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Treatability Study Report and Feasibility Evaluation for In Situ Petroleum Hydrocarbon Remediation Field Maintenance Shop #24, 8020 South Airport Way 5.3.10 Vapor and Water Mass Removal Rates Vapor mass removal during HVDPE testing was calculated based on the initial (maximum) and final (minimum) TPH-g concentrations along with the average extraction flow rates. Based on the initial and final vapor samples collected during HVDPE testing at well FMS-MW5mass removal rate of petroleum hydrocarbon vapors decreased from 89.7 lbs/day to 36.5 lbs/day (average of 63.07 lbs/day) at the end of the test. Based on groundwater samples collected at the beginning and end of FMS-MW5 testing, the average removal rate of dissolved TPH-g was 0.021 lbs/day. Based on the initial and final vapor samples collected during HVDPE testing at well FMS-DPE1, the mass removal rate decreased from 89.29 lbs/dayto 20.9 lbs/day (average of 55.09 lbs/day) at the end of the test. The average removal rate of dissolved phase TPH-g in the liquid stream was 0.055 lbs/day during FMS-DPE1 testing. Based on the average removal rates in the liquid and vapor streams, approximately 21 pounds of petroleum hydrocarbons were removed during FMS-MW5 testing, and approximately 18.4 pounds were removed during FMS-DPE1 testing. Mass removal calculations are included in Appendix G. 5.4. AQUIFER TEST DATA REDUCTION During HVDPE procedures described above, groundwater was extracted from wells FMS-MW5 and FMS-DPE1 between May 17 and May 18, 2012. OTIE utilized drawdown data related to the HVDPE component of the treatability study to estimate transmissivity, hydraulic conductivity, and specific capacity for the aquifer. The evaluation is described below. We note that during the pumping test, the groundwater levels declined to the pump inlet (below transducers installed in both wells FMS-MW5 and FMS-DPE1). For well FMS-MW5, it was assumed that groundwater levels did not decline significantly below the transducer. For well FMS-DPE1, we were able to predict where groundwater level leveled off based on the drawdown curve. Based on the shape of the curve, groundwater leveled off at approximately 26.4 feet bgs, which was used in calculating residual drawdown. 5.4.1. Data Reduction Procedures The model used for the analysis of aquifer parameters was the Cooper -Jacob Straight Line Method. The hydrogeology in the immediate area of wells FMS-MW5 and FMS-DPE1 are screened through is unconfined to semi -confined. Because the drawdown observed in the wells is small in comparison to the saturated thickness, the Cooper -Jacob Straight Line Method is applicable to unconfined to semi -confined water -bearing units (Jacob, 1950). Groundwater levels were monitored using an In Situ Trole 9500 installed in wells FMS-DPE1, FMS-DPE2, FMS-MW5, and FMS-MW1 during the pumping tests. Wells FMS-MW5 and FMS-DPE1 were pumped at flow rates of 0.75 gallons per minutes (gpm) and 2.0 gpm, respectively, on May 17 and May 18, 2012, respectively. Groundwater extraction from wells FMS-MW5 and FMS-DPE1 was performed using pneumatic submersible pumps under high vacuum conditions. During the pumping tests, there was no drawdown observed in the observation wells. Therefore, hydrogeologic analyses were performed on the recovery data from wells FMS-MW5 and FMS-DPE1. 34 OTIE