The EPA today announced a proposal that targets smog-forming air pollution transported across state lines. The agency says it will reduce summertime emissions of oxides of nitrogen (NOx) from power plants that contribute to downwind ozone problems in the eastern half of the US.
The proposed updates to the agency’s Cross-State Air Pollution Rule (CSAPR) address interstate air quality impacts for the 2008 ozone air quality standards.
The Clean Air Act’s “good neighbor” provision requires states — or, as a backstop, the EPA — to address interstate transport of air pollution that affects the ability of downwind states to attain and maintain clean air standards. Under the “good neighbor” provision, states develop state implementation plans while the EPA plays a backstop role by issuing federal implementation plans (FIPs) if a state fails to submit an approvable plan.
Today’s proposal provides the FIP that would apply if the EPA’s backstop obligation is triggered. States may choose to have their emissions sources controlled by the FIP rather than developing their own plan.
Specifically, the proposed updates identify cuts in power plant NOx emissions in 23 states in the eastern half of the US that contribute significantly to downwind ozone air quality problems and can be achieved using existing, proven and cost-effective control technologies. The proposed cuts in NOx emissions would lead to significant improvements in air quality for the 2017 ozone season, the agency says.
The EPA is also proposing to adopt FIPs for each of the 23 states in the event that a state does not submit an approvable SIP.
The agency estimates that the proposed CSAPR Update Rule will reduce NOx emissions from power plants in the East by 85,000 tons in 2017 compared to projections without the rule. Due to this proposed rule and other changes already underway in the power sector, ozone season NOX emission will be 150,000 tons lower in 2017 than in 2014, a reduction of more than 30 percent.
By reducing ozone exposure, the proposal would provide annual benefits of $700 million to $1.2 billion in 2017, outweighing the estimated costs of $93 million, the EPA says. The agency also says the proposal will provide climate-related co-benefits, estimated at around $23 million per year.
The CSAPR, which was finalized in 2011, was designed to help states meet the 1997 ozone standards. Now that the CSAPR approach to define upwind state obligations under the “good neighbor provision” has been affirmed by the Supreme Court, the EPA is applying this approach to the 2008 ozone NAAQS to help states address transported ozone pollution problems under the strengthened standards.
This proposal also responds to the July 2015 decision of the Court of Appeals for the DC Circuit and addresses the court’s concerns regarding ozone season NOx emissions budgets for 11 states.
Last month the EPA issued tighter smog standards, limiting ground-level ozone to 70 parts per billion from 75 ppb.
Photo Credit: smog via Shutterstock
