Opinion ID: 386070
Heading Depth: 1
Heading Rank: 2

Heading: pickaway county (harrison township)

Text: 10 Petitioner's comments on EPA's initial Pickaway County nonattainment designation embraced extensive air quality monitoring results. These data purportedly showed that the air surrounding C&SOE's Pickaway County plant met national air-quality standards. EPA disregarded these data, saying that petitioner's monitors were not at those points where violations of pollution standards were likely to occur. C&SOE contends that it was arbitrary and capricious for EPA to dismiss these data and to rely instead on computer modeling which reflected improbable or impossible hypothetical future circumstances rather than actual ... air quality. 11 We have already held that since the Clean Air Act itself authorizes use of computer modeling in making attainment status designations, use of such models is not per se arbitrary and capricious. Republic Steel, supra, at 804-806. More recently, in PPG Industries v. Costle, 630 F.2d 462 (6th Cir. 1980), we held that it was lawful under the Clean Air Act for EPA to base nonattainment designations on predictions of future violations of air-quality standards. See id. at 464-465. Therefore, polluters in a currently clean region can substantively attack a nonattainment designation of their region only by showing that EPA's predictions of future pollution levels are unsupported by the record. Monitored data tending to show mere past attainment of air-quality standards within an air-quality control region do not per se show the unreliability of EPA's predictions, although such data might show that EPA's modeling techniques were flawed. EPA contends that C&SOE's data cannot be used for this purpose, since the utility's monitors were not placed where EPA's model predicted the highest SO 2 concentrations would occur. C&SOE claims that this is an irrebuttable assertion, since EPA never disclosed the sites of the receptors hypothesized in its computer model. If the utility's claim were true, the agency's disregard of C&SOE's monitored data would be peremptory and arbitrary. But the claim is not true. The locations of EPA's hypothetical receptors were made a matter of public record in the technical support documents which accompanied EPA's promulgation in 1976 of emissions limits for Ohio pollution sources. 2 Petitioner's monitors were in fact not placed at the hotspots predicted by EPA's model. 3 ] We therefore cannot say that the agency's refusal to label Pickaway County attainment for SO 2 after its review of petitioner's monitored data was arbitrary and capricious. Petitioner's data did not unequivocally call EPA's computer modeling of Pickaway County into question. 12 NOTE: OPINION CONTAINS TABLE OR OTHER DATA THAT IS NOT VIEWABLE