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GeologccdTec"CsI" Page 2 George's Service Soil Excavation Report Project No 425 3 January 28, 2002 ' discretely screened, monitoring wells and one deep discretely screened, monitoring well Quarterly groundwater monitoring reports has been submitted throughout the project ' 3.0 SOIL EXCAVATION The observations made and issues encountered during this work are discussed below Soil Excavation and Backfill On July 23, 2001, Del-Tech Geotechnical Support Services (Del-Tech) and Geological Technics Inc (GTI) personnel mobilized to the site to begin excavation operations The area around the proposed excavation was secured by placing concrete K-rail along Durham Ferry Road and Highway 33 Orange poly security netting fence was placed all the way around the excavation on top of the K-rail The excavation began near the northern corner of the building, around MW-102 and MW-202, and progressed to the south and west A Case 580K backhoe was used to perform the excavation ' The clean overburden was removed and piled around the limits of the excavation to help secure it Contaminated soil was encountered at approximately 5-feet below ground surface ' (bgs) and was stockpiled in the southern portion of the property, south of MW-4 (refer to Figure 1) On July 24, 2001, Del-Tech and GTI personnel mobilized to the site to continue excavation operations Overnight approximately 15-inches of water bad accumulated at the bottom of the excavation and floating product was observed on nearly half the surface Excavation continued around MW-1021202 to a depth of 13 5-feet bgs In the working area, OVM readings ranged between 1 5 and 10 ppm It was decided to order an excavator with a 1- cubic yard bucket for the next day On July 25, 2001, Del-Tech and GTI personnel mobilized to the site to continue excavation operations Excavation proceeded to within approximately 30-feet of the fog line on Highway 33 MW-2 and MW-5 marked the northern boundary of the excavation The southern wall of pit began to collapse under the building and was shored with ' uncontaminated overburden Total depth of excavation was approximately 11-feet bgs Stockpiled soil was placed on plastic located in front of the old residence, south of the station ' Samples were collected at random spacing through the stockpiled soil by driving a clean brass tube into the soil The ends of the tubes were then covered with Teflon and plastic caps The tubes were labeled, placed in a chilled cooler, and a chain of custody was filled ' out and the samples submitted to Sherwood Laboratories in Hilmar for analysis Data Table 1, Appendix A summarizes all soil test results collected associated with the excavation Laboratory Data Sheets are included in Appendix B ' On July 26, 2001, Del-Tech and GTI personnel mobilized to the site to continue excavation operations The backhoe was used to expose fresh sidewall surfaces in the excavation pit ' and a total of ten samples were collected for analysis The excavation pit was then backfilled with 1 5-inch drain rock to a depth of 5 feet bgs and compacted with a vibrating compactor For use in vapor extraction, two 4-inch diameter