The purpose of the rule is to adopt Total Maximum Daily Loads (TMDLs), and their allocations, for certain waters impaired for dissolved oxygen (DO) and/or nutrients in the Indian River Lagoon Basin. Furthermore, upon paragraph 62-302.531(2)(a), F.A....

 

DEPARTMENT OF ENVIRONMENTAL PROTECTION

RULE NO.: RULE TITLE:
62-304.520: Indian River Lagoon 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 dissolved oxygen (DO) and/or nutrients in the Indian River Lagoon Basin. Furthermore, upon paragraph 62-302.531(2)(a), F.A.C., becoming effective, the nutrient TMDL for the Eau Gallie River in subsection 62-304.520(15), F.A.C., will constitute a site specific numeric interpretation of the narrative nutrient criterion set forth in paragraph 62-302.530(47)(b), F.A.C.
SUMMARY: These TMDLs address certain DO and nutrient impairments in the Indian River Lagoon Basin. Specifically, DO and nutrient TMDL rules being proposed for adoption are for the Eau Gallie River, Crane Creek, the C-54 Canal at Confluence with the Sebastian River, the South Prong Sebastian River Estuary Segment, and the Sebastian River above the Indian River. DO-only TMDLs are being proposed for Addison Creek, the North Prong Sebastian River, and the South Prong Sebastian River Freshwater Segment. These waterbodies were verified for nutrient and/or DO impairments due to elevated chlorophyll a concentrations and/or depressed DO concentrations using the methodology established in Chapter 62-303, F.A.C., Identification of Impaired Surface Waters. Based on results from water quality modeling and statistical analyses, it was demonstrated that the low DO condition in these impaired waters were mainly caused by loads of biochemical oxygen demand (BOD) and sediment oxygen demand (SOD) resulting from the long-term accumulation of BOD in the sediment. Therefore, BOD loading limits were established by these proposed TMDLs to restore the DO condition in these impaired waters. Using statistical analyses of spatial and temporal patterns of nutrient-related data in nutrient impaired waters, it was determined that the observed elevation in chlorophyll a concentrations in most nutrient impaired water segments, except for the Eau Gallie River, were mainly caused by receiving water processes under extreme weather conditions instead of by elevated watershed nutrient loadings. Therefore, the nutrient loading targets for nutrient impaired water segments were established to be consistent with the nutrient loading targets adopted previously into this rule to protect the seagrass communities in the mainstem of Indian River Lagoon. Because the Eau Gallie River showed consistent long-term elevation in chlorophyll a concentration compared to other water segments in the same area, nutrient reduction goals more stringent than those adopted previously for the same watershed area were establish to restore the nutrient condition in the river. The watershed nutrient and BOD loads were simulated using the Hydrological Simulation Program – Fortran (HSPF) and the Pollutant Load Screening Model (PLSM). The DO and chlorophyll a dynamics in receiving waters were simulated using the HSPF model and the Environmental Fluid Dynamic Code (EFDC) model. This rulemaking has been given an OGC case number 12-1681.
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.
Specifically, three separate SERC analyses have been prepared by the Agency for watershed areas of (1) the Sebastian River system, including the North Prong Sebastian River, the C-54 Canal at Confluence with the Sebastian River, the South Prong Sebastian River Freshwater Segment, the South Prong Sebastian River Estuary Segment, and the Sebastian River above the Indian River, (2) the Eau Gallie River and Crane Creek, and (3) Addison Creek.
The Agency has determined that these proposed rules are expected to require legislative ratification based on the statement of estimated regulatory costs. However, the TMDL proposed for Addison Creek will not increase the regulatory costs in excess of $1.0 million and is not expected to require legislative ratification.
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 the Eau Gallie River nutrient TMDL as a site specific interpretation 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:

62-304.520 Indian River Lagoon TMDLs.

(1) – (13) No change.

(14) Addison Creek: The dissolved oxygen (DO) TMDL for Addison Creek is 35,605 lb/year of biochemical Oxygen Demand (BOD) and is 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 a 72.3% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005,

(c) The LA for nonpoint sources is a 72.3% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and

(d) The Margin of Safety is implicit.

(e) While the LA for BOD has been expressed as the percent reduction needed to attain the applicable Class III DO criteria, it is the combined reductions from both anthropogenic point and nonpoint sources that will result in the restoration of DO condition in the impaired waterbody. However, it is not the intent of this TMDL to abate natural background conditions.

(15) Eau Gallie River: The DO and nutrient TMDLs for the Eau Gallie River are 28,842 lb/year of TN, 4,307 lb/year of TP, and 70,056 lb/year of BOD and are allocated as follows:

(a) The WLA of TN and TP for the Melbourne Reverse Osmosis is  the TN and TP loading limits established in 62-304.520(6)(a), F.A.C. for the facility.  The WLA of BOD is not applicable,

(b) The WLA for discharges subject to the Department’s NPDES Municipal Stormwater Permitting Program is a 51.0% reduction of TN, 58.0% reduction of TP, and 86.3% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005,

(c) The LA for nonpoint sources is a 51.0% reduction of TN, 58.0% reduction of TP, and 86.3% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and

(d) The Margin of Safety is implicit.

