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4 depth of approximately 60 feet and were completed with 20 feet of 2-inch-inside-diameter 0.020- slotted polyvinyl chloride(PVC)casing and 40 feet of 2-inch-inside-diameter PVC blank canine. ed for analysis of benzene, toluene and xylene During drilling, soil samples were collect (BTX),and total petroleum hydrocarbons (TPH). Two soil samples,one from 40 feet in MW-3 and one from 40 feet in MW-4 showed detectable levels of BTX and TPH. Geologic logs of MW-2 through MW-4 indicated no gasoline odor to a depth of 40 fset. Below 40 feet to the total depth of each borehole (approximately 60 feet), gasoline odor was present. The geologic lig of MWA indicates gasoline odor notcvt to roughly 25 feet and no odor detected from 25 to 58 fret. Groundwater samples were taken from each of the four wells and analyzed for BTX and TPH. Groundwater from monitoring wells MW-3 and MW-4 had detectable levels of BTX and TPH. Groundwater from MW-I and MW-2 had very low to nondetectable levels of BTX and TPH. Analytical results are shown in Table L Brown and Caldwell (RC} was retained by GLDNI in late 1985 to conduct a second site investigation at the site. On February 11, 1986,five boreholes,GL-1 through GL-5,were drilled at the site to identify the vertical and lateral extent of hydrocarbon contamination(Figure 2). The locations of the boreholes were selected on the basis of: (1) lunation of the former underground storage tanks and pump islands, (2)information gained from data review and preliminary stages of the field work, (3) recommendation of a Count- -epresentative based on her recollect,on of where the tanks and pump islands were formerly located. Undisturbed soil samples were obtained from specific depths during the drilling of the boreholes and analyzed for TPH and BTX. Analytical results are, shown in Table 2. Hydrocarbons were present in boreholes GL2, GL3, and in low levels in borehole GLS. -- The four existing monitoring wells (Figure 2)were purged and sampled during BC's 1986 site investigation. The analytical results of the groundwater samples :tie shown in Table 1. Table 1 also shows BTX and TPH results from groundwater samples collected by J K_.. On July 9, 1986, BC installed an additional monitoring well at the site (MW-5). The monitoring well was drilled to a depth of approximately 60 feet and completed with 50 ftet aF 2-inch-inside-diameter 0.020 slotted PVC casing and 30 feet of 2-inch-inside dian ac:ter blank PVC casing. During drilling, a soil sample was collected at a depth of 44 feet for analysis of BTX and TPH. The analytical results are shown in Table 2. A groundwater sample was collected from MW-5 on duly 9, 1956 and analyzed for BTX and TPH. Analytical results are shown in Table 1. Hydrocarbons were.present in both the soil and groundwater of MW-5. Some ime in 1987 the site was renovated,and a building was constructed over monitoring well MW-2. Access to the well remains,but modifications to the building will have to be made (i.e.,a trap door over the well) before t ie sampling can be accomplished.