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 Comment Summary 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). Background 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 regions. 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 www.epa.gov/waterscience/standards/rules/florida/. ------- |