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C A M B R I A Wellhead Survey: A California licensed land surveyor will survey the top of casing elevations of wells MW-5, MW-6, and MW-8 relative to mean sea level.. These results will be tied in to the existing survey data for the adjacent former Chevron site investigation. Site Investigation: Two CPT soil borings (CPT-1 and CPT-2) are proposed to identify the second water-bearing zone and obtain a groundwater sample from it. The proposed boring locations areshown on Figure 2. A Cambria geologist will supervise the drilling. Soil will'be logged continuously in boring CPT-I using electronic CPT technology. The boring will be advanced through the second water-bearing zone beneath the site, expected to be at approximately 80 to 85 fbg. No soil or groundwater samples will be collected from this boring. Boring CPT-2 will be drilled initially with hollow-stem augers into the less permeable soil layer between the first two water-bearing zones as identified in boring CPT-l. A soil sample will be collected at this depth to confirm that the soil at the bottom of the boring has not been impacted. Then a conductor casing will be placed in the boring, and the boring's annular space will be sealed with neat cement grout from the bottom up. After the seal has set, CPT water sampling equipment will be advanced through the conductor casing and into the second water-bearing zone to collect a groundwater sample. Five shallow hollow-stem auger soil borings (SB-5 through S13-9) are also proposed to further delineate the lateral extent of impacted soil identified near the northernmost dispenser island. The proposed boring locations are presented on Figure 2. The borings will be drilled to 40 fbg, unless field observations indicate that soil at that depth is impacted by petroleum constituents. A Cambria geologist will supervise the drilling and describe encountered soils in the borings using the Unified Soil Classification System and Munsell Soil Color Charts. Soil samples will be collected at five-foot intervals for describing soil, possible chemical analysis, and organic vapor screening with a photo-ionization detector (PID). PID readings will be recorded on the boring log for each boring. Soil samples from borings SB-5 through SB-9 and CPT-2 will be retained in stainless steel or j brass sample tubes and will be covered on both ends with Teflon sheets and plastic end caps. The groundwater sample from CPT-2 will be retained in glass vials preserved with hydrochloric acid. Soil and groundwater samples will be labeled, entered onto a chain-of- custody record, and placed into a cooler with ice for transport to a State of California certified laboratory for analyses. The scope of work described in this work plan will be performed under the supervision of a registered geologist. 1346 4