United States                   Off ice of Water                EPA-823-F-10-003
                Environmental Protection Agency         4305T                        July 2010
                Water Quality Standards  for the
                State of Florida's Lakes and Flowing
                Waters; Supplemental  Notice of Data
                Availability and Request for
EPA is providing a supplemental notice of data availability and a request for comment related to
EPA's January 26, 2010 notice of proposed rulemaking, "Water Quality Standards for the State
of Florida's Lakes and Flowing Waters" (75 FR 4173).

On January 26, 2010, EPA published proposed "Water Quality Standards for the State of
Florida's Lakes and Flowing Waters" (75 FR 4173).  EPA conducted 13 public hearing sessions
in six cities in Florida and held a 90-day public comment period as part of the proposed rule
generating over 22,000 public comments. EPA is reviewing and considering these comments in
preparation of the final rule, which is scheduled to be published  on October 15, 2010.

About this action
This notice reflects a review of comments and new information received by EPA as part of the
public comment process. EPA is requesting further comment on possible revisions and new
information related to specific approaches and issues identified in the January 26, 2010 proposal.
EPA is only seeking comment on the items presented in this supplemental notice.

In the January 2010 proposed rule, EPA proposed to  classify Florida's streams into four regions
for application of total phosphorus (TP) and total nitrogen (TN)  criteria. Streams within each of
these regions (Panhandle, Bone Valley, Peninsula and North Central) reflect similar underlying
geology (such as phosphorus-rich soils), nutrient concentrations and nutrient ratios. In this
notice, EPA is requesting comment on revised stream region boundaries based on additional
information about watershed delineations and phosphorus-rich geological formations in Florida.
This revised regionalization approach would result in five TP and TN regions for Florida's
streams and a re-delineation of certain watershed boundaries for the Bone Valley and Peninsula

In January 2010, EPA proposed to use the 75th percentile of sites with healthy biological
condition as measured by the Stream Condition Index (SCI) as the basis for deriving Florida's
stream criteria and also requested comment on an alternative benchmark distribution approach.
In this notice, EPA is requesting  comment on basing  the TN and TP criteria for the revised

Nutrient Watershed Regions on a combination of the 75th and 90th percentile values (depending
on region) of the benchmark sites outlined in the alternate approach at proposal, with additional
data quality screens applied. EPA is continuing to consider the primary SCI approach proposed
in January 2010.

The January 2010 proposal also proposed application of the Vollenweider equation to ensure that
nutrient criteria in streams are protective of downstream lakes and requested comment on
alternative approaches including the BATHTUB model (75 FR 4198). This notice requests
additional comment on using the BATHTUB model in place of the Vollenweider equation,
allowing the use of alternative models under certain circumstances, and providing for additional
approaches to protect downstream lakes when limited data are available.

EPA is seeking comment only on the aspects identified in this supplemental notice and will
consider the comments received before finalizing the proposed rule, "Water Quality Standards
for the State of Florida's Lakes and Flowing Waters." This notice focuses solely on the
delineation of stream nutrient regions and protection of downstream lakes in Florida and EPA is
not soliciting comment on any other provisions of the January 2010 proposal.

To get more information
Contact Danielle Salvaterra at (202) 564-1649 or salvaterra.danielle@epa.gov, or visit