The purpose of the rule is to adopt Total Maximum Daily Loads (TMDLs), and their allocations, for certain waters impaired for nutrients and dissolved oxygen in the Springs Coast Basin. Furthermore, upon paragraph 62-302.531(2)(a), F.A.C., becoming ...

DEPARTMENT OF ENVIRONMENTAL PROTECTION

RULE NO.:RULE TITLE:
62-304.645Springs Coast Basin TMDLs
PURPOSE AND EFFECT: The purpose of the rule is to adopt Total Maximum Daily Loads (TMDLs), and their allocations, for certain waters impaired for nutrients and dissolved oxygen in the Springs Coast Basin. Furthermore, upon paragraph 62-302.531(2)(a), F.A.C., becoming effective, these nutrient TMDLs will constitute site specific numeric interpretations of the narrative nutrient criterion set forth in paragraph 62-302.530(47)(b), F.A.C.
SUMMARY: These TMDLs address certain dissolved oxygen and nutrient impairments in the Springs Coast Basin. Specifically, the TMDL rules being proposed for adoption are for the Curlew Creek tidal segment and the McKay Creek tidal segment. These waterbodies were verified as impaired for dissolved oxygen and nutrients, due to elevated chlorophyll a concentrations, using the methodology established in Chapter 62-303, F.A.C., Identification of Impaired Surface Waters. This rulemaking has been given an OGC case number 12-1360.
SUMMARY OF STATEMENT OF ESTIMATED REGULATORY COSTS AND LEGISLATIVE RATIFICATION:
The Agency has determined that this will have an adverse impact on small business or likely increase directly or indirectly regulatory costs in excess of $200,000 in the aggregate within one year after the implementation of the rule. A SERC has been prepared by the agency.
The projected costs are primarily attributable to anticipated activities associated with the local MS4.
The Agency has determined that the proposed rule is expected to require legislative ratification based on the statement of estimated regulatory costs.
Any person who wishes to provide information regarding a statement of estimated regulatory costs, or provide a proposal for a lower cost regulatory alternative must do so in writing within 21 days of this notice.
RULEMAKING AUTHORITY: 403.061, 403.067 FS.
LAW IMPLEMENTED: 403.061, 403.062, 403.067 FS.
IF REQUESTED WITHIN 21 DAYS OF THE DATE OF THIS NOTICE, A HEARING WILL BE SCHEDULED AND ANNOUNCED IN THE FAR.
THE PERSON TO BE CONTACTED REGARDING THE PROPOSED RULE IS: Jan Mandrup-Poulsen, Division of Environmental Assessment and Restoration, Bureau of Watershed Restoration, Mail Station 3555, Florida Department of Environmental Protection, 2600 Blair Stone Road, Tallahassee, Florida 32399-2400, telephone [phone]. For the 21 day period after this notice, the Department will accept written comments on the establishment of these nutrient TMDLs as site specific interpretations of the narrative nutrient criterion. Written comments should be directed to Jan Mandrup-Poulsen at the address above.

THE FULL TEXT OF THE PROPOSED RULE IS:

62-304.645 Springs Coast Basin TMDLs.

(1) through (12) No change.

(13) Curlew Creek Tidal Segment.  The TMDL to address the low dissolved oxygen and nutrient impairments  is an annual average TN concentration of 0.95 mg/L and is allocated as follows:

(a) The WLA for the Mid-County Wastewater Treatment Plant is 4,245 lb/year of TN,

(b) The WLA for discharges subject to the Department’s NPDES Municipal Stormwater Permitting Program is to address anthropogenic sources in the basin such that in-stream concentrations meet the Class III marine dissolved oxygen and nutrient criteria which, based on the measured concentrations in the year 2011, will require a 15 percent reduction of TN at sources contributing to exceedances of the criteria,

(c) The LA for nonpoint sources is to address anthropogenic sources in the basin such that in-stream concentrations meet the Class III marine dissolved oxygen and nutrient criteria which, based on the measured concentrations in the year 2011, will require a 15 percent reduction of TN at sources contributing to exceedances of the criteria, and

(d) The Margin of Safety is implicit.

(e) While the LA and WLA for TN have been expressed as the pounds allowed and the percent reductions needed to attain the applicable Class III criteria, it is the combined reductions from both anthropogenic point and nonpoint sources that will result in the required reduction of in-stream TN concentration. However, it is not the intent of the TMDL to abate natural background conditions.

(14) McKay Creek Tidal Segment.  The TMDLs to address the low dissolved oxygen and nutrient impairments are an annual TN load of 15,563 lb/year and an annual 5-day BOD load of 32,505 lb/year and are allocated as follows:

(a) The WLA for wastewater sources is not applicable,

(b) The WLA for discharges subject to the Department’s NPDES Municipal Stormwater Permitting Program is to address anthropogenic sources in the basin such that in-stream concentrations meet the dissolved oxygen criterion and nutrient criterion, expressed as a chlorophyll a target, which, based on the calculated loadings from the 2002–2011 period, will require a 45 percent reduction of TN and 45 percent reduction of 5-day BOD at sources contributing to exceedances of the criteria,

(c) The LAs for nonpoint sources are to address anthropogenic sources in the basin such that in-stream concentrations meet the dissolved oxygen criterion and nutrient criterion, expressed as a chlorophyll a target, which, based on the calculated loadings from the 2002–2011 period, will require a 45 percent reduction of TN and 45 percent reduction of 5-day BOD at sources contributing to exceedances of the criteria, and

(d) The Margin of Safety is implicit.

(e) While the LAs for TN and 5-day BOD have been expressed as the percent reductions needed to attain the applicable Class III criteria, it is the combined reductions from both anthropogenic point and nonpoint sources that will result in the required reduction of in-stream TN and 5-day BOD concentrations. However, it is not the intent of the TMDL to abate natural background conditions.

Rulemaking Authority 403.061, 403.067 FS. Law Implemented 403.061, 403.062, 403.067 FS. History–New 6-3-08, Amended 11-14-12,__________.

 NAME OF PERSON ORIGINATING PROPOSED RULE: Drew Bartlett, Director, Division of Environmental Assessment and Restoration
NAME OF AGENCY HEAD WHO APPROVED THE PROPOSED RULE: Herschel T. Vinyard Jr., Secretary
DATE PROPOSED RULE APPROVED BY AGENCY HEAD: January 24, 2013
DATE NOTICE OF PROPOSED RULE DEVELOPMENT PUBLISHED IN FAR: November 23, 2011