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Groundwater elevations measured December 3, 1993 were approximately one to three tenths of a foot lower than when last measured on September 3, 1993 Groundwater at the site on December 3, 1993 was determined to flow to the northeast ' 3.0 WATER QUALITY SAMPLING AND ANALYSIS Groundwater samples were collected from the five monitoring wells located at the Site on ' December 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 December 1993 groundwater sampling event are shown on Figure 3, and the December 1993 results and previous sampling event results are presented in Table 2 Laboratory analytical data sheets and chain-of-custody records are included in Appendix II. 4.0 ANALYTICAL RESULTS The groundwater sample collected from MW 1 in December 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 5 4 µg/l, 0.55 µg/l and 1 7 µg/l, respectively The groundwater sample collected from monitoring well MW3 had no detectable concentrations of TPH, however, the analytical data indicated that benzene was present at a concentration of 4 4 µg11 Maximum concentrations of benzene in groundwater samples collected in December 1993 were detected in the sample from well N4W4 at a concentration of 380 µg/l However, the groundwater sample collected from monitoring well MW4 had no detectable concentration of TPH as gasoline The laboratory analytical data also indicated that ethylbenzene and total xylenes were present at concentrations of 26 µg/l, and 80 µg/l, respectively 12201ed6 6