What You Need to Know About the EPA's New Pollution Rules

Plumes of water vapor emit from the coal-fired Tennessee Valley Authority Paradise Fossil Plant in Kentucky, on Aug. 13, 2013 Photograph by Luke Sharrett/Bloomberg

On Monday the Environmental Protection Agency will release new rules aimed at reducing carbon emissions from existing power plants. President Obama is widely expected to announce the rules himself, which will amount to the most aggressive action taken by a president to address climate change.

Here’s what you need to know:

1. Congress is left out. The rules coming Monday will be the culmination of a five-year effort by the Obama Administration to cut carbon emissions. The president’s preferred method was to go through Congress, but that fell apart in 2010 when the much fought-over cap-and-trade bill failed in the Senate. Once Republicans took back control of the House, further attempts at legislation to curb pollution were no longer an option.

2. The president and the EPA have the power to do this. The agency has the backing of the Clean Air Act and the U.S. Supreme Court. Buried in the 1970 law signed by President Nixon is a three-paragraph clause known as 111(d). Read it here. It stipulates that the EPA is obligated to regulate sources of pollution that “may endanger public health or welfare.” For 30 years, that mostly pertained to emissions from such things as aluminum and fertilizer plants, as well as mercury and other toxins from power plants. But in 2007 the Supreme Court ruled that the EPA must set standards for carbon emissions if the agency deemed them harmful to public health, which in 2009 it did.

3. It’s not clear how much emissions will have to be cut. On Wednesday, the New York Times reported that Obama will seek to reduce carbon emissions from coal plants by 20 percent. Friday afternoon, Bloomberg News reported that the rules may take a two-tiered approach that phases in reductions gradually over the first five years, eventually mandating cuts of as much as 25 percent within 15 years.

4. This is about coal. Although the rules will pertain to all existing power plants, the real target is coal plants. Utilities have spent billions of dollars in the past decade cleaning pollutants out of coal plant emissions, by bolting scrubbers onto smokestacks, for example. Those were aimed at removing mercury and other toxins to comply with other clean air standards known as MATS. But there’s no way to scrub carbon from a coal plant’s emissions. That means either utilities will have to dial back their reliance on coal plants, which account for about 40 percent of all U.S. power generation, or they’ll have to come up with carbon-capture technologies that bury emissions in the ground. Considering the one carbon-capture plant that’s being built in the U.S. is massively over budget and widely considered not ready for commercial use, it seems likely that the new rules will significantly erode coal’s share of power generation down the road.

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