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would not contribute substantially to an existing violation of air quality standards for regional pollutants <br />(e.g., ozone). This impact is considered less than significant. <br />Localized Emissions <br />In addition to maximum daily regional emissions, maximum localized (on -site) emissions were quantified <br />for each construction activity. The localized construction air quality analysis was conducted using the <br />methodology promulgated by the SCAQMD. Look -up tables provided by the SCAQMD were used to <br />determine localized construction emissions thresholds for the Project.36 LSTs represent the maximum <br />emissions from a project that are not expected to cause or contribute to an exceedance of the most <br />stringent applicable federal or state ambient air quality standard and are based on the most recent <br />background ambient air quality monitoring data (2019-2021) for the Project area. <br />Table 7 <br />Daily Construction Emissions <br />Daily Emissions (Pounds Per Day) <br />Construction Phase Year VOC NOx CO sox PM10 PM2.5 <br />2024 3.8 38.6 34.9 0.1 10.0 5.6 <br />2025 3.3 <br />29.8 <br />44.1 <br />0.1 <br />8.3 2.6 <br />2026 2.9 <br />15.5 <br />42.3 <br />0.1 <br />8.2 2.2 <br />2027 63.2 <br />15.7 <br />46.7 <br />0.1 <br />9.6 2.5 <br />Maximum Regional Total 63.2 <br />38.6 <br />46.7 <br />0.1 <br />10.0 5.6 <br />Regional Threshold 75 <br />100 <br />550 <br />150 <br />150 55 <br />Exceed Threshold? No <br />No <br />No <br />No <br />No No <br />Maximum Localized Total 57.5 33.0 21.7 0.1 4.1 1.8 <br />Localized Threshold N/A <br />183 <br />1,253 <br />N/A <br />13 7 <br />Exceed Threshold? N/A <br />No <br />No <br />N/A <br />No No <br />The construction dates are used for the modeling of air quality emissions in the CaIEEMod software. If construction <br />activities commence later than what is assumed in the environmental analysis, the actual emissions would be lower <br />than analyzed because of the increasing penetration of newer equipment with lower certified emission levels. <br />Assumes implementation of SCAQMD Rule 403 (Fugitive Dust Emissions) <br />Source: DKA Planning, 2023 based on CaIEEMod 2022.1.1.14 model runs. LST analyses based on five -acre site <br />with 25-meter distances to receptors in Central Orange County source receptor area. Estimates reflect the peak <br />summer or winter season, whichever is higher. Totals may not add up due to rounding. Modeling sheets included <br />in the Technical Appendix. <br />Maximum on -site daily construction emissions for NOx, CO, PM1o, and PM2.5 were calculated using <br />CaIEEMod and compared to the applicable SCAQMD LSTs for the Central Orange County SRA based <br />on construction site acreage that is five acres in area, the highest site area identified by SCAQMD for <br />their LSTs. Potential impacts were evaluated at the closest off -site sensitive receptor, which is Cabrillo <br />36 South Coast Air Quality Management District, LST Methodology Appendix C-Mass Rate LST Look -up Table, <br />revised October 2009. <br />Cabrillo Town Center <br />Air Quality ac77ca <br />PAGE 28 <br />18-674 <br />City of Santa Ana <br />10/3/2023 July 2023 <br />