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July 29, 1999 Page 2 The UST excavation was approximately 35 feet by 40 feet by 15 feet deep. Six soil samples were collected from beneath the removed USTs on April 7, 1999. The excavation was deepened beneath the center of the western tank to approximately 18 feet below ground surface (bgs) and one additional soil sample was collected. Soil sample locations are shown on Figure 3. Sample designations, collection depths, and the results of laboratory analyses performed on these samples are presented in Table 1. The soil samples collected at the maximum extent of excavation in the area of the removed USTs, total petroleum hydrocarbons quantified as gasoline (TPH-g),benzene and methyl tert-butyl ether (MtBE),were all below method detection limits (ND). Analysis for the fuel oxygenates tert-butanol, MtBE,di-isopropylether(DIPE), ethyl tert- butyl ether (EtBE), tertiary-amyl-methyl ether(TAME) and tert-butanol was performed for the soil samples T1-C, T2-C and T3-C. The analysis reported MtBE in sample T3-C at l 5 feet. However,the sample collected at 18 feet was ND. No other oxygenates were detected. Field and laboratory procedures are presented as Attachment B. The certified analytical reports and chain-of-custody documentation are presented as Attachment C. DISPENSER ISLAND AND PIPING REMOVAL Soil samples were collected from beneath the removed dispensers and associated piping on April 8, 1999. Mr. Infurna of SJCEHD whitnessed soil sampling activities. Impacted soil was reported in samples L-2, L-5,L-6, L-10, D-1, D-3,D-4,D-6 and D-7. Soil sample locations are shown on Figure 3. Sample designations, collection depths, and the results of laboratory analyses performed on these samples are presented in Table 1. During additional excavation activities unidentified fiberglass piping was encountered. The plumbing was removed and soil samples (L-8 through L-11)were collected at the direction of Mr. Infurna. REMEDIAL ACTIVITIES • April 7, 1999—initial remedial activities included source removal of obviously impacted soil to a depth of approximately 18 feet bgs at the center of the western fuel tank. Removed soil was comprised of excavated and over-excavated material. Soil sample locations are shown on Figure 3. April 8, 1999 —Additional remedial activities included source removal of obviously impacted soil in the area below dispenser and product lines. Soil at the location of sample D-1 was excavated to approximately 5 feet bgs. A concrete pad restricted lateral extent of excavation. During excavation of impacted soil,unidentified fiberglass piping was found. Samples were collected from the bottom and side of the excavated area. Soil sample locations and the extent of excavation for this event is shown on Figure 3. 9110111A/Report