EPA Proposal Limits Mercury Emissions from Cement Plants

The EPA has proposed to significantly reduce mercury emissions from Portland cement kilns. These kilns are the fourth largest source of mercury air emissions in the U.S. and this proposal would set the nation's first limits on mercury emissions from existing cement kilns and would strengthen the limits for new ones. There has already been three times where federal courts have told the EPA to set emission standards to control cement kiln's mercury emissions since the Clinton administration. The EPA finally agreed with them in a fourth case brought by Earthjustice, a non-profit environmental law firm that protects the natural environment. Earthjustice attorny Jim Pew called the proposal "really significant. This is one of the most polluting industries in the country."

The majority of toxic emissions at cement kilns come from the burning of fuels and heating of raw materials. The EPA estimates that by 2013, mercury emissions will be at 11,600 pounds per year, which is a reduction of 81 percent. The agency also estimates that the benefits of the proposed rule will greatly outweigh the costs. "The rule would prevent between 620 and 1,600 deaths, according to the EPA, and produce annual benefits of between $4.4 billion and $11 billion while costing the nation's 100 cement kilns between $222 million and $648 million a year."

Mercury in the air eventually deposits into water, where it changes into a highly toxic form that builds up in fish. Americans are primarily exposed to mercury by eating contaiminated fish. According to a 1991 article in Science News, "it only takes 1/70th of a teaspoon of mercury to contaiminate a 25-acre lake. Over 40 states have warned their citizens to avoid consuming various fish species due to mercury contamination." As time passes, the new EPA regulation will help make both freshwater and coastal marine fish safe to eat. Unfortunately, the new rule will not help decontaminate fish imported from other regions of the earth.

The final proposed rule, Portland Cement Manufacturing: Proposed Amendments to National Air Toxics Emission Standards can be found here.