The U.S. Environmental Protection Agency on Friday issued a proposal to reduce emissions of toxic air pollutants like mercury, lead, acid gases, and cancer-causing dioxins and furans from facilities that burn sewage sludge. Sewage sludge incinerators (SSIs), which are typically used to burn semi-solid wastes collected during wastewater treatment, are the sixth largest source of mercury pollution in the U.S.

“Sewage sludge is even dirtier than the name sounds,” said Earthjustice attorney James Pew. “It’s full of dangerous substances like heavy metals and toxic industrial chemicals that accumulate in wastewater. When sewage sludge is burned in an incinerator, mercury, lead, dioxins and other highly toxic chemicals are released into neighboring communities, where they foul the local environment and threaten residents’ health.”

The EPA’s proposed rule responds to a court order won by Earthjustice on behalf of Sierra Club and other environmental groups in 2007, in which a federal court rejected the Bush administration’s attempt to avoid regulating incinerators’ toxic emissions. The court’s decision confirmed that the Clean Air Act requires protective emission standards for all facilities that burn any solid waste.

In its proposal, the EPA now states its intention to regulate SSIs under protective Clean Air Act rules that govern waste burning. The standards themselves, however, are far less protective than the Clean Air Act requires. Among other things, the EPA set especially weak standards for the dirtiest and most obsolete facilities.

“Communities living near one of the 218 sewage sludge incinerators operating in the U.S. have been suffering from toxic air for far too long,” said Jane Williams, Chair of the Sierra Club’s Air Toxics Task Force. “We’re happy that the EPA is finally addressing this toxic problem, but the agency needs to give Americans the protection that Congress guaranteed, not watered down standards that will allow the worst polluters to keep making people sick.”