Nearly five years after the U.S. Supreme Court directed the U.S. Environmental Protection Agency (EPA) to determine whether carbon dioxide should be regulated as a "pollutant" under the Clean Air Act, the agency finally issued a proposed standard for carbon emissions from newly constructed power plants.

What's in the Standard

The Carbon Pollution Standard for New Power Plants, which was issued as a proposed rule on March 27, directs permits for new power plants to be issued only if a facility will emit no more than 1,000 pounds of carbon dioxide per megawatt-hour of electricity generated. The rule applies only to new, not existing power plants, and does not specify any particular fuel or technology.

The "average" American power plant emits somewhere between 800 and 850 pounds of carbon dioxide per megawatt-hour – "traditional" coal-fired power plants, however, emit more than twice this amount. Observers have suggested that the rule amounts to a ban on coal-fired power plants without carbon sequestration technology. As George Peridas of the Natural Resources Defense Council has pointed out, carbon sequestration is now a technological and regulatory reality – in fact, coal plants that would meet the new standard are already proposed in Mississippi and Texas.

How We Got to a Proposed Rule

The Carbon Pollution Standard was issued as a proposed rule under Section 111 of the Clean Air Act. The EPA will receive public comments on the rule for 60 days and also plans to hold public hearings. This is, however, certainly not the first opportunity for public input on the rule.

In 2006, the EPA issued air pollution standards that did not treat carbon dioxide as a pollutant. Based on arguments by the state of Massachusetts and others, the U.S. Supreme Court found in April 2007 that carbon dioxide, and greenhouse gases generally, should be treated as pollutants. In 2009, the EPA determined that carbon pollution threatens human health and welfare, which should have triggered regulation under the Clean Air Act. However, the EPA did not move forward with regulations for carbon emissions. Under threat of another lawsuit, the EPA agreed in December 2010 to issue the rule for power plants.

Under the settlement agreement, the rule was originally due in July 2011. Throughout 2011, the EPA held several "listening sessions" and collected written comments from stakeholders. In September 2011, the EPA publicly acknowledged that the rule was being delayed, but did not offer a new target completion date.

What Will Happen Next?

Ahead of the March announcement that a proposed rule would be issued in short order, it was unclear exactly when, how, and in what form the Obama administration had intended to proceed with the rule. Because other EPA rules had been delayed over the past several months, environmental and public interest advocates protested sharply.

For example, Earthjustice Senior Legislative Representative Sarah Saylor said, "The Obama administration and the EPA owe it to the people of this nation to put these pollution safeguards promptly in place. We hope President Obama and Administrator Jackson follow through on their promises and move swiftly to issue these necessary pollution protections."

Although the EPA has stated that the public comment period will last for 60 days, the agency has not yet issued a schedule for the public hearings or projected when the rule will be final. Even though it is just at the proposed stage, the rule has come under harsh criticism from energy and coal interests. Under pressure from similar groups in September 2011, President Obama directed the EPA to withdraw a final rule on the national air quality standard for ozone.

Uncertainty remains as to whether, how, and when the carbon pollution standards for power plants will be finalized, but it seems clear that those decisions will involve political calculations. This is unfortunate, as we know delays cost lives. The public should be protected from unchecked carbon pollution as soon as possible.