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0 Kennedy/Jenks/Chilton Mr. Keith M. Casto, Esq. Hoge, Fenton, Jones & Appel , Inc. 12 September 1990 Page 2 SOIL SAMPLE COLLECTION Ten shallow soil borings ranging in depths from two to nine feet were drilled at the site on 23 August 1990 for the purpose of soil sample collection. Nine borings were drilled within the vineyard and one boring was drilled within the almond orchard where access for the drill rig was allowed. Nine borings, rather than eight, were drilled in the vineyard because it did not initially appear that access for the rig in the almond orchard would be possible. However, it was possible to mobilize to a location in the orchard, so an additional boring was drilled. Figure 2 shows the locations and depths of the borings drilled. The borings were drilled using a truck-mounted drill rig utilizing six-inch hollow stem augers. Soil samples for laboratory analysis and lithologic description were collected in two-inch by six-inch brass liners inserted into a California-modified split-spoon sampler. The sampler was driven into the soil at the appropriate interval using 140-pound drive-hammer free falling approximately three feet. The sampler was extracted from the boring and one liner was retained for laboratory analysis. The selected brass liner was covered on both ends with a Teflon sheet and plastic cap. The sample was labelled as to date, sample location, depth, sampler's initials and placed in a chilled ice chest. Chain-of-custody forms were completed and accompanied the samples to the Kennedy/Jenks/Chilton laboratory in San Francisco, California. A copy of the chain-of-custody form is attached to this letter (Attachment A) . Soil from the other liners was lithologically described by a Kennedy/Jenks/ Chilton geologist using the Unified Soil Classification System (USCS) . Soil descriptions, including the USCS group symbol and group name, are provided in Table 1. Sampling equipment, including the augers, samplers and liners were steam cleaned prior to use and between each boring to minimize the potential for cross contamination. Each boring was backfilled with bentonite in accordance with SJCEHD requirements. The backfill procedure consisted of filling the boring with bentonite chips and hydrating the bentonite with potable water. LABORATORY ANALYSES AND RESULTS The soil samples were analyzed in the laboratory for DBCP using State of California method AB1803. The sample from boring B-2 was not analyzed because this was an additional boring drilled when it appeared that boring B-10 could not be drilled. C