ARCHIVED REPORTS_PHASE II ENVIRONMENTAL SITE ASSESSMENT

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W G]R. • Southwest, Iliac. excavations made along the fence, F-1 and F-2, ranged from 1.5 to 2 feet deep and determined the debris in that area to be less than six inches thick. Representative soil samples were collected in glass sample jars for analysis from the base of excavations S-3 at a depth of 3 feet bgs and S-6 at a depth of 1.5 feet bgs to provide preliminary data regarding potential impact to underlying soil from the embedded debris. Applicable QA/QC procedures were adhered to during sampling and sample handling. The soil samples were labeled with all pertinent information and packed in a cooler on ice for subsequent delivery to a State of California certified laboratory for analysis. They were transported to the laboratory under appropriate chain-of-custody documentation at the end of the field day. 8.2 Drilling and Soil Sampling A track-mounted, direct push Geoprobe® drill rig contracted through RSI Drilling of Woodland, California was utilized to drill and sample the site. The drilling was conducted on May 14, 15 and 16, 2008. The borings were advanced to approximate depths of 16 to 20 feet bgs in order to allow collection of groundwater grab (no purge) samples from each boring. • Drilling was terminated at the shallowest depth possible to obtain representative groundwater samples. During this investigation, standard practices and procedures for field sampling, as outlined in Publication SW-846, Third Edition, United States Environmental Protection Agency(EPA), were followed. Soil samples were collected for analysis and lithologic characterization in all of the soil borings from depths of 1, 5 and, in some cases, 3 and/or 10 feet bgs. Shallower soil samples were expected to contain higher levels of contaminants due to the historical and ongoing site usage. The 1- and 3-foot samples from each boring were transferred from the hand auger to polyethylene sample sleeves, and immediately sealed with Teflon® film and polyethylene caps. Below the hand-augered depth, the drill rig was used to advance a closed barrel sampler to the desired sampling depth and the piston was unlocked. The sampler, containing 4-foot-long polyethylene Macrocore® sample sleeves, was driven to force soil into the sampler, and then the sampler was retrieved and the sample sleeves extracted. The outer barrel for advancing the direct push soil borings was approximately 2 inches in diameter, and the inner barrel approximately 1.75 inches in diameter. The dual-wall system was utilized to minimize sloughing, maintain boring alignment and minimize vertical migration of potentially contaminated soils or fluids. Portions of the sample sleeves containing soil from the • 704. PRI.05 18 July 21,2008