madden, W. Boynton, D. Flemer, C.
Heil, and J. Sharp, eds. 2010. Nutrients in Estuaries: A Summary
Report of the National Estuarine Experts Workgroup, 2005-2007.
Report to U.S. Environmental Protection Agency, Office of Water,
Washington DC.
\173\ OECD. 1982. Eutrophication of Waters: Monitoring,
Assessment and Control. Organisation for Economic Cooperation and
Development, Paris, France.
Painting, S.J., M.J. Devlin, S.J. Malcolm, E.R. Parker, D.K.
Mills, C. Mills, P. Tett, A. Wither, J. Burt, R. Jones, and K.
Winpenny. 2007. Assessing the impact of nutrient enrichment in
estuaries: susceptibility to eutrophication. Marine Pollution
Bulletin 55:74-90.
Painting, S.J., M.J. Devlin, S.I. Rogers, D.K. Mills, E.R.
Parker, and H.L. Rees. 2005. Assessing the suitability of OSPAR
EcoQOs for eutrophication vs. ICES criteria for England and Wales.
Marine Pollution Bulletin 50:1569-1584.
Tett, P., R. Gowen, D. Mills, T. Fernandes, L. Gilpin, M.
Huxham, K. Kennington, P. Read, M. Service, M. Wilkinson, and S.
Malcolm. 2007. Defining and detecting undesirable disturbance in the
context of marine eutrophication. Marine Pollution Bulletin 55:282-
297.
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Chlorophyll a concentrations associated with hypereutrophic
conditions (>60 [micro]g/L) reflect a trophic state that is unnatural
for Florida estuaries. While some estuaries in the State are more
productive than others, high chlorophyll a concentrations (20 to 60
[micro]g/L) also do not appear to reflect balanced conditions in
Florida, especially given observed ranges in Florida. Concentrations of
chlorophyll a in this high range are associated more frequently with
loss of seagrass and a shift of algal populations to monoculture or, in
other words, a loss in the balance of diverse populations of aquatic
flora.\174\ Moreover, this concentration range was also associated with
conditions where other uses, including recreation, are adversely
affected. Based on the range of chlorophyll a concentrations indicative
of natural algal bloom conditions characteristic of Florida estuaries,
as well as the literature on concentrations associated with harmful,
adverse conditions for estuarine biota and other use support, EPA is
proposing a chlorophyll a concentration of 20 [micro]g/L as the water
quality target to define a nuisance algal bloom. Thus, estuarine waters
with chlorophyll a concentrations that exceed this water quality target
threshold are indicative of imbalanced populations of aquatic flora and
fauna (More detail regarding EPA's analysis can be found in the TSD,
Volume 1: Estuaries, Section 1.2.2).
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\174\ Bricker, S.B., J.G. Ferreira, and T. Simas. 2003. An
integrated methodology for assessment of estuarine trophic status.
Ecological Modelling 169(1):39-60.
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EPA also considered the available scientific research described in
this section to establish an allowable frequency of occurrence of
phytoplankton blooms, represented by chlorophyll a levels greater than
20 [mu]g/L, to further define this endpoint measure. EPA is proposing a
value of 10% as an allowable frequency of occurrence of phytoplankton
blooms, that is, chlorophyll a measurements may not exceed 20 [mu]g/L
more than 10% of the time. This frequency is also consistent with
current nutrient management practices in Florida, such as those
utilized in approved Florida TMDLs.
(c) Maintenance of Aquatic Life
EPA selected maintenance of aquatic life, as measured by the
sufficiency of dissolved oxygen (DO) to maintain aquatic life, as a
third biological endpoint and corresponding endpoint measure to derive
numeric nutrient criteria for estuaries. DO concentrations are a well-
known indicator of the health of estuarine and coastal biological
communities. Aquatic animals including fish, benthic
macroinvertebrates, and zooplankton depend on adequate levels of DO to
survive and grow. These levels may differ depending on the species and
life stage of the organism (e.g., larval, juvenile, and adult).\175\
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\175\ Diaz, R.J. 2001. Overview of hypoxia around the world.
Journal of Environmental Quality 30(2):275-281.
Diaz, R.J., and R. Rosenberg. 2008. Spreading dead zones and
consequences for marine ecosystems. Science 321(5891):926-929.
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To derive the DO endpoint, EPA conducted an analysis of the
dissolved oxygen requirements of sensitive species in Florida using the
Virginian Province dissolved oxygen evaluation procedure.\176\ This
analysis derives DO levels that protect both larval recruitment and
growth for aquatic organisms. EPA used the results of this analysis to
determine the dissolved oxygen water quality targets considered for
numeric nutrient criteria development that would protect sensitive
aquatic species in Florida estuaries. EPA is proposing that satisfying
three different DO requirements in Florida's estuarine waters would
meet the needs of resident sensitive aquatic species, and thus support
the maintenance of aquatic life. These requirements are an
instantaneous DO concentration of 4.0 mg/L, a daily average DO
concentration of 5.0 mg/L, and a bottom water average DO concentration
of 1.5 mg/L. Both the instantaneous minimum of 4.0 mg/L and the daily
average of 5.0 mg/L are spatial averages over the water column for each
estuarine segment. These values and interpretations are consistent with
existing Florida DO criteria (Subsection 62-302.530(30), F.A.C.) and
FDEP's assessment procedures (Subsection 62-303.320(5), F.A.C.). (More
detail on both the existing Florida DO criteria and EPA's analysis can
be found in the TSD, Volume 1: Estuaries, Sections 1.2.3 and 1.4.1).
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\176\ Vincent, A.M., J. Flippin, E. Leppo, and J.D. Hagy III.
Dissolved oxygen requirements of Florida-resident saltwater species
applied to water quality criteria development. In review.
USEPA. 2000. Ambient Aquatic Life Water Quality Criteria for
Dissolved Oxygen (Saltwater): Cape Cod to Cape Hatteras. EPA-822-R-
00-012. U.S. Environmental Protection Agency, Office of Water,
Washington DC.
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(d) Other Endpoints Considered by EPA
EPA considered, but is not proposing to use, the following
nutrient-sensitive biological endpoints: (1) Harmful algal blooms
(HABs), (2) coral, (3) epiphytes, (4) macroinvertebrate and fish
indices, (5) macroalgae, (6) Spartina marshes (salt-marshes), and (7)
the Eastern oyster (Crassostrea virginica). EPA did not select these
biological endpoints because there was an absence of sufficient data to
quantify the link between measurements of these endpoints and nitrogen
and phosphorus concentrations. Additional details on these alternative
endpoints are provided in Appendix B in the Methods and Approaches for
Deriving Numeric Criteria for Nitrogen/Phosphorus Pollution in
Florida's Estuaries, Coastal Waters, and Southern Inland Flowing
Waters.\177\
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\177\ USEPA. 2010. Methods and Approaches for Deriving Numeric
Criteria for Nitrogen/Phosphorus Pollution in Florida's Estuaries,
Coastal Waters, and Southern Inland Flowing Waters. U.S.
Environmental Protection Agency, Office of Water, Washington, DC.
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(e) Request for Commerce on Endpoints
EPA believes that maintenance of seagrasses, maintenance of
balanced algal populations, and maintenance of aquatic life are the
three most appropriate nutrient-sensitive biological endpoints to use
to derive numeric nutrient criteria to ensure that nutrient
concentrations in a body of water

[[Page 74947]]

protect balanced natural populations of aquatic flora and fauna, and in
turn support designated uses. EPA requests comment regarding the
biological endpoints and endpoint measures selected. EPA also solicits
additional scientific information on other appropriate endpoints that
can be used to protect fish consumption, recreation, and the
propagation and maintenance of a healthy, well-balanced population of
fish and wildlife in Florida's Class II and III estuarine and coastal
waters.
3. Analytical Methodologies
EPA used three analytical approaches to derive TN, TP, and
chlorophyll a numeric nutrient criteria for different types of waters
in Florida. In most of Florida coastal waters, EPA is proposing to use
a reference condition approach that utilizes data from waters that
support balanced natural populations of aquatic flora and fauna to
derive numeric nutrient criteria. In Florida estuaries (including some
coastal waters in the Big Bend Coastal region), EPA is proposing to use
statistical and mechanistic models to determine protective
concentrations of TN, TP, and chlorophyll a linked to biological
endpoints. Where sufficient data were not available to apply
statistical models (i.e., stressor-response approach) in all segments
in an estuary, EPA used mechanistic model predictions to derive
criteria. In these instances, EPA analyzed the available stressor-
response analysis as a second line of evidence, in segments where the
data were available.
(a) Reference Condition Approach
EPA is proposing to use the reference condition approach to derive
numeric nutrient criteria in coastal waters that support balanced
natural populations of aquatic flora and fauna. EPA is proposing this
approach to derive numeric chlorophyll a criteria for Florida's coastal
waters because the scientific data and information available were
insufficient to establish accurate quantifiable relationships between
TN and TP concentrations and harmful, adverse effects due to the
limited TN and TP data available. Therefore, EPA is proposing to rely
upon the reference condition approach to identify numeric chlorophyll a
criteria concentrations that protect the designated uses, and avoid any
adverse change in natural populations of aquatic flora or fauna in
Florida's coastal waters.
The reference condition approach, which has been well documented,
peer reviewed, and developed in a number of different contexts,\178\ is
used to derive numeric nutrient criteria that are protective of
applicable designated uses by identifying numeric nutrient criteria
concentrations occurring in least-disturbed, healthy coastal waters
that are supporting designated uses.
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\178\ USEPA. 2000a. Nutrient Criteria Technical Guidance Manual:
Lakes and Reservoirs. EPA-822-B-00-001. U.S. Environmental
Protection Agency, Office of Water, Washington, DC.
USEPA. 2000b. Nutrient Criteria Technical Guidance Manual:
Rivers and Streams. EPA-822-B-00-002. U.S. Environmental Protection
Agency, Office of Water, Washington, DC.
Stoddard, J.L., D.P. Larsen, C.P. Hawkins, R.K. Johnson, and
R.H. Norris. 2006. Setting expectations for the ecological condition
of streams: The concept of reference condition. Ecological
Applications 16:1267-1276.
Herlihy, A.T., S.G. Paulsen, J. Van Sickle, J.L. Stoddard, C.P.
Hawkins, L.L. Yuan. 2008. Striving for consistency in a national
assessment: The challenges of applying a reference-condition
approach at a continental scale. Journal of the North American
Benthological Society 27:860-877.
USEPA. 2001. Nutrient Criteria Technical Manual: Estuarine and
Coastal Marine Waters. EPA-822-B-01-003. U.S. Environmental
Protection Agency, Office of Water, Washington, DC.
USEPA-SAB. 2011. Review of EPA's draft Approaches for Deriving
Numeric Nutrient Criteria for Florida's Estuaries, Coastal Waters,
and Southern Inland Flowing Waters. EPA-SAB-11-010. U.S.
Environmental Protection Agency, Science Advisory Board, Washington,
DC.
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To derive the proposed numeric nutrient criteria using the
reference condition approach, EPA first selected reference conditions
in Florida's coastal waters where the Agency was confident that
designated uses are protected. EPA reviewed available monitoring
information, peer-reviewed literature, and technical reports to ensure
that, where applicable, seagrass beds are healthy, DO is adequate for
sensitive species, phytoplankton biomass is balanced, and that any
other information relating to the ecosystem indicates that the waters
are supporting balanced natural populations of aquatic flora and fauna.
EPA also removed data during periods of temporary known human
disturbances (e.g., bridge and roadway construction) where natural
populations were temporarily affected. Finally, EPA reviewed CWA
section 303(d) listings, and removed data associated with impairment
listings for chlorophyll a, dissolved oxygen, and nutrients, as well as
data from coastal segments adjacent to CWA section 303(d) impaired
estuary waters, such that the resulting data would reflect unimpaired
conditions. EPA only removed data from the period of impairment. The
result of this rigorous analysis was a set of reference waters that,
although not pristine, reflected healthy conditions that were
supporting designated uses, and thus free from harmful, adverse effects
on natural populations of aquatic flora and fauna due to nutrient
pollution. EPA has confidence that these reference waters are
supporting designated uses and balanced natural populations of flora
and fauna, and has confidence that if the criteria are attained or
maintained at the concentrations that are among the highest observed in
these waters, then designated uses and natural populations of aquatic
flora and fauna will be protected in coastal waters. Further details
regarding data screening can be found in the TSD (Volume 2: Coastal
Waters, Section 1.4).
After selecting the reference waters, EPA calculated the annual
geometric mean concentrations of chlorophyll a for each year of the
data record and for each segment.\179\ EPA then calculated a normal
distribution based on the annual geometric mean chlorophyll a
concentrations. From this distribution, which represents the population
of water quality observations in each segment, EPA selected the 90th
percentile as the applicable criteria for each segment. EPA selected
the 90th percentile as an appropriate concentration to specify the
criterion-magnitude because the Agency is confident that the
distribution reflects minimally-impacted, biologically healthy
reference conditions, which support the State's Class II and III
designated uses. The use of the 90th percentile of chlorophyll a is
also supported by several eutrophication assessment frameworks in
Europe and the U.S, such as the Oslo-Paris Commission ``Common
Procedure'' (OSPAR), Water Framework Directive of the EU, Assessment of
Estuarine Trophic Status in the US, and the Marine Strategy Framework
Directive used by the European Commission, which identify the 90th
percentile as representative of a chlorophyll a concentration above
which eutrophication is considered ecologically problematic or where an
undesirable disturbance to aquatic life and water quality from
eutrophication are highly likely to appear.\180\ For

[[Page 74948]]

further information on the use of the reference approach see the TSD
(Volume 2, Coastal Waters, Section 1.5.1).
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\179\ Geometric means were used for averages in the reference
condition, statistical modeling, and mechanistic modeling approaches
because concentrations were log-normally distributed.
\180\ OSPAR Commission. 2005. Common Procedure for the
Identification of the Eutrophication Status of the OSPAR Maritime
Area (Reference Number: 2005-3). OSPAR Commission, London.
Ferreira, J.G., J.H. Andersen, A. Borja, S.B. Bricker, J. Camp,
M.C. da Silva, E. Garc[eacute]s, A-S. Heiskanen, C. Humborg, L.
Ignatiades, C. Lancelot, A. Menesguen, P. Tett, N. Hoepffner, and U.
Claussen. 2011. Overview of eutrophication indicators to assess
environmental status within the European Marine Strategy Framework
Directive. Estuarine, Coastal and Shelf Science 93(2):117-131.
Bricker, S.B., J.G. Ferreira, and T. Simas. 2003. An integrated
methodology for assessment of estuarine trophic status. Ecological
Modelling 169:39-60.
European Commission. 2003. Common Implementation Strategy for
the Water Framework Directive (2000/60/EC): Guidance Document No. 5,
Transitional and Coastal Waters-Typology, Reference Conditions and
Classification Systems. European Commission, Working Group 2.4--
COAST, Office for Official Publications of the European Communities,
Luxembourg.
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EPA chose not to select the extreme upper end of the distribution
(95th or 100th percentile). This is because these highest observed
annual average concentrations (i.e., 95th or 100th percentile) have
rarely been observed at any reference site and are most likely to be
heavily influenced by extreme event factors (e.g., hurricanes,
droughts). Thus these highest observed concentrations could be outliers
that are not representative of conditions that would typically support
designated uses and natural populations of aquatic flora and fauna.
Therefore, EPA has less confidence that such highest observed
concentrations would continue to be supportive of designated uses and
natural populations of aquatic flora and fauna if maintained in all
coastal waters at all times.
Alternatively, the selection of a much lower percentile, such as a
representation of the central tendency of the distribution (i.e., 50th
percentile), would not be appropriate because it would imply that half
of the conditions observed at reference sites would not support
designated uses and natural populations of aquatic flora and fauna,
when EPA's analysis indicates that they do. By setting the criteria at
the 90th percentile of the reference condition distribution, EPA
believes the designated uses, i.e., natural populations of aquatic
flora and fauna, will be protected when these concentrations are
attained for the majority of coastal water segments. For those coastal
water segments that are shown to accommodate or require higher or lower
concentrations, the SSAC provision is provided in EPA's proposed rule
as discussed in Section V.C.
(b) Statistical Modeling
EPA evaluated the data available for each estuary segment in terms
of temporal and spatial representativeness to establish whether there
were sufficient data to use a statistical model. Where enough
monitoring data in estuaries were available, EPA developed statistical
models (i.e., stressor-response relationships) \181\ that quantified
relationships between TN, TP, chlorophyll a, and the selected endpoint
measures (i.e., water clarity to maintain maximum depth of seagrass
colonization and chlorophyll a concentrations associated with balanced
phytoplankton biomass). There were not enough temporally-resolved DO
monitoring data, particularly in pre-dawn hours when dissolved oxygen
concentrations are typically lower than during that day,\182\ in any of
the estuaries to permit the use of statistical models to derive
criterion values associated with sufficient DO to support aquatic life.
Where the available endpoints were shown to be sufficiently sensitive,
EPA used these relationships to calculate TN, TP, and chlorophyll a
concentrations that achieved the selected water quality targets for
these endpoints, which serve as measures of balanced natural
populations of aquatic flora and fauna.
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\181\ USEPA. 2010. Using stressor-response relationships to
derive numeric nutrient criteria. EPA-820-S-10-001. U.S.
Environmental Protection Agency, Office of Water, Office of Science
and Technology, Washington, DC.
\182\ D'Avanzo, C., and J.N. Kremer. 1994. Diel Oxygen Dynamics
and Anoxic Events in an Eutrophic Estuary of Waquoit Bay,
Massachusetts. Estuaries and Coasts 17(1B):131-139.
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To determine chlorophyll a concentrations supportive of the water
clarity depth target to achieve the healthy seagrass endpoint in a
segment, EPA estimated the relationship between annual geometric mean
chlorophyll a concentrations and annual geometric mean water clarity
for each segment. Then, EPA computed the chlorophyll a criterion as the
chlorophyll a concentration that was associated with the water clarity
target. In other words, the chlorophyll a criterion was determined such
that the water quality target for water clarity was achieved on an
annual average basis.\183\ In some segments, increased annual geometric
mean chlorophyll a concentrations were not associated with decreased
annual geometric mean water clarity, possibly because other factors,
such as suspended sediment or colored dissolved organic material, more
strongly affected water clarity.\184\ In these segments, EPA determined
that the water clarity endpoint was not sufficiently sensitive to
increased chlorophyll a, and therefore, this endpoint was not used to
derive a chlorophyll a criterion, and associated TN and TP criteria in
that segment.
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\183\ Dennison, W.C. 1987. Effects of light on seagrass
photosynthesis, growth, and depth distribution. Aquatic Botany
27:15-26.
\184\ Gallegos, C.L. 2005. Optical water quality of a blackwater
river estuary: the Lower St. Johns River, Florida, USA. Estuarine,
Coastal and Shelf Science 63(1-2):57-72.
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EPA also used stressor-response relationships to derive chlorophyll
a criteria to maintain balanced algal populations. To this end, EPA
used logistic regression to estimate the relationship between annual
geometric mean chlorophyll a concentrations and the probability of any
single chlorophyll a measurement exceeding EPA's proposed water quality
target of 20 [micro]g/L during the year. Then, EPA derived a
chlorophyll a criterion from this relationship by selecting the annual
geometric mean chlorophyll a concentration that ensured that any single
chlorophyll a measurement would not exceed 20 [micro]g/L more than 10%
of the time.
After calculating chlorophyll a candidate criteria values necessary
to meet the water quality targets for the two biological endpoints for
which data were available (maintenance of seagrasses and maintenance of
balanced algal populations), in each water body segment, EPA selected
the more stringent of the two as the proposed criterion for that
segment to ensure that the proposed chlorophyll a criterion would
protect both endpoints.
To calculate TN and TP criteria associated with the chlorophyll a
criterion, EPA estimated the relationship between annual geometric mean
TN and TP concentrations and annual geometric mean chlorophyll a
concentrations for each segment. EPA then used these relationships to
compute the TN and TP concentrations that were required to maintain
average chlorophyll a concentrations at the chlorophyll a criterion. In
some estuary segments, increased TN or TP concentrations were not
associated with increased chlorophyll a concentrations, possibly
because of differences in the proportion of TP or TN that was composed
of biologically unavailable forms of phosphorus or nitrogen, or because
of unique physical or hydrological characteristics of the estuary
segment.\185\ In these segments, EPA determined that chlorophyll a
concentrations were not sufficiently sensitive to increases in TN or TP
concentrations, and therefore, this approach was not used to derive
criteria for these segments.
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\185\ USEPA. 2001. Nutrient Criteria Technical Manual: Estuarine
and Coastal Marine Waters. EPA-822-B-01-003. U.S. Environmental
Protection Agency, Office of Water, Washington, DC.

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[[Page 74949]]

In instances where one of the endpoints was not sufficiently
sensitive to increases in TN or TP concentrations the relationship of
the other endpoint to TN or TP was examined. If both endpoints were
insensitive to TN or TP, then the statistical models were not used to
derive candidate criteria for the particular nutrient.
In a limited number of estuary segments, EPA found that the TN, TP,
or chlorophyll a concentrations that were associated with achieving the
water quality targets for the biological endpoints were outside
(greater than or less than) the range of TN, TP, or chlorophyll a
concentrations observed in the available data for the estuary. In other
words, in these situations, using statistical models to derive numeric
nutrient criteria would require EPA to extrapolate the TN, TP, and
chlorophyll a relationships beyond the range of available data. Because
of the uncertainty inherent in conducting such extrapolations, EPA is
proposing instead to set numeric nutrient criteria derived from these
statistically modeled relationships at the 90th percentile or 10th
percentile limit of the distribution of available data instead of
deriving criteria outside the range of data observations.\186\ For
example, if the statistically modeled value for TP associated with
achieving all water quality targets to meet the biological endpoints in
an estuary segment was less than the 10th percentile of annual average
values of TP observed in that segment, EPA is proposing to set the
criterion value at the 10th percentile of annual average values of TP.
This approach defines criterion values that maintain balanced natural
populations of aquatic flora and fauna within the limits of available
data and is consistent with EPA's reasoning for the selection of the
90th percentile when using the reference condition approach. EPA
requests comment on whether to extrapolate stressor-response
relationships beyond the range of available data. For further
information on the use of statistical modeling approach, see the TSD
(Volume 1: Estuaries, Section 1.4.2 and Appendix B).
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\186\ USEPA. 2010. Using Stressor-response Relationships to
Derive Numeric Nutrient Criteria. EPA-820-S-10-001. U.S.
Environmental Protection Agency, Office of Water, Washington, DC.
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(c) Mechanistic Modeling
EPA also quantified relationships between nitrogen and phosphorus
loads and the three biological endpoints using a coupled system of
watershed models and estuarine hydrodynamic and water quality models.
These models simulated the physical, chemical, and biological processes
in a watershed-estuarine system. EPA first used the watershed models to
develop estimates of TN, TP, and freshwater inputs to the estuary.
Next, EPA used the estuarine hydrodynamic and water quality models to
simulate estuarine water quality responses to the watershed inputs,
including changes in estuarine TN, TP, and chlorophyll a
concentrations, water clarity, and DO. Then, EPA utilized these models
to determine concentrations of TN and TP that would protect the most
nutrient-sensitive biological endpoint to derive the numeric nutrient
criteria.
To select the appropriate models, EPA developed an inventory of
watershed and estuary models that have been applied previously to
estuaries in Florida, including models developed by FDEP.\187\ Based on
the results of the review, EPA selected the Loading Simulation Program
in C++ (LSPC) \188\ to simulate freshwater flows and nutrient loading
from watersheds, the Environmental Fluid Dynamics Code (EFDC) \189\ to
simulate estuarine hydrodynamics, and the Water Quality Analysis
Simulation Program (WASP) \190\ to simulate estuarine water
quality.\191\
---------------------------------------------------------------------------

\187\ Wolfe, S.H. 2007. An Inventory of Hydrodynamic, Water
Quality, and Ecosystem Models of Florida Coastal and Ocean Waters.
Florida Department of Environmental Protection, Tallahassee,
Florida.
\188\ USEPA. 2011. Loading Simulation Program in C++ (LSPC).
http://www.epa.gov/athens/wwqtsc/html/lspc.html. Accessed December
2011.
\189\ USEPA. 2011. Environmental Fluid Dynamics Code (EFDC).
http://www.epa.gov/athens/wwqtsc/html/efdc.html. Accessed December
2011.
\190\ USEPA. 2011. Water Quality Analysis Simulation Program
(WASP). http://www.epa.gov/athens/wwqtsc/html/wasp.html. Accessed
December 2011.
\191\ USEPA. 2010. Methods and Approaches for Deriving Numeric
Criteria for Nitrogen/Phosphorus Pollution in Florida's Estuaries,
Coastal Waters, and Southern Inland Flowing Waters. U.S.
Environmental Protection Agency, Office of Water, Washington, DC.
---------------------------------------------------------------------------

LSPC can continuously simulate the hydrologic and water quality
processes on pervious and impervious land surfaces, in streams, and in
well-mixed impoundments throughout the watershed and can provide daily
estimates of stream flow, TN, and TP concentrations entering the
estuary. In addition, LSPC is publicly available and has been peer
reviewed.\192\ LSPC has been successfully applied for water quality
management purposes to many watersheds throughout the southeastern
United States and Florida. Therefore, EPA is proposing to apply the
LSPC model to the watersheds in Florida outside of the South Florida
Nutrient Watershed Region.
---------------------------------------------------------------------------

\192\ USEPA-SAB. 2011. Review of EPA's draft Approaches for
Deriving Numeric Nutrient Criteria for Florida's Estuaries, Coastal
Waters, and Southern Inland Flowing Waters. EPA-SAB-11-010. U.S.
Environmental Protection Agency, Science Advisory Board, Washington,
DC.
---------------------------------------------------------------------------

EFDC and WASP have been applied in conjunction to simulate
hydrodynamics and water quality (respectively) for many water quality
management projects throughout the southeastern United States and
Florida. EFDC and WASP are also publicly available and have undergone
peer review.\193\ Based on the extensive use of these models for
similar applications and their acceptance in the scientific community,
EPA is proposing to use the EFDC and WASP models to derive numeric
nutrient criteria for Florida's estuaries.
---------------------------------------------------------------------------

\193\ USEPA-SAB. 2011. Review of EPA's draft Approaches for
Deriving Numeric Nutrient Criteria for Florida's Estuaries, Coastal
Waters, and Southern Inland Flowing Waters. EPA-SAB-11-010. U.S.
Environmental Protection Agency, Science Advisory Board, Washington,
DC.
---------------------------------------------------------------------------

For estuaries where monitoring data were insufficient to calculate
criteria using the statistical models, EPA mechanistically modeled the
conditions in each system and corresponding watershed that occurred
from 2002-2009 using all available, screened data. EPA evaluated data
over the historic period of record and is proposing to use 2002 through
2009 as a representative modeling period because complete, continuous
flow and water quality data were available. This period also reflects
the range of hydrology and meteorology observed over the historic
period of record across the Florida estuaries.
EPA then used relationships between TN, TP, and biological
endpoints quantified by the mechanistic models to derive numeric
nutrient criteria. That is, EPA determined the concentrations of TN and
TP that were associated with meeting all biological endpoints in each
segment.
Because estuaries differ in their physical, chemical, and
hydrological characteristics, EPA expected that differences would exist
in the degree to which different biological endpoints respond to
changes in nutrient concentration. For example, in certain estuaries,
high concentrations of colored dissolved organic material (CDOM) occur
naturally and reduce water clarity. Because of the influence of CDOM in
these estuarine systems, changes in TN, TP, and chlorophyll a are not
strongly associated with changes in water clarity. In these systems,
the water clarity endpoint does not appear to be sensitive to changes
in nutrients,

[[Page 74950]]

and therefore, the water clarity endpoint does not provide useful
information for the purposes of deriving numeric nutrient criteria in
these systems. In each estuarine system, EPA used output from
mechanistic models and available monitoring data to evaluate the
sensitivity of each endpoint measure to changes in nutrients. This
analysis was used to determine which endpoints were most critical to
determine protective nutrient concentrations. Endpoints that were found
to be insensitive to changes in nutrient concentrations in a particular
estuarine system were not considered further in deriving numeric
nutrient criteria for a system. Numeric nutrient criteria for each
system were based on the modeled scenario in which the remaining
endpoint measures were met during the modeled period, calculated as
annual geometric means for each year during the modeled period.
Criteria were calculated using the 90th percentile of the annual
geometric means from the modeled years for the model scenario meeting
all appropriate endpoints. EPA selected the 90th percentile to account
for natural variability in the data to represent the upper bound of
conditions supporting designated uses. The selection of the 90th
percentile is appropriate for the same reasons as when using the
reference condition approach. For further information on the use of the
mechanistic modeling approach, see the TSD (Volume 1: Estuaries,
Section 1.4.1).
(d) Request for Comment on Analytical Methodologies
EPA believes that the three proposed analytical methodologies used
in combination result in numeric nutrient criteria that are supportive
of balanced natural populations of aquatic flora and fauna, and thus
protect Class II and III estuarine and coastal waters in the State of
Florida from nutrient pollution. These analytical methodologies
utilized the latest scientific knowledge, nutrient sensitive endpoints,
and the best available data. The Agency requests comment on the
application of the proposed methodologies and whether these
methodologies are appropriate to derive criteria protective of
designated uses in Florida's estuaries and coastal waters.
Specifically, EPA is soliciting comment and any scientific information
on the use of these approaches in areas where there may be other
factors present in addition to nutrients that may also affect the three
biological endpoints by attenuating light in similar ways as
chlorophyll a (e.g., colored dissolved organic matter (CDOM) or
suspended sediments). EPA is also requesting comment on the procedures
used to screen data to identify reference conditions that are
supporting balanced natural populations of aquatic flora and fauna.

