S. C. Stormwater Management and Sediment Reduction Regulations Dwayne E. Creel, P.E. Manager, SCDHEC Stormwater, Agricultural and Dams and Reservoir Safety Permitting Section

What Regulations Apply to Land Disturbing Activities? S. C. Stormwater Management and Sediment Reduction Act of 1991, R NPDES General Permit for Construction Activities, SCR S. C. Pollution Control Act

Stormwater Permitting Requirements All activities that disturb more than 2 acres of land are required to obtain a state land disturbance permit All activities that disturb 2 acres or less are required to submit an application for permit exemption along with a set of site plans Federal NPDES General Permit coverage required for all activities that disturb one or more acres (this includes activities that are exempt from the State permitting requirements)

Permitting Fees State stormwater permit fees for sites disturbing more than 2 acres or projects that are less than 2 acres but are part of a larger common plan: $100/disturbed acre up to a maximum of $2000 NPDES General Permit fees: $125 (If the project is exempt from the State permitting requirement, but requires a review for NPDES coverage, then a $100/disturbed acre fee also applies)

Projects Exempt from R Agricultural activities Forestry activities Activities undertaken by persons regulated by the SC Mining Act Construction of single family residences that are not part of a larger common plan for development Repair and maintenance of railroad facilities Certain activities undertaken by persons providing gas, electrification, or communication services which are subject to the jurisdiction of the SC Public Service Commission

State Permit Requirements Plans must be prepared by a registered engineer, landscape architect, or tier B land surveyor Plans must show how sediment and erosion control will be addressed Best Management Practices (BMPs) must be identified on the plans and installed accordingly Approved plans must be kept on-site at all times BMPs should be inspected at least once every 7 days and after each rainfall event greater than 0.5 inches

State Permit Requirements Regulations require that post-developed stormwater runoff rates not exceed pre-developed runoff rates for sites that disturb more than 2 acres Detention waivers can be granted on a case-by- case basis with proper justification If 10 or more disturbed acres drain to a single point, then sediment calculations must be submitted showing a trapping efficiency of at least 80%

State Permit Requirements Permanent water quality measures are required when 5 or more impervious acres are created For a stormwater pond without a permanent pool, the first 1 of runoff over the entire site must be captured in the pond and released over a 24 hour period For a stormwater pond with a permanent pool, only the first 1/2 of runoff must be captured

State Permit Requirements If water quality is required, but permanent detention is not, then additional BMPs must be used to meet water quality requirements, such as: - inline treatment devices (Stormceptor, Vortechnics, Baysaver, etc.) - grassed swales - buffer strips - drop inlet filter devices (filter socks, bags, etc.) - bioretention areas

State Permit Requirements If a detention or retention pond is being constructed, a pond maintenance plan along with a letter from the owner accepting ownership and maintenance responsibility must also be included with the submittal Ease of maintenance must be considered in the pond design Examples of maintenance items: inspecting the pond once a month mowing grass and weeds when necessary regrading and restablizing, if necessary, etc.

What Should be Shown on the Plans Site location map Legend Plan preparers registration seal (signed) North arrow and scale Existing and proposed contours Limits of disturbance Delineation of wetlands and/or waters of the State Construction sequence of activities

What Should be Shown on the Plans Location of all temporary and permanent control devices Grassing and seeding schedule Details for all sediment and erosion control devices Statement indicating that if water is encountered while trenching, it should be filtered to remove any sediments before being pumped back into a creek or wetland area (for utility projects) Statement recommending covering and temporary seeding at the end of each day (for utility projects)

Additional Items to be Submitted Permit application form Permit application fees Project narrative Stormwater calculations Pre and postdeveloped drainage area maps Copy of a USGS topo map showing the site Floodway/FEMA Flood maps, if necessary Any other information necessary to review the permit application

What Should Be Done During Construciton Properly install and maintain BMPs Perform weekly inspections of BMPs and make any necessary repairs Minimize the potential for offsite impacts Try to phase construction in order to reduce the amount of land disturbed at one time Disturbed areas should be grassed within 14 days of the completion of construction on that portion of the site

Federal NPDES Permit Requirements All projects that disturb 1 acre or more and any project in the coastal counties that is within 1/2 mile of a receiving waterbody are required to obtain coverage under NPDES General Permit SCR A Stormwater Pollution Prevention Plan must be prepared for the land disturbing activity If an application is made under the State program, that serves as the Notice of Intent for coverage under the NPDES General Permit as well

Federal NPDES Permit Requirements All contractors and subcontractors whose work at the site involves land disturbance that may affect stormwater and sediment control must sign a copy of a certification statement accepting co-permittee status (Co-permittee Agreement) Must keep a copy of the plans on site at all times Keep a record of all inspections and maintenance activities

Status of the NPDES General Permit The existing GP expired Jan. 31, 2003 The expired GP continues in effect until a new GP is issued Draft of the proposed GP public noticed in December 2003 In the process of responding to comments received during the public notice period GP expected to be issued within the next 3-4 months

Proposed Changes to the NPDES General Permit Owners/operators of construction activities that disturb 10 or more acres must submit monthly reports to DHEC summarizing the inspections and compliance status Inspection frequency has been modified to allow more flexibility: –Inspect every 7 days or –Inspect every 14 days and within 24 hours after a storm event of 0.5 inches or greater

Proposed Changes to the NPDES General Permit Site inspections must be performed by one of the following: - preparer of the SWPPP or someone who works directly for the plan preparer - someone with a registration equivalent to that of the plan preparer or someone who works directly for that equivalent individual - a Certified Sediment and Erosion Control Inspector (must have been certified through a DHEC approved training course, passed an examination, and have adequate work experience in sediment and erosion control)

Results of Permit Non-Compliance Issuance of a cease and desist order State fine of up to $1000 per day per violation NPDES fines: Civil penalties of up to $10,000 per day per violation Criminal penalties of up to $25,000 per day per violation

DHEC Stormwater Webpage Application form Plan review checklist Soils data Co-permittee Agreement Plan reviewer information Permit status Stormwater Management Handbook (rev. 8/02) Regulations

Contact Information Dwayne Creel, P.E. SCDHEC Stormwater Permitting Section 2600 Bull Street Columbia, SC (803)