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20 Years in the Making - National Standards for Mercury Pollution from Power Plants

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Today, after 2 decades of controversy, the U.S. EPA released a final version of its new standards to limit toxic emissions from power plants. Under the Mercury and Air Toxics Standards (MATS) and the New Source Performance Standards (NSPS) for fossil-fired power plants, the EPA will be able to regulate the emission of:

  1. Heavy metals – including mercury*, arsenic, chromium, and nickel

  2. Acid gases including hydrochloric acid and hydrofluoric acid

  3. Particulate matter

  4. Sulfur dioxide (SO2)

  5. Nitrogen oxides (NOx)

As a result of this rule, the EPA estimates that 17,000 premature deaths and hundreds of thousands of illnesses will be prevented each year. In a statement issued by the EPA today, Administrator Lisa Jackson stated that:


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By cutting emissions that are linked to developmental disorders and respiratory illnesses like asthma, these standards represent a major victory for clean air and public health– and especially for the health of our children. The Mercury and Air Toxics Standards will protect millions of families and children from harmful and costly air pollution and provide the American people with health benefits that far outweigh the costs of compliance.”

The EPA also released a brief video that outlines the motivations behind the new set of standards:

Opponents of these standards have voiced concerns regarding its impact on the nation’s older coal-fired power plants, which would require costly retrofits in order to meet the new emissions standards. In response to these concerns, a Presidential Memorandum was also issued today. In this memo, President Obama reiterated findings by the EPA and DOE, stating that:

“The EPA has concluded that four years should generally be sufficient to install the necessary emission control equipment, and DOE has issues analysis consistent with that conclusion. While more time is generally not expected to be needed, the Clear Air Act provides the EPA with flexibility to bring [power plants] into compliance over the course of an additional year, should unusual circumstances arise that warrant such flexibility”

The President also spoke about the standards in a video posted on the White House blog, where he encouraged the nation to celebrate this accomplishment.

Senate Republicans, led by Senator Jim Inhofe (R-OK), have already announced plans to introduce a “disapproval resolution” under the Congressional Review Act. But, for now, this action seems like a stall tactic instead of a legitimate protest regarding the legality of the new standards. And, it appears that the nation is on track to significantly reduce its emissions of many toxic materials by 2016.

*Half of the mercury emissions in the United States currently come from the nation’s fossil-fuel power plants