Construction Storm Water 2013 Update for NPDES Permit #OHC000004

Transcription

1 Construction Storm Water 2013 Update for NPDES Permit #OHC Molly Drinkuth Ohio EPA Division of Surface Water Northeast District Office June 20, 2013

2 Why Regulate Construction Storm Water? Spilled paint Leaking Equipment Oil, Fuel & Other Fluids Sanitary Waste Trash & Debris Concrete Washout

3 What is the National Pollutant Discharge Elimination System (NPDES) permit? Required whenever the larger common plan of development or sale disturbs 1 or more acre Establishes requirements for Sediment and Erosion Control Non-Sediment Pollutant Controls Post-Construction Storm Water Quality Management Requires a Storm Water Pollution Prevention Plan (SWP3) Plan provides details of control measures to be implemented at the permitted site

4 Who Needs a Permit? All operators require NPDES permit coverage Operators are those with control over the site plans or day-to-day operations at the site Developer, general contractor, construction site management company Homebuilder in residential construction Permit coverage must be obtained before starting work at the site

5 How Do I Obtain a Permit? Notice of Intent (NOI) Submitted by developer at least 21 days prior to commencement of construction activity Must include a site vicinity map with boundaries of project area identified and permit fee Co-Permitte NOI Submitted by general contractor and construction management company before they begin work on site No fee Individual Lot NOI Submitted by new operator when a parcel within the development is sold to a different operator Submitted at least 7 days prior to the start of construction on lot Developer must maintain all centralized controls No fee

6 How Do I Obtain a Permit? If you are not an operator but, are a contractor or subcontractor whose work can impact SWP3 implementation You do not need a permit, but Permittee has duty to inform you about SWP3 requirements Must keep signed contractor certifications acknowledging receipt of information Examples available at

7 Does Anyone Review the SWP3? Ohio EPA does not typically review the SWP3 prior to permit issuance Getting a permit does not mean the SWP3 complies with the permit! Within urbanized areas of the state, local government reviews the SWP3 Typically, the SWCD or City Engineer Ohio EPA will review the SWP3 as part of the site inspection must be kept on site Can require changes if plan does not comply with NPDES permit or is ineffective

8 What s New About Permitting? OAC amended in 2010 Construction permit coverage expires 5 years from date on Director s Authorization letter. If the project is not complete, coverage must be renewed every 5 years. Non-Numeric Effluent Limitations (40 CFR ): Erosion & Sediment Controls Soil Stabilization (stabilize sites dormant 14 days) Dewatering (must use sediment removing BMPs) Pollution Prevention Measures Prohibited Discharges (wastewater, fuel, oil, soap) Surface Outlets (skimmers for sediment ponds)

9 For Projects with Coverage Under the Prior Generation NPDES Permit Ohio EPA will notify permittees of previous construction general permits of the renewal If project is not complete, permittees must notify Ohio EPA that they require continued coverage For coverage < 5 years old, the permittee must sign & return notice to OEPA within 90 days & update SWP3 For coverage > 5 years old, the permittee must submit an NOI & check for NOI fee within 90 days & update SWP3 If Ohio EPA is not notified within 90 days for continuation of CGP coverage, the permit will be automatically terminated

10 Non-Numeric Effluent Limitations Erosion & Sediment Controls (Part II.A) Control runoff volume & velocity to minimize erosion Control flow rates & volume to minimize erosion at outlets, downstream channel & streambank erosion Minimize soil exposure during construction Minimize steep slope disturbance Minimize sediment discharges by implementing controls for rainfall amount, intensity, frequency & duration for site soils Provide and maintain a 50-foot undisturbed natural buffer around surface waters of the state Minimize soil compaction and preserve topsoil

11 Non-Numeric Effluent Limitations Soil Stabilization (Part II.B) Temporary Stabilization Type of disturbed area Within 50 feet of stream but not at final grade Disturbed areas dormant for over 14 days but < 1 year Disturbed areas idle for winter Time frame to apply erosion controls Stabilize within 2 days if area is dormant for over 14 days Stabilize within 7 days; stabilize lots > 7 days prior to transfer Prior to onset of winter weather

12 Non-Numeric Effluent Limitations Soil Stabilization (Part II.B) Permanent Stabilization Type of disturbed area Within 50 feet of stream and at final grade Disturbed areas dormant for over 1 year Disturbed areas reaching final grade (> 50 feet of stream) Time frame to apply erosion controls Stabilize within 2 days of reaching final grade Stabilize within 7 days of last disturbance Stabilize within 7 days of reaching final grade

13 Soil Stabilization Area idle for 14 days? Stable if 70% growth density

14 Erosion Control Practices Mulching Rock Check Dam Matting Construction Entrance

15 Non-Numeric Effluent Limitations Dewatering (Part II.C) Dewatering activities are prohibited unless managed by appropriate controls Groundwater is generally clean Keep it clean! Be sure that it does not flow over disturbed soils or other pollutants as it is discharged from the site Trench water is generally sediment-laden Must pass through a sediment pond, filter bag, or be pumped out via a sump pit before discharging Visible sheens should be removed with an absorbent prior to passing through a sediment control

16 Non-Numeric Effluent Limitations Pollution Prevention Measures (Part II.D) Wash waters shall be treated in a sediment basin or equivalent, including waters from equipment/vehicle & wheel washing Options for compliance: Locate washing where drainage is directed to sediment basin, OR Collect wash water in a sediment trap Install a proprietary wash system Broom off instead of washing Keep vehicles on stone or pavement Do not use surfactants!

