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The revised modeling undertaken for the RDSEIR and RFSEIR (together, the RSEIR) resulted in changes to the conclusions in the DSEIR related to air quality impacts only. The RSEIR found certain air quality impacts (i.e. construction-related criteria pollutant emissions) could be potentially significant, but they could be mitigated to less than significant levels with an identified, new mitigation measure (i.e. new Mitigation Measure M-AQ-11). The RSEIR also found the three air quality impacts (i.e. Impacts 4.B-2, 4.B-3 and 4.B-6) the DSEIR previously identified as significant and unavoidable are actually all less than significant. The new less than significant findings for these three air quality impacts are a result of the revised modeling, as discussed above. Specifically, regarding Impact 4.B-2 (the project's operational emissions of criteria pollutant emissions), the DSEIR found that maximum net new emissions of nitrous oxide (NOx) at full buildout in 2025 would be 102 lbs./day (129 lbs./day for the project and 27 lbs./day for existing conditions), while the RFSEIR found that maximum emissions of NOx at full buildout in 2031 would be 34.2 lbs./day with mitigation (70.1 lbs./day for the project and 35.9 lbs./day for existing conditions). These values compare to the threshold of significance of 54 lbs./day; the DSEIR emissions exceed the threshold while the RFSEIR emissions do not. The RFSEIR's lower emissions are due to a number of factors, primarily: a new full buildout year of 2031, resulting in much lower mobile source (traffic) and energy (natural gas) emission factors than the full buildout year of 2025 as analyzed in the DSEIR; an updated mix of land uses to more accurately reflect the project as compared to existing conditions; reduced annual gas station throughput of 24 million gallons; and new emission factors for on-road vehicles, area sources, and energy use, as embodied in the latest version of the emissions modeling software used for the analysis, CaIEEMod version 2016.3.2 (the DSEIR used version 2013.3.2). Regarding Impact 4.B-3 and Impact 4.B-6, the DSEIR found significant and unavoidable impacts because Impact 4.B-2 was significant and unavoidable (operational criteria pollutant emissions of NOx exceeded the thresholds of significance). Because the RFSEIR found that Impact 4.B-2 is less than significant with mitigation as discussed above (both mitigated Phase 1 construction and unmitigated full-buildout operational criteria pollutant emissions of NOx do not exceed the thresholds of significance), both Impact 4.B-3 and Impact 4.B-6 are also less than significant with mitigation. 1 Mitigation Measure M-AQ-1: Construction Emissions Minimization. The project sponsor or the project sponsor's contractor shall comply with the following: 1. All off-road equipment (including water construction equipment used onboard barges) greater than 50 horsepower shall have engines that meet Tier 3 off-road emission standards. 2. Diesel engines, whether for off-road or on-road equipment, shall not be left idling for more than two minutes, at any location, except as provided in exceptions to the applicable state regulations regarding idling for off-road and on-road equipment (e.g., traffic conditions, safe operating conditions). The contractor shall post legible and visible signs in English, Spanish, and Chinese, in designated queuing areas and at the construction site to remind operators of the two-minute idling limit. 3. The contractor shall instruct construction workers and equipment operators on the maintenance and tuning of construction equipment and require that such workers and operators properly maintain and tune equipment in accordance with manufacturer specifications. Page 15 of 23