In response to a court order, the U.S. Environmental Protection Agency on Friday, June 15, proposed updates to its national air quality standards for harmful fine particle pollution, including soot – known as PM2.5. EPA’s proposal would strengthen the annual health standard for harmful fine particle pollution to a level within a range of 13 micrograms per cubic meter to 12 micrograms per cubic meter; the current annual standard is 15 micrograms per cubic meter.
EPA said the proposed changes, which were consistent with the advice from the agency’s independent science advisers, are based on an extensive body of scientific evidence that includes thousands of studies – including many large studies that show negative health impacts at lower levels than previously understood. By proposing a range, the agency will collect input from the public as well as a number of stakeholders, including industry and public health groups, to help determine the most appropriate final standard.
EPA said that because of recent Clean Air Act rules that have and will dramatically cut pollution, 99 percent of U.S. counties are projected to meet the proposed standards without undertaking any further actions to reduce emissions, meaning the standards will have major economic benefits with comparatively low costs.
EPA said that depending on the final level of the standard, estimated benefits will range from $88 million a year, with estimated costs of implementation as low as $2.9 million, to $5.9 billion in annual benefits with a cost of $69 million – a return ranging from $30 to $86 for every dollar invested in pollution control.
The Clean Air Act requires EPA to review its standards for particle pollution every five years to determine whether the standards should be revised. The law requires the agency to ensure the standards are “requisite to protect public health with an adequate margin of safety” and “requisite to protect the public welfare.”
A federal court ordered EPA sign the proposed particle pollution standards by Thursday, June 14, because the agency did not meet its five-year legal deadline for reviewing the standards. The administration had sought to delay the new soot standards until after the November elections, but a federal judge ordered EPA to act sooner after 11 states filed a lawsuit seeking a decision this year.
EPA spokesperson Gina McCarthy said all but six U.S. counties would meet the proposed standard by 2020 with no additional actions needed beyond compliance with existing and pending agency rules. Those counties are San Bernardino and Riverside counties in Calif.; Santa Cruz County, Ariz.; Wayne County, Mich.; Jefferson County, Ala.; and Lincoln County, Mont. All six face “unique challenges” and will receive individual attention from EPA, McCarthy said.
EPA will accept public comment for 63 days after the proposed standards are published in the Federal Register. The agency will hold two public hearings; one in Sacramento, Calif., and one in Philadelphia; details on the hearings will be announced shortly. EPA said it will issue the final standards by Dec. 14.
Advancements in clean diesel technology over the past 10 years in conjunction with new research and development in all modes of diesel engines will play a major role in helping meet the updated standards, said Allen Schaeffer, executive director of the Diesel Technology Forum.
“For the last decade, diesel technology has undergone a fundamental transformation to near-zero emissions based on ultra-low-sulfur diesel fuel, advanced clean-burning engines and new emissions control technology,” Schaeffer said. “These advancements have occurred across the board – from the smallest industrial engine to the clean diesel cars, commercial trucks, off-road machines and equipment, marine vessels and locomotives. As a result , diesel engine, equipment and vehicle manufacturers have already made tremendous progress in reducing particulate matter emissions, and today diesel is only a small portion of the PM emissions inventory – less than six percent.”