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updated assessment of health risks to nearby sensitive receptors from Project construction and operation should be included in a revised CEQA evaluation for the Project. Screening -Level Assessment Indicates Significant Impact In an effort to demonstrate the potential risk posed by Project construction and operation to nearby sensitive receptors, we prepared a simple screening -level HRA. The results of our assessment, as described below, provide substantial evidence that the Project's construction and operational DPM emissions may result in a potentially significant health risk impact not previously identified by the Addendum. In order to conduct our screening level risk assessment, we relied upon AERSCREEN, which is a screening level air quality dispersion model. 11The model replaced SCREEN3, and AERSCREEN is included in the OEHHAl2 and the California Air Pollution Control Officers Associated (CAPCOA)" guidance as the appropriate air dispersion model for Level 2 health risk screening assessments ("HRSAs"). A Level 2 HRSA utilizes a limited amount of site -specific information to generate maximum reasonable downwind concentrations of air contaminants to which nearby sensitive receptors may be exposed. If an unacceptable air quality hazard is determined to be possible using AERSCREEN, a more refined modeling approach is required prior to approval of the Project. We prepared a preliminary HRA of the Project's construction and operational health -related impact to residential sensitive receptors using the annual PMlo exhaust estimates from the SWAPE annual CaIEEMod output files. According to the Addendum, the nearest sensitive receptor is located approximately 370 feet, or roughly 113 meters, east of the Project site (Appendix C, pp. 83). Consistent with recommendations set forth by OEHHA, we assumed residential exposure begins during the third trimester stage of life. The Project's construction CaIEEMod output files indicate that construction activities will generate approximately 190 pounds of diesel particulate matter (DPM). The AERSCREEN model relies on a continuous average emission rate to simulate maximum downward concentrations from point, area, and volume emission sources. To account for the variability in equipment usage and truck trips over Project construction, we calculated an average DPM emission rate by the following equation: grams 190 Ibs 453.6 grams 1 day 1 hour Emission Rate (second) = x x x = 0.001368 g/s second 729 days lbs 24 hours 3,600 seconds Using this equation, we estimated a construction emission rate of 0.001368 grams per second (g/s). Subtracting the 729-day construction duration from the total residential duration of 30 years, we assumed that after Project construction the MEIR would be exposed to the Project's operational DPM 11 "AERSCREEN Released as the EPA Recommended Screening Model," USEPA, April 11, 2011, available at htta://www.eaa.eov/ttn/scram/Ruidance/clarification/20110411 AERSCREEN Release Memo.odf 12 "Risk Assessment Guidelines Guidance Manual for Preparation of Health Risk Assessments." OEHHA, February 2015, available at: https://oehha.ca.gov/media/downloads/crnr/2015guidancemanual.pdf " "Health Risk Assessments for Proposed Land Use Projects," CAPCOA, July 2009, available at: http://www.capcoa.org/wp-content/uploads/2012/03/CAPCOA HRA LU Guidelines 8-6-09.pdf 7