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Table 1 summarizes the results of the laboratory analyses Cham-of-custody documentation and ' laboratory data sheets are provided in Appendix 11 ' RESULTS OF GROUNDWATER ANALYSIS On Friday May 8, 1992, all the monitoring wells on site (MW1, MW2, and MW3) were tmonitored for free product No free product was detected in any well After well development and purging, groundwater samples were collected and analyzed for BTEX and TPHG ' Dissolved petroleum hydrocarbons as TPHG and benzene were present above method detection limits in wells MW 1 (S 1 ppb/7 4 ppb), MW2 (460 ppb/38ppb), and MW3 (1100 ppb/120 ppb) ' Xylenes were also detected in MW3 (0 9 ppb) No other BTEX constituents were detected Table 2 summarizes laboratory analysis results Cham-Of-custody documentation and laboratory ' data sheets are provided in Appendix 11 ' GROUNDWATER GRADIENT AND FLOW DIRECTION On March 12, 1992, depth to water readings were collected from well MWI and from the irrigation wells, one to the north (IRR3), and the well immediately south (IRR2) of the monitoring well The irrigation wells were reported to have been unused for some time prior ' to monitoring Access to irrigation well 2 was difficult, the data was considered to be suspect and was not honored Irrigation well 3 data, which indicated a northerly gradient, and other gradient data from nearby sites was utilized for new well placement ' Subsequent to the installation of MW2 and MW3, depth to water readings were collected on May 8, and May 20, 1992 Groundwater gradient, calculated utilizing the May 20, 1992 data, is to the northeast at 0 0008 ft/ft or 4 22 ft/mile (Figure 4) Appendix 11 contains Well Development Logs and monitoring data 1 CONCLUSIONS Soil sampling during the removal of two underground storage tanks at the site to in November, 1989 indicated that an unauthorized release of gasoline had occurred This is presumed to have taken place during September, 1989 ' R 052992 LF 8