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6�L�/tVF"EL®ER Bright People.Right Solutions. emissions to emission rates for dispersion modeling. Diesel particulate matter only has long-term risk exposures; thus, only the annual emissions were calculated and used for modeling. Truck trip estimates were based on information provided by the project applicant. Emission rates were determined from the EMFAC2007 emission model for various future years, with regulatory requirements applied (e.g., 2010 RRP reductions and newer trucks by 2023). An average emission rate was then determined based on a 70- year period (i.e., the exposure time of a residential receptor). The emission rates included running emissions both on and off the project site, and idling emissions. Emissions of diesel PM from trucks were assessed using the EPA AERMOD (v. 11103) model, using the BREEZE software (v 7.3.0). 1 Sensitive receptors were chosen based on where workers or residents would be located for long term exposure scenarios using a combination of aerial photographs and site reconnaissance. The primary sensitive receptors were the residences located across Weber Avenue from the facility. Worker receptors were depicted as discrete receptors located at areas where businesses were identified or where workers activities could occur on a routine basis. This includes industrial offices, grocery stores, convenience stores, retail outlets, businesses, etc. No discrete receptors (i.e., hospitals, schools, churches, parks and daycare centers) were identified in the area of concern. Risk characterization refers to the process of quantifying the risk associated with a given exposure to a toxic air pollutant. The focus of the health risk analysis for the project was the inhalation pathway as the primary exposure route for diesel particulate matter. The CARB approved risk assessment health values that include cancer and chronic factors of 3.0E-04 and 5.0E+00, respectively. To determine the risk results, these factors were multiplied by the associated concentration value provided by the model. For residents, the exposure is assessed based on 24 hours per day, 7 days per week for 70 years. For workers, the exposure is based on 50 years, 8 hours per day, 5 days per week. Thus, the risk to the workers is 16% of the risk to the residents. For this project, the significance thresholds for health risk associated with diesel particulate emissions were 10 cases of cancer per 1,000,000 and a Health Hazard index of 1.0 for chronic conditions, per GAMAQI. Table 3-2 shows the results of the health risk analysis for the project. As shown in Table 3-2, the health risk associated with elevated diesel particulate emissions at the project site would be below the significance thresholds. Therefore, the project would have no significant impact related to diesel particulate emissions on nearby residents or on workers at the project site. Refer to Appendix A for more detailed information on health risk analysis methodology and results. 121339/ST011 R226 3-22 October 14, 2011 Copyright 2011 Kleinfelder