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2.3 Groundwater Monitoring On May 17, 1996, IT monitored and sampled groundwater from three existing wells at the ' former Fabncare site Depth to groundwater measurements were taken to all three of the morutonng wells to evaluate groundwater flow and gradient characteristics The depth to groundwater at the site ranged from 35 92 to 36 69 feet below ground surface Based on a pnor ' wellhead elevation survey referenced to a relative surface elevation of 100 feet, groundwater elevations beneath the site ranged from a high of 65 55 feet in MW-2 to a low of 64 15 feet in MW-3 Based on field observations and groundwater surface elevation contours, the surveyed well head elevations may not be accurate, therefore, groundwater elevation data may not reflect ' actual conditions Based on this suspect survey, groundwater flows north at a hydraulic gradient of 0 047 feet/feet Groundwater monitoring data and well construction details for the three ' monitoring wells are summarized in Table 4 ' 2.4 Groundwater Sampling and Analysis On May 17, 1996, the three monitoring wells were purged of at least three well volumes using a decontaminated PVC bailer and sampled Sample Information Forms documenting well monitoring, purging and sampling data are included in Appendix B Groundwater samples were collected from the three wells using a Teflon sampling bailer. packed ' in an iced cooler, and transported under Chain-of-Custody manifest to Sparger Technology,Inc , a California-certified analytical laboratory (#1614) located in Sacramento, California The laboratory analyzed each groundwater sample for TPH-gasoline and BTEX by Modified EPA ' Method 8015/8020 Results of the groundwater sample analyses indicate that petroleum hydrocarbons have impacted the groundwater beneath the site TPH-gasoime is present in groundwater at concentrations of ' up to 770µg/L in MW-3 Benzene was also detected in the groundwater sample from MW-3 at a concentration of 2 2 ,u Low concentrations of toluene, ethylbenzene and xylenes were also ' present in the groundwater Analytical results are summarized in Table 5 and the laboratory reports are included in Appendix C 5 -