Reso 2020-019 - Laserfiche WebLink

Home

SAN LEANDRO SHORELINE DEVELOPMENT EIR ADDENDUM PROJECT CITY OF SAN LEANDRO TABLE 3-2 CONSTRUCTION RISK SUMMARY Project Level Risk Cancer Risk Chronic Der million) a Hazards Modified Project - Off -Site Resident 3.2 0.010 0.01 Threshold 10 1.0 0.3 µg/m3 Exceeds Threshold No No No Cancer Risk (per million) Chronic Adult Child Hazards PM2.5d Original Project — Off-site Resident 1.4 7.9 0.050 0.24 Threshold 10 10 1.0 0.3 µg/m3 Exceeds Threshold No No No No Note: With incorporation of certified EIR Mitigation Measure AIR -5: Tier 3 engines and Level 3 diesel particulate controls/filters for equipment 50 hp or greater. a. Incremental cancer risks determined using latest Guidance Manual for Preparation of Health Risk Assessments from the Office of Environmental Health Hazard Assessment (OEHHA, 2015). Per the latest OEHHA guidance, starting with the third trimester, residential risks are calculated for each individual age group (i.e., the third trimester to 0 year age bin, the 0 to 2 years age bin, and the 2 to 9 years age bin), assign proper exposure parameters for each individual age group, sum cancer risks for individual age groups to estimate cancer risk for a 30 -year exposure duration. b. Per discussion with BAAQMD in 2016, only the exhaust PM23 concentrations are evaluated in the health risk assessment, as fugitive PM23 impacts are mitigated by Mitigation Measure AIR -2 of the Certified EIR (fugitive dust best management practices). c. OEHHA updated the incremental cancer risk calculations in 2015, after the Certified EIR analysis was conducted, in which the child and adult scenarios are combined into a single cancer risk determination. d. In the Certified EIR, the total PM2.5 concentrations were included in the health risk assessment (fugitive PM23 plus exhaust PM23). Thus, PM23 concentrations for the original project are higher than the modified project. The results of the HRA are based on the maximum receptor concentration over a 4 -year construction exposure period for off-site receptors, assuming 24-hour outdoor exposure, and averaged over a 70 -year lifetime. The health risk values were calculated and are summarized in Table 4. The results indicate that with mitigation, the incremental cancer risk for off-site residents proximate to the site during the construction period is 3.2 per million, which is below the cancer risk threshold of 10 per million. For non - carcinogenic effects, the hazard index identified for each toxicological endpoint totaled less than one for off-site residents. Therefore, chronic non -carcinogenic hazards are within acceptable limits. In addition, PM2.5 annual concentrations are below the BAAQMD significance thresholds for off-site residents. It should be noted that the Certified EIR also included an evaluation of health risks for new on-site residents which may have been present and exposed to emissions from the project's final year of the construction. The calculated health risks for on-site residents were much lower than the calculated risks for off-site residents due to a lower exposure duration (1 year as compared to 4 to 5 years of exposure) and generally being located up -wind of construction activities. Similarly, the potential health risks for the new on-site residents of the multi -family residential development at the south end of the project site are anticipated to be much lower than the risks for off-site residents due to the same circumstances. As health risks to off-site residents do not exceed BAAQMD's thresholds with implementation of Mitigation Page 32 PlaceWorks