EPA Withdraws Construction Sites Numeric ELGs

In the latest on storm water regulation, the U.S. Environmental Protection Agency (EPA) has withdrawn its proposed rule that would have revised the enforceable numeric effluent limits for runoff from construction sites, according to Wendel, Rosen, Black & Dean LLP.  The numeric limits were established for turbidity in effluent limitation guidelines (ELG) adopted by the EPA in December 2009.  Once established for specific industrial sectors, ELGs must be incorporated in National Pollutant Discharge Elimination System (NPDES) permits issued to point-source dischargers.

This regulatory matter has been a tortuous journey for the EPA, one that may not reach a conclusion any time soon.  Following a lawsuit filed in 1989 by the Natural Resources Defense Counsel (NRDC) alleging that EPA had failed to meet its statutory obligation relative to discharges from construction and development, the EPA identified that sector as an industrial point source category for further rulemaking under Clean Water Act section 304(m).  The EPA then solicited comments in 2002 on a range of options to address construction storm runoff.  In 2004, the EPA decided not to promulgate ELGs, drawing further litigation from NRDC, which did not end favorably for the EPA.  A California District Court held in 2006 that once EPA lists an industrial point source category under section 304(m), it has a mandatory duty to promulgate ELGs and New Source Performance Standards (NSPS).  Meeting the court’s deadlines, the EPA proposed ELGs and NSPS in November 2008, and adopted them in December 2009.  Construction storm water permits adopted after Feb. 1, 2009 were required to incorporate the numeric effluent limits contained in the ELG.

In November 2010, the EPA stayed the numeric turbidity limit in order to review its calculations used to set the limit. As a result, it had to extend the expiration date of the 2008 permit from June 20, 2011 to Feb. 15, 2012 in order to allow time to incorporate the new numeric limitations in the new construction permit.  Most recently, on Aug. 12, 2011, the EPA withdrew its proposal in order to gather more data, a move that will extend the period of uncertainty for those subject to the federal construction storm water permit.

The EPA’s 2009 ELG set a turbidity limit of 280 nephelometric turbidity units (NTU) for construction runoff.  California’s new Construction General Permit (CGP), adopted shortly before the EPA adopted its ELG, set a numeric turbidity limit of 250 NTU.  The CGP timing conveniently relieved the State Water Resources Control Board of using EPA’s numeric limit until the following permit cycle.  While it may have been the EPA’s proposed 13 NTU limit that propelled the state to adopt the CGP before EPA adopted the ELG, California’s CGP is not subject to the EPA’s shifting rulemaking.

Source: Wendel, Rosen, Black & Dean LLP