On December 14, 2012, the Environmental Protection Agency (“EPA”) announced that it is strengthening the annual standard for fine particulate matter (PM2.5) from 15 ug/m3 to 12 ug/m3. With the more stringent standard, EPA expects to designate as many as 66 counties to be in violation, 19 of which will be new to the list of counties that do not meet federal PM standards. The official “nonattainment” designations will not be effective until early 2015; states will have a year to submit recommended designations, and EPA will have another year to act on those recommendations. Because PM2.5 levels are expected to continue declining over the next few years in most areas, the final tally of nonattainment counties could be lower.
Once the nonattainment designations become effective in 2015, the new standard could eventually result in new emission reduction requirements, as states develop their plans for reaching 12 ug/m3, due in 2018. However, EPA claims that 99% of the country – all but a few counties in California – are expected to meet the new standard by the deadline (2020) without any new regulatory requirements, due to emission reduction requirements already “on the books.” Even so, EPA claims that its new PM standard will provide the country with over $9 billion in health benefits at a cost of between $53 and $350 million.
Although EPA strengthened the annual standard for PM2.5, it did not change two other particulate matter standards, namely the 35 ug/m3 daily standard for PM2.5 and the 150 ug/m3 annual standard for coarse particulate matter (PM10). EPA also decided not to finalize its proposed “secondary” standard, which had been designed to address the impact of PM levels on visibility, instead of any potential human health effects.
More information on EPA’s new PM2.5 standard can be found here.