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CAM RIA 40 identified wells are summarized on Table 2. Due to the confidential nature of DWR well information, well driller's report forms are not included in this report. 1998 Cone Penetrometer Testing (CPT) Boring Installation: In August 1998, Cambria advanced 10 CPT borings to determine the extent of hydrocarbons and MTBE detected in soil and groundwater beneath the site. No TPHg or benzene was detected in any of the soil samples collected during the investigation. MTBE was detected in soil samples collected between 20 and 34.5 fbg from boring CPT-1 only, located immediately south of the southeastern dispenser, at concentrations up to 27.0 ppm. No MTBE was detected in the soil samples collected deeper than 34.5 fbg in boring CPT-1. Soil sampling locations are shown on Figure 2, and soil analytical results are summarized in Table 1. Grab groundwater samples were collected from two discrete intervals in each of the CPT borings. No TPHg was detected in any of the grab groundwater samples collected. Benzene was detected in one grab groundwater sample only at 32 fbg in boring CPT-1 at a concentration of 13.8 parts per billion(ppb). The grab groundwater sample collected from 45 fbg in boring CPT-1 did not contain benzene. MTBE was detected in grab groundwater samples collected from borings CPT-1, CPT-2, CPT-4, and CPT-5 at concentrations up to 170, 000 ppb (32 fbg in boring CPT-1). Grab groundwater analytical results are summarized in Table 3. Investigation activities were described in Cambria's August 17, 1998 CPT Investigation Report. 1998 Interim Groundwater Remediation: Blaine Tech Services, Inc. of San Jose, California (Blaine) began weekly purging of onsite monitoring well MW-1 in November 1998 (and later of onsite extraction well EW-1). Weekly purging continued until a GWE system was installed at the site during March 2000 (see below). Purging activities were summarized in quarterly groundwater monitoring reports submitted for the site. 1999 Investigation: In February 1999, Cambria installed two groundwater monitoring wells (MW-2 and MW-3), two groundwater extraction (GWE) wells (EW-1 and EW-2), and advanced five CPT borings (CPT-11 through CPT-15) at the site. No TPHg or BTEX were detected in soil samples collected from the monitoring and GWE extraction well borings. MTBE was detected in only one saturated soil sample collected from 29.5 fbg in well EW-1, located immediately east of the southern dispenser island. Soil samples were not collected from the CPT borings. Soil eamnlino recnitc are pirnrnari7eil in Table l 0324 3