Opinion ID: 768833
Heading Depth: 4
Heading Rank: 2

Heading: Significant Contribution of Industrial Boilers

Text: 106 CIBO challenges EPA's decision to include non-EGU boilers in the rule without having isolated non-EGU emissions to determine whether they significantly contribute to the interstate ozone transport problem and whether implementing highly cost-effective emissions reduction measures on industrial boilers would ameliorate nonattainment in downwind states. CIBO maintains that non-EGU boilers typically have significantly shorter stacks than EGUs and that their emissions, as a result, fall below the mixing layer that promotes long-range NOx transport. Therefore, CIBO contends, industrial boilers as a group can have no impact on long-range ozone transport. However, this factual claim fails in view of contrary evidence in the record. OTAG's Executive Report states as one of its major conclusions that [b]oth elevated (from tall stacks) and low-level NOx reductions are effective. Executive Report at 4. EPA reiterated this finding by OTAG in the NPRM, see Proposed Rule, 62 Fed. Reg. at 60,332, it relied on the finding, and it appears that members of CIBO never challenged it during the comment period. Therefore, we cannot say EPA's inclusion of non-EGUs in the group of significantly contributing sources was arbitrary. 107