Opinion ID: 815697
Heading Depth: 4
Heading Rank: 1

Heading: When a proposed source’s ambient impacts

Text: warrant a comprehensive (cumulative) source impact analysis; (2) the size of the impact area within which the air quality analysis is completed, and (3) whether the emissions increase from a proposed new major stationary source or major modification is considered to cause or contribute to a violation of any NAAQS. Id. at 64,890. In adopting the SMC, the EPA emphasized that it retained discretion “to determine when it may be appropriate to exempt a proposed new major stationary source or major modification from the ambient monitoring data requirements 9 under the PSD rules.” Id. at 64,895. The rule codified the SILs at 40 C.F.R. § 51.166(k)(2) and 40 C.F.R. § 52.21(k)(2), and the SMC at 40 C.F.R. § 51.166(i)(5)(i)(c) and 40 C.F.R. § 52.21(i)(5)(i)(c). 75 Fed. Reg. at 64,902–07. The rule also codified the PM2.5 SILs in the EPA’s regulations on new source review and permitting requirements at 40 C.F.R. § 51.165(b)(2). Unlike the PSD regulations (40 C.F.R. §§ 51.166, 52.21), § 51.165(b)(2) does not use the SILs to exempt a source from conducting a cumulative air quality analysis. Instead, § 51.165(b)(2) states that a proposed source or modification will be considered to cause a violation of a NAAQS when that source or modification would, at a minimum, exceed the SIL in any area that does not or would not meet the applicable NAAQS.