On Nov. 16, the U.S. Environmental Protection Agency (EPA) sent the Office of Management and Budget revised construction and development effluent limitation guidelines (ELG). The agency withdrew numeric turbidity limits proposed in 2009. These new guidelines are based on new treatment performance data and will set the first numeric limits for stormwater runoff.
The numeric limits will replace the technology-based ELG limits currently used in EPA’s construction general permit. The agency extended the expiration date for its current general permit to Feb. 15, 2012, to provide time to revise the ELG and offer a public comment period. In July, WEF gathered comments expressing concern that a nationally applied numeric standard would be problematic because of differences in local conditions, such as terrain, soil, vegetation, precipitation, and other factors.