B. Proposed Numeric Criteria for Estuaries

1. Introduction
EPA is proposing to use a system-specific approach to derive
numeric nutrient criteria for estuaries to ensure that the unique
physical, chemical, and biological characteristics of each estuarine
ecosystem are taken into consideration.\194\
---------------------------------------------------------------------------

\194\ USEPA. 2001. Nutrient Criteria Technical Manual: Estuarine
and Coastal Marine Waters. EPA-822-B-01-003. U.S. Environmental
Protection Agency, Office of Water, Washington, DC. Glibert, P.M.,
C.J. Madden, W. Boynton, D. Flemer, C. Heil, and J. Sharp, eds.
2010. Nutrients in Estuaries: A Summary Report of the National
Estuarine Experts Workgroup, 2005-2007. Report to U.S. Environmental
Protection Agency, Office of Water, Washington DC.
---------------------------------------------------------------------------

2. Proposed Numeric Criteria (Estuaries)
EPA is proposing numeric TN, TP, and chlorophyll a criteria for 89
discrete segments within 19 estuarine systems in Florida (Table III.B-
1). These include Class II and III waters under Florida law (Section
62-302.400, F.A.C.); EPA did not find any Class I estuarine waters in
Florida. The 19 estuaries include seven systems in the Florida
Panhandle region, four systems in the Big Bend region, and eight
systems along the Atlantic coast. Maps showing the locations of these
estuarine systems and EPA's proposed within-estuary segments are
provided in the TSD (Volume 1: Estuaries, Section 1.3 and Section 2).
In some areas a gap may exist between maps used by Florida and EPA
to show where criteria apply. In areas where a gap exists between EPA's
proposed criteria and Florida's numeric criteria, EPA proposes that
Florida's numeric criteria from the adjacent estuary or marine segment
apply (see Section 62-302.532, F.A.C. for values). EPA proposes that
Florida's criteria from the northernmost segment of Clearwater Harbor/
St Joseph Sound (Subsection 62-302.532(a)1., F.A.C.) apply to the
waters between that segment and the southernmost segment of EPA's
Springs Coast estuary system. EPA proposes that Florida's numeric
criteria from the northernmost segment of Biscayne Bay (Subsection 62-
302.532(h)5., F.A.C.) apply to the waters of the intercoastal waterway
between that segment and the southernmost segment of EPA's Lake Worth
Lagoon estuary system.
In other areas a gap may exist within estuaries covered by
Florida's numeric criteria. In these areas, EPA proposes that Florida's
criteria from the adjacent estuary or marine segment to the south apply
to that gap. EPA proposes that Florida's criteria from (1) the upper
Lemon Bay segment (Subsection 62-302.532(d)2., F.A.C.) apply to the
segment between the upper Lemon Bay segment and the Dona/Roberts Bay
segment (Subsection 62-302.532(d)1., F.A.C.), (2) the Tidal Cocohatchee
River segment (Subsection 62-302.532(e)1., F.A.C.) apply to the waters
between the Tidal Cocohatchee River segment and the Estero Bay segment
(Subsection 62-302.532(d)9., F.A.C.), (3) the Clam Bay segment
(Subsection 62-302.532(j)., F.A.C.) apply between the Clam Bay segment
and the Tidal Cocohatchee River segment (Subsection 62-302.532(e)1.,
F.A.C.), and (4) the Naples Bay segment (Subsection 62-302.532(e)4.,
F.A.C.) apply to the segment between the Naples Bay segment and the
Clam Bay Segment (Subsection 62-302.532(j)., F.A.C.). For further
information regarding the derivation and protectiveness of Florida's
criteria, see http://water.epa.gov/lawsregs/rulesregs/florida_index.cfm.

Table III.B-1--EPA's Proposed Numeric Criteria for Florida's Estuaries
[In geographic order from northwest to northeast]
----------------------------------------------------------------------------------------------------------------
Proposed Criteria
-----------------------------------------------
Segment Segment ID Chl-a* ([mu]g/
TN* (mg/L) TP* (mg/L) L)
----------------------------------------------------------------------------------------------------------------
Perdido Bay:
Upper Perdido Bay........................... 0101 0.59 0.042 5.2

[[Page 74951]]

Big Lagoon.................................. 0102 0.26 0.019 4.9
Central Perdido Bay......................... 0103 0.47 0.031 5.8
Lower Perdido Bay........................... 0104 0.34 0.023 5.8
Pensacola Bay:
Blackwater Bay.............................. 0201 0.53 0.022 3.9
Upper Escambia Bay.......................... 0202 0.43 0.025 3.7
East Bay.................................... 0203 0.50 0.021 4.2
Santa Rosa Sound............................ 0204 0.34 0.018 4.1
Lower Escambia Bay.......................... 0205 0.44 0.023 4.0
Upper Pensacola Bay......................... 0206 0.40 0.021 3.9
Lower Pensacola Bay......................... 0207 0.34 0.020 3.6
Santa Rosa Sound............................ 0208 0.33 0.020 3.9
Santa Rosa Sound............................ 0209 0.36 0.020 4.9
Choctawhatchee Bay:
Eastern Choctawhatchee Bay.................. 0301 0.47 0.025 8.1
Central Choctawhatchee Bay.................. 0302 0.36 0.019 3.8
Western Choctawhatchee Bay.................. 0303 0.21 0.012 2.4
St. Andrews Bay:
East Bay.................................... 0401 0.31 0.014 4.6
St. Andrews Sound........................... 0402 0.14 0.009 2.3
Eastern St. Andrews Bay..................... 0403 0.24 0.021 3.9
Western St. Andrews Bay..................... 0404 0.19 0.016 3.1
Southern St. Andrews Bay.................... 0405 0.15 0.013 2.6
North Bay 1................................. 0406 0.22 0.012 3.7
North Bay 2................................. 0407 0.22 0.014 3.7
North Bay 3................................. 0408 0.21 0.016 3.4
West Bay.................................... 0409 0.23 0.022 3.8
St. Joseph Bay:
St. Joseph Bay.............................. 0501 0.25 0.018 3.8
Apalachicola Bay:
St. George Sound............................ 0601 0.53 0.019 3.6
Apalachicola Bay............................ 0602 0.51 0.019 2.7
East Bay.................................... 0603 0.76 0.034 1.7
St. Vincent Sound........................... 0605 0.52 0.016 11.9
Apalachicola Offshore....................... 0606 0.30 0.008 2.3
Alligator Harbor:
Alligator Harbor............................ 0701 0.36 0.011 2.8
Alligator Offshore.......................... 0702 0.33 0.009 3.1
Alligator Offshore.......................... 0703 0.33 0.009 2.9
Ochlockonee Bay\+\:
Ochlockonee-St. Marks Offshore.............. 0825 0.79 0.033 2.7
Ochlockonee Offshore........................ 0829 0.47 0.019 1.9
Ochlockonee Bay............................. 0830 0.66 0.037 1.8
St. Marks River Offshore.................... 0827 0.51 0.022 1.7
St. Marks River............................. 0828 0.55 0.030 1.2
Big Bend/Apalachee Bay\+\:
Econfina Offshore........................... 0824 0.59 0.028 4.6
Econfina.................................... 0832 0.55 0.032 4.4
Fenholloway................................. 0822 1.15 0.444 1.9
Fenholloway Offshore........................ 0823 0.48 0.034 10.3
Steinhatchee-Fenholloway Offshore........... 0821 0.40 0.023 4.1
Steinhatchee River.......................... 0819 0.67 0.077 1.0
Steinhatchee Offshore....................... 0820 0.34 0.018 3.5
Steinhatchee Offshore....................... 0818 0.39 0.032 4.8
Suwannee River\+\:
Suwannee Offshore........................... 0817 0.78 0.049 5.2
Springs Coast\+\:
Waccasassa River Offshore................... 0814 0.38 0.019 3.9
Cedar Keys.................................. 0815 0.32 0.019 4.1
Crystal River............................... 0812 0.35 0.013 1.3
Crystal-Homosassa Offshore.................. 0813 0.36 0.013 2.1
Homosassa River............................. 0833 0.47 0.032 1.9
Chassahowitzka River........................ 0810 0.32 0.010 0.7
Chassahowitzka River Offshore............... 0811 0.29 0.009 1.7
Weeki Wachee River.......................... 0808 0.32 0.010 1.6
Weeki Wachee Offshore....................... 0809 0.30 0.009 2.1
Pithlachascotee River....................... 0806 0.50 0.022 2.4
Pithlachascotee Offshore.................... 0807 0.32 0.011 2.5

[[Page 74952]]

Anclote River............................... 0804 0.48 0.037 4.7
Anclote Offshore............................ 0805 0.31 0.011 3.2
Anclote Offshore South...................... 0803 0.29 0.008 2.6
----------------------------------------------------------------------------------------------------------------
Clearwater Harbor/St. Joseph Sound: See Section 62-302.532(1)(a) F.A.C.
----------------------------------------------------------------------------------------------------------------
Tampa Bay: See Section 62-302.532(1)(b) F.A.C.
----------------------------------------------------------------------------------------------------------------
Sarasota Bay: See Section 62-302.532(1)(c) F.A.C.
----------------------------------------------------------------------------------------------------------------
Charlotte Harbor/Lemon Bay: See Section 62-302.532(1)(d) F.A.C.
----------------------------------------------------------------------------------------------------------------
Lake Worth Lagoon/Loxahatchee:
North Lake Worth Lagoon..................... 1201 0.55 0.067 4.7
Central Lake Worth Lagoon................... 1202 0.57 0.089 5.3
South Lake Worth Lagoon..................... 1203 0.48 0.034 3.6
Lower Loxahatchee........................... 1301 0.68 0.028 2.7
Middle Loxahatchee.......................... 1302 0.98 0.044 3.9
Upper Loxahatchee........................... 1303 1.25 0.072 3.6
St. Lucie:
Lower St. Lucie............................. 1401 0.58 0.045 5.3
Middle St. Lucie............................ 1402 0.90 0.120 8.4
Upper St. Lucie............................. 1403 1.22 0.197 8.9
Indian River Lagoon:
Mosquito Lagoon............................. 1501 1.18 0.078 7.5
Banana River................................ 1502 1.17 0.036 5.7
Upper Indian River Lagoon................... 1503 1.63 0.074 9.2
Upper Central Indian River Lagoon........... 1504 1.33 0.076 9.2
Lower Central Indian River Lagoon........... 1505 1.12 0.117 8.7
Lower Indian River Lagoon................... 1506 0.49 0.037 4.0
Halifax River:
Upper Halifax River......................... 1601 0.75 0.243 9.4
Lower Halifax River......................... 1602 0.63 0.167 9.6
Guana, Tolomato, Matanzas, Pellicer:
Upper GTMP.................................. 1701 0.77 0.144 9.5
Lower GTMP.................................. 1702 0.53 0.108 6.1
Lower St. Johns River:
Lower St. Johns River....................... 1801 0.75 0.095 2.5
Trout River................................. 1802 1.09 0.108 3.6
Trout River................................. 1803 1.15 0.074 7.7
Nassau River:
Lower Nassau................................ 1901 0.33 0.113 3.2
Middle Nassau............................... 1902 0.40 0.120 2.4
Upper Nassau................................ 1903 0.75 0.125 3.4
St. Marys River:
Lower St. Marys River....................... 2002 0.27 0.045 3.0
Middle St. Marys River...................... 2003 0.44 0.036 2.7
----------------------------------------------------------------------------------------------------------------
\1\ Chlorophyll a is defined as corrected chlorophyll, or the concentration of chlorophyll a remaining after the
chlorophyll degradation product, phaeophytin a, has been subtracted from the uncorrected chlorophyll a
measurement.
* For a given water body, the annual geometric mean of TN, TP, or chlorophyll a, concentrations shall not exceed
the applicable criterion concentration more than once in a three-year period.
\+\ In these four areas (collectively referred to as the ``Big Bend region''), coastal and estuarine waters are
combined. Criteria for the Big Bend region apply to the coastal and estuarine waters in that region.

(a) Summary of Approaches (Estuaries)
(1) Proposed Approach (Estuaries)
In estuaries where sufficient monitoring data were available to
statistically quantify relationships between TN, TP, chlorophyll a, and
biological endpoints, and the endpoints available to derive criteria
were shown to be sufficiently sensitive (i.e., Choctawhatchee Bay; St.
Joseph Bay; Suwannee River; Indian River Lagoon; Halifax River; and the
Guana, Tolomato, Matanzas, and Pellicer (GTMP) estuarine system),
statistical models were used to derive the proposed numeric nutrient
criteria. In three of the estuaries, Choctawhatchee Bay, St. Joseph
Bay, and Indian River Lagoon, there were sufficient available data for
water clarity associated with historic depth of seagrasses, and
chlorophyll a concentrations associated with balanced phytoplankton
biomass targets, and these biological endpoints were sensitive to
changes in nutrients in most segments, so proposed criteria were
derived that were protective of these endpoints. In the Suwannee River,
the water clarity endpoint was not sensitive to changes in nutrients,
so proposed criteria were derived that were protective of the
chlorophyll a target

[[Page 74953]]

associated with balanced phytoplankton biomass. In the Halifax River
and GTMP, seagrass has not been historically present, so the proposed
criteria were derived that are protective of the chlorophyll a target
associated with balanced phytoplankton biomass.
In all other estuaries mechanistic models were used to quantify the
relationship between nutrient loads and biological endpoints. EPA then
used the models to derive proposed numeric nutrient criteria that
protect the endpoints. For each estuary, the endpoints that were shown
to be sufficiently sensitive to nutrient changes above non-
anthropogenic nutrient levels were used, as described in Section
III.A.3.c. The endpoints for each of the estuaries where mechanistic
models were used to derive criteria are noted in the following
discussion.
In Perdido Bay, Apalachicola Bay, three segments in Lake Worth
Lagoon/Loxahatchee (Lake Worth Lagoon, segments 1201, 1202, and 1203),
and St. Lucie, all three biological endpoints were found to be
sensitive to changes to nutrients, and so proposed criteria were
derived that were protective of historic depth of seagrasses (water
clarity), chlorophyll a concentrations associated with balanced
phytoplankton biomass, and dissolved oxygen concentrations sufficient
to maintain aquatic life.
In St. Andrews Bay, 2 segments in the Springs Coast (Anclote River/
Anclote Offshore, segments 0804 and 0805) and 3 segments in Lake Worth
Lagoon/Loxahatchee (Lower, Middle, and Upper Loxahatchee, segments
1301, 1302, and 1303), dissolved oxygen concentrations were found to be
insensitive to changes in nutrients. Proposed criteria were derived
that were protective of historic depth of seagrasses (water clarity)
and chlorophyll a concentrations associated with balanced phytoplankton
biomass.
In Pensacola Bay, 3 segments in Ochlockonee Bay (Ochlockonee-St.
Marks Offshore/Ochlockonee Offshore/Ochlockonee Bay, segments 0825,
0829, and 0830), and 4 segments in Big Bend/Apalachee Bay (Econfina/
Econfina Offshore, segments 0824, 0832; Steinhatchee-Fenholloway
Offshore, segment 0821; Steinhatchee Offshore, segment 0818), and 1
segment in Springs Coast (Anclote Offshore South, segment 0803), water
clarity was found to be insensitive to changes in nutrients. In
Alligator Harbor and 2 segments in Springs Coast (Waccasassa River
Offshore/Cedar Keys, segments 0814, 0815), there was not enough
available information to derive seagrass depth targets. As a result,
the proposed criteria were derived to be protective of water quality
targets for chlorophyll a concentrations associated with balanced
phytoplankton biomass and dissolved oxygen concentrations sufficient to
maintain aquatic life.
In 2 segments in Ochlockonee Bay (St. Marks Offshore/St. Marks
River, segments 0827, 0828), 2 segments in Big Bend/Apalachee Bay
(Steinhatchee River/Steinhatchee Offshore, segments 0819, 0820), and 2
segments in Springs Coast (Pithlachascotee River/Pithlachascotee
Offshore, segments 0806, 0807), dissolved oxygen and water clarity were
both found to be insensitive to changes in nutrients. In 2 segments in
Big Bend/Apalachee Bay (Fenholloway/Fenholloway Offshore, segments
0822, 0823) and 7 segments in Springs Coast (Crystal River/Crystal-
Homosassa Offshore/Homosassa River, segments 0812, 0813, 0833;
Chassahowitzka River/Chassahowitzka Offshore, segments 0810, 0811; and
Weeki Wachee/Weeki Wachee Offshore, segments 0808, 0809), dissolved
oxygen was found to be insensitive to changes in nutrients and there
was not enough available information to derive seagrass depth targets.
In Nassau River and St. Marys River, dissolved oxygen was found to be
insensitive to changes in nutrients and seagrass has not been
historically present. For all of these estuaries, proposed criteria
were derived that were protective of chlorophyll a concentrations
associated with balanced phytoplankton biomass.
In the Lower St. Johns River, seagrass has not been historically
present, so proposed criteria were derived that were protective of
chlorophyll a associated with balanced phytoplankton biomass and
dissolved oxygen concentrations sufficient to maintain aquatic life.
For this system, EPA used the dissolved oxygen from the Site-Specific
Alternative Criteria, developed by FDEP and adopted for the marine
portion of the Lower St. Johns River, as an additional DO endpoint with
which to derive the proposed criteria to support dissolved oxygen
concentrations sufficient to maintain aquatic life.\195\ This DO
criterion, adopted as a water quality standard specific to this system,
was used as an alternative target to the daily water column average DO
concentration of 5.0 mg/L.
---------------------------------------------------------------------------

\195\ FDEP. 2006. Site Specific Alternative Dissolved Oxygen
Criterion to Protect Aquatic Life in the Marine Portions of the
Lower St. Johns River Technical Support Document. Appendix L In:
FDEP. 2008. TMDL Report: Total Maximum Daily Load for Nutrients for
the Lower St. Johns River. Florida Department of Environmental
Protection, Tallahassee, FL.
---------------------------------------------------------------------------

EPA considered several alternative approaches for deriving
estuarine numeric nutrient criteria, including approaches proposed by
the St. Johns River Water Management District for estuaries within
their jurisdiction (Lower St. Johns River, Mosquito Lagoon, Tolomato-
Matanzas estuary, Halifax River estuary, Indian River Lagoon, and
Banana River). While some of these approaches segmented Florida's
estuaries differently than the segmentation approach EPA is proposing,
all the alternative approaches used multiple biological endpoints and
analytical methods to determine the health of each system and derive
criteria. EPA solicits comments on the alternative approaches described
in more detail in the following sections. Additional details on these
approaches are provided in the TSD (Volume 1: Estuaries, Section 2).
(2) Alternative for St. Johns River Water Management District Waters
The St. Johns River Water Management District (SJRWMD) submitted
proposed approaches to EPA for several estuaries within their
jurisdiction. These included the St. Johns River, Mosquito Lagoon,
Tolomato-Matanzas estuary, Halifax River estuary, Indian River Lagoon,
and Banana River. In general, SJRWMD proposed a weight of evidence
approach employing several analytical techniques to derive numeric
nutrient criteria for each of the systems. The following paragraphs
outline the methods proposed for each of these systems.
The SJRWMD has proposed the use of the values for TN, TP, and
chlorophyll a for the Lower St. Johns River (LSJR) that have already
been developed as part of an existing TMDL to support designated uses
in the river. The LSJR is defined as the main stem segments of the
river between the juncture with the Ocklawaha River and the river mouth
at Mayport, with the marine portion occurring between Julington Creek
and the mouth. A SSAC was developed for DO in the marine portion of the
river. It was approved by EPA in 2006 and is in effect as a WQS. The
TMDL contains TN and TP protective loads in the freshwater portion of
the LSJR and a TN protective load in the saline portion of the LSJR.
These loads are set at a level necessary to achieve the marine DO SSAC
and protect the statewide standard for DO in the freshwater section.
The TMDL also contains a water quality target for chlorophyll a that is
intended to implement the State's narrative nutrient criterion.
Similar to the modeling approach proposed by EPA for Florida
estuaries, TN, TP, and chlorophyll a criteria were derived for the LSJR
using linked watershed, hydrodynamic, and water

[[Page 74954]]

quality models. Non-point nutrient inputs from the watershed to the
river were determined for each sub-basin in the LSJR using the
Pollutant Load Screening Model (PLSM), estimates of atmospheric
deposition, and estimates of loading from tributaries and upstream.
Within the river, hydrodynamics were modeled using the Environmental
Fluid Dynamics Code (EFDC) model and water quality processes were
modeled using the U.S. Army Corps of Engineers Quality Integrated
Compartment Model (CE-QUAL-ICM), Version 2. The models were calibrated
for the period from January 1, 1995 to November 30, 1998. TMDL model
scenarios were assessed on an annual basis to determine if chlorophyll
a levels exceeded the chlorophyll a threshold of 40 [mu]g/L less than
10% of the time that was set as the water quality target to prevent
undesirable shifts in algal community composition.
For Mosquito Lagoon, a suite of five approaches are considered to
develop a weight of evidence by which numeric nutrient criteria can be
developed. These approaches are based upon one of three relationships:
(1) The link between nutrients, phytoplankton growth (as shown by
chlorophyll a), and the trophic state of a system; (2) the link between
nutrients, phytoplankton growth (as shown by chlorophyll a), the
effects of phytoplankton on light attenuation in the water column, and
the light requirements of seagrasses; or (3) the connection between TP
and harmful algal bloom (HAB) occurrence. The first and primary
approach uses a reference period from 2004-2008 to calculate annual
median and maximum wet season medians of chlorophyll a, TN, and TP. The
reference time period was selected because the TN, TP, and chlorophyll
a observed during that period were low, the rainfall amounts during
that period were representative of typical rainfall over time, and the
Trophic State Index value for that time period was greater than 50,
which is considered to be ``good'' (mesotrophy to oligo-mesotrophy).
The second approach draws upon an optical model linking chlorophyll
a to previously established light attenuation targets as a way to
predict annual median chlorophyll a in southern Mosquito Lagoon that
would be protective of seagrass and serve as a basis for criteria
derivation. A third approach derives a TP level that corresponds to
minimum ``bloom'' levels of the dinoflagellate Pyrodinium bahamense,
the common HAB species seen primarily in the southern Lagoon. A fourth
line of evidence applied to the Mosquito Lagoon is multivariate
geometric mean function regression models relating TN and TP to
chlorophyll a on an annual basis and during the wet season. The final
method is based on two general nutrient models.\196\ Targets for
chlorophyll a are set based on the reference period mentioned earlier
for the north and central segments and the optical model for the
southern segments. The reference method is used to derive the TN, TP,
and chlorophyll a criteria for the Mosquito Lagoon with the other four
methods providing supporting evidence. Two criteria magnitudes for TN,
TP, and chlorophyll a are presented; one an annual median value and the
other a wet season (July-September) median value.
---------------------------------------------------------------------------

\196\ Steward, J.S., and E.F. Lowe. 2010. General empirical
models for estimating nutrient load limits for Florida's estuaries
and inland waters. Limnology and Oceanography 55(1):433-445.
Dettmann, E.H. 2001. Effect of water residence time on annual export
and denitrification of nitrogen in estuaries: A model analysis.
Estuaries 24(4):481-490.
---------------------------------------------------------------------------

The approaches used for the Indian River Lagoon (IRL) and Banana
River Lagoon (BRL) are similar to those used for Mosquito Lagoon. The
approaches are based upon a weight of evidence relying on two general
ecological relationships: (1) The link between nutrients, phytoplankton
growth (as shown by chlorophyll a), and the trophic state of a system;
and (2) the link between nutrients, phytoplankton growth (as shown by
chlorophyll a), the effects of phytoplankton on light attenuation in
the water column, the light requirements of seagrasses, and the
previously established depth limit for seagrasses. The influence of TP
on HAB events is also discussed as an ancillary line of evidence. As a
first line of evidence loading limits are derived based on analyses
done for TMDLs in 2009. The loading limits were established using
regression models that regress seagrass depth limit targets against
loading of TN and TP.\197\ The second method used annual medians of
data from reference segments that meet desired depth thresholds
established by the TMDL analyses. The third approach relies upon an
optical model similar to the one described earlier for the Mosquito
Lagoon using data from 1996-2007. A model was built for each of the
sub-lagoons: The BRL, North IRL, and Central IRL (divided into
Sebastian and South Central reaches). An optical model is in
development for the North Central reach. The fourth approach also
applies two general models to data specific to the IRL and BRL.\198\
Where the Dettmann (2001) model could not be used to predict TN
concentrations, a TN:TP ratio for the given sublagoon was applied to
the TP limit to calculate TN limits. The fifth approach relies upon the
relationship between HAB occurrence and TP concentrations. Targets for
chlorophyll a are presented as a range of values established using the
optical model approach and the reference segment approach. Proposed TN
and TP loading criteria are based on the loading limits established
using the TMDL analyses. Primary proposed TN and TP criteria
concentrations are calculated based on the reference segment method.
Alternate criteria are proposed using a convergence of the
concentrations calculated by the reference segment method and general
models. Two criteria magnitudes are proposed, one for an annual median
and the other for a wet season (June-October) monthly maximum.
---------------------------------------------------------------------------

\197\ Steward J.S., R.V. Virnstein, L.J. Morris, and E.F. Lowe.
2005. Setting Seagrass Depth, Coverage, and Light targets for the
Indian River Lagoon system, Florida. Estuaries 6:923-935.
\198\ Steward, J.S., and E.F. Lowe. 2010. General empirical
models for estimating nutrient load limits for Florida's estuaries
and inland waters. Limnology and Oceanography 55(1):433-445.
Dettmann, E.H. 2001. Effect of water residence time on annual export
and denitrification of nitrogen in estuaries: A model analysis.
Estuaries 24:481-490.
---------------------------------------------------------------------------

