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Draft Removal Action Completion Report <br /> Neighborhood C, <br /> Mountain House,CA <br /> Page 18 <br /> 9.2 SUMMARY AND RECOMMENDATIONS <br /> MHD conducted a Removal Action for the Neighborhood C project located in San Joaquin County in <br /> Mountain House, California in general accordance with the DTSC-approved RAW and subsequent <br /> interim progress reports by Condor.Approximately 70,000 in-place yds3 of waste soil were excavated and <br /> entombed below the future location of the southbound lanes of Great Valley Parkway between Grant Line <br /> Road and Mascot Boulevard. <br /> Dieldrin removal and air monitoring operations began on October 18, 2013. Once the initial 0.5 feet of <br /> surface soil had been removed, one confirmation sample per one-acre subparcel was collected and <br /> analyzed for dieldrin. Most of the subparcels did not meet the cleanup goal and additional excavation was <br /> required. Additional iterations of excavation and confirmation sampling proceeded until the cleanup goal <br /> was achieved on all subparcels. During movement of dieldrin-containing soil, air monitoring was <br /> conducted by monitoring real-time dust concentrations and air sampling for dieldrin at the fencelines.No <br /> dieldrin was detected in air samples during the soil removal, and the dust control plan was successfully <br /> implemented. All confirmation sampling laboratory analytical results indicate that the cleanup goal has <br /> been met for remaining soil beneath residential portions of Neighborhood C. <br /> Waste characterization results for the entombment area beneath Great Valley Parkway indicate dieldrin <br /> concentrations are above the action level of 0.035 mg/kg for administrative controls specified in the <br /> RAW. Waste soil encapsulation beneath Great Valley Parkway is protective of human health and the <br /> environment based on engineering and future administrative controls. Engineering controls include a cap <br /> of non-contaminated fill soil and pavement of the roadway. Conservatively, SHM implemented an <br /> additional engineering control that was not originally included in the RAW: an orange warning fabric was <br /> installed on top of the waste soil. Administrative controls will consist of a Land Use Covenant that will <br /> ensure the waste soil encapsulation area will not be used for sensitive land use in the future. <br /> Based on laboratory analytical results for the confirmation and waste characterization samples, <br /> Condor recommends that the residential portion of the Site be approved for occupancy, and that a <br /> Land Use Covenant be executed for the waste soil encapsulation area. <br />