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6 November 1995 AGE-NC Project No. 95-0148 Page 2 of 4 from the SI and dispose of the material at a Class I landfill. Approximately 2,000 cubic yards of materials was removed and disposed. A low permeability cap was placed over the SI in preparation for closure certification. However, closure certification has not been received. Subsurface investigation of the SI area indicated that soils immediately beneath the SI are impacted with elevated concentrations of lead (Pb) and continued investigation is required. 2.4. MONITORING WELL INSTALLATION AND SAMPLING Three two-inch diameter monitoring wells were installed at the site in September 1990. The wells were installed to depths of 70 to 72.5 feet below surface grade (bsg). At the time of installation, ground water was encountered at a depth of 58 feet bsg. Ground water samples were collected and analyzed for major ions, pH, EC, TDS, total extractable petroleum hydrocarbons, priority pollutant metals, halogenated volatile organics (EPA 601), aromatic volatile organics (EPA 602) and phenols (EPA 604). Analytical results of soil, ground water samples and ground water gradient information were included in a "Hydrologic Assessment Report" dated 14 December 1990 prepared by Kleinfelder, Inc. 2.5. QUARTERLY GROUND WATER MONITORING Quarterly ground water monitoring was initiated at the site by AGE in 1995. Samples were collected on 13 July 1995 and 4 October 1995. Details of each quarterly monitoring procedures are presented to the CVRWQCB in Quartely Reports. 3.0. PROPOSED SCOPE OF WORK In accordance with Cleanup and Abatement(C &A) Order No. 89-708, AGE will install four suction lysimeters at the site. During installation procedures, soil samples will be collected from the clay cap layer overlying the SI. The samples will be submitted to a laboratory for permeability testing. AGE proposes to install four lysimeters at the site. Two will be installed within the former SI to monitor if liquids and water are penetrating through the clay cap. While two additional lysimeters will be installed on the north edge of the clay cap, in order to determine the lateral migration of liquids beneath the cap into the former SI. The proposed lysimter locations are depicted in Figure 2.