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DRAFT • Levine•Fricke•Recon 3.1.3 Monitoring Wells Sixteen sites where monitoring wells have been installed are located in the Study Area (Table 3; Figure 5). Monitoring has been conducted at these sites to investigate groundwater affected by fuel spills and leaking underground storage tanks. According to SJC PHS/EHD, two of these sites have been closed (map identification numbers 3 and 16 on Figure 5). A total of 92 active monitoring wells and 17 abandoned monitoring wells are located in the Study Area. A total of 34 monitoring wells have been installed at or adjacent to Lincoln Center, including 15 wells installed by contractors for LPL and 2 wells installed by LFR as part of the previous and ongoing investigation being conducted at Lincoln Center, 7 wells installed at the Chevron service station, and 12 wells installed at and near the Exxon service station. One monitoring well at the Chevron service station has been abandoned (Table 4; Figure 5). A discussion of well construction data, groundwater elevation, and analytical results of groundwater samples collected from monitoring j wells installed at the Chevron and Exxon service stations are provided in Sections 3.2 ! and 3.3, respectively. 3.2. Well Construction Data 3 Available well construction data have been compiled for domestic, municipal supply, and monitoring wells located in the Study Area. Selected wells located in the vicinity of the Site were then evaluated for potential use in providing information to assist in the characterization of groundwater quality and hydraulic characteristics of the A-, B-, and C-zone aquifers at the Site. This evaluation had previously been conducted for ° existing Site monitoring wells, as described in the Monitoring Well Integrity Assessment Report (LFR 1996c). Based on LFR's current knowledge of the hydrogeology of the Site, the top of the A- zone aquifer extends from approximately 40 to 55 feet below ground surface (bgs), the bottom of the A-zone aquifer extends from approximately 75 to 80 feet bgs, the B-zone aquifer extends from approximately 90 to 140 feet bgs, and the C-zone aquifer extends from approximately 180 to 250 feet bgs (LFR 1996a). 1 3.2.1 Domestic Wells Well construction data for domestic wells located in the Study Area are limited, based on the review of publicly available data (Table 1). According to the available records, domestic wells in the Study Area have been installed to depths ranging from i approximately 50 feet bgs to 270 feet bgs. Well construction data are available for two of the three domestic wells located downgradient from Lincoln Center. According to the Water Well Drillers Report for a well located at 6632 Pacific Avenue (the former Safeway store), the well was installed i 4111WELL.AMJ:AMJ Page i J