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fractions of gasoline can move in a vapor state. With the high relative porosity of the site' s :=fine-textured. soil, even with a high moisture content the volatile organics have likely moved i farther than the lead. Therefore, utilizing the presence or absence of the volatile petroleum hydrocarbons for contamination indication should be sufficiently conservative to delineate the lead contaminated zone at the site. Confirmation would be provided by the laboratory analyses, of the soil samples . Soil samples would be obtained in the following manner. Commencing at the bottom of the�foriginal excavation under the i removed tanks, camples would betaken every five feetiuntil two } consecutive samples do not have ' cations of contamination. Should the sam les continue t o with depth the last s le would be removed at ;; t 1 feet above the anticipated first ground water zone. Soil samples would be obtained by pushing a split-spoon sampler with appropriate liners below the lowest penetration of the hollow-stem flight auger. The split-spoon and liners would be prepared and handled according to a. .sampling protocol developed for the site taking into account the materials to be investigated and the materials in the sampler. The sampling protocol is included in Appendix B attached'to this report. Samples obtained from the above. program would be stored in an ice chest with non-contaminating ice (dry ice or distilled water ice j in clean polyethylene plastic) and shipped to the consulting laboratory for analysis . Chain.,of custody forms will be transmitted with the clearly labeled samples . Examples of the labels and forms are included in Appendix B. The samples will be analyzed for total petroleum hydrocarbons, total leadl,and soluble lead. ` revious analyses indicated the levels? o!' BTX and EDB arm j T below thresholds of concern, therefore there is .no apparent �^ reason to analyze }for these parameters . AO LL) l �' Contaminated drilling spoils will be- stored on-site in a = 5, � designated area for eventual disposition in accordance with an �� approved soil remedial plan. After the borings are drilled to the needed depth they will be filled: with c4ea or !a nite rout de2ending on the source and availability of native soil. If the requirements cannot be met by the native soil or local agencies prefer clean. bentonite, bentonite will be used. Based on the existing information, the local native clays are an excellent boring closureEmaterial.