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AGE-NC Project No. 99-0559 <br />Page 2 of 13 <br />were hauled from the site to BFI Vasco Road Landfill (BFI) in Livermore for disposal. <br />Following soil excavation and removal, additional soil was excavated for the new UST <br />installation. Soil samples were collected from the enlarged excavation by AGE and four soil <br />samples from the new stockpile for the purpose of characterization for disposal. <br />INITIAL SITE ASSESSMENT <br />On 14, 15, 16 and 17 December 1999, AGE advanced four soil probe borings at the site. <br />Probe boring B1 was advanced in the area of the behind the current store location south <br />of the UST locations to a total depth of 52 feet below surface grade (bsg). Probe boring B2 <br />was advanced in the area between the current USTs to a total depth of 45 feet bsg. A third <br />probe boring, B3, was advanced northeast of the UST area to a total depth of <br />approximately 62 feet bsg. Probe boring B4 was advanced approximately 10 feet north of <br />former UST area to a total depth of 50 feet bsg. Samples were collected at five-foot <br />intervals in each probe boring. Grab groundwater samples were collected from probe <br />borings B3 and B4. The samples were collected utilizing a Geoprobe water sampling <br />assembly fitted with a pre-cleaned one-inch diameter 0.01-inch slotted temporary well <br />screen. <br />The most intensely fuel component-impacted (methyl-tertiary butyl ether: MTBE) soil was <br />in the area of borings B2, MW-2, and MW-3 at depths as great as 65 feet. A significant <br />mass of hydrocarbons was present in the vicinity of well MW-2 from 15 feet to 65 feet bsg <br />and to a lesser degree south of the former USTs, in the area of well MW-3, from 45 feet <br />bsg to 65 feet bsg. <br />INSTALLATION OF MONITORING WELLS <br />On 25 and 26 January 2000, four groundwater monitoring wells MW-1 through MW-4 were <br />installed to a depth of 65 feet bsg at the site. <br />On 27 September and 01 through 03 October 2001, four Continuous Multichannel Tubing <br />(CMT) groundwater monitoring wells MW-5 through MW-8 were installed. Monitoring well <br />MW-5 was installed at the western property boundary, well MW-6 was installed at the <br />southern property boundary, well MW-7 was installed directly east of the UST release and <br />well MW-8 was installed east of the site. The location of CMT wells are illustrated in Figure <br />2. The CMT monitoring wells were designed and constructed utilizing five separate filter <br />pack intervals, from 45-65 feet bsg, 87-100 feet bsg, 125-135 feet bsg, 148-160 feet bsg <br />and 174-185 feet bsg, to characterize groundwater gradient, potential contaminant <br />migration pathways and to assess the lateral and vertical extent of impacted groundwater <br />west and east of the former UST release. <br />Advanced GeoEnvironmental, Inc.