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URS Mr. Robert McClellon July 28, 2006 Page 2 FIELD ACTIVITIES The following two sections describe the groundwater monitoring well installation activities and the monitoring activities conducted during the second quarter of 2006. Groundwater Monitoring Well Installation On June 12, 2006,URS installed three groundwater monitoring wells at the World Enterprises site (Figure 1). The wells were installed using a truck-mounted drill rig equipped with hollow-stem augers from Gregg Drilling&Testing, Inc. of Martinez,California. Prior to the installation of the wells,URS obtained concurrence from Mr. Guiardi of SJCEHD of the well locations.Mr. Guiardi was present during the mandatory portion of these activities. The borings were installed in the following order: MW-1,MW-2,and MW-3. A clean California- modified split-spoon sampler fitted with brass liners was utilized to collect soil samples. Soil samples were collected at 5-foot intervals. For each sample interval,the soil from the liners was used to classify the soil. The field geologist logged the soil from each boring using the Unified Soil Classification System. Boring logs for the three wells are attached (Attachment 1). Boring MW-1 was advanced to a depth of 30 feet below ground surface(bgs). Groundwater was initially observed in this boring at 27 feet bgs. The static groundwater surface within this boring was observed to be 18 feet bgs. Boring MW-2 was advanced until auger refusal at 25 feet bgs. Boring MW-3 was advanced to 29 feet bgs. Groundwater was initially observed in this boring at 25 feet bgs.The static groundwater surface within this boring was observed to be 19 feet bgs. After each boring was advanced to its finished depth,a groundwater monitoring well was constructed within the boring. The wells were constructed with 2-inch schedule 40 polyvinyl chloride (PVC)pipe. The screened interval for MW-1 is from 13 to 28 feet bgs (the top of the screen interval was placed 5 feet above the static groundwater surface). The screened interval for MW-2 is from 10 to 25 feet bgs.The screened interval for MW-3 is from 14 to 29 feet bgs (the top of the screen interval was placed 5 feet above the static groundwater surface).For each well,the annulus between the well casing and the boring wall was filled with sand filter pack material from the bottom of the boring to 2 feet above the top of the screen. Two feet of bentonite was placed in the annulus above the sand filter pack. The remainder of the annulus was filled with neat cement. A Christy box was installed at the top of the each well. Construction details of each well are provided in the well's corresponding boring log. Since discolored soil or odorous soil was not encountered within boring MW-1 or boring MW-3,the soil cuttings from these borings were placed on the ground surface of the site, as specified in the approved work plan. For boring MW-2, wood debris was encountered during the advancement of this boring and Mr. Guiardi requested that the soil cuttings from this boring be placed in a 55-gallon drum for appropriate disposal. On June 15,2006, URS developed the three groundwater monitoring wells,using a surge-and-bail method. Borehole water was gently surged back and forth with a bailer,through the well screen and filter pack to loosen fine-grained sediments. The wells were pumped to remove the dislodged material and accumulated fines from within the well.Well development data(e.g., amount of water removed,pH, K:\Wprocess\25532\WorldEnterprise\Quarterly Rpt\2Q06\CovLtrRpt.doc