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chain-of-custody procedures to MBT Laboratories, a state certified laboratory, for analysis Analytical results of the June 1993 groundwater sampling event are shown in Figure 3, and the June 1993 results and previous sampling events results are presented in Table 2. Laboratory analytical data sheets and chain-of-custody records are included in Appendix H. 4.0 CONCLUSIONS The groundwater sample collected from monitoring well MW 1 had concentrations of total petroleum hydrocarbons (TPH) as gasoline at a concentration of 0.69 milligrams per liter (mg/1) and toluene, ethylbenzene and total xylene at concentrations of 6.0 micrograms per liter (µg/l), 1 1 µg/l and 1 1 µg/l, respectively. 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 9.5 µg/l, 0.92 µg/l and 6 9 µg/1, 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 78 µg11 Maximum concentrations of petroleum hydrocarbons in groundwater samples collected in June 1993 were detected in samples from well MW4. The groundwater sample collected from monitoring well MW4 had a concentration of TPH as gasoline at 0.84 mg/l. The laboratory analytical data also indicated that benzene, ethylbenzene and total xylenes were present at concentrations of 430 ,ug/l, 20 µg/l, and 91 µg11, respectively The groundwater sample collected from monitoring well MW5 had no detectable concentrations ' of TPH or BTEX Total lead concentrations in all groundwater samples collected from the five monitoring wells 1 were below the laboratory limit of detection. McLaren/Hart believes that the increase in concentrations observed during the June sampling round may be due to chemicals in soil dissolving in groundwater The groundwater has risen approximately four feet since the November 1992 sampling and is in the zone (approximately 25 feet below grade) where soil contamination has been encountered Data obtained during the next sampling rounds will be carefully evaluated in order to determine the extent of groundwater impact mosicd2 6