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New EPA Stormwater Regs Expected to Have Moderate Effect on State

The U.S. Environmental Protection Agency (EPA) recently finalized new stormwater requirements that will impact nearly every construction and development project in the United States. These “Construction and Development Effluent Limitations Guidelines” (C&D ELG) impose an enforceable numeric limit on stormwater discharges from sites disturbing 10 acres or more at any one time require monitoring to ensure compliance with the numeric limit and require nearly all construction sites to implement a range of prescriptive erosion and sediment controls and pollution prevention measures.

AGC of Washington members should keep in mind that Washington State has long had stringent stormwater regulations. Plus Washington State DOE will soon revise its regulations in a manner that will be stricter than the federal EPA rules. AGC members are encouraged to review this Q&A on the federal EPA requirements but also take note of this information from James Tupper of AGC-member firm Tupper Mack Browser PLLC:

“The EPA Effluent Limitation Guidelines (ELGs) for construction activities will have a moderate effect on the new Construction Stormwater General Permit (CSGP) that is currently under development in the State of Washington. In Washington the authority to issue federal water quality permits under the Clean Water Act is delegated to the state Department of Ecology except at federal installations and some Tribal lands. The state permits must implement and be consistent with the ELG for construct activities.

The most significant change proposed to the Washington CSGP consistent with ELG is to impose a maximum daily numeric effluent limitation of 280 NTU for construction sites equal or larger than 10 acres. Ecology is proposing that the new limit be applicable on the effective date of the permit anticipated to be January 1 2011. This is a departure from the ELG which affords a phase in of the limit under which sites 20 acres or larger would have to meet the limit by August 1 2011 and sites 10 acres or larger would have to meet the limit by February 2 2014. Ecology states in the recently released fact sheet for the draft permit that this compliance schedule was not adopted because most contractors in Washington are already familiar with monitoring turbidity and because 99% of the reported monitoring data is below 280 NTU.

Ecology also considered the mandatory best management practices on the ELG and concluded that the current CSGP includes the required BMPs in the ELG. The draft CSGP does add several prohibited discharges that are required under the ELG including: wastewater from washout of concrete; wastewater from washout and cleanout of stucco paint release of oils curing compounds and other construction materials; fuels oils or other pollutants used in vehicle and equipment operation and maintenance; soaps or solvents used in vehicle washing; wheel wash or tire bath wastewater; and discharges from dewatering activities.”

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