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3.0 WATER QUALITY SAMPLING AND ANALYSIS Groundwater samples were collected from the five monitoring wells located at the property on September 3, 1993 All groundwater samples were analyzed for total petroleum hydrocarbons (TPH)using DHS LUFT (EPA Method 8015 Modified), for benzene, toluene, ethylbenzene, and xylenes (BTEX) using EPA Method 602 and for soluble lead using EPA Method 7421 Following the purging of at least three casing-volumes of groundwater from the well using a peristaltic pump, samples were collected using a clean disposable bailer The groundwater was decanted and sealed in laboratory provided containers, labelled, placed into plastic zipper-lock bags and placed in a cooler containing ice The samples were delivered under chain-of-custody procedures to MBT Laboratories, a state certified laboratory, for analysis Analytical results of the September 1993 groundwater sampling event are shown in Figure 3, and the September 1993 results and previous sampling events results are presented in Table 2 Laboratory analytical data sheets and chain-of-custody records are included to Appendix H 4.0 CONCLUSIONS The groundwater sample collected from MW1 in September 1993 had no concentrations of TPH and BTEX at or above the laboratory limit of detection The groundwater sample collected from monitoring well MW2 had no concentrations of TPH above the laboratory limit of detection The laboratory analytical data indicated that detectable concentrations of benzene, ethylbenzene and total xylenes were present in the groundwater sample collected from MW2 at concentrations of 7 1 µg11, 1 6 µg/l and 7 5 µg11, respectively The groundwater sample collected from monitoring well MW3 had no detectable concentrations of TPH, however, the analytical data indicated that benzene and total xylenes were present at a concentrations of 11 µg11 and 1 2 µl1, respectively L Maximum concentrations of petroleum hydrocarbons in groundwater samples collected in September 1993 were detected in samples from well MW4 The groundwater sample collected from monitoring well MW4 had a concentration of TPH as gasoline at 1 1 mg/1. The laboratory analytical data also indicated that benzene, ethylbenzene and total xylenes were present at concentrations of 120 µg11, 23 µg/l, and 100 µg11, respectively The groundwater sample collected from monitoring well MW5 had no detectable concentrations of TPH or BTEX Soluble lead concentrations in all groundwater samples collected from the five monitoring wells were below the laboratory limit of detection o9zoieal 6