40C-42.023: Requirements for Issuance
40C-42.091: Publications Incorporated by Reference
40C-42.900: Forms and Instructions
PURPOSE AND EFFECT: The purposes of this proposed rule amendment are to (1) amend and update the environmental resource permit (ERP) application forms to reflect both the new criteria for the Wekiva Recharge Protection Basin and current ERP criteria and terminology, (2) create recharge criteria for certain systems located within the Wekiva Recharge Protection Basin that require an ERP pursuant to Chapters 40C-4, 40C-40, 40C-42, or 40C-44, F.A.C., (3) update Sections 3.3.1(b) and 3.3.2(f) of the Applicants Handbook (A.H.) to reflect the current threshold in paragraph 40C-42.022(1)(b) and 3.3.2(f), F.A.C., (4) update section 3.3.2(f), A.H., to reflect the current threshold in paragraph 40C-42.022(2)(f), F.A.C., (5) update Sections 11.1, 13.1, and 15.1, A.H., to reference current Chapter 62-555, F.A.C., and (6) update sections 14.3 and 14.4, A.H., to reflect the current wet detention design and performance criteria in paragraphs 40C-42.026(4)(b) and (4)(g), F.A.C. The effects of the proposed amendment are to (1) make the ERP application forms reflect both the new criteria of the Wekiva Recharge Protection Basin and current Stormwater ERP rule criteria and terminology, (2) require applications to demonstrate that systems within the Wekiva Recharge Protection Basin either retain three inches of runoff from all impervious areas proposed to be constructed on type A soils (and percolating into the soils within 72 hours) or otherwise demonstrate that the post-development recharge capacity is equal to or greater than the pre-development recharge capacity, (3) update existing Stormwater ERP thresholds and criteria to reflect current thresholds and criteria in Chapter 40C-42, F.A.C., and (4) update references to current Chapter 62-555, F.A.C.
SUMMARY: The proposed rule amendments would amend and update the ERP application form in Sections D, E, and H of Form 40C-4.900(1), create recharge criteria for certain systems located within the Wekiva Recharge Protection Basin requiring a Stormwater ERP in paragraph 40C-42.023(1)(d), F.A.C., update Stormwater ERP thresholds in sections 3.3.1(b) and 3.3.2(f), A.H., to reflect current thresholds, update references to current Chapter 62-555, F.A.C., update wet detention design and performance criteria in sections 14.3 and 14.4, A.H., to reflect current design and performance criteria.
SUMMARY OF ESTIMATED REGULATORY COSTS: No Statement of Estimated Regulatory Cost was prepared.
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.
SPECIFIC AUTHORITY: 369.318, 373.044, 373.113, 373.418 FS.
LAW IMPLEMENTED: 369.318, 373.413, 373.414, 373.415, 373.416, 373.418, 373.426, 373.461 FS.
THE PERSON TO BE CONTACTED REGARDING THE PROPOSED RULE IS: Norma Messer, Rules Coordinator, Office of General Counsel, St. Johns River Water Management District, 4049 Reid Street, Palatka, Florida 32177-2529, (386)329-4459, Suncom 860-4459 or email address nmesser@sjrwmd.com
THE FULL TEXT OF THE PROPOSED RULE IS:
40C-42.023 Requirements for Issuance.
(1) To receive a standard general or individual permit under this chapter the applicant must provide reasonable assurance based on plans, test results and other information, that the stormwater management system:
(a) through (c) No change.
(d) Meets any applicable basin criteria contained in paragraph 40C-41.063(3)(a), and subsections (7), and (8), F.A.C.
(2) No change.
Specific Authority 369.318, 373.044, 373.113, 373.171, 373.418 FS. Law Implemented 369.318, 373.413, 373.414, 373.415, 373.416, 373.418, 373.426, 373.461 FS. HistoryNew 9-25-91, Amended 3-21-93, 10-3-95, 3-7-03,________.
40C-42.091 Publications Incorporated by Reference.
(1) The Governing Board adopts by reference Part I Policy and Procedures, Part II, Criteria for Evaluation, and Part III Operation and Maintenance, of the document entitled Applicants Handbook: Regulation of Stormwater Management Systems, Chapter 40C-42, F.A.C., effective 2-1-05.
(2) through (3) No change.
Specific Authority 369.318, 120.54(8), 373.044, 373.113, 373.118, 373.406, 373.414, 373.418 F.S. Law Implemented 369.318, 373.109, 373.117, 373.118, 373.406, 373.413, 373.414, 373.415, 373.416, 373.418, 373.419, 373.423, 373.426, 373.461, 403.0877, 403.813. History--New 4-11-94, Amended 7-20-95, 10-3-95, 1-11-99, 10-11-01, 4-10-02, 2-1-05,________.
40C-42.900 Forms and Instructions.
