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3.0 SOIL REMEDIATION INFORMATION <br /> The asoline hydrocarbons detected in soil beneath the northern end of former Tank 2 were not <br /> 9 <br /> remedtated The vertical extent of impacted sod has not been defined <br /> To remediate impacted soil from the vicinity of the west dispenser, approximately 60 cubic yards <br /> of sod were excavated and aerated on-site According to the PHS/EHD inspector's notes, this <br /> excavation extended from the west dispenser approximately 15 feet south and 21 feet east The <br /> western part of the excavation was extended to approximately 7 feet bgs and the eastern part of <br /> the excavation was deepened to approximately 12 feet bgs Although no detail is provided in the <br /> inspector's notes, the eastern part of the excavation was probably deepened to 12 feet to <br /> remove visibly impacted soil along the former product distribution piping trench No soil samples <br /> were apparently collected for analysts from the floor or side-walls of this excavation <br /> Based on the results of the soil samples collected from the two soil borings (D-1 and D-2) <br /> impacted soil appeared to be limited to shallow subsurface sod in close proximity to the west <br />' dispenser island Although no excavation floor or side-wall samples were collected for analysis, <br /> the excavation of impacted soil was completed to the satisfaction of the PHS/EHD inspector <br /> A total of approximately 260 cubic yards of soil was excavated, stockpiled, sampled, aerated, re- <br /> sampled and finally disposed of on site The initial 200 cubic yards was generated during the <br /> UST removal operations and the remaining 60 cubic yards was generated during the over- <br /> excavation of the west dispenser area <br />' From the eight discrete soil samples collected from the original 200 cubic yard soil stockpile, <br /> only three samples contained detectable concentrations of TPH-as-gasoline (up to 120 mg/kg), <br /> ttoluene (up to 1 3 mg/kg) and xylenes (up to 4 9 mg/kg) Ethylbenzene was only detected in one <br /> soil sample at a concentration of 0 005 mg/kg Benzene was not detected in any of the sod <br /> samples All eight soil samples contained concentrations of MTBE The maximum <br /> concentration of MTBE was detected at 3 6 mg/kg The other four oxygenate compounds were <br /> not detected in any of the eight soil samples After approximately eight months of passive <br /> aeration, the stockpiled soil was re-sampled In this single two-in-one composite soil sample, no <br /> concentrations of TPH-as-gasoline, BTEX or oxygenates were detected Based on these <br /> results, the soil stockpile was spread out in the southern part of the site Results of the sod <br /> stockpile samples are summarized in Table 3 and the laboratory reports are included in <br /> Appendix A <br /> • 5 <br /> 1 <br /> 1 <br />