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PREVIOUS SITE INVESTIGATION RESULTS After removal of three fuel tanks, two that contained gasoline and one that contained diesel fuel, soil samples were taken to determine the impact, if any, of the tanks contents on site LA resources . Canonie Environmental conducted the sampling and analysis of the soil samples . The results of the analyses were as follows . V The sample under the diesel tank found no significant detectable residues of the. contents of the tank (Appendix A) . The sample from under the two gasoline tanks found detectable amounts of total petroleum hydrocarbons and lead (Appendix A) . Of the findings, the lead level was the most significant. Lead under Tank 2 (see Figure 3 ) was reported as 17 mg/kg. Tank 3 (Figure 3) soils were reported to contain 20 mg/kg of lead. These levels exceed the current regulatory guidance (Subchapter 16 , LUFT Manual, DHS-TSCD Decision Tree, etc. ) threshold value of 5 mg/kg that calls for further soil contamination investigation, therefore, the soils under the two gasoline tanks require further evaluation to determine the horizontal and vertical extent of L' lead and petroleum-hydrocarbon impacted soils . The most significant issue is whether the lead is toxic soluble or anic- lead. � L. PROPOSED SOIL CONTAMINATION ASSESSMENT ACTIVITIES La The following is the proposed soil contamination assessment plan. The program involves conducting a bpXing program and removing soil samples to a vertical and horizontal extent where field indications are that no contamination exists . Should the extgQt a roach the depth of first round water the boring would be limited to 10 feet above the capillary fringe of that ground ■• water (conservatively estimated at 5 feet above first water) . The boring program involves utilizing a contract �. driller/equipment operator to develop the necessary boreholes in the vicinity of the contaminated area. The holes proposed for this investigation are mapped on Figure 3 . The equipment �.. proposed is a hollow-stem auger with a split-spoon samplgr forsample removing soil samples . The sampling rationale is as follows. This site has fine- textured soils with associated ji ion ��n e capacities, therefore the lead is ex,pc1;j-_d to have adsorbed onto the soil and La not Penetrated very deeplX. In contrast, the volatile organic -6- Lo LM