The following forms and instructions incorporated by reference have been approved the Governing Board and are available upon request from:
Department of Resource Management
St. Johns River Water Management District
(1) Joint Application For Environmental Resource Permit/Authorization to Use State Lands/Federal Dredge and Fill Permit , form number 40C-4.900(1), revised 2-1-05 adopted (Effective date) 10-3-95.
(2) through (6) No change.
Specific Authority 373.044, 373.113, 373.118, 373.406, 373.414, 373.418 FS. Law Implemented 369.318, 373.085, 373.116, 373.117, 373.118, 373.406, 373.413, 373.414, 373.415, 373.416, 373.418, 373.426, 373.461, 403.0877 FS. HistoryNew 5-30-90. Amended 9-25-91, 3-21-93, 2-27-94, 10-3-95, 10-11-01, 2-1-05,________.
APPLICANTS HANDBOOK SECTION:
3.3 Permit Thresholds
3.3.1 New Stormwater Management Systems
A standard general or individual environmental resource stormwater permit is required under this chapter for construction (including operation and maintenance) of a stormwater management system which serves a project that exceeds any of the following thresholds:
(a) No change.
(b) Construction of 9,000 5,000 square feet total or more of building area or other impervious surface area not subject to vehicular traffic.
(c) No change.
3.3.2 Existing Stormwater Management Systems
A permit is required under this chapter for alteration, removal, reconstruction, or abandonment of existing stormwater management systems which serve a project which may be expected to result in any of the following:
(a) through (e) No change.
(f) Construction of 9,000 5,000 square feet or more of building area or other impervious surface area not subject to vehicular traffic.
(g) No change.
8.0 Criteria for Evaluation
8.1 through 8.4 No change.
8.5
Chapter 40C-41, F.A.C., establishes additional criteria which are used in reviewing applications for permits in certain hydrologic basins. The three two basins in the District which have additional criteria for chapter 40C-42, F.A.C., are the Sensitive Karst Basin, and the Lake Apopka Hydrologic Basin, and the Wekiva Recharge Protection Basin. The sensitive
11.0 Design Criteria and Guidelines for Retention Systems
11.1 Deion
Retention system is defined as a storage area designed to store a defined quantity of runoff, allowing it to percolate through permeable soils into the shallow ground water aquifer. Stormwater retention works best using a variety of retention systems throughout the project site. Examples of retention systems include:
· Man-made or natural depressional areas where the floor is graded as flat as possible and turf is established to promote infiltration and stabilize the basin slopes (see Figure 11-1)
· Shallow landscaped areas designed to store stormwater
· Vegetated swales with swale blocks or raised inlets
· Pervious concrete with continuous curb
Soil permeability and water table conditions must be such that the retention system can percolate the desired runoff volume within a specified time following a storm event. After drawdown has been completed, the basin does not hold any water, thus the system is normally "dry." Unlike detention basins, the treatment volume for retention systems is not discharged to surface waters.
Retention systems provide excellent removal of stormwater pollutants. Substantial amounts of suspended solids, oxygen demanding materials, heavy metals, bacteria, some varieties of pesticides and nutrients such as phosphorus are removed as runoff percolates through the vegetation and soil profile.
Retention systems should not be located in close proximity to drinking water supply wells. Chapter 62-55522, F.A.C., requires stormwater treatment facilities to be at least 100 feet from any public supply well. Chapter 40C-41, F.A.C., provides additional design features for systems constructed in Sensitive Karst Areas of the District where the drinking water aquifer is close to the land surface (see section 9.11).
Besides pollution control, retention systems can be utilized to promote the recharge of ground water to prevent saltwater intrusion in coastal areas or to maintain groundwater levels in aquifer recharge areas. Chapter 40C-41, F.A.C., contains recharge criteria for the
There are several design and performance criteria specific to retention systems which are described below.
11.2 through 11.6 No change.
13.0 Exfiltration Trench Design and Performance Criteria
13.1 Deion
Exfiltration trench is a subsurface system consisting of a conduit such as perforated pipe surrounded by natural or artificial aggregate which temporarily stores and infiltrates stormwater runoff (Figure 13-1). Stormwater passes through the perforated pipe and infiltrates through the trench walls and bottom into the shallow groundwater aquifer. The perforated pipe increases the storage available in the trench and helps promote infiltration by making delivery of the runoff more effective and evenly distributed over the length of the system (Livingston et al. 1988). Generally, exfiltration trench systems are utilized where space is limited and/or land costs are high (i.e., downtown urban areas).
Soil permeability and water table conditions must be such that the trench system can percolate the required stormwater runoff treatment volume within a specified time following a storm event. The trench system is returned to a normally "dry" condition when drawdown of the treatment volume is completed. Like retention basins, the treatment volume in exfiltration trench systems is not discharged to surface waters. Thus, exfiltration is considered a type of retention system.