The SJRWMD proposed criteria for the Tolomato and Matanzas Estuary
(TME) using a weight of evidence approach and methods similar to those
used in the other estuaries. TN and TP concentrations and chlorophyll a
target concentrations are based on an approach that analyzes water
quality and estimated current loading during a reference period from
2000-2009. The period of reference was selected based on a desirable
TSI score (<50), rainfall amounts typical of average conditions, and
completeness of the data record. Criteria magnitudes are proposed as an
annual median or mean and a maximum wet season (June-September) median
or mean. The reference period approach of criteria derivation for the
TME is supported by an additional line of evidence using regression
analyses of chlorophyll a versus TN and TP. Target chlorophyll a values
are based on the reference period analyses. The general nutrient models
of Steward and Lowe (2010) and Dettmann (2001) are also used as an
additional method by which to estimate loading limits and
concentrations associated with those limits.
The SJRWMD also derived proposed criteria for the Halifax River
Estuary. SJRWMD derived criteria using three methods. The first is a
reference condition based on the period from 2000-2008. This period is
selected because of the low TN levels compared

[[Page 74955]]

to the previous decade, the low chlorophyll a concentrations which are
consistent with chlorophyll a targets established for other estuaries
throughout the State, and the ``good'' trophic status shown by TSI
values less than 50. Concentrations are calculated using annual median
concentrations and maximum wet-season median concentrations (as the
highest monthly values from July-September) of TN, TP, and chlorophyll
a. Simple linear regressions are used as a second line of evidence to
calculate TN and TP criteria based on chlorophyll a targets established
by the reference period calculations. The general nutrient models of
Steward and Lowe (2010) and Dettmann (2001) are used as a final method
by which to estimate loading limits and concentrations associated with
those limits. Proposed loading and concentration criteria for the North
Halifax River Estuary are based on the loading and concentration
estimates of the general nutrient models, with estimates of loadings
from wastewater treatment facilities in the estuary removed to
represent reference conditions. The current estimated concentrations
(ca. 2004) of TN and TP based on the reference approach are proposed as
criteria for the South Halifax River Estuary. Target chlorophyll a
values for both segments are calculated using the reference period
approach.
EPA is also considering the use of approaches outlined in Steward
et al. (2005) to derive criteria in Indian River Lagoon. In particular
EPA is considering using the depth of colonization within reference
segments as ``upper restoration depths'' and the highest value observed
for a specific segment as a minimum target for that segment. For more
information regarding the derivation of these criteria, please see the
TSD (Volume 1: Estuaries, Sections 2.18.9 (Indian River Lagoon), 2.19.9
(Halifax River), 2.20.9 (GTMP), and 2.21.9 (St Johns River)).
(3) Request for Comment on Proposed and Alternative Approaches
EPA believes that the proposed approach for each estuarine system
is appropriate, scientifically defensible, and results in numeric
nutrient criteria that protect the State's designated uses to ensure
that nutrient concentrations of a body of water support balanced
natural populations of aquatic flora and fauna. EPA requests comment on
this system-specific approach and the resulting numeric nutrient
criteria. EPA also solicits additional available scientific information
that can be used to derive numeric nutrient criteria to provide
protection of fish consumption, recreation, and the propagation and
maintenance of a healthy, well-balanced population of fish and wildlife
and protect Florida's Class II and III estuarine waters from nitrogen
and phosphorus pollution.
In addition, EPA requests comment on the alternative approaches
developed by the St. Johns River Water Management District for waters
under their jurisdiction. Specifically, EPA requests comment on the
scientific defensibility of these approaches, as well as whether
application of these approaches will result in numeric nutrient
criteria that will protect Class II and III estuarine waters in the
State of Florida. EPA also requests comment on promulgating the
alternative criteria in lieu of EPA's proposed criteria.
(b) Proposed Criteria Duration and Frequency (Estuaries)
Aquatic life water quality criteria include magnitude, duration,
and frequency components. For EPA's proposed TN, TP, and chlorophyll a
criteria for estuarine waters, the criterion-magnitude values
(expressed as concentrations) are provided in Table III.B-1, the
criterion-duration (or averaging period) is specified as annual, and
the criterion-frequency is specified as a no-more-than-once-in-three-
years excursion frequency of the annual geometric mean. EPA is
proposing a criteria-duration of one year, in which sampled nutrient
concentrations are summarized as annual geometric means to be
consistent with the data set used to derive these criteria, which
relied on either annual average nutrient concentrations or annual
nutrient loading to the water body. EPA's proposed excursion frequency
of no-more-than-once-every-three-years is intended to minimize negative
effects on designated uses as it will allow water bodies enough time to
recover from occasionally elevated levels of nitrogen and phosphorus
concentrations.\199\ These duration and frequency components of the
criteria are identical to those finalized in EPA's rule for Florida's
lakes and flowing waters (40 CFR section 131.43), which will add
consistency to the implementation of these criteria with those
established in the previous rulemaking for upstream waters. Finally,
the 3-year evaluation period provides a sufficient representation of
average water body characteristics in the majority of cases, because it
balances both short-term and long-term variation, while not imposing
undue monitoring expectations. EPA requests comment on the frequency
and duration components of these criteria and whether the three
components of the criteria (magnitude, duration, and frequency) taken
in combination will ensure protection of the designated uses of these
waters.
---------------------------------------------------------------------------

\199\ Boynton, W.R., J.D. Hagy, L. Murray, C. Stokes, and W.M.
Kemp. 1996. A comparative analysis of eutrophication patterns in a
temperate coastal lagoon. Estuaries 19(2B):408-421.
---------------------------------------------------------------------------

(c) Proposed DPVs (Estuaries)
EPA is proposing a procedure to establish numeric TN and TP
criteria for streams in Florida to protect the downstream estuarine
water bodies that ultimately receive nitrogen and phosphorus pollution
from these streams. These numeric nutrient criteria, which EPA refers
to as Downstream Protection Values, or DPVs, would apply at each
stream's point of entry into the downstream water, referred to as the
pour point. However, as explained more fully in Section I.A, EPA does
not intend to finalize these DPVs if the district court modifies the
Consent Decree consistent with EPA's amended determination that numeric
DPVs are not necessary to meet CWA requirements in Florida. EPA
selected the pour point as the location to apply DPVs because the
downstream waters respond to the nutrient inputs from the pour point,
and all contributions from the network of flowing waters above this
point affect the water quality at the pour point. If the DPV is not
attained at the point of entry into the estuary, then the collective
set of streams in the upstream watershed does not attain the DPV, for
purposes of CWA section 303(d).
The Agency is proposing a hierarchical procedure that includes four
approaches for setting TN and TP DPVs. EPA's intention in proposing the
four approaches is to provide a range of methods for the State to
derive TN and TP DPVs that reflect the data and scientific information
available. Water quality modeling is the most rigorous and most data-
demanding method, and will generally result in the most refined DPVs.
Water quality modeling is EPA's preferred method for establishing DPVs
and is listed first in the hierarchy. It is followed by less rigorous
methods that are also less data-demanding. Using a procedure from a
lower tier of the hierarchy requires less data, but also generally
results in more stringent DPVs to account for the uncertainties
associated with these less refined procedures. The methods available to
derive DPVs should be considered in the following order:
1. Water quality simulation models to derive TN and TP values,

[[Page 74956]]

2. Reference condition approach based on TN and TP concentrations
at the stream pour point, coincident in time with the data record from
which the downstream receiving estuary segment TN and TP criteria were
developed using the same data quality screens and reference condition
approach,
3. Dilution models based on the relationship between salinity and
nutrient concentration in the receiving segment, and
4. The TN and TP criteria from the receiving estuary segment to
which the freshwater stream discharges, in cases where data are too
limited to apply the first three approaches.
All four approaches are briefly described in the following
discussion. A more detailed description of the approaches, as well as
the TN and TP DPVs that result from using each of the approaches, is
provided in the technical support document (Volume 1: Estuaries,
Section 1.6).
EPA believes that the first approach, the use of water quality
simulation models, is the most refined method to define a DPV at the
stream's pour point that will support balanced natural populations of
aquatic flora and fauna in the downstream estuary. This approach may be
appropriate when water quality simulation models are available, such as
in the estuarine systems where mechanistic models were used to derive
criteria. The modeled nutrient loads entering the estuaries that result
in attainment of the biological endpoints within the estuaries can be
used to derive DPVs by computing the annual geometric mean TN and TP
concentrations that correspond with the modeled loads at the pour point
of each stream for each of the years 2002 through 2009. Because EPA
used coupled watershed and estuarine models to establish the estuary
criteria (in some locations), EPA is confident that the watershed
modeling provides concentrations that are protective of corresponding
estuarine biological endpoints. Therefore EPA selected the 90th
percentile from the distribution of annual geometric means of modeled
loads as the DPV to be consistent with the use of the 90th percentile
used to derive the criteria protective of the estuary using the
mechanistic models (Volume 1: Estuaries, Section 1.6).
EPA is proposing the second DPV approach, a reference condition
approach, for estuarine systems where water quality simulation models
are not available, and where a reference condition approach is used to
derive estuary TN, TP, and chlorophyll a criteria. Since the downstream
estuary is supporting balanced natural populations of aquatic flora and
fauna during the reference condition period, the nutrient loads passing
through the pour points into the estuary during that same period should
be protective of the estuary. Therefore, EPA believes it would be
appropriate in these cases to derive reference condition-based DPVs
using water quality data at the pour point of the freshwater streams,
coincident in time with the data record from which EPA derived the
downstream estuary segment TN and TP criteria. EPA proposes that the
same data screens and reference condition approach be applied to the
pour point data as were applied to the estuary data when deriving DPVs
using this approach. This will prevent deriving a DPV using upstream
water quality data that coincided with a documented downstream impact
(e.g., CWA section 303(d) listing for nutrients in the estuary segment)
and ensure mathematical consistency between the DPVs and estuarine
criteria.
EPA is proposing the third DPV approach for estuarine systems where
water quality simulation models are not available. For example, this
approach may be appropriate in the Indian River Lagoon, the Halifax
River, and the GTMP estuarine systems where EPA used statistical models
to derive the criteria protective of the estuary. In these areas, EPA
believes it would be appropriate to derive DPVs using dilution models
based on the relationship between salinity and nutrient concentration.
The concept is that the tidal mixing or dilution can be estimated from
the estuarine salinity. By plotting observed estuarine TN or TP versus
the estuarine salinity and fitting a linear regression, the TN or TP at
various levels of salinity can be determined. This regression model can
then be used to determine the TN or TP concentration at the pour point
that will ensure attainment and maintenance of the estuarine numeric
nutrient criteria concentration. The TN and TP DPV for the inflowing
canal or stream can be determined from the point on the regression line
having the same salinity as the pour point, which is by definition 2.7
psu.
EPA's fourth proposed approach for establishing DPVs is to apply
the downstream receiving estuary segment TN and TP criteria as shown in
Table III.B-1 to the pour point as the DPVs. This is the simplest
approach and may be appropriate where data are too limited to apply the
first three approaches. As noted in Table III.B-1, Florida derived
numeric nutrient criteria for Clearwater Harbor, Tampa Bay, Sarasota
Bay, and Charlotte Harbor estuaries that can be found in Section 62-
302.532(a)-(d), F.A.C. Therefore, the applicable DPVs for those four
estuaries would be Florida's estuary criteria in Section 62-302.532(a)-
(d), F.A.C. if using this fourth proposed approach for establishing
DPVs.
EPA believes the proposed approaches for deriving DPVs establish a
decision-making framework that is binding, clear, predictable, and
transparent. Therefore, EPA is proposing that DPVs derived using these
approaches do not require EPA approval under Clean Water Act section
303(c) to take effect.\200\ A DPV calculated under options 2, 3, and 4
may be more stringent than a DPV calculated using a water quality
model. These alternative options are intended to ensure that water
quality standards are not only restored when found to be impaired, but
are maintained when found to be attained, consistent with the CWA.
Higher levels of TN and/or TP may be allowed in watersheds where it is
demonstrated that such higher levels will fully protect the estuary's
WQS. To the extent that it is determined that the alternative option
DPVs for a given estuary are over-protective, applying a water quality
model as set out in EPA's option 1 would result in a more refined
definition of the DPV for that estuary.
---------------------------------------------------------------------------

\200\ 65 FR 24641, 24648 (April 27, 2000).
---------------------------------------------------------------------------

EPA believes that these proposed approaches to establish DPVs are
appropriate, scientifically defensible, and result in numeric values
that will ensure the attainment and maintenance of the downstream
estuarine criteria. EPA requests comment on these approaches. EPA also
requests comment on the alternative approach of finalizing the numeric
TN and TP DPVs that EPA calculated using these approaches (as provided
in Volume 1: Estuaries, Section 1.6 of the technical support document)
in place of the proposed approaches. Finally, EPA solicits additional
available scientific information that can be used to ensure attainment
and maintenance of the downstream estuarine criteria. Commenters who
submitted comments or scientific information related to DPVs for
estuaries during the public comment period for EPA's proposed inland
waters rule (75 FR 4173) should reconsider their previous comments in
light of the new information presented in this proposal and must re-
submit their comments during the public comment period for this
rulemaking to receive EPA response.

[[Page 74957]]

(d) Proposed Approach and Criteria for Tidal Creeks
Tidal creeks are relatively small coastal tributaries that lie at
the transition zone between terrestrial uplands and the open estuary.
They are small sub-estuaries that exhibit a wide range of salinities
typical of larger estuaries, but on a smaller scale. Tidal creeks are
important spawning and nursery areas for aquatic life in adjacent
estuary and coastal systems. They typically receive freshwater flow
from streams and groundwater, similar to estuaries, but have less
developed drainage systems. Alternatively, some tidal creeks are
dominated by mangroves and other wetland vegetation with no freshwater
stream inputs, and serve as conduits for tidal water to enter and leave
wetland areas. Water quality and biological conditions are different in
tidal creeks compared to estuarine systems due to relatively small
drainage areas, narrow stream channels, shallow depths, and the
influence of adjacent marsh and mangrove habitats.
EPA reviewed the available scientific information and has
determined that there are insufficient data and research at this time
to develop separate numeric nutrient criteria specifically for tidal
creeks. EPA, therefore, proposes to apply the TN and TP criteria
developed for either the adjacent freshwater or estuarine segments to
each tidal creek in Florida, depending on the tidal creek's salinity
levels. If the mean chloride concentration of the tidal creek is <
1,500 mg/L, EPA proposes to apply the TN and TP criteria from the
adjacent freshwater segment (as defined in 40 CFR 131.43).\201\ If the
mean chloride concentration of the tidal creek is > 1,500 mg/L, EPA
proposes to apply the chlorophyll a, TN, and TP criteria from the
adjacent estuary segment (as defined in Section III.B of this proposed
rulemaking). Alternatively, EPA requests comment on applying the more
stringent of the two sets of criteria, freshwater or estuarine, to
tidal creeks with varying salinity levels. For more information please
see the TSD (Volume 1: Estuaries, Section 3.1).
---------------------------------------------------------------------------

\201\ EPA did not establish chlorophyll a criteria for
freshwater streams due to lack of available approaches to interpret
existing data to infer scientifically supported thresholds for these
nutrient-specific response variables in Florida streams.
---------------------------------------------------------------------------

As a second alternative option, EPA could use the mean salinities
for each tidal creek to interpolate TN and TP concentrations between
freshwater and estuarine criteria from adjacent freshwater and
estuarine segments. TN and TP vary predictably along a salinity
gradient, allowing for this interpolation where salinity data are
available. The calculation EPA could use for this interpolation is
provided in the TSD (Volume 1: Estuaries, Section 3.1).
EPA believes that the proposed approach for tidal creeks is
appropriate, scientifically defensible, and results in numeric nutrient
criteria that protect the State's designated uses and ensure that
nutrient concentrations of a body of water support balanced natural
populations of aquatic flora and fauna. EPA requests comment on the
proposed option and the alternative. EPA also requests additional
available scientific information that can be used to provide protection
for fish consumption, recreation, and the propagation and maintenance
of a healthy, well-balanced population of fish and wildlife to protect
Florida's tidal creeks from nitrogen and phosphorus pollution.
(e) Proposed Approach and Criteria for Marine Lakes
Marine lakes are coastal lakes and ponds with groundwater or
intermittent surface water connections to marine water. They do not
have a permanent surface connection to tidal waters. They are small and
shallow, and generally round or elliptical in shape, as they were
formed from depressions that became isolated from marine waters by sand
and dune formation. Some marine lakes are stratified by a salinity
gradient where a freshwater layer at the surface is separated from a
denser saline layer below. Similar to inland lakes, marine lakes in
Florida are generally oligotrophic under undisturbed conditions with
low nitrogen and phosphorus concentrations and low productivity. Their
oligotrophic nature and stratification make them susceptible to the
adverse effects of nitrogen and phosphorus pollution. EPA analyzed the
data from over 50 marine lakes in Florida and found that chlorophyll a
responded to TN and TP in a similar fashion, based on color and
alkalinity, as freshwater inland lakes. Details and supporting
documentation are provided in the TSD (Volume 1: Estuaries, Section
3.2).
EPA is proposing to apply the criteria developed for freshwater
inland lakes in EPA's December 6, 2010 rulemaking for Florida's lakes
and flowing waters (40 CFR 131.43) to protect the designated uses in
marine lakes since marine lakes have a similar trophic condition
expectation and chlorophyll a response to nutrient concentrations. The
criteria EPA proposes to apply to marine lakes are those found in 40
CFR 131.43 and replicated in Table III.B-2.

Table III.B-2--EPA's Proposed Numeric Criteria for Florida's Marine Lakes
----------------------------------------------------------------------------------------------------------------
EPA final EPA final TN and TP criteria [Range]
Long term average lake color \a\ and alkalinity Chl[dash]a ---------------------------------------
\b,*\[micro]g/L TN mg/L TP mg/L
----------------------------------------------------------------------------------------------------------------
Colored lakes \c\................................... 20 1.27 [1.27-2.23] 0.05 [0.05-0.16]
Clear lakes, high alkalinity \d\.................... 20 1.05 [1.05-1.91] 0.03 [0.03-0.09]
Clear lakes, low alkalinity \e\..................... 6 0.51 [0.51-0.93] 0.01 [0.01-0.03]
----------------------------------------------------------------------------------------------------------------
\a\ Platinum-cobalt units (PCU) assessed as true color free from turbidity.
\b\ Chl-a is defined as corrected chlorophyll, or the concentration of chl-a remaining after the chlorophyll
degradation product, phaeophytin a, has been subtracted from the uncorrected chl-a measurement.
\c\ Long-term color > 40 PCU and alkalinity > 20 mg/L CaCO3.
\d\ Long-term color <= 40 PCU and alkalinity > 20 mg/L CaCO3.
\e\ Long-term color <= 40 PCU and alkalinity <= 20 mg/L CaCO3
* For a water body, the annual geometric mean of chl-a, TN or TP concentrations shall not exceed the applicable
criterion concentration more than once in a three-year period.

[[Page 74958]]

EPA believes that the proposed approach for marine lakes is
appropriate, scientifically defensible, and results in numeric nutrient
criteria that protect the State's designated uses and ensure that
nutrient concentrations of a body of water support balanced natural
populations of aquatic flora and fauna. EPA requests comment on the
proposed approach. EPA also solicits additional available scientific
information that can be used to provide protection for fish
consumption, recreation, and the propagation and maintenance of a
healthy, well-balanced population of fish and wildlife to protect
Florida's marine lakes from nitrogen and phosphorus pollution.

C. Proposed Numeric Criteria for Coastal Waters

1. Introduction
EPA is defining coastal waters in this proposed rulemaking as
marine waters that start at the land margin and extend up to three
nautical miles from shore, with chloride concentrations greater than
1,500 mg/L, excluding estuaries. Unlike estuaries, which are typically
highly influenced by freshwater flows and can be organized within
boundaries, coastal waters are less confined, with open connections to
ocean waters, and have localized influences from freshwater sources
near the estuary/coastal boundary (i.e., estuary pass).
EPA is proposing to derive chlorophyll a criteria for coastal
waters using satellite remote sensing, where possible. This approach is
possible for all coastal waters except those in the Big Bend Coastal
region. In the Big Bend Coastal region (waters offshore of Apalachicola
Bay, Alligator Harbor, Ochlockonee Bay, Big Bend/Apalachee Bay,
Suwannee River, and Springs Coast), seagrass beds and CDOM export from
rivers confound interpretation of satellite data and derivation of
chlRS-a. EPA's proposed approach and criteria for the Big
Bend Coastal region is discussed in Section III.B.
2. Proposed Numeric Criteria (Coastal Waters)
EPA is proposing numeric chlorophyll a criteria, as measured by
remotely sensed numeric chlorophyll a (chlRS-a), for 71
segments in three coastal regions of Florida classified as Class III
waters under Florida law (Section 62-302.400, F.A.C.). A map showing
the locations of the coastal segments can be found in the TSD (Volume
2: Coastal Waters, Section 1.3). EPA's proposed coastal criteria are
listed in Table III.C-1.

Table III.C-1--EPA's Proposed Numeric Criteria for Florida's Coastal Waters
----------------------------------------------------------------------------------------------------------------
Coastal ChlorophyllRS -
Coastal region segment\+\ Approximate location a\1\* (mg/m\3\)
----------------------------------------------------------------------------------------------------------------
Panhandle.................................. 1 Alabama border............... 2.41
2 Pensacola Bay Pass........... 2.57
3 ............................. 1.44
4 ............................. 1.16
5 ............................. 1.06
6 ............................. 1.04
7 ............................. 1.14
8 Choctawhatchee Bay Pass...... 1.23
9 ............................. 1.08
10 ............................. 1.09
11 ............................. 1.11
12 ............................. 1.18
13 ............................. 1.45
14 St. Andrews Bay Pass......... 1.74
15 St. Joseph Bay Pass.......... 2.75
16 ............................. 2.39
17 Southeast St. Joseph Bay..... 3.47
West Florida Shelf......................... 18 ............................. 3.96
19 Tampa Bay Pass............... 4.45
20 ............................. 3.37
21 ............................. 3.25
22 ............................. 2.95
23 ............................. 2.79
24 ............................. 2.98
25 ............................. 3.24
26 Charlotte Harbor............. 4.55
27 ............................. 4.22
28 ............................. 3.67
29 ............................. 4.16
30 ............................. 5.70
31 ............................. 4.54
32 ............................. 4.03
33 Fort Myers................... 4.61
Atlantic Coast............................. 34 Biscayne Bay................. 0.92
35 ............................. 0.26
36 ............................. 0.26
37 ............................. 0.24
38 ............................. 0.21
39 ............................. 0.21
40 ............................. 0.20
41 ............................. 0.20
42 ............................. 0.21
43 ............................. 0.25
44 ............................. 0.57

[[Page 74959]]

45 St. Lucie Inlet.............. 1.08
46 ............................. 1.42
47 ............................. 1.77
48 ............................. 1.55
49 ............................. 1.44
50 ............................. 1.53
51 ............................. 1.31
52 ............................. 1.40
53 ............................. 1.80
54 Canaveral Bight.............. 2.73
55 ............................. 2.33
56 ............................. 2.28
57 ............................. 2.06
58 ............................. 1.92
59 ............................. 1.76
60 ............................. 1.72
61 ............................. 2.04
62 ............................. 1.92
63 ............................. 1.86
64 ............................. 1.95
65 ............................. 2.41
66 ............................. 2.76
67 ............................. 2.80
68 ............................. 3.45
69 Nassau Sound................. 3.69
70 ............................. 3.78
71 Georgia border............... 4.22
----------------------------------------------------------------------------------------------------------------
\1\ ChlorophyllRS-a is remotely sensed calculation of chlorophyll a concentrations.
* For a given water body, the annual geometric mean of the chlorophyll a concentration shall not exceed the
applicable criterion concentration more than once in a three-year period.
\+\ Please see TSD for location of Coastal Segments (Volume 2: Coastal Waters, Section 1.3).

As discussed in Section III.A.1.b, EPA is not proposing TN and TP
criteria for Florida's coastal waters.
(a) Summary of Approaches
(1) Proposed Approach (Coastal Waters)
EPA conducted a comprehensive review of water body-specific water
quality and impairment information as detailed in Section III.A.3.a.
EPA determined through this review that at most times, Florida coastal
waters appear to be supporting balanced natural populations of aquatic
flora and fauna. EPA removed data from criteria computations in the
limited instances where the Agency found that coastal waters were
listed on the State's CWA section 303(d) list to ensure the resulting
dataset was representative of times and locations that these waters
were supporting balanced natural populations of aquatic flora and
fauna. Therefore, EPA is proposing to use a reference condition
approach using data collected from satellite remote sensing of
chlorophyll a.
To derive proposed criteria for coastal areas, EPA chose to use
chlRS-a measurements from the SeaWiFS satellite because it
had the longest and earliest historical record.\202\ From the satellite
measurements, screened to reflect conditions supportive of balanced
natural populations of flora and fauna, EPA calculated criteria as the
90th percentile of the annual geometric means of chlRS-a
values over the 1998-2009 period in each coastal segment (For a
discussion of EPA's selection of the 90th percentile to derive the
proposed coastal criteria, see Section III.A.3.a and the TSD (Volume 2:
Coastal Waters)).
---------------------------------------------------------------------------

\202\ NOTE: SeaWiFS was replaced by MODIS and MERIS satellite
generated data. EPA has developed an approach that can utilize any
new satellite data sources for ongoing assessment purposes.
---------------------------------------------------------------------------

(b) Request for Comment on Proposed Approach
EPA believes that the proposed approach for coastal waters is
appropriate, scientifically defensible, and results in numeric nutrient
criteria that protect the State's designated uses and ensure that
nutrient concentrations of a body of water support balanced natural
populations of aquatic flora and fauna. EPA requests comment on this
approach and the resulting numeric nutrient criteria. EPA also solicits
additional available scientific information that can be used to provide
protection of fish consumption, recreation and the propagation and
maintenance of a healthy, well-balanced population of fish and wildlife
and protect Florida's Class III coastal waters from nitrogen and
phosphorus pollution.
(c) Proposed Criteria Duration and Frequency (Coastal Waters)
For EPA's proposed chlorophyll a criteria for coastal waters, the
criterion-magnitude values (expressed as concentrations) are provided
in Table III.C-1, the criterion-duration (or averaging period) is
specified as annual, and the criterion-frequency is specified as no-
more-than-once-every-three-years. EPA is proposing a criteria-duration
of one year, in which sampled chlorophyll a concentrations are
summarized as annual geometric means, to be consistent with the data
set used to derive these criteria, which relied on annual average
concentrations. EPA's proposed excursion frequency of no-more-than-
once-every-three-years is intended to minimize negative effects on
designated uses as it will allow water bodies enough time to recover
from occasionally elevated chlorophyll a

[[Page 74960]]

concentrations.\203\ These duration and frequency components of the
criteria are identical to those finalized in EPA's rule for Florida's
lakes and flowing waters (40 CFR 131.43), which will add consistency to
the implementation of these criteria with those established in the
previous rulemaking. Finally, the 3-year evaluation period provides a
sufficient representation of average water body characteristics in the
majority of cases, because it balances both short-term and long-term
variation, while not imposing undue monitoring expectations. EPA
requests comment on the frequency and duration components of these
criteria and whether the three components of the criteria (magnitude,
duration and frequency) taken in combination will ensure protection of
the designated uses of these waters.
---------------------------------------------------------------------------

\203\ Boynton, W.R., J.D. Hagy, L. Murray, C. Stokes, and W.M.
Kemp. 1996. A comparative analysis of eutrophication patterns in a
temperate coastal lagoon. Estuaries 19(2B):408- 421.
---------------------------------------------------------------------------

