ARCHIVED REPORTS_SITE CHARACTERIZATION REPORT 1999

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Treadwell&Rollo ' ten-foot spacing. TC results indicated that two anomalies were present while several VMG anomalies were detected. 3.2.2 Soil and Grab Groundwater Sampling On 14 and 15 September 1999, Precision Sampling, Inc. (Precision) of Richmond, California used a backhoe to dig exploratory pits and trenches to a depth of 4 to 10 feet at the geophysical anomalies. Figure 4 shows the TP locations. An additional excavation was located in the central portion of the site. This area was excavated to a depth of 10 feet bgs. Buried metal, construction debris, and utility lines were encountered in the trenches; however, no evidence of existing USTs was found. Test pits 2ATP-3 through 5 were excavated to ten feet at the locations shown on Figure 4. Soil samples were collected at the locations shown on the test pit logs in Appendix C. ' On 17 September 1999, Precision used the SD-1 direct push rig to collect soil and groundwater samples. Soil borings 2AB-1, 2AB-2, and 2AB-3 were pushed to a depth of 10 feet and 2AB-4 wasp ushed to a depth of 52 feet. Soil samples were collected at the depths shown on the boring ' logs in Appendix C. A groundwater grab sampling was collected at boring 2AB-4. On 11, 12, and 13 October 1999, THF Drilling,Inc. (THF) of Fontana, California installed ' monitoring wells under the direction of Treadwell &Rollo. Borings 2AMW-12 through 2AMW-15 were drilled to depths of approximately 30 feet. Soil samples were collected for laboratory analysis at the locations shown on boring logs in Appendix C. 3.2.3 Groundwater Monitoring Well Development and Sampling On 2 September 1999, Blaine Tech Services Inc. (Blaine Tech) of San Jose, California, collected groundwater from monitoring wells MW-1, MW-5, MW-6,MW-8, and MW-9 and a duplicate sample (DUP) from well MW-1. Monitoring wells MW-2, MW-4 and MW-7 could not be located and monitoring well MW-3 had been damaged, preventing sampling. 9 25970119.DGD 13 December 1999