Office of Water

Construction & Development Effluent Guidelines

December, 2009

Jesse W. PrittsUSEPA

Office of Water

Office of WaterPage 2

Overview

EPA promulgated effluent limitations guidelines and new source performance standards for discharges from construction and development (C&D) sites on December 1, 2009.

New rule requires all construction sites subject to permits to implement erosion and sediment controls and pollution prevention measures

Phase-in requirement for sites to sample stormwater discharges and comply with a numeric effluent limitation (NEL) of 280 nephelometric turbidity units (NTU).– Beginning August 1, 2011 sites disturbing 20+ acres at once

– Beginning February 2, 2014 sites disturbing 10 acres at once

Requirements must be incorporated into state permits (general or individual) whenever permits are re-issued

EPA intends to issue a new CGP in June 2011

Office of WaterPage 5

Existing Benchmarks/Action Levels/Monitoring Requirements

State/Area Monitoring Requirement Benchmark/Action Level

California Monitoring of discharges from every storm event of 0.5 inch or more for Risk Level 2 (pH and turbidity) and Risk Level 3 (ph, turbidity and SSC) sites

250 NTU

(500 NTU NEL for Risk Level 3 sites)

Oregon

Discharges to 303(d) listed waters or TMDL for sediment or turbidity

Weekly for turbidity or transparency 160 NTU

Washington Weekly for turbidity and pH 25 NTU

250 NTU

Vermont

Moderate risk sites

Visual inspection after every event producing runoff – if visible discharge of sediment is present, implement additional BMPs. If discharge continues, sampling is required.

25 NTU

Georgia Monitoring of receiving waters or outfalls for first storm of 0.5 inch or greater and again 90 days later or after completion of mass grading

Varies based on site size and watershed size (20 – 750 NTU)

Office of WaterPage 7

Erosion and Sediment Control Requirements

Control stormwater volume and velocity within the site to minimize soil erosion;

Control stormwater discharges to minimize erosion at outlets and downstream channel and streambank erosion;

Minimize the amount of soil exposed during construction activity;

Minimize the disturbance of steep slopes; Design, install and maintain erosion and

sediment controls considering factors such as precipitation and soil characteristics;

Provide and maintain natural buffers around surface waters, direct stormwater to vegetated areas to increase sediment removal and maximize stormwater infiltration, unless infeasible; and

Minimize soil compaction and, unless infeasible, preserve topsoil.

Office of WaterPage 8

Soil Stabilization and Dewatering Requirements

Initiate stabilization of disturbed areas immediately whenever any clearing, grading, excavating or other earth disturbing activities have permanently ceased,

Initiate stabilization immediately when earth disturbing activities have temporarily ceased and will not resume for a period exceeding 14 calendar days.

In arid, semiarid, and drought-stricken areas where vegetative stabilization is infeasible, alternative stabilization measures must be employed.

Discharges from dewatering activities, including discharges from dewatering of trenches and excavations are prohibited unless managed by appropriate controls.

Office of WaterPage 9

Pollution Prevention Requirements

Minimize the discharge of pollutants from equipment and vehicle washing, wheel wash water, and other wash waters. Wash waters must be treated in a sediment basin or alternative control that provides equivalent or better treatment prior to discharge;

Minimize the exposure of building materials, building products, construction wastes, trash, landscape materials, fertilizers, pesticides, herbicides, detergents, sanitary waste and other materials present on the site to precipitation and to stormwater;

Minimize the discharge of pollutants from spills and leaks and implement chemical spill and leak prevention and response procedures.

Office of WaterPage 10

Prohibited Discharges

Wastewater from washout of concrete, unless managed by an appropriate control;

Wastewater from washout and cleanout of stucco, paint, form release oils, curing compounds and other construction materials;

Fuels, oils, or other pollutants used in vehicle and equipment operation and maintenance; and

Soaps or solvents used in vehicle and equipment washing.

Office of WaterPage 11

Surface Outlets

When discharging from basins and impoundments, utilize outlet structures that withdraw water from the surface, unless infeasible.

Office of WaterPage 12

Turbidity Limitation and Monitoring

Turbidity limitation of 280 NTUs applies to sites that disturb 10 or more acres of land at one time

– Beginning August 1, 2011 applies to sites with 20+ acres disturbed at one time

– On February 2, 2014 applies to sites with 10+ acres disturbed at one time

Limit is based on polymer-assisted settling, but permittees can use any technology

Limitation is an Daily Maximum Value (not tied to background)

Daily value at each discharge point is calculated by averaging all samples at that point

– Individual samples can be above 280 NTU as long as average is below 280 NTU

Can use zero discharge (such as infiltration, discharge to forested or vegetated buffers)

Permittees can phase land disturbing activities to stay below the disturbed acreage threshold

Office of WaterPage 14

Sampling Requirements

Sampling frequency is up to the permitting authority, but EPA recommends that at least 3 samples per day be collected at each discharge point when a discharge is occurring only during normal working hours

Sampling required at each discrete discharge point (basins, channels, pipes, etc.)

Sampling of sheetflow or diffuse runoff is not required as long as it does not become channelized prior to discharge

Sampling methods are up to the permitting authority, field turbidity meter is sufficient

Limitation does not apply on days with precipitation exceeds the local 2-year, 24-hour storm event

For linear projects, permitting authorities can consider representative sampling, instead of sampling at each discharge point

Office of WaterPage 15

More Information

C&D Web Page

http://www.epa.gov/waterscience/guide/construction/

Jesse Pritts

pritts.jesse@epa.gov

202-566-1038