17 Non-Numeric Effluent Limitations Pollution Prevention Measures (Part II.D) Minimize the exposure of building materials/products, construction wastes, trash, landscape materials, fertilizers, herbicides, detergents, sanitary wastes, etc to storm water Provide a lidded or tarped dumpster Take debris to dumpster regularly Do not open burn! Store materials under cover or indoors

18 Non-Numeric Effluent Limitations Pollution Prevention Measures (Part II.D) Minimize the discharge of pollutants from spills & leaks, implement chemical spill & leak prevention and response procedures Place drums on containment trays away from areas of traffic, or in storage locker Place fuel tanks in dikes (and plug the drain!) As a rule of thumb, the containment area should hold 110% of the largest container Keep spill kit on site near potential spill areas Clean up spills when they occur! Diked, but the drain plug is missing!

19 Non-Numeric Effluent Limitations Prohibited Discharges (Part II.E) Concrete washout wastewater Stucco, paint, form release oils & curing compounds cleanout wastewater Collect and pump to sanitary (with approval) Fuel and oil from vehicle & equipment Place drip pans under vehicles Soaps or solvents used in washing Do not use surfactants! Use dry methods instead of washing

20 Concrete Wash Water

21 Non-Numeric Effluent Limitations Surface Outlets (Part II.F) Sediment settling ponds must be dewatered from the surface unless it s infeasible Provide documentation in your SWP3 if determine infeasible Skimmers are commonly used to do this

22 Sediment Settling Pond Requirements Sediment settling ponds will be required for: Concentrated storm water runoff 10 or more acres of disturbance Runoff exceeding design capacity of silt fence or inlet protection Must be designed to dewater at the pond surface using a skimmer or equivalent device and sized for both a sediment storage zone > 1000 ft 3 /disturbed acre and a dewatering zone > 1800 ft 3 /drainage ac Other sediment pond requirements include: maximum pond depth of 5 feet min 2:1 length to width pond ratio; recommend 4:1 minimum 48-hour drain time if drainage area >5ac

23 Sediment Basin Design

24 How would you modify this pond for sediment control? Replace perforated riser w/skimmer Elevation to store Dewatering Volume Plate off window to top of Dewatering Volume Top of Sediment Storage Volume Attach skimmer at top of Sediment Storage Volume

25 Attach Skimmer to Correct Outlet Temporary Outlet Permanent Outlet Check the SWP3

26 Silt Fence Requirements Before the Storm Maximum drainage area to 100 linear feet of silt fence After the Storm Slope range for the corresponding drainage area 0.5 acres < 2% 0.25 acres > 2% but < 20% acres > 20% but < 50%

27 Field Drain Inlet Protection Inlet Protection Curb Drain Inlet Protection

28 Inspection Requirements Site must be inspected by the permittee Once every 7 days Within 24 hours of a rainfall event 0.5-inch Complete and sign inspection checklist Areas to inspect: Walk the site perimeter and note any areas where sediment is leaving the site Areas where exposed materials are stored Check that all BMPs have been installed as the SWP3 specified, built correctly, are functional and appropriate Areas where construction vehicles access the site Water resources on the site or which flow through the site The MS4 Permit requires separate monthly inspections of sites within the MS4.

29 Maintenance Requirements BMP Sediment barriers & erosion control Sediment ponds Modify SWP3 & replace failing BMPs Install BMPs in SWP3 that were not installed (or provide justification) Repair Timeframe 3 days 10 days 10 days 10 days

30 Administrative Compliance Issues Contractor certifications Maintain signed certifications with the SWP3 Inspection reports Must conduct once every 7 days and within 24 hours of a 0.5-in rainfall Inspection reports to be made available to Ohio EPA or local inspector upon request SWP3 must be kept up-to-date Redline minor changes such as relocation of silt fence Project engineer should make major changes such as modification to sediment pond design and reissue new drawings

31 For More Information Websites Ohio EPA US EPA NEDO Ohio EPA Contacts Cuyahoga, Geauga, Lake & Lorain Dan Bogoevski (330) Medina, Portage, Summit & Wayne Molly Drinkuth (330) Ashtabula, Columbiana, Holmes, Mahoning & Trumbull Chris Moody (330) Carroll & Stark Phil Rhodes (330)