D. Proposed Numeric Criteria for South Florida Inland Flowing Waters

1. Proposed Numeric Criteria (South Florida Inland Flowing Waters)
For purposes of this proposal, EPA is defining ``south Florida
inland flowing waters'' as inland predominantly fresh surface waters
that have been classified as Class I or Class III in the South Florida
Nutrient Watershed Region, which encompasses the waters south of Lake
Okeechobee, the Caloosahatchee River (including Estero Bay) watershed,
and the St. Lucie watershed. This area contains more than 1,700 miles
(2,736 km) of canals, dikes, and levees that control the movement of
freshwater in south Florida. Some of the significant land management
units within south Florida include the Everglades Agricultural Area,
the Loxahatchee National Wildlife Refuge (Water Conservation Area 1),
Water Conservation Areas 2 and 3, Big Cypress National Preserve,
Everglades National Park, Biscayne Bay National Park, and the Florida
Keys National Marine Sanctuary. A map showing this region is provided
in the TSD (Volume 3: South Florida Inland Flowing Waters, Section 3).
EPA is proposing that TN and TP DPVs be derived using the
approaches outlined in Section III.D.2 for 22 pour points in south
Florida, outside of the Everglades Protection Area (EvPA) and
Everglades Agricultural Area (EAA), where inland flowing waters
discharge into south Florida marine waters (Biscayne Bay, Florida Bay,
and marine waters on the southeast and southwest coasts). For south
Florida, EPA is proposing the use of DPVs to manage nitrogen and
phosphorus pollution in the inland flowing waters and protect the water
quality of estuaries and coastal waters downstream. Therefore, the
applicable numeric nutrient criteria for south Florida inland flowing
waters, outside the lands of the Miccosukee and Seminole Tribes, EvPA,
and the EAA, would consist solely of the south Florida marine water
DPVs. The calculated DPVs using the approaches in Section III.D.2 for
the 22 pour points are presented in the TSD (Volume 3: South Florida
Inland Flowing Waters, Section 2).
The proposed approaches to derive DPVs that EPA is proposing for
south Florida inland flowing waters do not apply to flowing waters
(canals) within the EvPA or the EAA. There is an existing TP criterion
of 0.010 mg/L (10 ppb) that currently applies to the marshes and
adjacent canals within the EvPA (Section 61-302.540, F.A.C.). EPA
approved that TP criterion in 2005 as protective of the waters in the
EvPA. EPA's approval was upheld by the U.S. District Court in
Miccosukee Tribe of Indians of Florida, et al. v. U.S. EPA.\204\ For
this proposal, EPA has determined that the existing TP criterion
continues to be protective of the designated uses of the flowing waters
in the EvPA and that no additional numeric nutrient criteria are
necessary at this time for the EvPA. While the existing TP criterion
does not apply directly to the flowing waters of the EAA, EPA has also
determined that the TP criterion will serve to be protective of the
designated uses of the flowing waters in the EAA. Most of the water
flowing from the EAA currently passes through stormwater treatment
areas (STAs) that have been specifically constructed to remove
phosphorus from the water before it enters the EvPA. The waters
discharging from the STAs are subject to CWA discharge permits that
must include limits as stringent as necessary to meet the 10 ppb TP
criterion in the EvPA. Efforts to reduce phosphorus upstream of the
STAs (i.e., in the EAA) are currently underway to ensure the water
discharged from the STAs will meet the TP criterion in the EvPA. Based
on the combination of the actions that will be necessary to ensure that
waters from the EAA do not cause an impairment of the downstream waters
in the EvPA, EPA has determined that the existing TP criterion is the
only numeric nutrient criterion that is necessary to protect the
flowing waters of the EAA as well as the EvPA. Development of water
quality standards for the EvPA and restoration actions within the EAA
to attain the TP criterion have been and remain subject to the
oversight of two federal district courts. EPA believes its decision not
to propose additional numeric nutrient criteria for these areas is
appropriate given the ongoing restoration efforts in the Everglades.
For further information about ongoing EPA and FDEP actions related to
Everglades restoration see: (1) http://www.epa.gov/aboutepa/states/fl.html, and (2) http://depnewsroom.wordpress.com/hot-topics/everglades/.
---------------------------------------------------------------------------

\204\ Miccosukee Tribe of Indians of Fla., et al. v. U.S. EPA,
No. 1:04-cv-21448 ASG, 2008 WL 2967654 (S.D. Fla. July 29, 2008).
---------------------------------------------------------------------------

2. Proposed DPVs (South Florida)
EPA is proposing a procedure to establish numeric TN and TP
criteria for south Florida inland flowing waters to protect the
downstream marine waters that ultimately receive nitrogen and
phosphorus pollution from upstream sources. However, as explained more
fully in Section I.A, EPA does not intend to finalize these DPVs if the
district court modifies the Consent Decree consistent with EPA's
amended determination that numeric DPVs are not necessary to meet CWA
requirements in Florida. Like the DPVs that EPA is proposing to protect
estuaries in Florida, EPA is proposing the DPVs for south Florida
inland flowing waters that will apply at each stream or canal's point
of entry into the downstream south Florida marine water. If the DPV is
not attained at the pour point into the applicable marine water
segment, then the collective set of flowing waters, including canals,
in the upstream watershed does not attain the DPV, for purposes of CWA
section 303(d).
The Agency is proposing a hierarchical procedure that includes four
approaches for setting TN and TP DPVs. These are the same approaches
EPA is proposing for the State to derive DPVs for Florida estuaries to
reflect the data and scientific information available. The methods
available to derive DPVs should be considered in the following order:
1. Water quality simulation models to derive TN and TP values,
2. Reference condition approach based on TN and TP concentrations
at the stream pour point, coincident in time with the data record from
which the downstream receiving marine water segment TN and TP criteria
were developed using the same data quality screens and reference
condition approach,
3. Dilution models based on the relationship between salinity and

[[Page 74961]]

nutrient concentration in the receiving segment, and
4. The TN and TP criteria from the receiving marine water segment
to which the freshwater stream discharges, in cases where data are too
limited to apply the first three approaches.
EPA's intention in proposing the four approaches is to provide a
range of methods for deriving TN and TP DPVs that reflect the degree of
data and scientific information available. Water quality modeling is
the most rigorous and most data-demanding method, and will generally
result in the most refined DPVs. Water quality modeling is EPA's
preferred method for establishing DPVs and is listed first in the
hierarchy. Due to the highly modified and managed canal systems in
south Florida, EPA did not develop mechanistic models for the region,
however, EPA is including the option for use if mechanistic models are
developed for south Florida in the future. EPA's lead approach for
calculating DPVs in south Florida is the reference condition approach.
This approach is followed by less rigorous methods that are also less
data-demanding. Using a procedure from a lower tier of the hierarchy
requires less data, but also generally results in more stringent DPVs
to account for the uncertainties associated with these less refined
procedures.
All four approaches are briefly described in the following
discussion. A more detailed description of the approaches, as well as
the TN and TP DPVs that result from using the lead approach, the
reference condition approach, is provided in the technical support
document (Volume 3: South Florida Inland Flowing Waters, Section 2).
EPA believes that the first approach, the use of water quality
simulation models, is the most refined method to define a DPV at the
stream's pour point that will support balanced natural populations of
aquatic flora and fauna in the downstream marine water. This approach
may be appropriate when water quality simulation models are available,
such as in the estuarine systems where mechanistic models were used to
derive the criteria protective of the estuary.
EPA is proposing the second DPV approach, the reference condition
approach, where a reference condition approach is used to derive TN,
TP, and chlorophyll a criteria in the downstream marine water, as the
lead approach for calculating DPVs in south Florida. Florida derived
numeric nutrient criteria for TN, TP, and chlorophyll a in south
Florida marine waters using a ``Maintain Healthy Conditions Approach,''
which derives criteria reflective of ambient water quality conditions
(Section 62-302.532, F.A.C.). This approach is akin to EPA's reference
condition approach, which is designed to develop numeric nutrient
criteria that are protective of applicable designated uses by
identifying numeric nutrient criteria concentrations occurring in
least-disturbed waters that are supporting designated uses. Since the
downstream marine water is supporting balanced natural populations of
aquatic flora and fauna during the reference condition period, the
nutrient loads passing through the pour points into the marine water
during the same period should be protective of the marine water.
Therefore, EPA believes it would be appropriate in these cases to
derive reference condition-based DPVs using water quality data at the
pour point of the freshwater streams, coincident in time with the data
record from which the downstream marine water segment TN and TP
criteria were derived. EPA proposes that water quality data used to
calculate DPVs at each pour point be screened to prevent the use of
upstream water quality data that coincided with a documented downstream
impact. This will prevent deriving a DPV using upstream water quality
data that coincided with a documented downstream impact (e.g., CWA
section 303(d) listing for nutrients in the marine water segment) and
ensure mathematical consistency between the DPVs and marine water
criteria.
The third DPV approach is also available for south Florida marine
systems where water quality simulation models are not available. In
these areas, EPA believes it would be appropriate to derive DPVs using
dilution models based on the relationship between salinity and nutrient
concentration. The concept is that the tidal mixing or dilution can be
estimated from the marine water salinity. By plotting observed marine
water TN or TP versus the marine water salinity and fitting a linear
regression, the TN or TP at various levels of salinity can be
determined. This regression model can then be used to determine the TN
or TP concentration at the pour point associated with the average
marine water salinity that will ensure the attainment and maintenance
of the marine water numeric nutrient criteria concentration.
EPA's fourth approach for establishing DPVs is to apply the
downstream receiving marine water segment TN and TP criteria to the
pour point as the DPVs. This is the simplest approach and may be
appropriate where data are too limited to apply the first three
approaches. Florida derived numeric nutrient criteria for south Florida
marine waters that can be found in Section 62-302.532(e)-(h), F.A.C.
Therefore, the applicable DPVs for those south Florida marine waters
would be Florida's criteria in Section 62-302.532(e)-(h), F.A.C. if
using this fourth proposed approach for establishing DPVs.
EPA believes the proposed approaches for deriving DPVs establish a
decision-making framework that is binding, clear, predictable, and
transparent. Therefore, EPA is proposing that DPVs derived using these
approaches do not require EPA approval under Clean Water Act section
303(c) to take effect.\205\ A DPV calculated under options 2, 3, and 4
may be more stringent than a DPV calculated using a water quality
model. These alternative options are intended to ensure that water
quality standards are not only restored when found to be impaired, but
are maintained when found to be attained, consistent with the CWA.
Higher levels of TN and/or TP may be allowed in watersheds where it is
demonstrated that such higher levels will fully protect the marine
water's WQS. To the extent that it is determined that the alternative
option DPVs for a given marine water are over-protective, applying a
water quality model as set out in EPA's option 1 would result in a more
refined definition of the DPV for that marine water.
---------------------------------------------------------------------------

\205\ 65 FR 24641, 24647 (April 27, 2000).
---------------------------------------------------------------------------

EPA believes that these proposed approaches to establish DPVs are
appropriate, scientifically defensible, and result in numeric values
that will ensure the attainment and maintenance of the downstream south
Florida marine water criteria. EPA requests comment on these
approaches. EPA also requests comment on the alternative approach of
finalizing the numeric TN and TP DPVs that EPA calculated using these
approaches (as provided in Volume 3: South Florida Inland Flowing
Waters, Section 2 of the technical support document) in place of the
proposed approaches. Finally, EPA solicits additional available
scientific information that can be used to ensure attainment and
maintenance of the downstream south Florida marine water criteria.
Commenters who submitted comments or scientific information related to
DPVs for estuaries during the public comment period for EPA's proposed
inland waters rule (75 FR 4173) should reconsider their previous
comments in light of the new information presented in this proposal and
must re-submit their comments

[[Page 74962]]

during the public comment period for this rulemaking to receive EPA
response.
(a) Alternative Approach (South Florida Inland Flowing Waters)
As an alternative to EPA's proposed DPV-only approach for south
Florida inland flowing waters, EPA developed protective instream TN and
TP criteria for Class I and III flowing waters (including canals and
streams) in three inland subregions in south Florida (Biscayne, Palm
Beach, and West) that are outside the lands of the Miccosukee and
Seminole Tribes, EAA, and EvPA. EPA's alternative criteria for south
Florida inland flowing waters are listed in Table III.D-1.

Table III.D-1--EPA's Alternative Numeric Criteria for South Florida's
Inland Flowing Waters
------------------------------------------------------------------------
TN (mg/ TP (mg/
Subregion L) L)
------------------------------------------------------------------------
Biscayne.............................................. 2 0.052
Palm Beach............................................ 2 0.052
West.................................................. 2 0.052
------------------------------------------------------------------------

EPA defined the boundaries of these three subregions based on
patterns in geology/soils, hydrology, and vegetation. EPA compiled data
for these subregions from IWR Run 40 and the South Florida Water
Management District's DBHydro database. EPA screened the data to
include freshwater locations and Class III waters, resulting in 4,758
daily averages with matched chl-a, TN, and TP data.
Next, EPA chose to evaluate algal biomass, as indicated by
chlorophyll a concentrations, as a sensitive endpoint for numeric
nutrient criteria development. Nutrient pollution can increase biomass
of primary producers, especially algae, and have subsequent negative
impacts on recreation and aquatic life. The application of algal
biomass as an endpoint for criteria derivation in south Florida inland
flowing waters, including canals, might be appropriate given the
following observations: (1) Flow in these water bodies is frequently
reduced, leading to long residence times; (2) canopy cover is reduced
both naturally and through manipulation, reducing light limitation; and
(3) nutrient concentrations are elevated. Because both average
chlorophyll a concentrations and instantaneous chlorophyll a
concentrations (e.g. bloom conditions) can impact recreation and
aquatic life, EPA chose to derive TN and TP criteria to reduce the
likelihood of increased nuisance algal blooms by relating maximum
chlorophyll a to average annual chlorophyll concentrations. EPA defined
nuisance algal bloom conditions as concentrations above 30 [micro]g/L
using trophic state boundaries, user perception studies, and observed
impacts. EPA evaluated existing scientific literature on the frequency
of occurrence of chlorophyll a levels, and selected a 10 percent
occurrence of nuisance algal blooms as the maximum allowable frequency
to prevent impairment of recreation and aquatic life in the three south
Florida inland subregions.\206\
---------------------------------------------------------------------------

\206\ Havens, K.E. and W.W. Walker. 2002. Development of a total
phosphorus concentration goal in the TMDL process for Lake
Okeechobee, Florida (USA). Lake and Reservoir Management 18(3):227-
238.
---------------------------------------------------------------------------

EPA then used statistical models to derive TN and TP criteria to
limit the frequency of occurrence of nuisance algal blooms in these
waters, defined by chlorophyll a concentrations above 30 [micro]g/L.
The resulting TN and TP criteria represent the annual geometric mean of
TN and TP concentrations from flowing waters in each of the three
subregions that are associated with a 10 percent or lower frequency of
nuisance algal bloom occurrence. If EPA were to finalize this
alternative approach instead of EPA's lead approach, these TN and TP
criteria would apply throughout the flowing waters in each of the three
subregions, not just at the pour points. If criteria are calculated
using this alternative approach, DPVs for protecting downstream south
Florida marine waters will still be calculated using the hierarchical
approach in Section III.D.2, unless, as described more in Section I.A,
the district court modifies the Consent Decree consistent with EPA's
amended determination that numeric DPVs are not necessary to meet CWA
requirements in Florida. Additional details on this alternative
approach are provided in the TSD (Volume 3: South Florida Inland
Flowing Waters, Section 3).
(b) Request for Comment on Proposed and Alternative Approaches
EPA believes that the proposed approach for south Florida inland
flowing waters is appropriate, scientifically defensible, and results
in the protection of south Florida inland flowing waters. EPA requests
comment on this approach. EPA also solicits additional available
scientific information that can be used to provide protection of fish
consumption, recreation and the propagation and maintenance of a
healthy, well-balanced population of fish and wildlife in south
Florida's Class I and III inland flowing waters from nitrogen and
phosphorus pollution.
In addition, EPA requests comment on the alternative approach of
deriving instream criteria for south Florida inland flowing waters
outside of the lands of the Miccosukee and Seminole Tribes, EvPA, and
EAA. Specifically, EPA requests comment on the scientific defensibility
of this alternative approach as well as whether application of this
approach will result in numeric nutrient criteria that protect the
State's designated uses and ensure that nutrient concentrations of a
body of water support balanced natural populations of aquatic flora and
fauna.
Commenters who submitted comments or scientific information related
to numeric nutrient criteria for south Florida inland flowing waters
during the public comment period for EPA's proposed inland waters rule
(75 FR 4173) should reconsider their previous comments in light of the
new information presented in this proposal and must re-submit their
comments during the public comment period for this rulemaking to
receive EPA response.

F. Applicability of Criteria When Final

EPA proposes that the numeric nutrient criteria for Florida's
estuaries, coastal waters, and south Florida inland flowing waters
described in this rule be effective for CWA purposes 60 days after EPA
publishes final criteria, and apply in addition to any other criteria
for Class I, II, or Class III waters already adopted by the State and
submitted to EPA (and for those adopted after May 30, 2000, approved by
EPA). EPA requests comment on this proposed effective date.
Additionally, EPA also requests comment on the alternative of a
delayed effective date, such as the 15-month delayed effective date
that EPA promulgated in the final inland waters rule. EPA subsequently
further extended the effective date of the 2010 rule to allow time for
FDEP to finalize and EPA to review Florida's own numeric nutrient
criteria rulemaking and reduce any administrative confusion and
inefficiency that should occur if Federal criteria took effect while
FDEP was finalizing or EPA was reviewing the State rulemaking.
Florida's newly-approved State WQS include a schedule for future State
rulemaking whereby they will develop numeric nutrient criteria for
additional estuaries by June 30, 2013 and again by June 30, 2015. If
Florida is on schedule toward adoption of protective and approvable
standards for their additional waters, EPA may consider delaying the
effective date of

[[Page 74963]]

its final rule to after June 30, 2015 to allow time for Florida to
finalize and EPA to review the State's numeric nutrient criteria.
For water bodies that Florida has designated as Class I, II, and
III, any final EPA numeric nutrient criteria will be applicable CWA
water quality criteria for purposes of implementing CWA programs
including permitting under the NPDES program, as well as monitoring and
assessment, and establishment of TMDLs. The proposed criteria in this
rule, when finalized, would be subject to Florida's general rules of
applicability to the same extent as are other State-adopted and/or
federally-promulgated criteria for Florida waters. Furthermore, states
have discretion to adopt general policies that affect the application
and implementation of WQS (40 CFR 131.13). There are many applications
of criteria in Florida's water quality programs. Therefore, EPA
believes that it is not necessary for purposes of this proposed rule to
enumerate each of them, nor is it necessary to restate any otherwise
generally applicable requirements.
It is important to note that no existing TMDL for waters in Florida
will be rescinded or invalidated as a result of finalizing this
proposed rule, nor will this proposed rule when finalized have the
effect of withdrawing any prior EPA approval of a TMDL in Florida.
Neither the CWA nor EPA regulations require TMDLs to be completed or
revised within any specific time period after a change in water quality
standards occurs. TMDLs are typically reviewed as part of states'
ongoing water quality assessment programs. Florida may review TMDLs at
its discretion based on the State's priorities, resources, and most
recent assessments. NPDES permits are subject to five-year permit
cycles, and in certain circumstances are administratively continued
beyond five years. In practice, States often prioritize their
administrative workload in permits. This prioritization could be
coordinated with TMDL review. Because current nutrient TMDLs were
established to protect Florida's waters from the effects of nitrogen
and phosphorus pollution, the same goal as EPA's numeric nutrient
criteria, the Agency believes that, absent specific new information to
the contrary, it is reasonable to presume that basing NPDES permit
limits on those TMDLs will result in effluent limitations as stringent
as necessary to meet the federal numeric nutrient criteria.

IV. Under what conditions will EPA either not finalize or withdraw
these Federal standards?

Under the CWA, Congress gave states primary responsibility for
developing and adopting water quality standards for their navigable
waters (CWA section 303(a)-(c)). On June 13, 2012, FDEP submitted new
and revised WQS for review by the EPA pursuant to section 303(c) of the
CWA. On November 30, 2012, EPA approved the provisions of these rules
submitted for review that constitute new or revised WQS (see Section
II.F for additional information). Florida continues to have the option
to adopt and submit to EPA numeric nutrient criteria for any of the
State's Class I, Class II, and Class III waters that are not covered in
their June 13, 2012 submission to EPA, consistent with CWA section
303(c) and implementing regulations at 40 CFR 131. Although EPA is
proposing numeric nutrient criteria for Florida estuaries, coastal
waters, and south Florida inland flowing waters, if EPA approves
criteria that are legally effective under Florida law for any other
waters covered in this proposed rule as fully satisfying the CWA before
publication of the final rulemaking, EPA will not proceed with the
final rulemaking for those waters. Also, EPA will not proceed with
final rulemaking for numeric DPVs, provided that the district court
modifies the Consent Decree consistent with EPA's amended determination
that numeric DPVs are not necessary to meet CWA requirements in Florida
(see Section I.A for more information).
Pursuant to 40 CFR 131.21(c), if EPA finalizes this proposed rule,
EPA's promulgated WQS become applicable WQS for purposes of the CWA on
their effective date unless or until EPA withdraws those federally-
promulgated WQS. Withdrawing the Federal standards for the State of
Florida would require rulemaking by EPA pursuant to the requirements of
the Administrative Procedure Act (5 U.S.C.551 et seq.). EPA would
undertake such a rulemaking to withdraw the Federal criteria if and
when Florida adopts and EPA approves numeric nutrient criteria that
fully meet the requirements of section 303(c) of the CWA and EPA's
implementing regulations at 40 CFR 131. If Florida adopts and EPA
approves nutrient criteria that meet these requirements for a subset of
waters, EPA would withdraw the Federal standards for that subset of
waters.

V. Alternative Regulatory Approaches and Implementation Mechanisms

A. Designating Uses

Under CWA section 303(c)(2)(A), states shall adopt designated uses
after taking ``into consideration the use and value of water for public
water supplies, protection and propagation of fish, shellfish, and
wildlife, recreation in and on the water, agricultural, industrial and
other purposes including navigation.'' Designated uses ``shall be such
as to protect the public health or welfare, enhance the quality of
water and serve the purposes of [the CWA].'' (CWA section
303(c)(2)(A)). EPA's regulation at 40 CFR 131.3(f) defines ``designated
uses'' as ``those uses specified in water quality standards for each
water body or segment whether or not they are being attained.'' A
``use'' is a particular function of, or activity in, waters of the
United States that requires a specific level of water quality to
support it. In other words, designated uses are a state's concise
statements of its management objectives and expectations for individual
surface waters.
In the context of designating uses, states often work with
stakeholders to identify a collective goal for their waters that the
state intends to strive for as it manages water quality. States may
evaluate the attainability of these goals and expectations to ensure
they have designated appropriate uses (40 CFR 131.10(g)). EPA's
regulations at 40 CFR 131 interpret and implement CWA sections
101(a)(2) and 303(c)(2)(A) to require that states adopt designated uses
that provide water quality for the protection and propagation of fish,
shellfish, and wildlife and for recreation in and on the water
(referred to as uses specified in section 101(a)(2) of the Act),
wherever attainable (40 CFR 131.2; 131.5(a)(4); 131.6(a),(f);
131.10(g),(j)). Where states do not designate uses specified in
101(a)(2) of the Act, or remove such uses, they must demonstrate that
the uses are not attainable consistent with the use attainability
analysis (UAA) provisions of 40 CFR 131.10, specifically 131.10(g). A
state may remove protection for a use specified in CWA section
101(a)(2) if it can show, based on a UAA consistent with 131.10, that
the use is not attainable. States may include waters located in the
same watershed in a single UAA, provided that there is site-specific
information to show how each individual water fits into the group in
the context of any single UAA and how each individual water meets the
applicable requirements of 40 CFR

[[Page 74964]]

131.10(g) for removing or modifying a use.
EPA's proposed numeric nutrient criteria for estuaries, coastal
waters, and south Florida inland flowing waters will apply to those
waters designated by Florida as Class I (Potable Water Supplies), Class
II (Shellfish Propagation or Harvesting), and Class III (Recreation,
Propagation and Maintenance of a Healthy, Well-Balanced Population of
Fish and Wildlife). If Florida removes the Class I, Class II, and/or
Class III designated use for any particular water body ultimately
affected by this rule such that it is no longer designated as either
Class I, II, or III, and EPA approves such a removal because it is
consistent with CWA section 303(c) and regulations at 40 CFR 131, then
the federally-promulgated numeric nutrient criteria would not apply to
that water body. Only the water quality criteria associated with the
revised designated use would apply to that water body.

B. Variances

A variance may be described as a time-limited designated use and
criteria that target a specific pollutant(s), source(s), water
body(ies) and/or water body segment(s). Variances constitute new or
revised water quality standards subject to the procedural and
substantive requirements applicable to removing a designated use.\207\
Thus, EPA may only approve a variance if it is based on the same
factors, set out at 40 CFR 131.10(g), that are required to revise a use
specified in CWA section 101(a)(2) through a UAA.
---------------------------------------------------------------------------

\207\ In re Bethlehem Steel Corporation, General Counsel Opinion
No. 58. March 29, 1977 (1977 WL 28245 (E.P.A. G.C.)). USEPA. 1994.
Water Quality Standards Handbook: Second Edition. EPA-823-B-94-005a.
U.S. Environmental Protection Agency, Office of Water, Washington,
DC.
---------------------------------------------------------------------------

Typically, variances are time-limited, but may be renewed.
Temporarily modifying the designated use for a particular water body
through a variance process allows a state to identify an interim
designated use and associated criteria to serve as the basis for NPDES
permit limits and certifications under CWA section 401 during the term
of the variance while maintaining the designated use and associated
criteria as the ultimate goal. A state should seek a variance instead
of removing or revising the designated use where the state believes the
designated use and associated criteria can be attained at some point in
the future. By maintaining the designated use, and associated criteria,
and by specifying a point in the future when the designated use will be
fully applicable in all respects, the state ensures that further
progress will be made in improving water quality and attaining the
ultimate goal.
A variance may be written to address a specific geographic area, a
specific pollutant or pollutants, and/or a specific discharger. All
other applicable water quality standards not specifically modified by
the variance, including any other criteria adopted to protect the
designated use, remain applicable. State variance procedures, as part
of state water quality standards, must be consistent with the
substantive requirements of 40 CFR 131. Each variance must be submitted
to EPA as a revised water quality standard for review and approval or
disapproval pursuant to CWA section 303(c).
For purposes of this proposal, EPA is proposing criteria that apply
to use designations that Florida has already established. EPA believes
that the State continues to have sufficient authority under 131.10 to
grant variances under its variance procedures to Class I, Class II or
Class III uses and associated criteria. For this reason, EPA is not
proposing a Federal variance procedure.

