Jackson and other administration officials said the new rule was based on a rigorous scientific review. Only 66 of more than 3,000 U.S. counties would fail to meet the proposed standard, which takes effect early next year.
The EPA said it would start designating counties that fail to meet the new soot standards as soon as December 2014, but would give states up to five years to meet the revised standard.
All but seven counties in the United States — all in California — are projected to meet the new standard by 2020 with no additional actions needed beyond compliance with existing and pending rules set by the EPA, EPA officials said. The counties are Imperial, Kern, Los Angeles, Merced, Riverside, San Bernardino and Tulare.
Jackson and other officials said they will work with states and counties to ensure they can meet the new standards without penalties, including loss of federal transportation money.
The Obama administration had sought to delay the new soot standards until after the November election, but a federal judge ordered officials to act sooner, and the administration released a proposed rule in June.
EPA soot rule: www.epa.gov/pm/actions.html
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