E. Bay Area Air Quality Management District
E1 The DEIR examined NO
x emissions under two different regulatory scenarios (i.e., with modifications to BAAQMD Regulation 9, Rule 11 and without such modifications) to ensure CEQA analysis of all possible project implementation scenarios. It is acknowledged in the DEIR (e.g., on page 4.5-53) that the BAAQMD intends to modify Regulation 9, Rule 11 to ensure its continued applicability to all of the electric utility steam boilers at the four Bay Area power plants, regardless of whether they are utility-owned. The NOx emissions scenario that does not include such modification can therefore be considered a worst-case scenario.E2 The DEIR does note on page 4.5-55 that the analytical maximum scenario is "extremely unlikely" to be a true operating scenario. It was used to provide a conservative analysis or, as noted in the comment, a reasonable worst-case upper bound case.
E3 The table referred to by the commenter (Table 4.5-32 on page 4.5-68 of the DEIR) projects an exceedance of the state 1-hour nitrogen dioxide standard in 1999, not of the federal 1-hour NOx standard. A more refined analysis has been carried out since the release of the DEIR. The new analysis indicates that the 1-hour nitrogen dioxide standard will not be exceeded. See response to comment B11 for details on the analysis.
E4 Based on the modeling results, the maximum offsite impacts for all three plants are relatively near the facilities, ranging from 0.5 to 1.5 miles away. At other locations that are beyond this zone, the estimated concentrations are much lower, principally because of dilution of pollutants in the atmosphere. Sensitive receptors, such as schools in ther regions around the plants, were included in the modeling analysis, and the impacts at these sensitive receptors were found to be less than significant.
E5 The commenter is correct in noting that different approaches are used in developing emissions forecasts for a basin-wide plan compared to a project-specific CEQA analysis because they serve different purposes. While a reasonable worst-case approach is appropriate for the latter, it may lead to illogical policies if used for the former. It is acknowledged that one of the reasons that the power plant emissions forecasts included in the '97 Clean Air Plan differ from those presented in the DEIR is that much of the information concerning the effects of electric utility restructuring and power plant divestiture had not been developed yet to allow for incorporation of that information by the BAAQMD into the '97 Clean Air Plan. The fact that BAAQMD will review regional emissions forecasts, including power plant emissions, and amend the regional air quality strategy, if necessary, lends support to the conclusion that the project's potential inconsistency with the regional air quality plan would be a temporary effect.
E6 The commenter is correct that even nominal increases in capacity would require new source review by the BAAQMD. As noted in the second to the last sentence of the second bulleted item on page 3-4 of the DEIR, any expansion or repowering of generating units (even under 49 MW) "would require issuance of new permits and accompanying environmental review."
E7 Please refer to responses to Comments C4 and C5.
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