C. Site-Specific Alternative Criteria

Site-specific alternative criteria (SSAC) are alternative values to
otherwise applicable water quality criteria that would be applied on a
watershed, area-wide, or water body-specific basis that meet the
regulatory test of protecting the water's designated use, having a
basis in sound science, and ensuring the protection and maintenance of
downstream water quality standards. SSAC may be more or less stringent
than the otherwise applicable criteria. In either case, because the
SSAC must protect the same designated use and must be based on sound
science according to the requirements of 40 CFR 131.11(a), there is no
need to modify the designated use or conduct a UAA. A SSAC may be
appropriate when additional scientific data and analyses can bring
increased precision or accuracy to expressing the concentration of a
water quality parameter that is protective of the designated use.
In EPA's 2010 rulemaking for Florida's lakes and flowing waters
outside of the South Florida Nutrient Watershed Region, EPA promulgated
a procedure whereby EPA's Region 4 Regional Administrator may establish
a SSAC after making available the proposed SSAC and supporting
documentation for public comment (40 CFR 131.43(e)). This procedure
became effective for CWA purposes on February 4, 2011. Under this
provision, any entity, including the State, can submit a proposed
Federal SSAC directly to EPA for the Agency's review and assessment as
to whether an adjustment to the applicable Federal numeric nutrient
criteria is warranted. The Federal SSAC process is separate and
distinct from the State's SSAC processes in its water quality
standards.
The current Federal SSAC procedure allows EPA to determine that a
revised site-specific chlorophyll a, TN, TP, or nitrate+nitrite numeric
criterion should apply in lieu of the generally applicable criteria
promulgated in the final rule for Florida's lakes and flowing waters
where that SSAC is demonstrated to be protective of the applicable
designated use(s). The promulgated procedure provides that EPA will
solicit public comment on its determination. Because EPA's rule
established this procedure, implementation of this procedure does not
require withdrawal of the associated federally-promulgated criteria for
the Federal SSAC to be effective for purposes of the CWA. EPA has
promulgated similar procedures for EPA's granting of variances and
SSACs in other federally-promulgated water quality standards.\208\
---------------------------------------------------------------------------

\208\ See 40 CFR 131.33(a)(3), 40 CFR 131.34(c), 40 CFR
131.36(c)(3)(iii), 40 CFR 131.38(c)(2)(v), 40 CFR 131.40(c).
---------------------------------------------------------------------------

As outlined in 40 CFR 131.43(e) and in the draft ``Technical
Assistance for Developing Nutrient Site-Specific Alternative Criteria
in Florida'' (June 2011), the process for obtaining a Federal SSAC
includes the following steps. First, an entity seeking a SSAC compiles
the supporting data, conducts the analyses, develops the expression of
the criterion, and prepares the supporting documentation demonstrating
that alternative numeric nutrient criteria are protective of the
applicable designated use. The ``entity'' may be the State, a city or
county, a municipal or industrial discharger, a permittee, a consulting
firm acting on the behalf of a client, or any other individual or
organization. The entity requesting the SSAC bears the burden of
demonstrating that any proposed SSAC meets the requirements of the CWA
and EPA's implementing regulations, specifically 40 CFR 131.11. Second,
if the entity is not the State, the entity must provide notice of the
proposed SSAC to the State, including all supporting documentation so
that the State may provide comments on the proposal to EPA. Third,
EPA's Region 4 Regional Administrator will evaluate the technical basis
and protectiveness of the proposed SSAC and decide whether to publish a
public notice and take

[[Page 74965]]

comment on the proposed SSAC. The Regional Administrator may decide not
to publish a public notice and instead return the proposal to the
entity submitting the proposal, with an explanation as to why the
proposed SSAC application did not provide sufficient information for
EPA to determine whether it meets CWA requirements or not. If EPA
solicits public comment on a proposed SSAC, upon review of comments,
the Regional Administrator may determine that the Federal SSAC is or is
not appropriate to account for site-specific conditions and make that
determination publicly available together with an explanation of the
basis for the decision.
Since the SSAC provision in EPA's 2010 rule became effective,
numerous entities have contacted EPA regarding a possible interest in
obtaining a federal SSAC. However, following discussions with EPA, it
became clear that a different water quality standards mechanism, such
as a designated use change or variance, would be more appropriate in
their particular situation. On March 9, 2011, EPA received a SSAC
request from a pulp and paper mill that discharges to the Fenholloway
River. Since the SSAC was derived from data in a nearby reference
stream, the Econfina River, the TN and TP SSAC were requested to apply
to both the Econfina and Fenholloway Rivers. Additional information was
submitted by the requestor during 2011 and 2012 to address questions
posed by EPA. At this time, EPA does not have sufficient information to
move forward with proposing or establishing the TP or TN SSAC for the
Fenholloway and Econfina Rivers.
EPA believes that there is benefit in extending this procedure for
EPA adoption of Federal SSAC that will adjust the numeric nutrient
criteria proposed in this rule. EPA is therefore proposing that a
similar procedure promulgated in 40 CFR 131.43(e) apply to estuaries,
coastal waters, and south Florida inland flowing waters. EPA requests
comment on the following proposed application of the SSAC procedure.
To successfully develop a Federal SSAC for a given estuary, coastal
water, or south Florida inland flowing water, a thorough analysis is
necessary that indicates how the alternative concentration of TN, TP,
or chlorophyll a supports both the designated use(s) of the water body
itself, and provides for the attainment and maintenance of the WQS of
downstream water bodies, where applicable. This analysis should have
supporting documentation that consists of examining indicators of
longer-term response to multiple stressors, such as seagrass health, as
well as indicators of shorter-term response specific to nitrogen and
phosphorus pollution, such as chlorophyll a concentrations associated
with balanced phytoplankton biomass or sufficient dissolved oxygen to
maintain aquatic life.
EPA is proposing seven approaches for developing SSAC for
estuaries, coastal waters, and south Florida inland flowing waters that
are similar to the four approaches EPA finalized in the 2010 rule for
Florida's lakes and flowing waters. The first five proposed approaches
are replicating the approaches EPA used to develop estuary, tidal
creek, marine lake, coastal, and south Florida inland flowing water
criteria, respectively, and applying these methods to a smaller subset
of waters or water body segments. To understand the necessary steps in
this analysis, interested parties should refer to the complete
documentation of these approaches in the Technical Support Document for
this proposed rule.
The sixth proposed approach for developing SSAC is to conduct a
biological, chemical, and physical assessment of water body conditions.
A detailed description of the supporting rationale must be included in
the documentation submitted to EPA. The components of this approach
could include, but are not limited to, evaluation of: seagrass health,
presence or absence of native flora and fauna, chlorophyll a
concentrations or phytoplankton density, average daily dissolved oxygen
fluctuation, organic versus inorganic components of total nitrogen,
habitat assessment, and hydrologic disturbance. This approach could
apply to any water body type, with specific components of the analysis
tailored for the situation.
The proposed seventh approach for developing SSAC is a general
provision for using another scientifically defensible approach that is
protective of the designated use. This provision allows applicants to
make a complete demonstration to EPA using methods not otherwise
described in the rule or its statement of basis, consistent with 40 CFR
131.11(b)(1)(iii). This approach could potentially include use of
mechanistic models or other data and information.

D. Compliance Schedules

A compliance schedule, or schedule of compliance, refers to ``a
schedule of remedial measures included in a `permit,' including an
enforceable sequence of interim requirements * * * leading to
compliance with the CWA and regulations.'' (40 CFR 122.2, CWA section
502(17)). In an NPDES permit, Water Quality-Based Effluent Limitations
(WQBELs) are effluent limits based on applicable water quality
standards for a given pollutant in a specific receiving water (NPDES
Permit Writers Manual, EPA-833-B-96-003, December, 1996). EPA
regulations provide that schedules of compliance may only be included
in permits if they are determined to be ``appropriate'' given the
circumstances of the discharge and are to require compliance ``as soon
as possible'' (40 CFR 122.47).\209\
---------------------------------------------------------------------------

\209\ Hanlon, Jim. USEPA Office of Wastewater Management. 2007,
May 10. Memorandum to Alexis Stauss, Director of Water Division EPA
Region 9, on ``Compliance Schedules for Water Quality-Based Effluent
Limitations on NPDES Permits.''
---------------------------------------------------------------------------

Florida has adopted a regulation authorizing compliance schedules.
That regulation, Subsection 62-620.620(6), F.A.C., is not affected by
this proposed rule. The complete text of the Florida rules concerning
compliance schedules is available at https://www.flrules.org/gateway/RuleNo.asp?ID=62-620.620. Florida is, therefore, authorized to grant
compliance schedules, as appropriate, under its rule for WQBELs based
on EPA's federally-promulgated numeric nutrient criteria.

VI. Economic Analysis

The CWA provides a comprehensive framework for the protection and
restoration of the health of the Nation's waters. EPA determined in
2009 that addressing the significant number of Florida waters impaired
by nitrogen and phosphorus required the establishment of numeric
nutrient criteria as part of Florida water quality standards adopted
under the CWA. State implementation of numeric nutrient criteria in the
proposed rule may result in an incremental level of controls needed for
compliance with CWA programs, or require them sooner than would occur
under current CWA programs. These controls include new or revised
National Pollutant Discharge Elimination System (NPDES) permit
conditions for point source dischargers and controls on other sources
of nitrogen and phosphorus (e.g., agriculture, urban runoff, and septic
systems) through the development of Total Maximum Daily Loads (TMDLs)
and Basin Management Action Plans (BMAPs).
EPA conducted an analysis to estimate both the increase in the
number of impaired waters that may be identified as a result of the
proposed rule, and the potential annual cost of CWA pollution control
actions likely to

[[Page 74966]]

be implemented by the State of Florida and private parties to assure
attainment of applicable State water quality designated uses. It is
important to note that the costs of pollution controls needed to attain
water quality standards for nutrients for waters already identified as
impaired by the State (including waters with and without TMDLs in
place) are not included in EPA estimates of the cost of the rule. EPA's
analysis is fully described in the document entitled Economic Analysis
of Proposed Water Quality Standards for the State of Florida's
Estuaries, Coastal Waters, and South Florida Inland Flowing Waters
(hereinafter referred to as the Economic Analysis), which can be found
in the docket and record for this proposed rule. This analysis shows
that the incremental costs associated with the proposed rule range
between $239.0 million and $632.4 million per year (2010 dollars) and
monetized benefits may be in the range from $39.0 to $53.4 million
annually.

1. NRC Review of Phase 1 Cost Estimates

On December 6, 2010 EPA published a final rule to set numeric
nutrient criteria for lakes and streams in Florida designed to protect
those waters for their State-designated uses, such as swimming,
fishing, or as drinking water sources (Phase 1 rule). EPA developed an
economic analysis to provide the public with information on potential
costs and benefits that may be associated with Florida's implementation
of EPA's rule. EPA's estimate of the annual costs of that rule ranged
from $135.5 to $206.1 million; stakeholder estimates of the same cost
categories ranged from $8 to $13 billion annually. While these costs
are not directly related to today's proposed rule, EPA determined that
an independent peer review of its economic analysis for the Phase 1
rule would provide important information on the disparity between EPA's
cost estimates and those of some stakeholders, and would be helpful to
inform and improve its analysis of today's proposed rule. Accordingly,
EPA requested the National Research Council (NRC) of the National
Academies to review EPA's economic analysis for the Phase 1 rule. The
NRC Committee completed its ``Review of the EPA's Economic Analysis of
Final Water Quality Standards for Nutrients for Lakes and Flowing
Waters in Florida'' in June. The Committee was charged with reviewing
and commenting on three specific areas:
(1) EPA's assumption that only newly impaired waters should be
analyzed,
(2) EPA's decision to estimate costs associated only with sources
affecting newly impaired waters, by sector, and
(3) EPA's assumptions about levels of control by point and nonpoint
sources, including the use of variances and other flexibilities for
more cost-effective approaches and whether to implement reverse osmosis
and other stringent control technologies.
NRC answered the first charge, agreeing with EPA's assumption that
only newly impaired waters should be analyzed. NRC also addressed the
second charge, but took exception with EPA's approach to not estimating
costs for unassessed waters or for septic systems affecting impaired
springsheds. NRC also suggested that EPA underestimated the affected
acres in agriculture. The Committee did not offer specific suggestions
for how to compute the increased acreage that should be analyzed.
However, on the cost side, they suggest including costs associated with
installation of regional treatment systems on agricultural lands.
As for the third charge, the Committee largely addressed this by
examining the details of EPA's unit costs, including comments
suggesting ways in which EPA underestimated or overestimated costs. The
Committee did not directly address EPA's assumptions regarding the use
of SSACs, variances and use designations, except to propose an
alternative cost estimating framework based on predicting the future
time path of waters progressing through the stages of listing as
impaired, TMDL development, and BMAP implementation, with and without
the rule. The Committee generally concluded that EPA's cost estimates
were likely too low, while the stakeholder estimates were too high.
In response to the NRC review, EPA has attempted to incorporate
many of the recommendations and suggestions made throughout the NRC
report including: Using the HUC-12 watershed unit of analysis;
analyzing potential costs for unassessed waters that could be
incrementally impaired; analyzing costs for each industrial plant
rather than extrapolating the results from a small sample; reviewing
actual experience from existing TMDLs to identify BMPs sufficient to
meet numeric targets; considering permeable reactive barriers for
septic systems and their installation costs; and considering
uncertainty in government expenditures. EPA has addressed these
recommendations and suggestions in this analysis of costs for the
coastal and estuary criteria.
The NRC Committee also described an approach for EPA to consider in
analyzing the impacts of its numeric nutrients criteria rules by
tracing out two time-paths of costs and benefits: one time-path for the
baseline and one reflecting the proposed rule. The costs and benefits
of the proposed rule could then be analyzed as the present value of the
difference in the two time-paths of costs and benefits, respectively.
To execute this approach, EPA would need to model not just its
projection of the eventual controls that would be implemented under the
proposed rule, but its predictions of the prioritization of watersheds
that Florida would adopt to determine the timing of controls. NRC
suggested that EPA could engage external stakeholders in a
collaborative process to determine a collective set of assumptions to
use as part of this analytical approach (or at least to ``isolate and
possibly reconcile'' areas of disagreement). EPA acknowledges the merit
of this approach, and notes that it is consistent with EPA's intent
that its numeric nutrients criteria simply interpret Florida's current
narrative nutrient criterion, by providing the often time-consuming
first step of the science-based modeling necessary for developing a
TMDL. The ultimate effect of the EPA's proposal would be to improve the
efficiency and effectiveness of Florida's WQS program with regard to
nutrients. However, given the exigencies of the consent decree and the
timing of the NRC review, EPA determined that it was not possible to
adopt the NRC's alternative approach for this proposal. The NRC's
alternative approach was presented as a finding, rather than a
recommendation, because the NRC acknowledged that time and budget
constraints might render this approach unworkable for the current rule.
Considering the exigencies, EPA took the approach of estimating
costs and benefits for a representative future year, using current
water quality data as a basis for projecting what incremental water
quality controls would need to be implemented during this future year
to meet the new criteria. An approach that compares two complete future
time-paths (with and without the proposed rule) requires taking the
difference between those two time-paths, discounting over time, and
summing in order to express the impacts in present value terms. In
contrast, EPA's approach identifies waters that would be newly
identified as impaired and the controls that would be needed to meet
the new criteria. EPA then annualizes the costs of these controls over
an appropriate time horizon. As such, the two approaches are not
directly comparable.

[[Page 74967]]

Nonetheless, EPA believes its approach sheds light on the costs and
benefits associated with its numeric nutrients criteria rules and
complies with the Executive Order requirements for conducting economic
analysis of regulations. As noted above, EPA has made significant
changes to its approach to address the NRC recommendations that are
applicable to it.

2. Baseline for Cost Analysis

EPA is promulgating numeric nutrient criteria to supplement the
State of Florida's current narrative nutrient criteria. The incremental
impacts of the proposed rule are the potential costs and benefits
associated with implementation of the proposed numeric criteria,
including DPVs, for estuaries, coastal waters, and south Florida inland
flowing waters, above and beyond the costs associated with State
implementation of its current narrative nutrient criterion. The
baseline incorporates requirements associated with restoration of
already identified impaired waters, including waters for which TMDLs
are approved and waters for which TMDLs are not yet developed. Because
the numeric nutrients criteria proposed here interpret Florida's
existing narrative criterion, which is also the basis for existing
TMDLs, the analysis assumes that these TMDLs would be adopted as site-
specific criteria. Thus, there would be no additional costs or benefits
associated with the proposed rule for these waters. The baseline for
this analysis also includes EPA's previously promulgated numeric
nutrient criteria for Florida's lakes and flowing waters.
For waters that the State of Florida has already identified as
impaired but for which it has not yet developed TMDLs, EPA expects that
the effect of this proposed rule will be to shorten the time and reduce
the resources necessary for the State of Florida to develop TMDLs and
BMAPs. For waters that the State of Florida has developed TMDLs, EPA
has looked at the proposed criteria to compare these to the target
loadings in the TMDLs and has not found a consistent pattern of
existing TMDLs being either more or less stringent than would be
required to meet the criteria proposed in this rule. For already
impaired waters and waters already under a TMDL, EPA assumed that no
additional controls on nonpoint sources to these waters would be needed
as a consequence of this rule. However, there may be an incremental
impact of the proposed rule for any point source dischargers to these
waters that have or may receive waste load allocations for just one
nutrient pollutant if those waters are not attaining criteria for the
other as a result of this proposed rule. These costs are included in
this economic analysis.
For waters not currently impaired under the baseline, EPA uses
current water quality measurements to predict which waters would be
deemed unimpaired as a result of the proposed rule (and therefore need
not be analyzed for nonpoint source control costs). EPA acknowledges
that these conditions could change in the future. To the extent that
the experience in implementation of the proposed rule deviates from
these specific assumptions about the baseline, EPA's estimates of the
costs and benefits may be under- or overestimated. See Section 2 of the
Economic Analysis for a full description of the baseline. EPA requests
comment on its assumptions regarding the baseline.

3. Incremental Costs

The likely effect of this proposed rule will be the assessment and
identification of additional waters that are impaired and not meeting
the numeric water quality criteria in the proposed rule. The
incremental impact of the proposed rule includes the costs for controls
on point and nonpoint sources, developing and implementing TMDLs to
attain the proposed criteria, and the monetary value (benefits) of the
resulting potential increase in water quality. The economic analysis
describes these potential incremental impacts of the proposed rule. It
is important to note that EPA took care not to include costs for the
estuarine and coastal marine waters contained in Florida's newly-
approved State WQS.
To develop these estimates, EPA first assessed State control
requirements associated with current water quality, existing impaired
waters, and existing TMDLs, as well as existing regulations specific to
estuaries, coastal waters and south Florida inland flowing waters (the
baseline). EPA then identified the costs and benefits associated with
additional pollution controls to meet EPA's proposed numeric criteria,
beyond pollution controls currently needed or in place. To estimate
incremental costs to municipal and industrial dischargers, EPA gathered
publicly available facility information and data on potential control
technologies, and used Florida Department of Environmental Protection
(FDEP) point source implementation procedures to estimate the change in
WQBELs and treatment controls that could result from the proposed rule.
EPA assessed potential non-point source control costs by using publicly
available information and data to determine land uses near waters that
would likely be identified as impaired under the proposed rule. EPA
used current FDEP data on stormwater controls and Florida Department of
Agricultural and Consumer Services (FDACS) manuals to estimate costs of
implementing stormwater and agricultural best management practices
(BMPs) to attain the proposed numeric criteria. EPA also estimated the
potential costs associated with upgrades of homeowner septic systems
and potential government costs of developing additional TMDLs for water
identified as impaired under this rule. Finally, EPA qualitatively and
quantitatively described and estimated some of the potential benefits
of complying with the new water quality standards. Although it is
difficult to predict with certainty how the State of Florida will
implement these new water quality standards, the result of this
analysis represent EPA's best estimates of costs and benefits of the
State of Florida's likely actions to implement this proposed rule.
A. Incrementally Impaired Waters
Compared to current conditions, potentially incrementally impaired
waters are those waters that exceed EPA's proposed criteria for which
FDEP has not already developed a TMDL or listed as impaired for
nutrients. To estimate incremental costs associated with attainment of
criteria, EPA first removed any waters for which the State of Florida
has already determined to be impaired or established a TMDL and/or
BMAP, because it considers these waters part of the baseline for this
analysis. BMAPs are iterative and are updated on a continual basis
until the TMDL targets are met. EPA assumes that controls will be
implemented through these mechanisms until the TMDLs are met. Although
additional costs to address baseline impairments may be needed in the
future (after this rule is promulgated), EPA does not believe that
these costs should be attributed to this proposed rule, but are instead
part of the baseline. As discussed above, the State of Florida is not
required to revise any existing TMDL as a result of this rule, and
WQBELs in NPDES permits that are consistent with an existing EPA
approved TMDL meet the requirements of the CWA. TMDL nutrient criteria
have been shown to be both more stringent and less stringent when
compared to criteria under this proposed rule and EPA has provided
SSACs as a mechanism to approve the standards in existing TMDLs and
BMAPs. Thus, EPA does not anticipate that this rule will result in
increased nonpoint source controls costs for

[[Page 74968]]

watersheds that already have an EPA-approved TMDL.
After excluding waters already identified as impaired under
Florida's existing narrative criteria, EPA next identified estuarine
and coastal segments that do not meet the numeric criteria of this
proposed rule. EPA then assumed identified waterbodies (WBIDs \210\)
that overlap those segments may be identified as incrementally
impaired. EPA then identified the watersheds that contain or surround,
in the case of coastal waters, those incrementally impaired WBIDs.
---------------------------------------------------------------------------

\210\ WBID is a waterbody identification number assigned by
Florida, in order to delineate the boundaries of Florida's waters.
---------------------------------------------------------------------------

EPA analyzed FDEP's database of ambient water quality monitoring
data and compared monitoring data for each segment with EPA's proposed
criteria for TN and TP to identify incrementally impaired waters. EPA
compiled the most recent five years of monitoring data and determined
if there was sufficient data available to calculate more than one
annual geometric mean in a consecutive three year period. With
sufficient data, EPA calculated the annual geometric mean for each
segment identified by EPA segment boundaries, and identified waters as
incrementally impaired if they exceeded the applicable criteria in this
proposed rule. The results of this analysis are shown in Table VI(A).

Table VI(A)(1)--Number of WBIDs Summary of Data Analysis for Proposed Criteria \1\
----------------------------------------------------------------------------------------------------------------
Not currently impaired
under the baseline
Baseline --------------------------
Criteria type impaired Data Total
\2\ available Data not
\3\ available
----------------------------------------------------------------------------------------------------------------
Coastal..................................................... 0 5 68 73
Estuaries................................................... 42 121 95 258
---------------------------------------------------
Total................................................... 42 126 163 331
----------------------------------------------------------------------------------------------------------------
Source: FDEP IWR run 44.
\1\ Represents number of WBIDs, based on 10% of WBID area overlapping segments for which EPA is proposing
numeric nutrient criteria.
\2\ On 303(d) list as impaired for nutrients or covered under a nutrient-related TMDL. EPA did not assess these
waters further for attainment of the proposed criteria.
\3\ WBIDs in segments for which at least two geometric means in a consecutive three year period can be
calculated based on having at least four samples in a given year, with one sample in winter and summer.

Controls may also be needed to meet the proposed criteria in a
portion of the 163 WBIDs for which EPA does not have data if subsequent
data would indicate impairment. These 163 WBIDs are variously located
in the same watersheds as WBIDs that are baseline impaired or
incrementally impaired by this proposed rule, or in watersheds either
with no known impaired WBIDs or for which none of the WBIDs have
sufficient data to determine impairment status. Without additional
information about these waters, EPA determined the number of impaired-
though-unassessed waters as a range. As a low estimate, it is possible
that none of the unassessed waters would be impaired. Given the
targeting scheme for Florida's IWR data, these unassessed waters likely
have a lower probability of impairment than assessed waters, and zero
represents the lower bound. For the high end of the range, EPA
considered a proportional impairment rate of assessed waters. The
impairment rate of unassessed waters may be anywhere in between.
While helpful in establishing the number of waterbodies that may be
incrementally impaired, the assumption of proportional impairment does
not produce information on location needed to estimate associated
costs. The majority of unassessed waters lie along the coast and in
close proximity to baseline impaired and impaired assessed waters.
Hence, for this analysis, EPA assumed that impairment in unassessed
waters would most likely be near baseline impairments and impaired
assessed waters, since the loads causing impairment in these assessed
waters could also affect the downstream unassessed waters. For coastal
waters and south Florida waters, EPA used GIS to locate waters within
or adjacent to the same watersheds associated with baseline impairments
and impaired assessed waters. For estuaries, the number of unassessed
waters estimated to be impaired (based on the assumption of
proportional impairment) would not fit within the same watersheds
associated with baseline impairments and impaired assessed waters.
Therefore, EPA used GIS analysis to identify a buffer around the
watersheds associated with baseline impairments and impaired assessed
waters that would just include the estimated number of impaired
unassessed waters. EPA found that a buffer size of 0.7 miles
encompassed the estimated number of impaired unassessed waters. A
smaller buffer (e.g., 0.5 mile) would not include enough unassessed
waters. A larger buffer (e.g., 1 mile) would include too many
unassessed waters. EPA then used this 0.7 mile buffer to identify the
associated incremental watersheds that may need nonpoint source
controls. EPA has estimated the acres of various land uses within these
watersheds and reported as the upper bound in the Additional Unassessed
Water column of Table VI(A)(2).

[[Page 74969]]

Table VI(A)(2)--Summary of Land Use in Incrementally Impaired Watersheds for the Analysis of Costs Under the
Proposed Rule
[Acres]
----------------------------------------------------------------------------------------------------------------
Additional
Land use type Assessed waters \1\ unassessed water \2\ Total
----------------------------------------------------------------------------------------------------------------
Agriculture................................... 15,312 0-22,828 15,312-38,140
Communications and Utilities.................. 3,337 0-3,315 3,337-6,652
Forest........................................ 199,432 0-256,137 199,432-455,569
Industrial.................................... 2,025 0-6,703 2,025-8,729
Other......................................... 9,276 0-11,306 9,276-20,582
Transportation Corridors...................... 9,177 0-3,636 9,177-12,813
Urban......................................... 128,787 0-86,508 128,787-215,295
Water......................................... 220,728 0-102,615 220,728-323,343
Wetlands...................................... 196,545 0-322,355 196,545-518,899
-----------------------------------------------------------------
Total..................................... 784,619 0-815,403 784,619-1,600,022
----------------------------------------------------------------------------------------------------------------
\1\ Total acreage of 12-digit HUC watersheds surrounding the incrementally impaired WBIDs based on sufficient
data, excluding watersheds for which EPA has already estimated a need for controls.
\2\ Acreage surrounding potential incrementally impaired unassessed waters not associated with baseline
impairment or incremental impairment under the proposed rule based on sufficient data.

The costs associated with the additional controls that would be
necessary in the watersheds not already included in the cost analysis
because of known incremental impaired waters will be included in the
remainder of this section.
B. Point Source Costs
Point sources of wastewater must have a National Pollution
Discharge Elimination System (NPDES) permit to discharge into surface
waters. EPA identified point sources potentially discharging nitrogen
and phosphorus to estuaries, coastal waters, and south Florida inland
flowing waters by evaluating the Integrated Compliance Information
System-National Pollutant Discharge Elimination System (ICIS-NPDES)
database. EPA identified all facilities with any permitted discharge to
estuarine, coastal, and south Florida inland flowing waters with an
existing effluent limit or monitoring requirement for nitrogen or
phosphorus, as well as those with the same industry code as any point
source with an identified nutrient monitoring requirement. This
analysis identified 121 point sources as having the potential to
discharge nitrogen and/or phosphorus. Table VI(B) summarizes the number
of point sources with the potential to discharge nitrogen and/or
phosphorus.

Table VI(B)--NPDES-Permitted Wastewater Dischargers Potentially Affected by Proposed Rule
----------------------------------------------------------------------------------------------------------------
Major Minor
Discharger Category Dischargers Dischargers Total
\a\ \b\
----------------------------------------------------------------------------------------------------------------
Municipal Wastewater............................................ 53 31 84
Industrial Wastewater........................................... 19 18 37
-----------------------------------------------
Total....................................................... 72 49 121
----------------------------------------------------------------------------------------------------------------
\a\ Facilities discharging greater than one million gallons per day or likely to discharge toxic pollutants in
toxic amounts.
\b\ Facilities discharging less than one million gallons per day and not likely to discharge toxic pollutants in
toxic amounts.

