Opinion ID: 221481
Heading Depth: 3
Heading Rank: 3

Heading: Air-Quality Analysis

Text: NEPA required the EIS to analyze the Project's cumulative environmental impact on the San Juan Basin and surrounding area. See Richmond, 483 F.3d at 1133; 40 C.F.R. § 1508.25. Cumulative impact is the impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency ... or person undertakes such other actions. 40 C.F.R. § 1508.7. It can result from individually minor but collectively significant actions taking place over a period of time. Id. In evaluating a proposal's cumulative impact, an agency must consider the project's proximity to historical or cultural resources, park lands, ... or ecologically critical areas. Id. § 1508.27(b)(3). As summarized by a fellow circuit: [A] meaningful cumulative impact analysis must identify five things: (1) the area in which the effects of the proposed project will be felt; (2) the impacts that are expected in that area from the proposed project; (3) other actions  past, present, and proposed, and reasonably foreseeable  that have had or are expected to have impacts in the same area; (4) the impacts or expected impacts from these other actions; and (5) the overall impact that can be expected if the individual impacts are allowed to accumulate. TOMAC, Taxpayers of Michigan Against Casinos v. Norton, 433 F.3d 852, 864 (D.C.Cir.2006) (internal quotation marks omitted). Because CBM drilling and various activities associated with the construction of CBM wells and their ancillary facilities can affect the surrounding region's air quality, the Federal Defendants used air-pollutant-dispersion modeling to assess the Project's cumulative impact on air quality and visibility. Their modeling sought to quantify potential [carbon monoxide] and [nitrogen dioxide] impacts during [well] operation, based on the period of maximum potential emissions and other emission sources located within the Analysis Area. Lessee' Supp.App., Vol. I at 315. The analysis covered 12,600 square miles of southwestern Colorado and northwestern New Mexico, and assessed the Project's air-quality impacts at Mesa Verde National Park and Weminuche Wilderness Area in Colorado. SJCA contends that the Federal Defendants' analysis nevertheless violated NEPA because they failed to assess the Project's effects on air quality and visibility in certain Class I areas within New Mexico. The Clean Air Act defines Class I areas to include national wilderness areas exceeding 5,000 acres and national parks exceeding 6,000 acres. See 42 U.S.C. § 7472(a). The Act declares as a national goal the prevention of any future... [manmade] impairment of visibility in Class I areas. Id. § 7491(a). SJCA argues that the absence of an assessment of the New Mexico areas violated NEPA's requirement to take a hard look at the impacts of the Project to these areas, which Congress has identified as being ecologically critical, and that [t]he stunted scope of [the cumulative-impact] analysis cannot be excused as a necessary line-drawing decision by the government. Aplt. Br. at 50. We disagree. Setting the boundaries of the region to be analyzed involved technical and scientific judgments within the Federal Defendants' area of expertise, and their conclusion regarding which Class I sites to include in the analysis is one to which we defer. See Kleppe v. Sierra Club, 427 U.S. 390, 414, 96 S.Ct. 2718, 49 L.Ed.2d 576 (1976) (the determination of the extent and effect of [cumulative environmental impacts], and particularly identification of the geographic area within which they may occur, is a task assigned to the special competency of the appropriate agencies); Morris, 598 F.3d at 691 ([O]ur deference to [an] agency is especially strong where [its] challenged decisions involve technical or scientific matters within the agency's area of expertise. (internal quotation marks omitted)). Both the Mesa Verde and Weminuche Class I areas are closer to the Project Area than the New Mexico Class I areas. SJCA has not demonstrated that it was unreasonable for the Federal Defendants to conclude that any visibility impacts in Class I areas would be greatest in those two areas, and impacts at other, more distant areas would be less significant. Fed. Defs. Br. at 57. We recognize that the New Mexico Environment Department disagreed with this conclusion. According to the state agency, dispersion modeling analyses demonstrated that emissions from the Four Corners region degrade New Mexico's Class I areas visibility equally or more than Colorado's Class I areas, a fact which necessitated analysis at northern New Mexico Class I areas. Aplts. Appx., Vol. II at 434-35. But the Four Corners region encompasses a far larger area (and much of it significantly closer to New Mexico Class I areas) than the Project Area. And in any event, [w]hen specialists express conflicting views, an agency must have discretion to rely on the reasonable opinions of its own qualified experts even if, as an original matter, a court might find contrary views more persuasive. Marsh, 490 U.S. at 378, 109 S.Ct. 1851; see Greater Yellowstone Coal. v. Flowers, 359 F.3d 1257, 1272 n. 14 (10th Cir.2004) ([An agency] is entitled to rely on its own experts even when their opinions conflict with those of other federal agencies, as long as its decisions are not arbitrary and capricious.). The Federal Defendants' decision to limit the study to Colorado Class I areas was not arbitrary or capricious.