Like other types of retention systems, exfiltration trench systems provide excellent removal of stormwater pollutants. Substantial amounts of suspended solids, oxygen demanding materials, heavy metals, bacteria, some varieties of pesticides and nutrients such as phosphorus are removed as runoff percolates through the soil profile. Exfiltration trench systems should not be located in close proximity to drinking water supply wells. Chapter 62-55522, F.A.C., requires stormwater treatment systems to be at least 100 feet from any public supply well. Chapter 40C-41, F.A.C., provides additional design features for systems constructed in Sensitive Karst Areas of the District where the drinking water aquifer is close to the land surface (see section 9.11).
Besides pollution control, exfiltration trench systems can be utilized to promote the recharge of ground water and to prevent saltwater intrusion in coastal areas, or to maintain groundwater levels in aquifer recharge areas. Chapter 40C-41, F.A.C., contains recharge criteria for the
The operational life of an exfiltration trench is believed to be short (possibly 5 to 10 years) for most exfiltration systems. Sediment accumulation and clogging by fines can reduce the life of an exfiltration trench (Wanielista et al. 1991). Total replacement of the trench may be the only possible means of restoring the treatment capacity and recovery of the system. Periodic replacement of the trench should be considered routine operational maintenance when selecting this management practice.
13.2 through 13.11 No change.
14.0 Wet Detention Design and Performance Criteria
14.1 and 14.2 No change.
14.3 Recovery Time
The outfall structure should be designed to drawdown one-half the required treatment volume within 24 and 30 between 48 and 60 hours following a storm event, but no more than one-half of this volume will be discharged within the first 24 hours.
14.4 The outlet structure generally includes a drawdown device (such as an orifice, V or square notch weir) set to establish a normal water control evaluation and slowly release the treatment volume (see Figures 14-2 and 14-3 for schematics). The design of the outfall structure must also accommodate the passage of groundwater baseflows and flows from upstream stormwater management systems (see Figure 14-4).
The control elevation should be set at or above the design tailwater elevation so the pond can effectively recover the treatment storage. Also, drawdown devices smaller than 6 square 3 inches of cross-section area that is 2 inches wide minimum width or less than 20 degrees for V notches shall include a device to eliminate clogging. Examples of such devices include baffles, grates, screens, and pipe elbows.
14.5 through 14.14 No change.
15.0 Design Criteria and Guidelines for Swale Systems
15.1 Deion
Swales are a man-made or natural system shaped or graded to required dimensions and designed for the conveyance and rapid infiltration of stormwater runoff. Swales are designed to infiltrate a defined quantity of runoff through the permeable soils of the swale floor and side slopes into the shallow ground water aquifer (Figure 15-1). Turf is established to promote infiltration and stabilize the side slopes. Soil permeability and water table conditions must be such that the swale can percolate the desired runoff volume from the 3-year, 1-hour storm event. The swale holds water only during and immediately after a storm event, thus the system is normally "dry." Unlike retention basins, swales are "open" conveyance systems. This means there are no physical barriers such as berms or check-dams to impound the runoff in the swale prior to discharge to the receiving water.
Swales provide excellent removal of stormwater pollutants. Substantial amounts of suspended solids, oxygen demanding materials, heavy metals, bacteria, some varieties of pesticides and nutrients such as phosphorus are removed as runoff percolates through the vegetation and soil profile. Swale systems should not be located in close proximity to drinking water supply wells. As required by chapter 62-55522, F.A.C., stormwater treatment facilities must be at least 100 feet from any public supply well. Additional design criteria are established for swale systems constructed in Karst Sensitive Areas of the District where the drinking water aquifer is close to the land surface (see section 9.11).
Besides pollution control, swale systems can be utilized to promote the recharge of groundwater to prevent saltwater intrusion in coastal areas, and to maintain ground water levels in aquifer recharge areas. Swales can be incorporated into the design of a stormwater management system to meet the recharge criteria for the Wekiva Recharge Protection Basin and the Tomoka River and Spruce Creek Hydrologic Basins (see sections 11.3.1 and 11.5.1 of the Applicant's Handbook: Management and Storage of Surface Waters) or the runoff volume criteria for projects requiring permits under chapters 40C-4 or 40C-40, F.A.C., which discharge to land-locked lakes (see section 10.4 of the Applicant's Handbook: Management and Storage of Surface Waters).
Swales can also be utilized to provide pre-treatment of runoff prior to its release to another treatment BMP such as wet detention (see section 14.11) or wetlands stormwater management systems (see section 16.4). Pre-treatment reduces the pollutant loading to the downstream treatment system, increases the pollutant efficiency of the overall stormwater management system, and reduces maintenance. In some cases, pre-treatment may be used to meet the additional treatment criteria for discharges to sensitive receiving waters (Class I, Class II, and OFWs). For developments where the appearance of the downstream system (i.e, wet detention lake) is important, pre-treatment can reduce the probability of algal blooms occurring and slows the eutrophication process.
The design and performance criteria specific to swale systems are described in the following sections.
15.2 through 15.5 No change.