1. Municipal Waste Water Treatment Plant (WWTP) Costs
EPA considered the costs of known nitrogen and phosphorus treatment
options for municipal WWTPs. Nitrogen and phosphorus removal
technologies that are available can reliably attain annual average
total nitrogen (TN) concentration of approximately 3.0 mg/L or less and
annual average total phosphorus (TP) concentration of approximately 0.1
mg/L or less.\211\ EPA considered wastewater treatment to these
concentrations to be the target levels for the purpose of this
analysis. The NRC suggested that there is uncertainty associated with
this assumption because dischargers to impaired waters typically
receiving WQBELs equal to the numeric water quality criteria (NRC,
2012; p. 48). However, procedures for determining appropriate WQBELs
include an evaluation of effluent quality and assimilative capacity of
the receiving water. Specifically for nutrients, EPA found no
implementation evidence in Florida to support the assumption that the
criteria would be adopted as end-of-pipe limits. Instead, based on the
State of Florida protocol \212\ and the examples from existing nutrient
TMDLs, EPA assumed for this analysis that state implementation of the
proposed rule will not result in criteria end-of-pipe effluent
limitations for municipal WWTPs.
---------------------------------------------------------------------------

\211\ U.S. EPA, 2008, ``Municipal Nutrient Removal Technologies
Reference Document. Volume 1--Technical Report,'' EPA 832-R-08-006.
\212\ Florida Department of Environmental Protection (FDEP).
2006a. TMDL Protocol. Version 6.0. Task Assignment 003.03/05-003.
---------------------------------------------------------------------------

The NPDES permitting authority determines the need for WQBELs for
point sources on the basis of determining their reasonable potential to
exceed water quality criteria. To determine reasonable potential on a
facility-specific basis, data such as instream nutrient concentrations
and low flow conditions would be necessary. However, because most WWTPs
are likely to discharge nutrients at concentrations above applicable TN
and/or TP criteria, EPA assumed that all WWTPs have reasonable
potential to exceed the numeric criteria. The NRC supported this
assumption.
For municipal wastewater, EPA estimated costs to reduce effluent

[[Page 74970]]

concentrations to 3 mg/L or less for TN and 0.1 mg/L or less for TP
using advanced biological nutrient removal (BNR). Although reverse
osmosis and other treatment technologies may have the potential to
reduce nitrogen and phosphorus concentrations even further, EPA
believes that implementation of reverse osmosis applied on such a large
scale has not been demonstrated.\213\ The NRC supported this assumption
(NRC, 2012; p. 46) but said that in some instances, treatment to levels
beyond the controls of advanced BNR would be required (NRC, 2012; p.
48). Such levels have not been required for WWTPs by the State of
Florida in the past, including for those WWTPs under TMDLs with
nutrient targets comparable to the criteria in this proposed rule. EPA
believes that should state-of-the-art BNR technology, together with
other readily available and effective physical and chemical treatment
(including chemical precipitation and filtration), fall short of
compliance with permit limits associated with meeting the new numeric
nutrient criteria, then it is reasonable to assume that entities would
first seek out alternative compliance mechanisms such as reuse, site-
specific alternative criteria, variances, and designated use
modifications. In addition, under a TMDL, FDEP could allocate greater
load reductions to nonpoint sources based on baseline contributions and
existing controls, thus resulting in fewer reductions required from
point source dischargers. EPA acknowledges that if its assumptions
about the availability of reuse, SSACs, variances and designated use
changes are incorrect, then the costs presented here are
underestimates.
---------------------------------------------------------------------------

\213\ Treatment using reverse osmosis also requires substantial
amounts of energy and creates disposal issues as a result of the
large volume of concentrate generated.
---------------------------------------------------------------------------

To estimate compliance costs for WWTPs, EPA identified current WWTP
treatment capabilities using FDEP's Wastewater Facility Regulation
(WAFR) database, and information obtained from NPDES permits and/or
water quality monitoring reports. Table VI(B)(1) summarizes EPA's best
estimate of the number of potentially affected municipal WWTPs that may
require additional treatment for nitrogen and/or phosphorus to meet the
numeric criteria supporting State designated uses.
---------------------------------------------------------------------------

\214\ Florida Department of Environmental Protection (FDEP).
2009. Wastewater Facility Information: Wastewater Facility
Regulation (WAFR) database. http://www.dep.state.fl.us/water/wastewater/facinfo.htm. Accessed June 2009.

Table VI(B)(1)--Summary of Potential for Additional Nutrient Controls for Municipal Wastewater Treatment Plants
\a\
----------------------------------------------------------------------------------------------------------------
Number of dischargers
-------------------------------------------------------------------------------
Discharge type Additional Additional Additional No incremental
reduction in reduction in reduction in controls Total
TN and TP \a\ TN only \b\ TP only \c\ needed \d\
----------------------------------------------------------------------------------------------------------------
Major........................... 7 0 22 22 51
Minor........................... 17 0 1 10 28
-------------------------------------------------------------------------------
Total....................... 24 0 23 32 79
----------------------------------------------------------------------------------------------------------------
Source: Based on treatment train descriptions in FDEP's Wastewater Facility Regulation database \214\ and
permits, WLAs in TMDLs and existing regulations, assuming dischargers would have to install advanced BNR for
compliance under the rule.
\a\ Includes dischargers without treatment processes capable of achieving the target levels or existing WLA for
TN and TP, or for which the treatment train description is missing or unclear.
\b\ Includes dischargers with chemical precipitation only.
\c\ Includes dischargers with Modified Ludzack-Ettinge (MLE), four-stage Bardenpho, and BNR specified to achieve
less than 3 mg/L, or those with WLA under a TMDL for TN only.
\d\ Includes dischargers with anaerobic-anoxic oxidation (A\2\/O), modified Bardenpho, modified University of
Cape Town (UCT), oxidation ditches, or other BNR coupled with chemical precipitation, those with WLAs under a
TMDL for both TN and TP, those discharging to waters on the 303(d) list for nutrients or DO, and those ocean
dischargers covered under the Grizzle-Figg Act that will cease discharge completely by 2025.

An EPA study provides unit cost estimates for BNR for various TN
and TP performance levels.\215\ To estimate costs for WWTPs, EPA used
the average capital and average operation and maintenance (O&M) unit
costs for technologies that achieve an annual average of 3 mg/L or less
for TN and/or 0.1 mg/L or less for TP. NRC noted that these unit costs
were significantly lower than those estimated by the Florida Water
Environment Association Utility Council (FWEAUC) and suggested to
verify the unit costs against FWEAUC's unit costs. Multiplying these
unit costs by facility flow reported in EPA's PCS database, EPA
estimated that total costs could be approximately $44.1 million per
year (2010 dollars).\216\
---------------------------------------------------------------------------

\215\ USEPA. 2008. Municipal Nutrient Removal Technologies
Reference Document. Volume 1--Technical Report. EPA 832-R-08-006.
U.S. Environmental Protection Agency, Office of Wastewater
Management, Municipal Support Division.
\216\ Estimated capital costs annualized at 7% over 20 years,
plus estimated annual O&M.
---------------------------------------------------------------------------

EPA also conducted a sensitivity analysis to address the potential
for dischargers under TMDLs that establish WLAs for TN or TP (and not
both pollutants), such that incremental costs could be required under
the proposed rule to control the other pollutant. The results of this
analysis suggest a range of additional costs from $3.6 million to $5.6
million annually (see section 5.3 of the Economic Analysis). Thus,
estimated total cost could range from approximately $47.7 million to
$49.7 million per year.
2. Industrial Point Source Costs
Incremental costs for industrial dischargers are likely to be
facility-specific and depend on process operations, existing treatment
trains, and composition of waste streams. EPA identified 36 industrial
dischargers potentially affected by the proposed rule. Of those, 4 are
subject to an existing nutrient TMDL, and 4 discharge to waters
currently listed as impaired. As with WWTPs, EPA assumed that costs to
industrial dischargers under an existing nutrient TMDL with WLAs for
both nitrogen and phosphorus and costs at facilities discharging to
currently impaired waters are not attributable to this proposed rule
because those costs would be incurred absent the rule (under the
baseline).
To estimate potential costs to the remaining 28 potentially
affected industrial facilities (Table VI(B)(2)), EPA used effluent data
for flows, TN, and TP

[[Page 74971]]

from Discharge Monitoring Reports in EPA's ICIS-NPDES database and
other information in NPDES permits to determine whether or not they
have reasonable potential to cause or contribute to an exceedance of
the proposed criteria in this proposed rule. Because the numeric
nutrient criteria are annual geometric means, EPA assumed that any
discharger with an average TN or TP concentration greater than the
proposed criterion would have reasonable potential. For those
facilities with reasonable potential, EPA further analyzed their
effluent data and estimated potential revised water quality based
effluent limits (WQBELs) for TN and TP. If the data indicated that the
facility would not be in compliance with the revised WQBEL, EPA
estimated the additional nutrient controls those facilities would
likely implement to allow receiving waters to meet designated uses and
the costs of those controls. Although reverse osmosis and other
treatment technologies have the potential to reduce nitrogen and
phosphorus concentrations even further, EPA believes that
implementation of reverse osmosis applied on such a large scale has not
been demonstrated as likely or necessary.\217\ If BNR or other more
conventional cost-effective treatment technologies would not meet the
revised WQBELs, EPA believes it is reasonable to assume that entities
would first seek out other available compliance mechanisms such as
reuse, site-specific alternative criteria, variances, and designated
use modifications. In addition, under a TMDL FDEP could allocate
greater load reductions to nonpoint sources based on baseline
contributions resulting in fewer reductions from point source
dischargers.
---------------------------------------------------------------------------

\217\ Treatment using reverse osmosis also requires substantial
amounts of energy and creates disposal issues as a result of the
large volume of concentrate that is generated.
---------------------------------------------------------------------------

Using this method, EPA estimated that the potential costs for
industrial dischargers could be approximately $15.2 million annually
(2010 dollars). Note that a number of the dischargers would not incur
incremental costs, while others would incur costs of implementing
controls such as chemical precipitation, filtration, and/or BNR. NRC
said that the use of similar unit costs for industrial flows as EPA had
used for municipal waste water treatment facilities did not capture the
higher costs associated with lower flows and therefore industrial costs
are underestimated. The source EPA used to find unit costs included
plant costs with low flows that EPA was able to compare to plant costs
with high flows, as NRC suggested. EPA found no pattern for higher or
lower costs and therefore did not change its unit costs. The NRC also
suggested EPA should include costs for flow equalization at some
industrial facilities. EPA does not have enough flow data to estimate
flow equalization costs, but did use the 90th percentile flows as the
basis for costs for dischargers with variable flows (see Cost
Calculations for Industrial Dischargers). EPA considers the use of the
90th percentile flow together with an allowance for contingencies to
provide sufficient costs allowance to cover the cost of equalization
should that be necessary at individual facilities.

Table VI(B)(2)--Potential Incremental Costs for Industrial Dischargers \a\
----------------------------------------------------------------------------------------------------------------
Number of Total annual
Industrial category Total number facilities costs (million
of facilities with costs \b\ 2010$/yr)
----------------------------------------------------------------------------------------------------------------
Chemicals and Allied Products................................... 1 0 $0.0
Electric Services............................................... 8 2 0.5
Food............................................................ 2 1 0.2
Mining.......................................................... 0 0 0.0
Other........................................................... 14 1 0.0
Pulp and Paper.................................................. 3 3 14.5
-----------------------------------------------
Total....................................................... 28 7 15.2
----------------------------------------------------------------------------------------------------------------
\a\ May not add due to rounding.
\b\ In most cases, only a few facilities are projected to incur costs; others do not.

C. Non-Point Source Costs
To estimate the potential incremental costs associated with
controlling nitrogen and phosphorus pollution from non-point sources,
EPA identified land areas near incrementally impaired waters using GIS
analysis. EPA identified the 12-digit hydrologic units (HUC-12s) in
Florida that contain, or in the case of coastal waters, surround an
incrementally impaired WBID (WBIDs are GIS polygons for water
assessment), and excluded those HUC-12s that are included in the
baseline or cost analysis for in the Inland Rule. EPA then identified
all the 12-digit HUCs that drain to any remaining unassessed WBIDs that
may become incrementally impaired should they be assessed in the
future. EPA then identified land uses in these HUCs using GIS analysis
of data obtained from the State of Florida. By using the HUC-12
delineation, EPA has addressed the NRC recommendation that EPA use the
more refined HUC-12 delineation instead of the larger HUC-10
delineation.
1. Costs for Urban Runoff
EPA's GIS analysis indicates that urban land (excluding land for
industrial uses covered under point sources) accounts for approximately
128,800 acres to 215,300 acres of the land near incrementally impaired
waters. EPA's analysis indicates that urban runoff is already regulated
on a portion of this land under EPA's stormwater program requiring
municipal separate storm sewer system (MS4) NPDES permits. Florida has
a total of 27 large (Phase I) permitted MS4s serving greater than
100,000 people and 132 small (Phase II) permitted MS4s serving fewer
than 100,000 people. MS4 permits generally do not have numeric nutrient
limits, but instead rely on implementation of BMPs to control
pollutants in stormwater to the maximum extent practicable. Even those
MS4s in Florida discharging to impaired waters or under a TMDL
currently do not have numeric limits for any pollutant.
In addition to EPA's stormwater program, several existing State
rules are intended to reduce pollution from urban runoff and were
included in the baseline for EPA's proposed rule. For

[[Page 74972]]

example, Florida's Urban Turf Fertilizer rule (administered by FDACS)
requires a reduction in the amount of nitrogen and phosphorus that can
be applied to lawns and recreational areas. Florida's 1982 stormwater
rule (Chapter 403 of Florida statues) requires stormwater from new
development and redevelopment to be treated prior to discharge through
the implementation of BMPs. The rule also requires that older systems
be managed as needed to restore or maintain the beneficial uses of
waters, and that water management districts establish and implement
other stormwater pollutant load reduction goals. In addition, the
``Water Resource Implementation Rule'' (Chapter 62-40, F.A.C.)
establishes that stormwater design criteria adopted by FDEP and the
water management districts shall achieve at least 80% reduction of the
average annual load of pollutants that cause or contribute to
violations of water quality standards (95% reduction for outstanding
natural resource waters). This rule sets design criteria for new
development that is not based on impairment status of downstream
waters. For NPDES permits, reasonable potential exists for any effluent
concentrations above the criteria even if the water is attaining
standards. Therefore, EPA assumed that post-1982 developed land already
has controls to meet 80% reductions and only older developed land would
need an incremental level of control. The rule also states that the
pollutant loadings from older stormwater management systems shall be
reduced as necessary to restore or maintain the designated uses of
waters. As the proposed numeric nutrients criteria interpret the
existing narrative criterion, EPA assumes any such reductions requiring
costs are not a consequence of the proposed criteria. The NRC suggested
that existing State rules are not being fully complied with and EPA
should not consider them to be part of the baseline. EPA's assumption
of compliance with the 1982 Stormwater Rule is based on FDEP's economic
analysis indicating that post-1982 development would not need
additional controls. Given the State's cyclical monitoring schedule,
existing ambient monitoring data may not yet fully reflect nutrient
reductions because the rule has only been in effect since July 2009.
Other controls that target the quantity of stormwater runoff from low-
density residential land may not be as cost effective as the Urban Turf
Fertilizer Rule. Thus, EPA did not estimate an incremental level of
control to be needed for low-density residential land.
Identifying water as impaired under the proposed rule could result
in changes to MS4 NPDES permit requirements for urban runoff, so that
Florida waters meet the proposed criteria. However, the combination of
additional pollution controls required will likely depend on the
specific nutrient reduction targets, the controls already in place, and
the relative amounts of nitrogen and phosphorus pollution contained in
urban runoff at each particular location. Because stormwater programs
are usually implemented using an iterative approach--with the
installation of controls followed by monitoring and re-evaluation--
estimating the complete set of pollution controls required to meet a
particular water quality target would require detailed site-specific
analysis.
Although it is difficult to predict the complete set of potential
additional stormwater controls that may be required to meet the numeric
criteria that supports State designated uses in incrementally impaired
waters, EPA estimated potential costs for additional treatment by
assessing the amount of urban land that may require additional
stormwater controls. FDEP has previously assumed that all urban land
developed after adoption of Florida's 1982 stormwater rule would be in
compliance with the Phase 1 rule and EPA believes it is reasonable to
make a similar assumption for this proposed rule.\218\ Using this
assumption, EPA used GIS analysis of land use data obtained from the
State of Florida \219\ to identify the amount of remaining urban land
located near incrementally impaired waters. For Phase I MS4s, EPA used
a range of acres with 46,700 acres as the upper bound and zero acres as
the lower bound, because Phase I MS4 urban areas already must implement
controls to the ``maximum extent practicable.'' As such, these
municipalities may not need to achieve additional reductions if
existing requirements are already fully implemented. EPA similarly
estimated ranges of acreage needing stormwater controls for Phase II
MS4 areas, and non-MS4 urban areas. GIS analysis of land use data
indicates that land in Phase II MS4 and non-MS4 urban areas are low
density residential. For the urban land that is not low density
residential, some additional structural BMPs may be necessary to comply
with EPA's numeric nutrient criteria. Because nutrient reductions from
low density residential land under the existing Urban Turf Fertilizer
Rule are likely sufficient, and the State of Florida asserts that urban
land developed after 1982 (77.9% of urban land) would not need
additional controls for compliance with EPA's numeric nutrient
criteria, EPA estimated that approximately 27,700 to 43,100 acres of
Phase II MS4 urban land and 19,600 to 28,900 acres of urban land
outside of MS4 areas may require additional stormwater controls to meet
EPA's numeric nutrient criteria. The actual acreage may be somewhere
within the range. Using this procedure, EPA estimated that 47,300 to
118,700 acres may require additional stormwater controls.
---------------------------------------------------------------------------

\218\ FDEP. 2010. FDEP Review of EPA's ``Preliminary Estimate of
Potential Compliance Costs and Benefits Associated with EPA's
Proposed Numeric Nutrient Criteria for Florida'': Prepared January
2010 by the Environmental Protection Agency. Florida Department of
Environmental Protection, Division of Environmental Assessment and
Restoration.
\219\ Florida Geographic Data Library, 2009.
---------------------------------------------------------------------------

The cost of stormwater pollution controls can vary widely. FDEP
tracks the cost of stormwater retrofit projects throughout the State
that it has provided grant funding for.\220\ EPA estimated control
costs based on the average unit costs, $19,300, across all projects
from FDEP (2012c) to account for the mix of project types likely to be
installed based on their current prevalence in grant funding throughout
the state. The NRC suggested that higher pollutant removals may be
obtained by more advanced stormwater control measures such as
bioretention or other vegetated infiltration, which may be more costly
than the current set of FDEP-funded projects. NRC (2009) indicates
annual per-acre costs could range from $300 per acre to $3,500 per
acre.\221\ EPA does not have the necessary information to exactly
compare this source with EPA's average unit costs of $19,300, but
believes EPA's unit costs are captured within the higher end of the
range. Given that the costs may be comparable to the NRC suggested
projects and the retrofit data is specific to projects that Florida has
already implemented therefore making them more likely to be implemented
for future projects, EPA continues to use costs from the Florida
specific retrofit project data.
---------------------------------------------------------------------------

\220\ FDEP. 2010. ``Appendix 3: Cost Analysis for Municipal
Discharge using 30 Year Annualization and Florida MS4 Numeric
Nutrient Criteria Cost Estimation,'' In: FDEP Review of EPA's
``Preliminary Estimate of Potential Compliance Costs and Benefits
Associated with EPA's Proposed Numeric Nutrient Criteria for
Florida'': Prepared January 2010 by the Environmental Protection
Agency. Florida Department of Environmental Protection, Division of
Environmental Assessment and Restoration.
\221\ NRC (2009) does not provide the discount rate, useful
life, or annual O&M costs it uses to estimate annual costs.

---------------------------------------------------------------------------

[[Page 74973]]

EPA multiplied the average capital costs per acre ($19,300) of the
FDEP projects by the number of acres potentially requiring controls to
estimate the potential incremental stormwater capital costs associated
with the proposed rule. EPA then used FDEP's estimate of operation and
maintenance (O&M) costs (at 5% of capital costs), and annualized
capital costs using FDEP's discount rate of 7% over 20 years. This
analysis indicates that urban runoff control costs could range from
approximately $131.9 million to $330.9 million. Table VI(C)(2)
summarizes these estimates.

Table VI(C)(1)--Estimated Incremental Urban Stormwater Costs
----------------------------------------------------------------------------------------------------------------
Estimated acres
potentially Capital costs O&M costs Annual costs
Urban land type needing controls (million $) \2\ (million $/yr) \3\ (million $/yr) \4\
\1\
----------------------------------------------------------------------------------------------------------------
MS4 Phase I Urban............... 0-46,700 $0-$901.4 $0-$45.1 $0.0-$130.2
MS4 Phase II Urban.............. 27,700-43,100 534.0-832.8 26.7-41.6 77.1-120.3
Non-MS4 Urban................... 19,600-28,900 379.2-557.5 19.0-27.9 54.8-80.5
-------------------------------------------------------------------------------
Total....................... 47,300-118,700 913.2-2,291.7 45.7-114.6 131.9-330.9
----------------------------------------------------------------------------------------------------------------
\1\ Phase I MS4s range represents implementation of BMPs to the MEP resulting in compliance with EPA's rule or
controls needed on all pre-1982 developed land that is not low density residential; Phase II MS4s and urban
land outside of MS4s represent controls needed on all pre-1982 developed land that is not low density
residential. Assumes that up to 46% of land associated with unassessed waters would require controls.
\2\ Represents acres needing controls multiplied by median unit costs of stormwater retrofit costs from FDEP
(2010b).
\3\ Represents 5% of capital costs.
\4\ Capital costs annualized at 7% over 20 years plus annual O&M costs.

2. Agricultural Costs
EPA's GIS analysis of land use indicates that agriculture accounts
for about 15,312 to 38,140 acres of land near incrementally impaired
waters. This differs substantially from the Inland Rule where over
800,000 acres of agricultural land use were identified in watersheds
draining to potentially incrementally impaired WBIDs, because
agriculture is a much more prevalent land use inland than near the
coast. Agricultural runoff can be a source of nitrogen and phosphorus
to estuaries, coastal waters and south Florida inland flowing waters
through the application of fertilizer to crops and pastures and from
animal wastes. For waters impaired by nitrogen and phosphorus
pollution, the 1999 Florida Watershed Restoration Act established that
agricultural BMPs should be the primary instrument to implement TMDLs.
Thus, additional waters identified by the State as impaired under the
proposed rule may result in State requirements or provisions to reduce
the discharge of nitrogen and/or phosphorus to incrementally impaired
waters through the implementation of BMPs. The NRC suggested that for
Phase I, the incremental agricultural land area identified was likely
underestimated. EPA addressed this finding by including land area
associated with potentially impaired unassessed waters in this
analysis.
EPA estimated the potential costs of additional agricultural BMPs
by evaluating land use data. BMP programs designed for each type of
agricultural operation and their costs were taken from a study of
agricultural BMPs to help meet TMDL targets in the Caloosahatchee
River, St. Lucie River, and Lake Okeechobee watersheds. Three types of
BMP programs were identified in this study. The first program, called
the ``Owner Implemented BMP program,'' consists of a set of BMPs that
land owners might implement without additional incentives. The second
program, called the ``Typical BMP program,'' is the set of BMPs that
land owners might implement under a reasonably funded cost share
program or a modest BMP strategy approach. The third program, called
the ``Alternative BMP program,'' is a more expensive program designed
to supplement the ``Owner Implemented BMP program'' and ``Typical BMP
program'' if additional reductions are necessary.
The BMPs in the ``Owner Implemented BMP Program'' and ``Typical BMP
Program'' are similar to the BMPs verified as effective by FDEP and
adopted by FDACS. EPA did not find BMPs in the ``Alternative BMP
Program'' similar to the BMPs in the FDACS BMP manual, despite the NRC
suggestion that the ``Alternative BMP Program'' would be needed to meet
NNC. EPA has also found no indication that the ``Alternative BMP
Program,'' which includes edge-of-farm stormwater chemical treatment,
has been implemented through TMDLs to meet water quality standards for
nutrients in watersheds with significant contributions from agriculture
(e.g., Lake Okeechobee). EPA also found that TMDLs cite the Florida
Department of Agriculture and Consumer Services' (FDACS) BMP manual as
a source of approved BMPs. Therefore, for purposes of this analysis,
EPA believes it is reasonable to assume that nutrient controls for
agricultural sources are best represented by the combination of the
``Owner Implemented BMP Program'' and ``Typical BMP Program'' and not
the more stringent ``Alternative BMP Program'' controls. This
assumption corroborates EPA's intent for the nutrient criteria to
provide the same level of protection as Florida's narrative criteria.
Table VI(C)(2) summarizes the potential incremental costs of BMPs
on agricultural lands in the watersheds of incrementally impaired
estuaries, coastal waters and south Florida inland flowing waters for
each agricultural category. This analysis indicates that incremental
agricultural costs resulting from the proposed numeric nutrient
criteria may be estimated at $0.3--$0.7 million per year.

[[Page 74974]]

Table VI(C)(2)--Potential Incremental Agricultural BMP Costs
----------------------------------------------------------------------------------------------------------------
``Owner implemented BMP Total ``Owner
Area potentially Program'' plus Implemented BMP
Agricultural category needing controls ''Typical BMP Program'' Program'' and ''Typical
(acres) \a\ Unit Costs (2010$/ac/ BMP Program'' costs
yr) \b\ (2010$/yr)
----------------------------------------------------------------------------------------------------------------
Animal Feeding....................... 20-39 $18.56 $400-$700
Citrus............................... 0 156.80 $0
Fruit Orchards \c\................... 0-7 156.80 $0-$1,100
Cow Calf Production, Improved 1,115-4,568 15.84 $17,700-$72,400
Pastures............................
Cow Calf Production, Rangeland and 1,145-1,995 4.22 $4,800-$8,400
Wooded Pasture......................
Cow Calf Production, Unimproved 299-1,346 4.22 $1,300-$5,700
Pastures............................
Cropland and Pasture Land (general) 10,195-18,467 27.26 $277,900-$503,300
\d\.................................
Dairies.............................. 0 334.40 $0
Field Crop (Hayland) Production...... 479-1,397 18.56 $8,900-$25,900
Horse Farms.......................... 34-123 15.84 $500-$1,900
Ornamental Nursery................... 4-8 70.00 $300-$600
Floriculture \e\..................... 0 70.00 $0
Row Crop............................. 228-246 70.40 $16,100-$17,300
Sod/Turf Grass....................... 0 35.20 $0
Other Areas \f\...................... 565-1,069 18.56 $10,500-$19,800
--------------------------------------------------------------------------
Total \g\........................ 14,085-29,265 ....................... $338,300-$657,200
----------------------------------------------------------------------------------------------------------------
Note: Detail may not add to total due to independent rounding.
\a.\ Low end of range represents acres associated with impaired assessed waters assuming none of the unassessed
waters would be impaired under the proposed rule; high end of range represent low end plus controls on the
watersheds associated with impaired unassessed waters (estimated based on proportional impairment to assessed
waters) for which EPA has not already identified a need for controls for baseline or impaired assessed waters.
Based on GIS analysis of land use data from five water management districts (for entire State)
\b.\ Cost estimates from SWET (2008); representative of 2010 prices (personal communication with D. Bottcher,
2010).
\c.\ Owner/typical BMP unit costs based on costs for citrus crops.
\d.\ Owner/typical BMP unit costs based on average costs for improved pastures, unimproved/wooded pasture, row
crops, and field crops.
\e.\ Owner/typical BMP unit costs based on costs for ornamental nurseries.
\f.\ Includes FLUCCS Level 3 codes 2230, 2400, 2410, and 2540.
\g.\ Excludes land not in production.

