Opinion ID: 187435
Heading Depth: 3
Heading Rank: 1

Heading: First Factor:.EPA's Characterizations of County Emissions

Text: The first of the nine factors EPA uses to designate areas calls for the agency to consider how emissions levels contribute to nearby PM2.5 violations. In describing these levels, EPA characterizes a county's emissions as low, high, significant, insignificant, and so forth. State petitioners argue that EPA characterized county emissions inconsistently, providing further evidence that the designations were arbitrary. For example, petitioners claim it is manifestly arbitrary to designate as attainment counties with emissions levels EPA characterized as low based on weighted emissions scores of 9.4 (Sevier County, Tennessee) and 6.3 (Jasper County, Georgia), while designating as nonattainment counties with lower scores of 4.5 (Orange County, New York), 3.7 (Westchester County, New York), and 1.9 (Rockland County, New York). States' Opening Br. 34. As explained above, a weighted emissions score reflects only a county's share of a C/MSA's total emissions. Weighted emissions scores cannot be used in any meaningful way to compare emissions levels between counties in different C/MSAs. Because cumulative emissions scores for all counties within a C/MSA must total 100, areas with few counties (like the Athens, Georgia, MSA) will invariably have relatively larger county-level scores than areas with numerous counties (like the NY-NJ-CT-PA C/MSA), even though emissions levels in the smaller C/MSA may be lower. Likewise, petitioners argue that two instances in which EPA revised a county designation from nonattainment to attainment show that its characterization of emissions data and subsequent designations were arbitrary. EPA originally described the emissions levels in Woodford County, Kentucky, as significant and designated it as nonattainment. Technical Support Document § 6.4.3.3 (Factor 1). But EPA later concluded  without any change in emissions levels  that the county has relatively low emissions, id. (Justifications for Changes to EPA Recommendations Contained in the June 24, 2004, Letters to States), and revised its designation to attainment. These changes, petitioners argue, reflect the flawed manner in which EPA applied the first factor. But EPA adequately explained the change. After the initial designation, Kentucky submitted evidence that PM2.5 violations in nearby Fayette County were due to local sources, not emissions from Woodford County as originally thought. Id. Petitioners reply that EPA used the new data to explain the change in Woodford County's designation, not the change in EPA's assessment of emissions levels. To the extent that is even true, though, we can reasonably discern EPA's path. Given that the weighted emissions score is a rough estimate of a county's relative (and relevant) emissions in the first place, EPA simply interpreted the numeric score differently when the new data suggested its facial significance was inaccurate. In the same vein, petitioners contend EPA acted arbitrarily in revising its designation for Jasper County, Georgia. Finding significant emissions that potentially contribute to PM2.5 violations in other parts of the region, EPA originally designated the county as nonattainment. See id. § 6.4.2.2 (Factor 1). Data later submitted by Georgia, however, showed that emissions from a source in Jasper County were actually insignificant, prompting EPA to redesignate the county as attainment. See id. § 6.4.2.1 (Justification for Changes to EPA Recommendations Contained in the June 24, 2004, Letters to States); Letter from Ron Methier, Chief, Air Prot. Branch, Ga. Dep't of Natural Res., to Beverly Bannister, Dir., Air, Pesticides & Toxics Mgmt. Div., EPA Region 4, at 2 (Nov. 1, 2004). Far from being arbitrary, these revised designations demonstrate the reasonableness of EPA's case-by-case approach to applying the first factor.