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8 for an additional 28 years, approximately. The Project’s operational CalEEMod emissions indicate that operational activities will generate approximately 78 pounds of DPM per year throughout operation. Applying the same equation used to estimate the construction DPM rate, we estimated the following emission rate for Project operation: 𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸 𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 �𝑔𝑔𝑔𝑔𝑅𝑅𝐸𝐸𝐸𝐸𝐸𝐸𝑅𝑅𝑠𝑠𝐸𝐸𝐸𝐸𝑠𝑠�= 78.2 𝑙𝑙𝑙𝑙𝐸𝐸 365 𝑠𝑠𝑅𝑅𝑑𝑑𝐸𝐸 × 453.6 𝑔𝑔𝑔𝑔𝑅𝑅𝐸𝐸𝐸𝐸𝑙𝑙𝑙𝑙𝐸𝐸 × 1 𝑠𝑠𝑅𝑅𝑑𝑑24 ℎ𝐸𝐸𝑜𝑜𝑔𝑔𝐸𝐸 × 1 ℎ𝐸𝐸𝑜𝑜𝑔𝑔3,600 𝐸𝐸𝑅𝑅𝑠𝑠𝐸𝐸𝐸𝐸𝑠𝑠𝐸𝐸 =𝟎𝟎.𝟎𝟎𝟎𝟎𝟎𝟎𝟎𝟎𝟎𝟎𝟎𝟎 𝒈𝒈/𝒔𝒔 Using this equation, we estimated an operational emission rate of 0.001125 g/s. Construction and operational activity was simulated as a 1.7-acre rectangular area source in AERSCREEN with dimensions of 83 meters by 83 meters. A release height of three meters was selected to represent the height of exhaust stacks on operational equipment and other heavy-duty vehicles, and an initial vertical dimension of one and a half meters was used to simulate instantaneous plume dispersion upon release. An urban meteorological setting was selected with model-default inputs for wind speed and direction distribution. The AERSCREEN model generates maximum reasonable estimates of single-hour DPM concentrations from the Project site. EPA guidance suggests that in screening procedures, the annualized average concentration of an air pollutant be estimated by multiplying the single-hour concentration by 10%.14 AS previously stated, there are residential sensitive receptors located approximately 100 meters from the Project site. The single-hour concentration estimated by AERSCREEN for Project construction is approximately 1.954 µg/m3 DPM at approximately 100 meters downwind. Multiplying this single-hour concentration by 10%, we get an annualized average concentration of 0.1954 µg/m3 for Project construction at the nearest sensitive receptor. For Project operation, the single-hour concentration is estimated by AERSCREEN is approximately 1.606 µg/m3 at approximately 100 meters downwind. Multiplying this single-hour concentration by 10%, we get an annualized average concentration of 0.1606 µg/m3 for Project operation at the nearest sensitive receptor. We calculated the excess cancer risk to the residential receptors both maximally exposed and located closest to the Project site using applicable HRA methodologies prescribed by OEHHA and the SCAQMD. Consistent with the construction schedule proposed by the Addendum, the annualized average concentration for construction was used for the entire third trimester of pregnancy (0.25 years) and for 1.75 years of the infantile stage of life (0 – 2 years). The annualized average concentration for operation was used for the remainder of the 30-year exposure period, including the remaining infantile stage of life, child stage of life (2 – 16 years), and adult stage of life (16 – 30 years). Consistent with OEHHA, SCAQMD, BAAQMD, and SJVAPCD guidance, we used Age Sensitivity Factors (ASFs) to account for the heightened susceptibility of young children to the carcinogenic toxicity of air 14 “Screening Procedures for Estimating the Air Quality Impact of Stationary Sources Revised.” EPA, 1992, available at: http://www.epa.gov/ttn/scram/guidance/guide/EPA-454R-92-019_OCR.pdf; see also “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, p. 4-36