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1 ' been cleaned at the factory and that had been rinsed three times with deionxzed water before being used in a well The water was poured from the bailer into 40-m1 VOA vials, which were then labeled properly and placed in an ice-filled cooler for storage and transport The samples were collected, stored, and transported under chain-of custody procedures The samples were submitted to Pace Incorporated, where they were analyzed for Total Petroleum ' Hydrocarbons as gasoline (TPH-g) by DHS-modified EPA Method 8015 and for benzene, toluene, ethylbenzene, and xylenes (BTEX) by EPA Method 8020 Copies of purge and sample forms are included as Appendix A 1 ' 4. SUMMARY OF RESULTS On 22 August 1993, wells MW1, MW8, MW10, MW13, RWI—RW3, Pl, P2, V2, and V4 ' were purged and sampled The analytical results of the sampling of 22 August are presented in boldface type in Table 1 with results of previous analyses The laboratory analytical report 1s included as Appendix B No petroleum hydrocarbons at concentrations greater than or equal to method detection limits were found in samples collected from well MW13 (farthest downgradient) Well MW 12 was ' not accessible as the lid could not be opened Concentrations of TPH-g in samples ranged from 710 ug/L in MWI to 180,000 µg/L in V2 (Figure 3) Concentrations of benzene ranged from 8 9 pg/L in MWI to 27,000 pg/L in V2 (Figure 4) Excluding the analytical results for the samples of groundwater collected from MW13, petroleum hydrocarbon concentrations were lowest in the samples collected from MWI, P1, and P2, located along the western boundary of the site The concentration of TPH-g in the sample collected from MW8, located ' adjacent to the Shell service station and upgradient of PI and P2, was 52,000 µg/L Petroleum hydrocarbon concentrations of the 22 August sampling are consistent with those of previous sampling events LPH has not been detected in any well since October 1992 ' Water levels in all wells on and off the site (with the exception of wells MW9 and MW 12) were measured on 22 August Measurements and groundwater elevations for 22 August are ' presented in boldface type in Table 1 with previous data The inferred direction of groundwater gradient is to the north-northeast at a magnitude of 0 01 (Figure 5), which is consistent with previous data Groundwater elevations have increased I foot from the ' previous quarter S. WORK PROPOSED FOR NEXT QUARTER ' Water elevations in groundwater monitoring wells will be measured and groundwater samples collected in November 1993 The samples will be analyzed for petroleum hydrocarbons ' The soil vapor extraction and au' sparging system will be constructed and operated by December 1993 73%2/Q8431rX 1 2