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SOIL SAMPLING Soil samples will be collected a five-foot intervals and at obvious lithologic changes. Soil samples will also be collected below the water table from proposed soil boring SB-deep. The first groundwater table is at approximately 10 feet below grade. All soil samples will be screened in the field with the use of a PID. The soil sample with the highest PID reading, one soil sample at the 10 foot interval , and the one bottom soil sample from each boring (20 foot sample) will be submitted for the three proposed soil boring MW-10 through MW-12. At.a minimum, at least five soil samples below 20 feet bg will be submitted from SB-deep under chain-of-custody, to a state-certified laboratory for analysis of: a)TPH, as gasoline; TPH, as diesel, and TPH, as kerosene by modified EPA Method 8015; b) BTEX and MTBE by EPA Method 8020; c) five oxygenates, DCA and EDB by Method 8260. All drill cuttings will be temporarily stockpiled on site, under and on plastic sheeting, pending receipt of the analytical results. GROUNDWATER SAMPLING The three new groundwater monitoring wells will be developed, sampled, and the top of the casing elevations will be surveyed referenced to the existing wells according to the Apex Standard Operating Procedures (SOP) included in Appendix B. Apex will also sample the existing nine wells (MW-1, MW-2, MW-3, MW-4A, MW-5, through MW-9) at the same time. In addition, Apex will collect a groundwater sample from the residence located just east to the site, which is located on the northeast corner of F Street and Sixth Street. All 13 groundwater samples will be submitted, under chain-of-custody, to a state-certified laboratory for analysis of. a)TPH, as gasoline; TPH, as diesel; and TPH, as kerosene by modified EPA Method 8015; b) BTEX and MTBE by EPA Method 8020; c) five oxygenates, DCA and EDB by Method 8260. PILOT TEST Apex proposed to implement a pilot test in a report entitled First Quarterly Groundwater Monitoring Report dated February 18, 2000. The County agreed with Apex's recommendation to conduct the pilot test in a Ietter dated March 9, 2000 (Appendix A). The following section discusses the proposed pilot test in detail. Soil vapor extraction (SVE), utilizing well MW-8 appears to be best suited as a remedial alternative for the site. SVE was utilized in the past successfully at the site. The vadose or smear zone is comprised of medium grained, well sorted sand that is overlain by silty clay. This site geology is ideal for SVE. Apex recommends SVE based on the following reasons: • Petroleum impacted groundwater has been detected at downgradient monitoring wells (MW- 8 and MW-9) during the last two monitoring events.