The NAM is part of the Fine Particulate Matter Petitioners Group, which filed a petition for review in the D.C. Circuit of a final EPA regulation published in October, 2006, entitled "National Ambient Air Quality Standards for Particulate Matter." This case involves stringent new EPA air quality standards, which industry and agricultural groups say go too far and environmental groups and states say are not strict enough.
The regulation applies both to fine particles (generally smaller than 2.5 micrometers in diameter) and to larger particles (less than 10 micrometers). It retains an annual fine particle standard of 15 micrograms per cubic meter, and ratchets down the daily standard from 65 to 35 micrograms per cubic meter. It retains the 150 micrograms level for daily exposure to larger particles. The agriculture and mining industries are not exempt.
The new standard is expected to increase the number of nonattainment areas around the country significantly. Our challenge focused primarily on the fine particle portion of the rule.
Also included in the Fine Particulate Matter Petitioners Group are the American Coke & Coal Chemicals Institute, the American Forest & Paper Association, the American Iron & Steel Institute, the Chamber of Commerce, the Corn Refiners Association, the National Cotton Council of America, the National Oilseed Processors Association and the Portland Cement Association. Our petition was consolidated with others from the American Lung Association and other environmental groups, the National Mining Association, the National Cattlemen's Beef Association, 13 states, the Agricultural Retailers Association, the Utility Air Regulatory Group and others.
On Jan. 29, 2008, we filed a brief supporting EPA's decision to keep the fine particulate matter standard at 15 micrograms per cubic meter. It properly kept the limit at 15 because the risk attributed to that level of ambient exposure has stayed the same or decreased since EPA established that standard in 1997. EPA also properly set the secondary fine particulate matter standard at a level identical to the primary standards, providing increased visibility protection and providing the requisite level of public welfare protection.
We opposed a challenge to the standard that argued the EPA should have adopted recommendations of the Clean Air Scientific Advisory Committee (CASAC), because the Clean Air Act only allows that group to recommend revisions and the ultimate decision is in the discretion of the EPA Administrator.
On Feb. 24, 2009, the D.C. Circuit remanded the fine particulate standard to the EPA, as well as the EPA's decision to equate the primary and secondary fine particle standards, but upheld the coarse particulate standard. The court ruled that "the EPA did not adequately explain why an annual level of 15 μg/m3 is sufficient to protect the public health while providing an adequate margin of safety from short-term exposures and from morbidity affecting vulnerable subpopulations." It noted in particular three short-term studies that the EPA did not adequately explain away. During the remand, EPA's rule will remain in effect. It also found that EPA acted unlawfully when it failed to determine what level of visibility protection was needed to protect the public welfare. EPA's failure to set a target level of visibility was fatal to the standard it set.
With respect to an industry challenge to the regulation of coarse particulate matter, the court said that EPA need not wait for conclusive evidence of adverse health effects before regulating. It rejected the challenge and upheld this portion of EPA's regulation.