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a ofunder permit-to the sanitary sewer-The excavation was subsequently backfilled as describe in Section 4.6 (Treadwell&Rollo, 2004b). Analytical results for the soil and groundwater samples collected at the bottom the excavation are presented in Tables 1 and 2 respectively. 3.2 Pump Island'.Excavation•- During June 2004, soil sampling was conducted in the area of the former pump island and associated fuel lines to determine if releases of petroleum hydrocarbons had occurred: Analyses indicated that releases had occurred, and soil was subsequently excavated. Sidewall confirmation samples were collected on the north,west, and south walls, and in the bottom of the excavation. Analytical results for samples from previous borings CSB-4 and CSB-5 contained no or low petroleum hydrocarbon concentrations,which provided excavation limits for the northwest and southwest portions of the excavation. A sidewall sample was not collected from the east wall as this was a ramped area required per OSHA regulations. Elevated concentrations of TPH-g at 2,300 milligrams per kilograms(mg/kg), and TPH-d at 700 mg/kg,were detected in the confirmation sample CPT-EXC-BT�19,,which was collected from the northwestern and deepest part of the excavation(19 feet deep)where the excavation bottom intersected the water table. Because this was the maximum excavation depth possible without shoring the excavation, impacted soil below 19 feet was not removed. The pump island excavation and confirmation sample locations are illustrated in Figure 2, and analytical results are presented in Table 3. The final excavation dimensions were approximately 25 feet wide by 22 feet long with an average depth of 10 feet(Treadwell&Rollo, 2004b). 4.0 SOIL AND GROUNDWATER REMEDIATION The soil and groundwater remediation program in the former pump island and fuel line area included the following: • Shoring for the proposed excavation as shown on Figure 2; • Excavating and stockpiling soil for sampling and laboratory analyses; 'Y 25971024.DGD 4 7 June 2005