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' Underground Storage Tank Remo and Assessment Sears Unit, #0555, Tracy, California ' 3.4 Soil Assessment Soil assessment samples were collected immediately under the removed UST at both ends and in the ' center of the removed UST. The three soil samples were collected at an approximate depth of 9.5 feet bgs. In addition, one sample was collected from beneath the pipe joint at a approximate depth of 9.5 feet bgs and two samples were collected from the excavated soil (one separate sample each from the tank excavation and piping excavation stockpiled soils). No visual impacts or odors were detected in the soils. ' The six soil samples were packed in a pre-chilled cooler and delivered to Sequoia Analytical for analysis as detailed in Section 3.1. ' SVOCs and VOCs were not detected in any analyzed soils samples. With the exception of concentrations of diesel and motor oil range organics and TRPH detected in the piping stockpile sample#0452SS003 (10,28,and 68 milligrams per kilogram [mg/kg],respectively),TPH and TRPH were not detected in analyzed samples. These detected concentrations are below the Regional Water Quality Control Board ' Screening Level for Threat to Groundwater for TPH and TRPH of 100 mg/kg. Metals were detected in all six soil samples at concentrations below each corresponding California Total Threshold Limit ' Concentration(TTLC)reference value. Analytical results for the assessment samples are presented in Tables 1 and 2 and sample locations are included on Figure 3. The complete laboratory report is included in Appendix B. ' 3.5 Aboveground Storage Tank (AST) Installation Prior to removal of the UST system,Three Kings installed a replacement AST within the warehouse ' building on December 20,2004. A 500-gallon Convault Secondary Containment Fireguard AST was installed in the northwest comer of the building. The AST includes an emergency vent on the secondary ' containment, a leak alarm counsel, and a double diaphragm pump to transfer waste oil to the AST. MACTEC provided the AST specifications to the City of Tracy Fired Department prior to installation for ' confirmation that the AST met applicable specifications. MACTEC received confirmation that the AST met the City of Tracy Fire Department standards and specifications on November 24, 2004. 1 5 MACTEC Engineering and Consulting, Inc.