3. Septic System Costs
Some nutrient reductions from septic systems may be necessary for
incrementally impaired waters to meet the numeric nutrient criteria in
this proposed rule. Several nutrient-related TMDLs in Florida identify
septic systems as a significant source of nitrogen and phosphorus
pollution. Some of the ways to address pollution from septic systems
may include greater use of inspection programs and repair of failing
systems, upgrading existing systems to advanced nutrient removal,
installation of decentralized cluster systems where responsible
management entities would ensure reliable operation and maintenance,
and connecting households and businesses to wastewater treatment
plants. Because of the cost, time, and issues associated with new
wastewater treatment plant construction, EPA assumed that the most
likely strategy to reduce nutrient loads from septic systems would be
to upgrade existing conventional septic systems to advanced nutrient
removal systems.
Septic systems in close proximity to surface waters are more likely
to contribute nutrient loads to waters than distant septic systems.
Florida Administrative Code provides that in most cases septic systems
should be at least 75 feet from surface waters (F.A.C. 64e-6.005(3)).
In addition, many of Florida's existing nutrient-related TMDLs identify
nearby failing septic systems as contributing to nutrient impairments
in surface waters.
For this economic analysis, EPA assumed that some septic systems
located near incrementally impaired waters may be required to upgrade
to advance nutrient removal systems. However, the distance that septic
systems can be safely located relative to these surface waters depends
on a variety of site-specific factors. Because of this uncertainty, EPA
assumed that septic systems located within 500 feet of any water (based
on land use types) in watersheds containing or, in the case of coastal
waters, surrounding incrementally impaired estuaries, coastal waters or
south Florida inland flowing waters may need to be upgraded from
conventional to advanced nutrient removal systems. The NRC agreed with
the 500-ft threshold, but found that the exclusion of septic systems in
springsheds is a deficiency of EPA's analysis. This proposed rule does
not include criteria for springsheds.
EPA used GIS analysis of data obtained from the Florida Department
of Health \222\ that provides the location of active septic systems in
the State to identify the potentially affected septic systems. This
analysis yielded 5,952 to 10,784 active septic systems that may be
affected by the proposed rule.
---------------------------------------------------------------------------

\222\ FDOH. 2010. Bureau of Onsite Sewage GIS Data Files.
Florida Department of Health, Division of Environmental Health.
http://www.doh.state.fl.us/Environment/programs/EhGis/EhGisDownload.htm.
---------------------------------------------------------------------------

EPA evaluated the cost of upgrading existing septic systems to
advanced nutrient removal systems. The NRC also recommended that EPA
consider permeable reactive barriers (PRB) in their technology costs
and take into account any additional Florida-specific costs related to
septic system upgrades (e.g., performance-based treatment systems,
under Florida regulations, need to be designed by Florida licensed
professional engineers). EPA included this technology in the cost
analysis, resulting in the range of upgrade capital costs from $3,300
to $8,800 per system. See the Economic Analysis for further detail. For
O&M costs, EPA relied on a study that compared the annual costs
associated with various septic system treatment technologies including
conventional onsite sewage treatment and disposal system and fixed film
activated sludge systems. Based on this study, EPA estimated the
incremental

[[Page 74975]]

O&M costs for an advanced system to be $650 per year.\223\ In addition,
homeowners would also incur a biennial permit fee of $100 (or $50 per
year) for the upgraded system. Thus, based on annual O&M costs of $700
and annualizing capital costs at 7% over 20 years, total annual costs
could range from approximately $1,000 to $1,500 for each upgrade. EPA
estimated the total annual costs of upgrading septic systems by
multiplying this range of unit costs with the number of systems
identified for upgrade. Using this method, total annual costs for
upgrading septic systems in incrementally impaired watersheds could
range from $6.0 million to $16.2 million.
---------------------------------------------------------------------------

\223\ Chang, N., M. Wanielista, A. Daranpob, F. Hossain, Z.
Xuan, J. Miao, S. Liu, Z. Marimon, and S. Debusk. 2010. Onsite
Sewage Treatment and Disposal Systems Evaluation for Nutrient
Removal. FDEP Project WM 928. Report Submitted to Florida
Department of Environmental Protection, by Stormwater Management
Academy, Civil, Environmental, and Construction Engineering
Department, University of Central Florida.
---------------------------------------------------------------------------

D. Governmental Costs
The proposed rule may result in the identification of incrementally
impaired waters that would require the development of additional TMDLs.
As the principal State regulatory agency implementing water quality
standard, FDEP may incur costs associated with developing additional
TMDLs. EPA's analysis identified 95 (based on the analysis of assessed
waters) to 183 (including potentially impaired unassessed waters)
incrementally impaired waters (WBIDs).
Because current TMDLs for estuaries and coastal waters in Florida
include an average of approximately four WBIDs each, EPA estimates that
the State of Florida may need to develop and adopt approximately 24 to
46 additional TMDLs. The NRC recommended applying Florida-specific TMDL
development costs from a FDEP report detailing FDEP TMDL program costs.
EPA used a range of costs from a 2001 EPA study that found the cost of
developing a TMDL at different levels of aggregation and the Florida-
specific TMDL cost estimates are within this range of
costs.^{224, 225} For this analysis, EPA used the estimates for
a single cause of impairment and adjusted the costs to account for the
possibility that a TMDL may need to address more than one pollutant
(because most of the incrementally impaired waters in EPA's analysis
exceeded the criteria for more than one pollutant). Under this
assumption, EPA estimated the average TMDL cost to be approximately
$47,000 ($28,000 on average for one pollutant, plus $6,000 on average
for the other pollutant and adjusted to 2010 dollars). EPA also
estimated unit costs based on the high end of typical TMDL development
costs, plus an additional $6,000 for the second nutrient. Escalating to
2010 dollars, the high range of TMDL development cost of $212,000. For
24 to 46 TMDLs, total costs for incremental TMDL development could be
$1.1 million to $10.2 million.
---------------------------------------------------------------------------

\224\ USEPA. 2001. The National Costs of the Total Maximum Daily
Load Program (Draft Report). EPA-841-D-01-003. U.S. Environmental
Protection Agency, Office of Water, Washington DC.
\225\ EPA did not adjust these estimates to account for
potential reductions in resources required to develop TMDLs given
that scientifically based numeric targets were developed as part of
this proposed rule. Costs for these TMDLs are thus likely to be an
overestimate.
---------------------------------------------------------------------------

FDEP currently operates its TMDL schedule on a five-phase cycle
that rotates through Florida's five basins over five years. Under this
schedule, completion of TMDLs for high priority waters will take 9
years; it will take an additional 5 years to complete the process for
medium priority waters. Assuming all the incremental impairments are
high priority and FDEP develops the new TMDLs over a 9-year period,
annual costs could be $0.1 to $1.1 million.
Should the State of Florida submit current TMDL targets as Federal
site specific alternative criteria (SSAC) for EPA review and approval,
EPA believes it is reasonable to assume that information used in the
development of the TMDLs will substantially reduce the time and effort
needed to provide a scientifically defensible justification for such
applications. If EPA's assumption is incorrect and there were to be
increased costs for the SSAC process, EPA expects that such cost
underestimation would be cancelled out by continuing to include the
costs of developing the scientifically based numeric targets for new
TMDLs. Thus, EPA did not separately analyze any incremental costs
associated with SSAC.
Similarly, state and local agencies regularly monitor TN and TP in
ambient waters. These data are the basis for the extensive IWR database
maintained by the State of Florida. Because Florida is currently
monitoring TN, TP, and chlorophyll-a concentrations in many waters, EPA
assumed that the rule is unlikely to have a significant impact on costs
related to water quality monitoring activities.
E. DPVs
EPA is proposing several options for DPVs. For this analysis, EPA
assumed that the DPVs equal the numeric nutrient criteria for the
segment to which the stream discharges. If the State of Florida were to
choose any of the other three proposed options for DPVs, then these
costs may be over- or underestimated. To estimate whether the DPVs are
being met, EPA used the same minimum data requirements (e.g., four data
points in one year with at least one data point each in summer and
winter seasons) and attainment criteria (no more than one exceedance in
a three-year period) for evaluating the criteria. EPA used data from
estuary pour points from any station within 500 feet of and within the
same WBID as the pour point. For south Florida pour points EPA did not
use the data from the technical report, but used all data from the WBID
in which the pour point is located to assess impairment.
For this analysis, EPA assumed that any WBID containing a pour
point exceeding the criteria would be designated as impaired. EPA then
identified the watersheds that contain or surround, in the case of
coastal waters, those incrementally impaired WBIDs. See Appendix G of
the economic analysis for more information.

Table VI(E). Summary of Potential Incremental Costs Associated with DPVs
------------------------------------------------------------------------
Total
potential
Source category incremental
annual cost
($/year)
------------------------------------------------------------------------
Municipal Wastewater.................................... $29.4-$29.6
Industrial Dischargers.................................. $0.0
Urban Stormwater........................................ $9.5-$185.1
Agriculture............................................. $0.5-$0.9
Septic Systems.......................................... $2.0-$3.0
Government/Program Implementation \1\................... $0.0-$0.1
---------------
Total............................................... $41.4-$218.6
------------------------------------------------------------------------
\1.\ Assuming 3 TMDLs for 13 WBIDs (approximately 4 WBIDs per TMDL) over
a 9-year period.

F. Summary of Costs
Table VI(F) summarizes EPA's estimates of potential incremental
costs associated with additional State and private sector activities to
meet the numeric criteria supporting State designated uses. Note, these
total costs include costs associated with unassessed waters. Because of
uncertainties in the pollution controls ultimately implemented by the
State of Florida, actual costs may vary depending on the site-specific
source reductions needed to meet the new numeric criteria.

[[Page 74976]]

Table VI(F)--Summary of Potential Annual Costs \1\ (2010 dollars)
------------------------------------------------------------------------
Annual Cost
Sector (millions) \2\
------------------------------------------------------------------------
Municipal Wastewater................................... $44.1-$49.7
Industrial Dischargers................................. $15.2
Urban Stormwater....................................... $131.9-$330.9
Agriculture............................................ $0.3-$0.7
Septic Systems......................................... $6.0-$16.2
Government/Program Implementation (TMDLs).............. $0.1-$1.1
Downstream Protection Values........................... $41.4-$218.6
----------------
Total.............................................. $239.0--$632.4
------------------------------------------------------------------------
\1.\ Includes costs for assessed, unassessed, and DPVs.
\2.\ Low end of range represents estimated costs under the assumption
that none of the unassessed waters would be impaired under the
proposed rule; high end of range represents costs associated with the
assumption of proportional impairment of unassessed waters.

EPA also calculated the potential costs to Florida households.
Given the uncertainty regarding the magnitude of the estimated costs
ultimately borne by households, EPA sought to minimize that uncertainty
with a selective though matched set of potential costs and potentially
affected households. Although GIS analysis could be used to overlay
maps of affected populations and facilities with incrementally impaired
watersheds, a simpler more direct approach is to assume that all
households in Florida are either served by a wastewater treatment plant
or septic system, and pay taxes that would support implementation
programs conducted by the State. In addition, because the sector with
the largest costs is urban stormwater, EPA decided to include this
sector as well. Thus, EPA decided to look at the total costs of the two
rules across all households in Florida. Also, given the cost-pass-
through of agriculture costs and industrial costs to consumers outside
the State of Florida, EPA did not consider them for the estimate of
average costs per households in Florida. Therefore, EPA also calculated
the total costs for municipal wastewater and stormwater controls,
septic upgrades, and government/program implementation costs for both
the proposed rule and the Inland rule and compared this sum to the
total number of households in the State. This may underestimate actual
household costs if some costs are not borne equally by households
statewide, but instead are concentrated within the watersheds for which
controls are needed. EPA's total estimated annual cost for compliance
with this proposed rule, and the Inland rule, represents $44 to $108
per household per year for both rules across all households in Florida.
This equals $3.60 to $9 per month per household in Florida. Please
refer to Section 13 in the Economic Analysis for more information.
EPA also considered whether the potential costs of this proposed
rule could result in employment impacts. Environmental regulations can
both increase and decrease employment, and whether the net effect is
positive or negative depends on many factors. See Chapter 13 of the
Economic Analysis for further discussion.
G. Benefits
Since elevated concentrations of nutrients in surface waters can
result in adverse ecological effects, human health impacts, and
negative economic impacts, EPA expects the proposed numeric nutrient
criteria to result in significant ecological, human health, and
economic benefits to Florida. For example, excess nutrients in water
can cause eutrophication, which can lead to harmful (sometimes toxic)
algal blooms, loss of rooted plants, and decreased dissolved oxygen. In
turn, these results can lead to adverse impacts on aquatic life,
fishing, swimming, wildlife watching, camping, and drinking water.
Excess nutrients can also cause: nuisance surface scum, reduced food
for herbivorous wildlife, fish kills, alterations in fish communities,
and unsightly shorelines that can decrease property values. Excessive
nutrient loads can also lead to harmful algal blooms (HABs), which can
cause a range of adverse human health effects including dermal,
gastrointestinal, neurological, and respiratory problems, and in severe
cases, may even result in fatalities.
Nutrient impairment is currently a major concern for many bays,
estuaries, and coasts within the United States, and is particularly
severe for many Florida waters. FDEP's 2010 report identifies
approximately 569 square miles (364,160 acres) of estuaries (about 23
percent of assessed estuarine area) and 102 square miles (65,280 acres)
of coastal waters (about 1.5 percent of assessed coastal waters) as
impaired by nutrients. These impairments may have a significant impact
on the value of environmental goods and services provided by the
affected waterbodies. For example, the losses of submerged aquatic
vegetation resulting from eutrophication can have significant economic
impacts. In 2009, Florida seagrass communities supported an estimated
harvest of $23 million for just six species of commercial fish and
shellfish.\226\
---------------------------------------------------------------------------

\226\ Crist, C. 2010. Seagrass Awareness Month. Proclamation by
the Governor Charlie Crist of the State of Florida. Florida
Department of Environmental Protection.
---------------------------------------------------------------------------

In Florida's environment and economy, the tourism-focused goods and
services provided by its bays, estuaries, and coastal waters are
particularly valuable. The tourism industry of Florida's nearshore
counties contributes approximately $12.4 billion (2004 dollars) to the
State's economy annually.\227\ Coral reefs are especially important
contributors to Florida's tourism sector. Reef-related recreational
expenditures on activities such as snorkeling, scuba diving, fishing,
and glass bottom boating in four counties in southeastern Florida for a
one year period in 2000-2001 totaled $5.4 billion.\228\
---------------------------------------------------------------------------

\227\ NOEP. 2006. Coastal Economy Data. National Ocean Economics
Program. www.oceaneconomics.org/Market/coastal/coastalEcon.asp.
\228\ Johns, G.M., V.R. Leeworthy, F.W. Bell, and M.A. Bonn.
2001. Socioeconomic Study of Reefs in SoutheastFlorida. Final Report
prepared by Hazen and Sawyer, Hollywood, FL, for Broward County,
Palm Beach County, Miami-Dade County, Monroe County, Florida Fish
and Wildlife Conservation Commission, and National Oceanic and
Atmospheric Administration.
---------------------------------------------------------------------------

The proposed rule will help reduce nitrogen and phosphorus
concentrations in Florida's estuaries, coastal waters and south Florida
inland flowing waters. In turn, this reduction will improve ecological
function and prevent further degradation that can result in substantial
economic benefits to Florida citizens. EPA's economic analysis document
describes in detail many of the potential benefits associated with
meeting the numeric criteria in the proposed rule for nitrogen and
phosphorus, including reduced human health risks, ecological benefits
and functions, improved recreational opportunities, aesthetic
enhancements and others.
1. Monetized Benefits Estimates
Reducing nutrient concentrations will increase services provided by
water resources to recreational users. For example, some coastal waters
that are not usable for recreation may become available following
implementation of the rule, thereby expanding recreation options for
residential users and tourists. Other waters that are available for
recreation can become more attractive for users by making recreational
trips more enjoyable. Individuals may also take trips more frequently
if they enjoy their recreational activities more. In addition to
recreational improvements, the

[[Page 74977]]

proposed rule is expected to generate nonuse benefits from bequest,
altruism, and existence motivations. Individuals may value the
knowledge that water quality is being maintained, ecosystems are being
protected, and populations of individual species are healthy,
independently from any use value.
EPA used a benefits transfer function based on meta-analysis of
surface water valuation studies to estimate both use and nonuse
benefits from improvements in surface water. This approach is based on
the method used to quantify nonmarket benefits in the 2009
Environmental Impact and Benefits Assessment for Final Effluent
Guidelines and Standards for the Construction and Development Category
(EPA, 2009), also used in the economic analysis of the Inland Rule. The
approach quantifies benefits based on reach-specific baseline water
quality and the estimated change in pollutant concentrations. The
approach translates reductions in nutrients into an indicator of
overall water quality (via a ``water quality ladder,'' or WQL) and
values these improvements in terms of household willingness to pay
(WTP) for the types of uses (e.g., as fishing and swimming) that are
supported by different water quality levels.
EPA calculated the baseline WQL scores for incrementally affected
waters by comparing the water quality observations to criteria. For
coastal waters, only Chl-a criteria are applicable, and for these
waters, EPA estimated baseline WQL scores based on Chl-a exceedances
only. For other marine waters, EPA developed estimates of baseline
water quality based on comparing the water quality observations to the
applicable criteria in the following order: (1) Exceedances of proposed
TN criteria; (2) exceedances of proposed TP criteria; and (3)
exceedances of proposed Chl-a criteria. The baseline WQL score is based
on the percent exceedance of the applicable criterion value. EPA
assumes all incrementally impaired waters will meet the proposed
criteria and estimated the potential changes for each waterbody. EPA
estimated that up to 163 unassessed WBIDs may be incrementally
impaired, but water quality data for these waters are not available. To
estimate the potential benefits associated with these potentially
impaired unassessed waters, EPA estimated the same percent exceedance
of the potentially impaired assessed waters. Because EPA's estimates of
monetized benefits only reflect the water quality improvements for
WBIDs, and not HUC-12s, these potential benefits are underestimated and
should not be directly compared to costs, which include HUC-12 costs.
EPA then estimated monetized benefit values of these water quality
improvements using benefits transfer based on a meta-regression of 45
studies that value water quality improvements in surface waters. Using
the meta-analysis EPA estimated a household WTP function with
independent variables that characterize (1) the underlying study and
methodology used, (2) demographic and other characteristics of the
surveyed populations, (3) geographic region and scale, and (4) resource
characteristics and improvements. More details on the meta-analysis can
be found in the Economic Analysis.
Using this function, EPA derived household WTP estimates for both
full time and part time residents of the State. EPA estimated that
seasonal residents live in the State for approximately four months of
the year; therefore EPA weighted household WTP values for seasonal
residents by one third. EPA then weighted household WTP estimates by
the percentage of State water miles that are expected to improve. EPA
estimated total benefits by multiplying the weighted household WTP
value with the total number of benefiting households. EPA estimated the
number of full time residents by dividing the total State population by
average household size for the State as provided by the U.S. Census
Bureau's 2010 American Community Survey (U.S. Census Bureau, 2010). The
number of part-time households in Florida is based on Smith and House
(2006), who used survey data to estimate the number, timing, and
duration of temporary moves to Florida at peak seasons. EPA used the
Smith and House (2006) results and U.S. Census Bureau (2010) statistics
on household size to estimate the number of part-time households in
Florida. Total monetized benefits, including monetized benefits of
unassessed waters, may be in the range from $39.0 million to $53.4
million annually, as shown in Table VI(F). The range reflects EPA's
assumptions regarding the location of unassessed waters that might be
incrementally impaired.
Because EPA's estimates of monetized benefits only reflect use and
nonuse values associated with water quality improvements to Florida
residents (full and part time), these potential benefits are likely
underestimated compared to costs. The population considered in the
benefits analysis of the rule does not include households outside of
Florida that may also hold values for water resources in the State of
Florida. Even if per household values for out-of-State residents are
small, they may be significant in the aggregate if these values are
held by a substantial number of out-of-State households. EPA notes that
four times as many out-of-State and foreign tourists visit the State's
saltwater beaches each year as State residents do. Not including out-
of-State residents in the analysis is likely to result in an
underestimation of the total benefits of improved water quality.
Although these monetized benefits estimates do not account for all
potential economic benefits arising from the proposed rule, they help
to demonstrate the economic importance of restoring and protecting
Florida waters from the impacts of nitrogen and phosphorus pollution.

Table VI(F)--Potential Annual State Benefits Associated With the
Proposed Criteria Including Unassessed Waters (2010 dollars)
------------------------------------------------------------------------
Average benefit Total benefits
WTP estimate per mile \1\ (millions) \2\
------------------------------------------------------------------------
Lower 5% Bound.................... $8,200 $17.2-$23.6
Mean.............................. 18,500 $39.0-$53.4
Upper 95% Bound................... 34,500 $72.5-$99.4
------------------------------------------------------------------------
\1\ Total benefits divided by 2,102 incrementally impaired assessed
miles.
\2\ Benefits per mile times the number of incrementally impaired miles;
based on between 2,102 and 2,882 potentially improved miles. The low
end of the range represents assessed waters only, and the high end of
the range includes unassessed waters.

[[Page 74978]]

VII. Statutory and Executive Order Reviews

A. Executive Orders 12866 (Regulatory Planning and Review) and 13563
(Improving Regulation and Regulatory Review)

Under Executive Order 12866 (58 FR 51735, October 4, 1993), this
action is a ``significant regulatory action.'' Accordingly, EPA
submitted this action to the Office of Management and Budget (OMB) for
review under Executive Orders 12866 and 13563 (76 FR 3821, January 21,
2011) and any changes made in response to OMB recommendations have been
documented in the docket for this action. This proposed rule does not
establish any requirements directly applicable to regulated entities or
other sources of nitrogen and phosphorus pollution. Moreover, existing
narrative water quality criteria in State law already require that
nutrients not be present in waters in concentrations that cause an
imbalance in natural populations of flora and fauna in estuaries and
coastal waters in Florida and in south Florida inland flowing waters.

B. Paperwork Reduction Act

This action does not impose any direct new information collection
burden under the provisions of the Paperwork Reduction Act, 44 U.S.C.
3501 et seq. Actions to implement these standards may entail additional
paperwork burden. Burden is defined at 5 CFR 1320.3(b). This action
does not include any information collection, reporting, or record-
keeping requirements.

C. Regulatory Flexibility Act

The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedure Act or any other statute unless the agency certifies that the
rule will not have significant economic impact on a substantial number
of small entities. Small entities include small businesses, small
organizations, and small governmental jurisdictions.
For purposes of assessing the impacts of this action on small
entities, small entity is defined as: (1) A small business as defined
by the Small Business Administration's (SBA) regulations at 13 CFR
121.201; (2) a small governmental jurisdiction that is a government of
a city, county, town, school district or special district with a
population of less than 50,000; and (3) a small organization that is
any not-for-profit enterprise that is independently owned and operated
and is not dominant in its field.
Under the CWA water quality standards program, states must adopt
water quality standards for their waters and must submit those water
quality standards to EPA for review and approval or disapproval; if the
Agency disapproves a state standard and the state does not adopt
appropriate revisions to address EPA's disapproval, EPA must promulgate
standards consistent with the statutory and regulatory requirements.
EPA also has the authority to promulgate water quality standards in any
case where the Administrator determines that a new or revised standard
is necessary to meet the requirements of the CWA. State standards
approved by EPA (or EPA-promulgated standards) are implemented through
various water quality control programs including the NPDES program,
which limits discharges to navigable waters except in compliance with
an NPDES permit. The CWA requires that all NPDES permits include any
limits on discharges that are necessary to meet applicable water
quality standards.
Thus, under the CWA, EPA's promulgation of water quality standards
establishes standards that the State of Florida implements through the
NPDES permit process. The State has discretion in developing discharge
limits, as needed to meet the standards. This proposed rule does not
itself establish any requirements that are applicable to small
entities. As a result of this action, the State of Florida will need to
ensure that permits it issues include any limitations on discharges
necessary to comply with the standards established in the final rule.
In doing so, the State will have a number of choices associated with
permit writing (e.g., relating to compliance schedules, variances,
etc.). While Florida's implementation of the rule may ultimately result
in new or revised permit conditions for some dischargers, including
small entities, EPA's action, by itself, does not impose any of these
requirements on small entities; that is, these requirements are not
self-implementing. Thus, I certify that this rule will not have a
significant economic impact on a substantial number of small entities.

D. Unfunded Mandates Reform Act

Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public
Law 104-4, establishes requirements for Federal agencies to assess the
effects of their regulatory actions on state, local, and tribal
governments and the private sector. Under section 202 of the UMRA, EPA
generally must prepare a written statement, including a cost-benefit
analysis, for proposed and final rules that include a ''Federal
mandate'' that may result in expenditures to state, local, and Tribal
governments, in the aggregate, or to the private sector, of $100
million or more in any one year. A ``Federal mandate,'' is any
provision in federal statute or regulation that would impose an
enforceable duty on State, local or Tribal governments or the private
sector.\229\ Before promulgating an EPA rule for which a written
statement is needed under section 202, section 205 of the UMRA
generally requires EPA to identify and consider a reasonable number of
regulatory alternatives and adopt the least costly, most cost-effective
or least burdensome alternative that achieves the objectives of the
rule. The provisions of section 205(a) do not apply when they are
inconsistent with law. Moreover, section 205(b) allows EPA to adopt an
alternative other than the least costly, most cost-effective or least
burdensome alternative if the Administrator publishes with the final
rule an explanation of why that alternative was not adopted. Before EPA
establishes any regulatory requirements that may significantly or
uniquely affect small governments, including Tribal governments, it
must have developed under section 203 of the UMRA a small government
agency plan. The plan must provide for notifying potentially affected
small governments, enabling officials of affected small governments to
have meaningful and timely input in the development of EPA regulatory
proposals with significant Federal intergovernmental mandates, and
informing, educating, and advising small governments on compliance with
the regulatory requirements.
---------------------------------------------------------------------------

\229\ A ``Federal mandate'' does not include conditions of
Federal assistance and generally does not include duties arising
from participation in a voluntary Federal program.
---------------------------------------------------------------------------

This proposed rule contains no Federal mandates (under the
regulatory provisions of Title II of the UMRA) for state, local, or
Tribal governments or the private sector. As these water quality
criteria are not self-implementing, EPA's proposed rule does not
regulate or affect any entity. Because this proposed rule does not
regulate or affect any entity, it therefore is not subject to the
requirements of sections 202 and 205 of UMRA.
EPA determined that this proposed rule contains no regulatory
requirements that might significantly or uniquely affect small
governments.

[[Page 74979]]

Moreover, water quality standards, including those promulgated here,
apply broadly to dischargers and are not uniquely applicable to small
governments. Thus, this proposed rule is not subject to the
requirements of section 203 of UMRA.

E. Executive Order 13132 (Federalism)

This action does not have federalism implications. It will not have
substantial direct effects on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government, as
specified in Executive Order 13132. EPA's authority and responsibility
to promulgate Federal water quality standards when state standards do
not meet the requirements of the CWA is well established and has been
used on various occasions in the past. The proposed rule would not
substantially affect the relationship between EPA and the States and
Territories, or the distribution of power or responsibilities between
EPA and the various levels of government. The proposed rule would not
alter Florida's considerable discretion in implementing these water
quality standards. Further, this proposed rule would not preclude
Florida from adopting water quality standards that EPA concludes meet
the requirements of the CWA, either before or after promulgation of the
final rule, which would eliminate the need for Federal standards. Thus,
Executive Order 13132 does not apply to this proposed rule.
Although section 6 of Executive Order 13132 does not apply to this
action, EPA communicated with the State of Florida to discuss the
Federal rulemaking process. In the spirit of Executive Order 13132, and
consistent with EPA policy to promote communications between EPA and
State and local governments, EPA specifically solicits comment on this
proposed rule from State and local officials.

F. Executive Order 13175 (Consultation and Coordination With Indian
Tribal Governments)

Subject to the Executive Order 13175 (65 FR 67249, November 9,
2000) EPA may not issue a regulation that has tribal implications, that
imposes substantial direct compliance costs, and that is not required
by statute, unless the Federal government provides the funds necessary
to pay the direct compliance costs incurred by Tribal governments, or
EPA consults with tribal officials early in the process of developing
the proposed regulation and develops a tribal summary impact statement.
EPA has concluded that this action may have tribal implications.
However, the rule will neither impose substantial direct compliance
costs on tribal governments, nor preempt Tribal law.
In the State of Florida, there are two Indian tribes, the Seminole
Tribe of Florida and the Miccosukee Tribe of Indians of Florida, with
flowing waters. Both tribes have been approved for treatment in the
same manner as a state (TAS) status for CWA sections 303 and 401 and
have federally-approved water quality standards in their respective
jurisdictions. These tribes are not subject to this proposed rule.
However, this rule may impact the tribes because the numeric criteria
for Florida will apply to waters adjacent to the tribal waters.
EPA consulted with Tribal officials early in the process of
developing this regulation to permit them to have meaningful and timely
input into its development. At a consultation teleconference held on
March 1, 2012, EPA summarized the available information regarding this
proposed rule, and requested comments on the proposal and its possible
effects on tribal waters. Information relevant to this proposed action
and the related Tribal consultation is posted on the EPA Tribal Portal
site at http://www.epa.gov/tribal/consultation/index.htm. EPA
specifically solicits additional comment on this proposed rule from
tribal officials.

