Mercury Emissions Cuts Proposed for Sewage Sludge Incinerators
The U.S. Environmental Protection Agency is proposing to cut emissions of mercury, particle pollution and other harmful pollutants from sewage sludge incinerators, the sixth-largest source of mercury air emissions in the United States.
Sewage sludge incinerators are typically located at wastewater treatment facilities. The proposed standards would apply to both multiple hearth and fluidized bed incinerators. Units incinerating sewage sludge at other types of facilities such as commercial, industrial and institutional incinerators will be covered under different air pollution standards. Overall, the proposal would cut mercury emissions from these units by more than 75 percent.
Mercury in the air eventually deposits into water, where it changes into methylmercury, a highly toxic form that builds up in fish. People are primarily exposed to mercury by eating contaminated fish. Because the developing fetus is the most sensitive to the toxic effects of methylmercury, women of childbearing age and children are regarded as the populations of greatest concern.
EPA estimates that the proposal would yield health benefits ranging from $130 million to $320 million in 2015, with annualized costs estimated at approximately $105 million for all currently operating units to comply with the proposal standards.
The agency will take comment on the proposed rule for 30 days after it is published in the Federal Register. The rule will be finalized in 2011 and become effective in 2015.