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ENSR ; ' The nearest well to the site is a USGS water monitoring well located approximately 800 feet northeast (downgradient)of the site The well's submersible pump is approximately 160 feet bgs (AGS, 1990) Telephone conversations with the USGS regarding this well determined that USGS wells are generally installed for monitoring and not water supply purposes Given the depth of the regional productive interval and the predominance of clay deposits in the overlying stratigraphic units, it is ENSR's opinion that there is no strong connection between the site and the aquifer from which local water supply wells withdraw their water ' 3.2 Sensitive receptors survey ENSR conducted a sensitive receptors survey for the site and surrounding area to identify such things as ' schools, hospitals, drinking water supplies that could be affected by conditions at the site The data was obtained through the services of Environmental Data Resources, Inc (EDR), in Milford, CT in two reports which are included in Appendix A These reports are titled EDR Offsite Receptor Report (Inquiry Number ' 01640841 2r) and EDR GeoCheck®Report(Inquiry Number 01640841 1 r) According to the information provided by EDR, there are approximately 21,022 people living in a one-mile radius of the site, including 44 institutions— 11 day care centers, three medical centers, six nursing homes, ' 15 schools, six hospitals, two colleges, and one arena Within a '/4-mile radius of the site there are two institutions—the EI Dorado Elementary School (approx 118 mile south in a crossgradient location) and the Grace United Methodist Head Start Daycare (approx '/4 mile southwest in an upgradient location) Refer to EDR's Receptor Map within the Offsite Receptor Report of Appendix A for more detail Nine water wells were identified with a '/4 mile radius of the site Eight wells are located southwest and upgradient of the site in very close proximity to one another These eight water wells include three irrigation wells, one destroyed well, two active treated water wells, and two active raw water wells The-eghth-well (EDR ID # USGS 3221904) is located northeast and downgradient of the site That well is identified as a single well with a depth of 405 feet and a well depth of 400 feet It is unknown from the EDR report if the USGS well is a drinking water well or not ENSR contacted the USGS and consulted the Department of Water Resources website regarding the well and its purpose The well was not listed as a drinking water or irrigation well, and a contact at the USGS stated that wells belonging to them are generally not used for production, but for monitoring purposes (DWR, 2006) Refer to EDR's Physical Setting Source Map within the GeoCheckO Report of Appendix A for more detail 3.3 Contaminant distribution to soil Soil samples have been collected from the site by others during the excavation of the former USTs and the advancement of the numerous soil borings both on-site and off-site During the removal of the former USTs in 1983, approximately 1,100 to 1,350 cubic yards of soil was excavated and removed from the Site As stated previously in Section 2 2, post-excavation soil sample results from the former gasoline USTs cavity reported residual levels of TPH (maximum of 18 ppm), benzene (maximum of 1 72 ppm), toluene (maximum of 5 01 ppm), ethylbenzene (maximum of 0 58 ppm), and total xylenes (maximum of 3 83 ppm) These maximum concentrations were detected in sidewall soil samples Concentrations in the soil samples from the bottom of the excavation were less Soil sampling and analysis performed during the advancement of well NP-1 (east of the former eastern pump island) in January 1999 and boring B-5 (immediately south of the former eastern pump island) in January 1988 reported residual concentrations of TPHg and BTEX in soil at these locations The impacted soil at boring B-5 was in the vadose zone at depths of 15 5 and 20 5 feet bgs, while the impacted soil at well 3-2 06