F. PSEG Resources, Inc.

F1 The Initial Study’s allocation of 2,100 tons of NOx per year between Encina and South Bay Power Plants was based on a five-step process. First, a percentage split between the two plants was derived from "total installed capacity," which is essentially the same as "design capacity." Second, a percentage split was derived assuming a 100% capacity factor with NOx reduction equipment in operation. In this case, the applicable NOx reduction equipment included the equipment installed in 1997 as well as additional equipment that had been tentatively scheduled for installation by SDG&E in 2000. Third, the percentage splits developed using the two methods was averaged. Fourth, since the second method produced different percentage splits for 1999 and 2000, the percentage splits for 1999 and 2000 were also averaged. Finally, the resulting percentage splits were applied to the emissions cap of 2,100 tons per year and the resulting annual emissions were rounded to the nearest hundred tons.

From a regional air quality perspective, which is appropriate given the nature of ozone, the impact would be reduced to less than significant regardless of the particular allocation of NOx emissions between the two plants so long as the combined total for the two plants would not exceed 2,100 tons per year in 1999 and 2000.

F2 Each of the plants’ design capacity was one of the factors used to develop the NOx allocations set forth in the Initial Study. While the commenter would have preferred the use of the plants’ design capacities as the sole factor in determining the allocations, from the environmental perspective, the plant-specific allocation is not relevant. So long as the two plants together emit no more than 2,100 tons per year of NOx during 1999 and 2000, the associated impact would be reduced to less than significant. The specific plant allocations were developed in consultation with SDG&E under CEQA Guidelines Sections 15070(b) and 15063(g), and they reflect an approach agreed upon by SDG&E to modify its project to avoid the significant effect identified during the process of preparing the Initial Study.

F3 Mitigation measure 4.5.a.1 would most likely be implemented by adding the applicable provisions as an additional condition of the SDAPCD permit for each of the boilers at the Encina and South Bay Power Plants. In other words, each boiler would operate subject to a plant-wide annual emissions limit during 1999 and 2000. Development of boiler-unit-specific NOx allocations would not be necessary to avoid the potential significant effect of the project, which is adequately addressed by limiting the overall NOx emissions from both the Encina and South Bay boilers to 2,100 tons per year or less in 1999 and 2000. In addition, allocation on a unit-specific basis may inhibit the flexibility of plant operations needed to meet demand while achieving environmental (e.g., annual emissions limits) and reliability (as required under the must-run contracts) standards.