G. Executive Order 13045 (Protection of Children From Environmental
Health and Safety Risks)

This action is not subject to EO 13045 (62 FR 19885, April 23,
1997) because it is not economically significant as defined in EO
12866, and because the Agency believes that this rule will result in
the reduction of environmental health and safety risks that could
present a disproportionate risk to children.

H. Executive Order 13211 (Actions That Significantly Affect Energy
Supply, Distribution, or Use)

This rule is not a ``significant energy action'' as defined in
Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use'' (66 FR 28355
(May 22, 2001)), because it is not likely to have a significant adverse
effect on the supply, distribution, or use of energy.

I. National Technology Transfer Advancement Act of 1995

Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (``NTTAA''), Public Law 104-113, section 12(d) (15 U.S.C.
272 note) directs EPA to use voluntary consensus standards in its
regulatory activities unless to do so would be inconsistent with
applicable law or otherwise impractical. Voluntary consensus standards
are technical standards (e.g., materials specifications, test methods,
sampling procedures, and business practices) that are developed or
adopted by voluntary consensus standards bodies. The NTTAA directs EPA
to provide Congress, through OMB, explanations when the Agency decides
not to use available and applicable voluntary consensus standards.
This proposed rulemaking does not involve technical standards.
Therefore, EPA is not considering the use of any voluntary consensus
standards.

J. Executive Order 12898 (Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations)

Executive Order (EO) 12898 (Feb. 16, 1994) establishes Federal
executive policy on environmental justice. Its main provision directs
Federal agencies, to the greatest extent practicable and permitted by
law, to make environmental justice part of their mission by identifying
and addressing, as appropriate, disproportionately high and adverse
human health or environmental effects of their programs, policies, and
activities on minority populations and low-income populations in the
United States.
EPA has determined that this proposed rule does not have
disproportionately high and adverse human health or environmental
effects on minority or low-income populations because it would afford a
greater level of protection to both human health and the environment if
these numeric nutrient criteria are promulgated for Class I, Class II
and Class III waters in the State of Florida.

List of Subjects in 40 CFR Part 131

Environmental protection, Water quality standards, Nitrogen and
phosphorus pollution, Nutrients, Florida.

Dated: November 30, 2012.
Lisa P. Jackson,
Administrator.
For the reasons set out in the preamble, EPA proposes to amend 40
CFR part 131 as follows:

PART 131--WATER QUALITY STANDARDS

1. The authority citation for part 131 continues to read as
follows:

[[Page 74980]]

Authority: 33 U.S.C. 1251 et seq.

Subpart D--[Amended]

2. Section 131.45 is added to read as follows:

Sec. 131.45 Water Quality Standards for the State of Florida's
Estuaries, Coastal Waters, and South Florida Inland Flowing Waters

(a) Scope. This section promulgates numeric criteria for nitrogen
and phosphorus pollution for Class I, Class II, and Class III waters in
the State of Florida. This section also contains provisions for site-
specific alternative criteria.
(b) Definitions.--(1) Canal means a trench, the bottom of which is
normally covered by water with the upper edges of its two sides
normally above water.
(2) Coastal water means all marine waters that have been classified
as Class II (Shellfish Propagation or Harvesting) or Class III
(Recreation, Propagation and Maintenance of a Healthy, Well-Balanced
Population of Fish and Wildlife) water bodies pursuant to Section 62-
302.400, F.A.C., extending to three nautical miles from shore that are
not classified as estuaries.
(3) Estuary means predominantly marine regions of interaction
between rivers and nearshore ocean waters, where tidal action and river
flow mix fresh and salt water. Such areas include bays, mouths of
rivers, and lagoons that have been classified as Class II (Shellfish
Propagation or Harvesting) or Class III (Recreation, Propagation and
Maintenance of a Healthy, Well-Balanced Population of Fish and
Wildlife) water bodies pursuant to Section 62-302.400, F.A.C.,
excluding wetlands.
(4) Everglades Agricultural Area (EAA) means those lands described
in Florida Statute Section 373.4592 (1994) subsection (15).
(5) Everglades Protection Area (EvPA) means Water Conservation
Areas 1 (which includes the Arthur R. Marshall Loxahatchee National
Wildlife Refuge), 2A, 2B, 3A, and 3B, and the Everglades National Park.
(6) Inland flowing waters means inland predominantly fresh surface
water streams that have been classified as Class I (Potable Water
Supplies) or Class III (Recreation, Propagation and Maintenance of a
Healthy, Well-Balanced Population of Fish and Wildlife) water bodies
pursuant to Section 62-302.400, F.A.C., excluding wetlands (e.g.,
sloughs).
(7) Marine Lake means a slow-moving or standing body of marine
water that occupies an inland basin that is not a stream, spring, or
wetland.
(8) Predominantly fresh waters means surface waters in which the
chloride concentration at the surface is less than 1,500 milligrams per
liter.
(9) Predominantly marine waters means surface waters in which the
chloride concentration at the surface is greater than or equal to 1,500
milligrams per liter.
(10) South Florida inland flowing waters means inland flowing
waters in the South Florida Nutrient Watershed Region, which
encompasses the waters south of Lake Okeechobee, the Caloosahatchee
River (including Estero Bay) watershed, and the St. Lucie watershed.
(11) State means the State of Florida, whose transactions with the
U.S. EPA in matters related to 40 CFR 131.45 are administered by the
Secretary, or officials delegated such responsibility, of the Florida
Department of Environmental Protection (FDEP), or successor agencies.
(12) Stream means a free-flowing, predominantly fresh surface water
in a defined channel, and includes rivers, creeks, branches, canals,
freshwater sloughs, and other similar water bodies.
(13) Surface water means water upon the surface of the earth,
whether contained in bounds created naturally or artificially or
diffused. Water from natural springs shall be classified as surface
water when it exits from the spring onto the Earth's surface.
(14) Tidal creek means a relatively small coastal tributary with
variable salinity that lies at the transition zone between terrestrial
uplands and the open estuary.
(c) Criteria for Florida Waters.
(1) Criteria for Estuaries.
The applicable total nitrogen (TN), total phosphorus (TP), and
chlorophyll a criteria for estuaries are shown in Table 1.

Table 1--EPA's Numeric Criteria for Florida's Estuaries
[In geographic order Northwest to Northeast]
----------------------------------------------------------------------------------------------------------------
Proposed Criteria
-----------------------------------------------
Segment Segment ID Chl-a* ([mu]g/
TN* (mg/L) TP* (mg/L) L)
----------------------------------------------------------------------------------------------------------------
Perdido Bay:
Upper Perdido Bay........................... 0101 0.59 0.042 5.2
Big Lagoon.................................. 0102 0.26 0.019 4.9
Central Perdido Bay......................... 0103 0.47 0.031 5.8
Lower Perdido Bay........................... 0104 0.34 0.023 5.8
Pensacola Bay:
Blackwater Bay.............................. 0201 0.53 0.022 3.9
Upper Escambia Bay.......................... 0202 0.43 0.025 3.7
East Bay.................................... 0203 0.50 0.021 4.2
Santa Rosa Sound............................ 0204 0.34 0.018 4.1
Lower Escambia Bay.......................... 0205 0.44 0.023 4.0
Upper Pensacola Bay......................... 0206 0.40 0.021 3.9
Lower Pensacola Bay......................... 0207 0.34 0.020 3.6
Santa Rosa Sound............................ 0208 0.33 0.020 3.9
Santa Rosa Sound............................ 0209 0.36 0.020 4.9
Choctawhatchee Bay:
Eastern Choctawhatchee Bay.................. 0301 0.47 0.025 8.1
Central Choctawhatchee Bay.................. 0302 0.36 0.019 3.8
Western Choctawhatchee Bay.................. 0303 0.21 0.012 2.4
St. Andrews Bay:
East Bay.................................... 0401 0.31 0.014 4.6
St. Andrews Sound........................... 0402 0.14 0.009 2.3
Eastern St. Andrews Bay..................... 0403 0.24 0.021 3.9

[[Page 74981]]

Western St. Andrews Bay..................... 0404 0.19 0.016 3.1
Southern St. Andrews Bay.................... 0405 0.15 0.013 2.6
North Bay 1................................. 0406 0.22 0.012 3.7
North Bay 2................................. 0407 0.22 0.014 3.7
North Bay 3................................. 0408 0.21 0.016 3.4
West Bay.................................... 0409 0.23 0.022 3.8
St. Joseph Bay:
St. Joseph Bay.............................. 0501 0.25 0.018 3.8
Apalachicola Bay:
St. George Sound............................ 0601 0.53 0.019 3.6
Apalachicola Bay............................ 0602 0.51 0.019 2.7
East Bay.................................... 0603 0.76 0.034 1.7
St. Vincent Sound........................... 0605 0.52 0.016 11.9
Apalachicola Offshore....................... 0606 0.30 0.008 2.3
Alligator Harbor:
Alligator Harbor............................ 0701 0.36 0.011 2.8
Alligator Offshore.......................... 0702 0.33 0.009 3.1
Alligator Offshore.......................... 0703 0.33 0.009 2.9
Ochlockonee Bay \+\:
Ochlockonee-St. Marks Offshore.............. 0825 0.79 0.033 2.7
Ochlockonee Offshore........................ 0829 0.47 0.019 1.9
Ochlockonee Bay............................. 0830 0.66 0.037 1.8
St. Marks River Offshore.................... 0827 0.51 0.022 1.7
St. Marks River............................. 0828 0.55 0.030 1.2
Big Bend/Apalachee Bay \+\:
Econfina Offshore........................... 0824 0.59 0.028 4.6
Econfina.................................... 0832 0.55 0.032 4.4
Fenholloway................................. 0822 1.15 0.444 1.9
Fenholloway Offshore........................ 0823 0.48 0.034 10.3
Steinhatchee-Fenholloway Offshore........... 0821 0.40 0.023 4.1
Steinhatchee River.......................... 0819 0.67 0.077 1.0
Steinhatchee Offshore....................... 0820 0.34 0.018 3.5
Steinhatchee Offshore....................... 0818 0.39 0.032 4.8
Suwannee River \+\:
Suwannee Offshore........................... 0817 0.78 0.049 5.2
Springs Coast \+\:
Waccasassa River Offshore................... 0814 0.38 0.019 3.9
Cedar Keys.................................. 0815 0.32 0.019 4.1
Crystal River............................... 0812 0.35 0.013 1.3
Crystal-Homosassa Offshore.................. 0813 0.36 0.013 2.1
Homosassa River............................. 0833 0.47 0.032 1.9
Chassahowitzka River........................ 0810 0.32 0.010 0.7
Chassahowitzka River Offshore............... 0811 0.29 0.009 1.7
Weeki Wachee River.......................... 0808 0.32 0.010 1.6
Weeki Wachee Offshore....................... 0809 0.30 0.009 2.1
Pithlachascotee River....................... 0806 0.50 0.022 2.4
Pithlachascotee Offshore.................... 0807 0.32 0.011 2.5
Anclote River............................... 0804 0.48 0.037 4.7
Anclote Offshore............................ 0805 0.31 0.011 3.2
Anclote Offshore South...................... 0803 0.29 0.008 2.6
Lake Worth Lagoon/Loxahatchee:
North Lake Worth Lagoon..................... 1201 0.55 0.067 4.7
Central Lake Worth Lagoon................... 1202 0.57 0.089 5.3
South Lake Worth Lagoon..................... 1203 0.48 0.034 3.6
Lower Loxahatchee........................... 1301 0.68 0.028 2.7
Middle Loxahatchee.......................... 1302 0.98 0.044 3.9
Upper Loxahatchee........................... 1303 1.25 0.072 3.6
St. Lucie:
Lower St. Lucie............................. 1401 0.58 0.045 5.3
Middle St. Lucie............................ 1402 0.90 0.120 8.4
Upper St. Lucie............................. 1403 1.22 0.197 8.9
Indian River Lagoon:
Mosquito Lagoon............................. 1501 1.18 0.078 7.5
Banana River................................ 1502 1.17 0.036 5.7
Upper Indian River Lagoon................... 1503 1.63 0.074 9.2
Upper Central Indian River Lagoon........... 1504 1.33 0.076 9.2
Lower Central Indian River Lagoon........... 1505 1.12 0.117 8.7
Lower Indian River Lagoon................... 1506 0.49 0.037 4.0

[[Page 74982]]

Halifax River:
Upper Halifax River......................... 1601 0.75 0.243 9.4
Lower Halifax River......................... 1602 0.63 0.167 9.6
Guana, Tolomato, Matanzas, Pellicer:
Upper GTMP.................................. 1701 0.77 0.144 9.5
Lower GTMP.................................. 1702 0.53 0.108 6.1
Lower St. Johns River:
Lower St. Johns River....................... 1801 0.75 0.095 2.5
Trout River................................. 1802 1.09 0.108 3.6
Trout River................................. 1803 1.15 0.074 7.7
Nassau River:
Lower Nassau................................ 1901 0.33 0.113 3.2
Middle Nassau............................... 1902 0.40 0.120 2.4
Upper Nassau................................ 1903 0.75 0.125 3.4
St. Marys River:
Lower St. Marys River....................... 2002 0.27 0.045 3.0
Middle St. Marys River...................... 2003 0.44 0.036 2.7
----------------------------------------------------------------------------------------------------------------
\1\ Chlorophyll a is defined as corrected chlorophyll, or the concentration of chlorophyll a remaining after the
chlorophyll degradation product, phaeophytin a, has been subtracted from the uncorrected chlorophyll a
measurement.
* For a given water body, the annual geometric mean of TN, TP, or chlorophyll a, concentrations shall not exceed
the applicable criterion concentration more than once in a three-year period.
\+\ In these four areas (collectively referred to as the ``Big Bend region''), coastal and estuarine waters are
combined. Criteria for the Big Bend region apply to the coastal and estuarine waters in that region.

(2) Criteria for Tidal Creeks.
The applicable total nitrogen (TN), total phosphorus (TP), and
chlorophyll a criteria for predominantly marine tidal creeks are shown
in Sec. 131.45(c)(1), Table 1. The applicable TN and TP criteria for
predominantly freshwater tidal creeks are shown in Table 2.

Table 2--EPA's Numeric Criteria for Florida's Predominantly Freshwater
Tidal Creeks
------------------------------------------------------------------------
Instream protection
value criteria
Nutrient watershed region ---------------------
TN (mg/ TP (mg/
L) * L) *
------------------------------------------------------------------------
Panhandle West \a\................................ 0.67 0.06
Panhandle East \b\................................ 1.03 0.18
North Central \c\................................. 1.87 0.30
West Central \d\.................................. 1.65 0.49
Peninsula \e\..................................... 1.54 0.12
------------------------------------------------------------------------
Watersheds pertaining to each Nutrient Watershed Region (NWR) were based
principally on the NOAA coastal, estuarine, and fluvial drainage areas
with modifications to the NOAA drainage areas in the West Central and
Peninsula Regions that account for unique watershed geologies. For
more detailed information on regionalization and which WBIDs pertain
to each NWR, see the Technical Support Document.
\a\ Panhandle West region includes: Perdido Bay Watershed, Pensacola Bay
Watershed, Choctawhatchee Bay Watershed, St. Andrews Bay Watershed,
Apalachicola Bay Watershed.
\b\ Panhandle East region includes: Apalachee Bay Watershed, and
Econfina/Steinhatchee Coastal Drainage Area.
\c\ North Central region includes the Suwannee River Watershed.
\d\ West Central region includes: Peace, Myakka, Hillsborough, Alafia,
Manatee, Little Manatee River Watersheds, and small, direct Tampa Bay
tributary watersheds south of the Hillsborough River Watershed.
\e\ Peninsula region includes: Waccasassa Coastal Drainage Area,
Withlacoochee Coastal Drainage Area, Crystal/Pithlachascotee Coastal
Drainage Area, small, direct Tampa Bay tributary watersheds west of
the Hillsborough River Watershed, Sarasota Bay Watershed, small,
direct Charlotte Harbor tributary watersheds south of the Peace River
Watershed, Caloosahatchee River Watershed, Estero Bay Watershed,
Kissimmee River/Lake Okeechobee Drainage Area, Loxahatchee/St. Lucie
Watershed, Indian River Watershed, Daytona/St. Augustine Coastal
Drainage Area, St. Johns River Watershed, Nassau Coastal Drainage
Area, and St. Marys River Watershed.
* For a given water body, the annual geometric mean of TN or TP
concentrations shall not exceed the applicable criterion concentration
more than once in a three-year period.

(3) Criteria for Marine Lakes.
The applicable total nitrogen (TN), total phosphorus (TP) and
chlorophyll a criteria for marine lakes are shown in Table 3.

Table 3--EPA's Numeric Criteria for Florida's Marine Lakes
----------------------------------------------------------------------------------------------------------------
EPA final EPA final TN and TP criteria [range]
Long term average lake color \a\ and alkalinity Chl[dash]a \b,*\ ---------------------------------------
[mu]g/L TN mg/L TP mg/L
----------------------------------------------------------------------------------------------------------------
Colored lakes \c\................................... 20 1.27 0.05
[1.27-2.23] [0.05-0.16]

[[Page 74983]]

Clear lakes, high alkalinity \d\.................... 20 1.05 0.03
[1.05-1.91] [0.03-0.09]
Clear lakes, low alkalinity \e\..................... 6 0.51 0.01
[0.51-0.93] [0.01-0.03]
----------------------------------------------------------------------------------------------------------------
\a\ Platinum-cobalt units (PCU) assessed as true color free from turbidity
\b\ Chl-a is defined as corrected chlorophyll, or the concentration of chl-a remaining after the chlorophyll
degradation product, phaeophytin a, has been subtracted from the uncorrected chl-a measurement.
\c\ Long-term color > 40 PCU and alkalinity > 20 mg/L CaCO3
\d\ Long-term color <= 40 PCU and alkalinity > 20 mg/L CaCO3
\e\ Long-term color <= 40 PCU and alkalinity <= 20 mg/L CaCO3
* For a water body, the annual geometric mean of chl-a, TN or TP concentrations shall not exceed the applicable
criterion concentration more than once in a three-year period.

(4) Criteria for Coastal Waters.
The applicable chlorophyll a criteria for coastal waters are shown
in Table 4.

Table 4--EPA's Numeric Criteria for Florida's Coastal Waters
----------------------------------------------------------------------------------------------------------------
Coastal ChlorophyllRS-a \1\*
Coastal region segment \+\ Approximate location (mg/m\3\)
----------------------------------------------------------------------------------------------------------------
Panhandle.................................. 1 Alabama border............... 2.41
2 Pensacola Bay Pass........... 2.57
3 ............................. 1.44
4 ............................. 1.16
5 ............................. 1.06
6 ............................. 1.04
7 ............................. 1.14
8 Choctawhatchee Bay Pass...... 1.23
9 ............................. 1.08
10 ............................. 1.09
11 ............................. 1.11
12 ............................. 1.18
13 ............................. 1.45
14 St. Andrews Bay Pass......... 1.74
15 St. Joseph Bay Pass.......... 2.75
16 ............................. 2.39
17 Southeast St. Joseph Bay..... 3.47
West Florida Shelf......................... 18 ............................. 3.96
19 Tampa Bay Pass............... 4.45
20 ............................. 3.37
21 ............................. 3.25
22 ............................. 2.95
23 ............................. 2.79
24 ............................. 2.98
25 ............................. 3.24
26 Charlotte Harbor............. 4.55
27 ............................. 4.22
28 ............................. 3.67
29 ............................. 4.16
30 ............................. 5.70
31 ............................. 4.54
32 ............................. 4.03
33 Fort Myers................... 4.61
Atlantic Coast............................. 34 Biscayne Bay................. 0.92
35 ............................. 0.26
36 ............................. 0.26
37 ............................. 0.24
38 ............................. 0.21
39 ............................. 0.21
40 ............................. 0.20
41 ............................. 0.20
42 ............................. 0.21
43 ............................. 0.25
44 ............................. 0.57
45 St. Lucie Inlet.............. 1.08
46 ............................. 1.42

[[Page 74984]]

47 ............................. 1.77
48 ............................. 1.55
49 ............................. 1.44
50 ............................. 1.53
51 ............................. 1.31
52 ............................. 1.40
53 ............................. 1.80
54 Canaveral Bight.............. 2.73
55 ............................. 2.33
56 ............................. 2.28
57 ............................. 2.06
58 ............................. 1.92
59 ............................. 1.76
60 ............................. 1.72
61 ............................. 2.04
62 ............................. 1.92
63 ............................. 1.86
64 ............................. 1.95
65 ............................. 2.41
66 ............................. 2.76
67 ............................. 2.80
68 ............................. 3.45
69 Nassau Sound................. 3.69
70 ............................. 3.78
71 Georgia border............... 4.22
----------------------------------------------------------------------------------------------------------------
\1\ ChlorophyllRS-a is remotely sensed calculation of chlorophyll a concentrations.
* For a given water body, the annual geometric mean of the chlorophyll a concentration shall not exceed the
applicable criterion concentration more than once in a three-year period.
\+\ Please see TSD for location of Coastal Segments (Volume 2: Coastal Waters, Section 1.3).

(5) Criteria for South Florida Inland Flowing Waters.
The applicable criteria for south Florida inland flowing waters
that flow into downstream estuaries include the downstream protection
value (DPV) for total nitrogen (TN) and total phosphorus (TP) derived
pursuant to the provisions of Sec. 131.45(c)(6). These criteria are
not applicable to waters within the lands of the Miccosukee and
Seminole Tribes, the Everglades Protection Area (EvPA), or the
Everglades Agricultural Area (EAA).
(6) Criteria for Protection of Downstream Estuaries and South
Florida marine waters. (i) A downstream protection value (DPV) for
stream tributaries that flow into a downstream estuary or south Florida
marine water (i.e., downstream water) is the allowable concentration of
total nitrogen (TN) and/or total phosphorus (TP) applied at the point
of entry into the downstream water. The applicable DPV for any stream
flowing into a downstream water shall be determined pursuant to
paragraphs (c)(6)(ii), (iii), (iv), or (v) of this section. The methods
available to derive DPVs should be considered in the order listed.
Contributions from stream tributaries upstream of the point of entry
location must result in attainment of the DPV at the point of entry
into the downstream water. If the DPV is not attained at the point of
entry into the downstream water, then the collective set of streams in
the upstream watershed does not attain the DPV, which is an applicable
water quality criterion for the water segments in the upstream
watershed. The State or EPA may establish additional DPVs at upstream
tributary locations that are consistent with attaining the DPV at the
point of entry into the downstream water. The State or EPA also have
discretion to establish DPVs to account for a larger watershed area
(i.e., include waters beyond the point of reaching water bodies that
are not streams as defined by this rule).
(ii) In instances where available data and/or resources provide for
use of a scientifically defensible and protective system-specific
application of water quality simulation models with results that
protect the designated uses and meet all applicable numeric nutrient
criteria for the downstream water, the State or EPA may derive the DPV
for TN and TP from use of a system-specific application of water
quality simulation models. The State or EPA may designate the wasteload
and/or load allocations from a TMDL established or approved by EPA as
DPV(s) if the allocations from the TMDL will protect the downstream
water's designated uses and meet all applicable numeric nutrient
criteria for the downstream water.
(iii) When the State or EPA has not derived a DPV for a stream
pursuant to paragraph (c)(6)(ii) of this section, and where a reference
condition approach is used to derive the downstream water's TN, TP and
chlorophyll a criteria, then the State or EPA may derive the DPV for TN
and TP using a reference condition approach based on TN and TP
concentrations from the stream pour point, coincident in time with the
data record from which the downstream receiving water segment TN and TP
criteria were developed, and using the same data screens and reference
condition approach as were applied to the downstream water's data.
(iv) When the State or EPA has not derived a DPV pursuant to
paragraph (c)(6)(ii) or (c)(6)(iii) of this section, then the State or
EPA may derive the DPV for TN and TP using dilution models based on the
relationship between salinity and nutrient concentrations.
(v) When the State or EPA has not derived a DPV pursuant to
paragraph (c)(6)(ii), (c)(6)(iii), or (c)(6)(iv) of this section, then
the DPV for TN and TP is the applicable TN and TP criteria for the
receiving segment of the downstream water as described in Sec.
131.45(c)(1), or as described in Section 62-302.532(a)-(h), F.A.C. for
downstream waters where EPA-approved State criteria apply.

[[Page 74985]]

(vi) The State and EPA shall maintain a record of DPVs they derive
based on the methods described in paragraphs (c)(6)(ii), (iii), (iv),
and (v) of this section, as well as a record supporting their
derivation, and make such records available to the public. The State
and EPA shall notify one another and provide a supporting record within
30 days of derivation of DPVs pursuant to paragraphs (c)(6)(i), (ii),
(iii), (iv), or (v) of this section. DPVs derived pursuant to these
paragraphs do not require EPA approval under Clean Water Act Sec.
303(c) to take effect.
(d) Applicability. (1) The criteria in paragraphs (c)(1) through
(6) of this section apply to certain Class I, Class II, and Class III
waters in Florida, and apply concurrently with other applicable water
quality criteria, except when:
(i) State water quality standards contain criteria that are more
stringent for a particular parameter and use;
(ii) The Regional Administrator determines that site-specific
alternative criteria apply pursuant to the procedures in paragraph (e)
of this section; or
(iii) The State adopts and EPA approves a water quality standards
variance to the Class I, Class II, or Class III designated use pursuant
to Sec. 131.13 that meets the applicable provisions of State law and
the applicable Federal regulations at Sec. 131.10.
(2) The criteria established in this section are subject to the
State's general rules of applicability in the same way and to the same
extent as are the other Federally-adopted and State-adopted numeric
criteria when applied to the same use classifications.
(e) Site-specific Alternative Criteria.
(1) The Regional Administrator may determine that site-specific
alternative criteria shall apply to specific surface waters in lieu of
the criteria established in paragraph (c) of this section. Any such
determination shall be made consistent with Sec. 131.11.
(2) To receive consideration from the Regional Administrator for a
determination of site-specific alternative criteria, an entity shall
submit a request that includes proposed alternative numeric criteria
and supporting rationale suitable to meet the needs for a technical
support document pursuant to paragraph (e)(3) of this section. The
entity shall provide the State a copy of all materials submitted to
EPA, at the time of submittal to EPA, to facilitate the State providing
comments to EPA. Site-specific alternative criteria may be based on one
or more of the following approaches.
(i) Replicate the process for developing the estuary criteria in
paragraph (c)(1) of this section.
(ii) Replicate the process for developing the tidal creek criteria
in paragraph (c)(2) of this section.
(iii) Replicate the process for developing the marine lake criteria
in paragraph (c)(3) of this section.
(iv) Replicate the process for developing the coastal criteria in
paragraph (c)(4) of this section.
(v) Replicate the process for developing the south Florida inland
flowing water criteria in paragraph (c)(5) of this section.
(vi) Conduct a biological, chemical, and physical assessment of
water body conditions.
(vii) Use another scientifically defensible approach protective of
the designated use.
(3) For any determination made under paragraph (e)(1) of this
section, the Regional Administrator shall, prior to making such a
determination, provide for public notice and comment on a proposed
determination. For any such proposed determination, the Regional
Administrator shall prepare and make available to the public a
technical support document addressing the specific surface waters
affected and the justification for each proposed determination. This
document shall be made available to the public no later than the date
of public notice issuance.
(4) The Regional Administrator shall maintain and make available to
the public an updated list of determinations made pursuant to paragraph
(e)(1) of this section as well as the technical support documents for
each determination.
(5) Nothing in this paragraph (e) shall limit the Administrator's
authority to modify the criteria in paragraph (c) of this section
through rulemaking.
(f) Effective date. This section is effective [date 60 days after
publication of final rule].
[FR Doc. 2012-30117 Filed 12-17-12; 8:45 am]
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