(e) While the LAs for nutrients and BOD have been expressed as the percent reductions needed to attain the applicable Class III nutrient and DO criteria, it is the combined reductions from both anthropogenic point and nonpoint sources that will result in the restoration of nutrient and DO conditions in the impaired waterbody. However, it is not the intent of the TMDL to abate natural background conditions.

(16) Crane Creek: The DO and nutrient TMDLs for Crane Creek is 110,547 lb/year of BOD and the TN and TP percent reduction established in 62-304.520(7)(b)1. and 2. , F.A.C.  These TMDLs are allocated as follows:

(a) The WLA of TN and TP  for the Melbourne Grant Street Wastewater Treatment Facility is the TN and TP loading limits established in 62-304.520(7)(a), F.A.C. for the facility.  The WLA of BOD granted to the facility is 139 lb/year,

(b) The WLA for discharges subject to the Department’s NPDES Municipal Stormwater Permitting Program is a 80.1% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and the TN and TP reductions established in 62-304.520(7)(b)1., F. A. C.,

(c) The LA for nonpoint sources is a 80.1% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and the TN and TP reductions established in 62-304.520(7)(b)2, F. A. C., and

(d) The Margin of Safety is implicit.

(e) While the WLA and LA for nutrients and BOD have been expressed as the percent reductions needed to attain the applicable Class III nutrients and DO criteria, it is the combined reductions from both anthropogenic point and nonpoint sources that will result in the restoration of nutrient and DO conditions in the impaired waterbody. However, it is not the intent of the TMDL to abate natural background conditions.

(17) North Prong Sebastian River: The DO TMDL for the North Prong Sebastian River is 282,346 lb/year of BOD, and is allocated as follows:

(a) The WLA to the Barefoot Bay Advanced Wastewater Treatment Facility is 2,707 lb/year  of BOD,

(b) The WLA for discharges subject to the Department’s NPDES Municipal Stormwater Permitting Program is 69.7% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005,

(c) The LA for nonpoint sources is 69.7% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and

(d) The Margin of Safety is implicit.

(e) While the WLA and LA for BOD have been expressed as the percent reduction needed to attain the applicable Class III DO criteria, it is the combined reductions from both anthropogenic point and nonpoint sources that will result in the restoration of DO condition in the impaired waterbody. However, it is not the intent of the TMDL to abate natural background conditions.

(18) C-54 Canal at Confluence with the Sebastian River: The DO and nutrient TMDLs for C-54 Canal at Confluence with the Sebastian River is 834,397 lb/year of BOD and the TN and TP percent reduction  established in 62-304.520(7)(b)1,  and 2, F. A. C.  These TMDLs 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 a 72.3% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and the TN and TP reductions established in 62-304.520(7)(b)1, F. A. C.,

(c) The LAs for nonpoint sources are 72.3% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and the TN and TP reductions established in 62-304.520(7)(b)2, F. A. C., and

(d) The Margin of Safety is implicit.

(e) While the WLA and LA for nutrients and BOD have been expressed as the percent reductions needed to attain the applicable Class III nutrients and DO criteria, it is the combined reductions from both anthropogenic point and nonpoint sources that will result in the restoration of nutrient and DO conditions in the impaired waterbody. However, it is not the intent of the TMDL to abate natural background conditions.

(19) South Prong Sebastian River Freshwater Segment and South Prong Sebastian River Estuary Segment: The DO and nutrient TMDLs for the South Prong Sebastian River Freshwater Segment and the South Prong Sebastian River Estuary Segment is 515,178 lb/year BOD and the TN and TP percent reduction established in 62-304.520(7)(b)1,  and 2, F. A. C.  These TMDLs 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 a 78.2% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and the TN and TP loads reductions established in 62-304.520(7)(b)1, F. A. C.,

(c) The LA for nonpoint sources is a 78.2% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and the TN and TP reductions established in 62-304.520(7)(b)2, F. A. C., and

(d) The Margin of Safety is implicit.

(e) While the WLA and LA for nutrients and BOD have been expressed as the percent reductions needed to attain the applicable Class III nutrients and DO criteria, it is the combined reductions from both anthropogenic point and nonpoint sources that will result in the restoration of nutrient and DO conditions in these impaired water segments. However, it is not the intent of these TMDLs to abate natural background conditions.

(20) Sebastian River above the Indian River: The DO and nutrient TMDLs for the Sebastian River above the Indian River  is 1,722,130 lb/year of BOD and the TN and TP percent reduction established in 62-304.520(7)(b)1,  and 2, F. A. C.  These TMDLs 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 a 74.2% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and the TN and TP reductions established in 62-304.520(7)(b)1, F. A. C.,

(c) The LA for nonpoint sources is a 74.2% reduction of BOD based on the year 2000 landuse and a modeling period from 1996 through 2005, and the TN and TP reductions established in 62-304.520(7)(b)2, F. A. C., and

(d) The Margin of Safety is implicit.

(e) While the WLA and LA for nutrients and BOD have been expressed as the percent reductions needed to attain the applicable Class III nutrient and DO criteria, it is the combined reductions from both anthropogenic point and nonpoint sources that will result in the restoration of nutrient and DO conditions in these impaired water segments. However, it is not the intent of these TMDLs 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 3-26-09, _________.

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: February 7, 2013
DATE NOTICE OF PROPOSED RULE DEVELOPMENT PUBLISHED IN FAR: November 23, 2011