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L L Mr. d Gums �O}' A9170I.OIB January 15, 1996 Page 11 L6.1.2 Soil Characterization.Fanner UST Locations The laboratory analytical results and the results of the field screening of soil samples collected from soil borings B-3, B4, B-5, B-6, B-7, and B-9 at depths of approximately 20 feet BSG do not indicate the presence of PPCs in the soil samples. These findings suggest that PPCs are not present in the soil beneath the former UST locations. 6.13 The laboratory analytical y� L results and the results of the field screening of soil samples collected from soil borings HA- 7, HA-8 and HA-10 at depths of approximately 5 feet BSG do not indicate the presence of PPCs in the soil samples. These findings suggest that PPCs are not present in the soil Ladjacent to the southwestern dispenser island. 6.2 Potential Environmental Effects. As stated in "Subsection 6.1.1", it appears that PPC concentrations exist in soil at approximately 5.feet BSG on the north side and 35 feet BSG beneath the northwestern dispenser island. The vertical extent of PPC migration has not been delimited. Groundwater was estimated to be approximately 45 feet BSG in the Spring of 1991. Thus the potential exist that soils containing PPCs may be in contact with groundwater. 6.3 Additional Studies: The extent of PPC migration in soil has not completely delimited. PPCs are presumed to be present at depths of approximately 5 feet BSG on the north side and 35 feet BSG beneath the northwestern dispenser island. Depth to L groundwater beneath the site is unknown but presumed to be approximately 45 feet BSG. Additional data is needed to delimit the extent of PPC migration in soil and to assess the potential for the soil containing PPCs to have impacted groundwater beneath the site. 7.0 CONCLUSIONS L • The soil profile at the site consists of interbedded strata of sand with silt, silty sand, sandy clay, well graded sand, sand with gravel, and poorly graded sand to a depth of 36.5 feet BSG the greatest depth explored; • PPCs were present in the soil samples collected from sampling locations #3 and #4 (on the north side of the northwestern dispenser island) on April 22, 1994 at 5 feet BSG; • TPH-D is present in the soil sample collected at approximately 35 feet BSG from soil boring B-1 at a location which roughly corresponds to the center of the northwestern dispenser island; • PPCs were not detected in the six soil samples collected at a depth of approximately 20 feet BSG from beneath the former UST locations; L