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3 lifetime of the Project, we can reasonably assume that the Project will operate for at least 30 years, if not more. Therefore, health risks from Project operation should have also been evaluated by the DEIR, as a 30‐year exposure duration vastly exceeds the 2‐month and 6‐month requirements set forth by OEHHA. These recommendations reflect the most recent health risk policy, and as such, an updated assessment of health risks to nearby sensitive receptors from construction and operation should be included in a revised California Environmental Quality Act (CEQA) evaluation for the Project. In an effort to demonstrate the potential risk posed by the Project to nearby sensitive receptors, we prepared a simple screening‐level HRA. The results of our assessment, as described below, demonstrate that construction and operational DPM emissions may result in a potentially significant health risk impact that was not previously identified or evaluated in either the DEIR or FEIR. In order to conduct our screening level risk assessment, we relied upon AERSCREEN, which is a screening‐level air quality dispersion model. 4 The model replaced SCREEN3, which is included in OEHHA5 and CAPCOA6 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 health risk screening assessment of the Project's construction and operational impacts to sensitive receptors using the estimates from the DEIR’s air models for construction and operation The DEIR states that the closest sensitive receptors to the Project site are single‐family residences near the Project site (p. 4.2‐11). Thus, a receptor distance of 25 meters was used in our analysis. Consistent with recommendations set forth by OEHHA, we used a residential exposure duration of 30 years, starting from the third trimester of pregnancy. We also assumed that construction and operation of the Project would occur consecutively, with no gaps between each Project phase. Our calculated annual emissions indicate that construction activities will generate approximately 378 pounds7 of DPM over a 536‐day construction period. The AERSCREEN model relies on a continuous average emissions rate to simulate maximum downwind concentrations from point, area, and volume emissions sources. To account for the variability in construction equipment usage over the many phases of Project construction, we calculated an average DPM emission rate for construction by the following equation. 4 “AERSCREEN Released as the EPA Recommended Screening Model,” USEPA, April 11, 2011, available at: http://www.epa.gov/ttn/scram/guidance/clarification/20110411_AERSCREEN_Release_Memo.pdf 5 “Risk Assessment Guidelines Guidance Manual for Preparation of Health Risk Assessments.” OEHHA, February 2015, available at: http://oehha.ca.gov/air/hot_spots/2015/2015GuidanceManual.pdf 6 “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 The DEIR fails to provide CalEEMod output files containing the annual emissions estimates for the Project’s construction air model. Therefore, we used the maximum daily DPM emissions estimates from the DEIR’s construction air model summer output file, provided in the Magnolia at the Park Air Quality Impact Analysis, to then calculate an annual DPM emissions estimate (Appendix I, pp. 577).