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1 <br /> 10 Treadwell&Mlo <br /> of under permit to the sanitary sewer The excavation was subsequently backfilled as described <br /> in Section 4 6 (Treadwell & Rollo, 2004b) Analytical results for the soil and groundwater <br /> samples collected at the bottom the excavation are presented in Tables 1 and 2 respectively <br /> 3.2 <br /> Pump Island Excavation <br /> ' During June 2004, soil sampling was conducted in the area of the former pump island and <br /> associated fuel lines to determine if releases of petroleum hydrocarbons had occurred Analyses <br /> indicated that releases had occurred, and soil was subsequently excavated Sidewall <br /> confirmation samples were collected on the north, west, and south walls, and in the bottom of the <br /> ' excavation Analytical results for samples from previous bonngs CSB-4 and CSB-5 contained <br /> no or low petroleum hydrocarbon concentrations, which provided excavation limits for the <br /> northwest and southwest portions of the excavation A sidewall sample was not collected from <br /> the east wall as this was a ramped area required per OSHA regulations Elevated concentrations <br /> 10 of TPH-g at 2,300 milligrams per kilograms (mg/kg), and TPH-d at 700 mg/kg, were detected in <br /> the confirmation sample CPT-EXC-BT-19, which was collected from the northwestern and <br /> deepest part of the excavation (19 feet deep)where the excavation bottom intersected the water <br /> table Because this was the maximum excavation depth possible without shoring the excavation, <br /> impacted soil below 19 feet was not removed The pump island excavation and confirmation <br /> sample locations are illustrated in Figure 2, and analytical results are presented in Table 3 The <br /> final excavation dimensions were approximately 25 feet wide by 22 feet long with an average <br /> ' depth of 10 feet (Treadwell &Rollo, 2004b) <br /> ' 4.0 SOIL AND GROUNDWATER REMEDIATION <br /> The soil and groundwater remediation program in the former pump island and fuel line area <br /> ' included the following <br /> a Shoring for the proposed excavation as shown on Figure 2, <br /> a Excavating and stockpiling soil for sampling and laboratory analyses, <br /> ' 25971024 DGD 4 7 June 2005 <br />