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KLEINFELDER i 3 FIELD ACTIVITIES 3.1 SOIL-GAS SURVEY On March 1, 1990, a soil-gas survey was conducted by Tracer Research. An attempt to extract soil-gas was made at 14 locations, A through N, as shown on Plate 2. In most locations, the impermeable nature of the soil did not allow gas to be extracted. For this E , reason,the probe was pushed one to two feet deeper and ground water was exicracted. Soil gas was extracted at depths of three feet and four feet at locations E and F, respectively. Ground water samples were extracted from depths of seven feet at locations B, C and E; eight feet at locations F,11, K, M and N; and at 10, 11 and 13 feet at locations I,A, and D respectively. After the sample was extracted, the holes were filled with bentonite pellets, and distilled water was poured into the holes to hydrate the bentonite and seal off the - holes. Soil-gas and water samples were analyzed on site by GC/FID. The mobile laboratory,GC/FID, is not a state certified for these analyses and was used to serve as a preliminary screening tool. To obtain quantitative data, information from the soil-gas survey is used to collect confirmatory samples from sail borings, which are T submitted to a state certified Iaboratory for analysis. Soil-gas survey protocol and results are presented in Appendix B, "Shallow Soil Gas and Ground Water Investigation." - 3.2 SOIL BORINGS On March 6, 1990, three soil borings were drilled at the Weber Avenue Site. Scil borings were placed at Iocations designed to confirm the boundaries of potentially affected soil as indicated by the soil-gas survey. Soil borings were drilled to an approximate depth of 7.5 A. feet and soil samples were collected at depths of 1.5 feet, 4.5 feet, and 7.5 feet (Table 1). Generally fine silty sand or silty clays were encountered. Locations of the soil borings are shown on Plate 3. DrilEng protocol is described in Appendix13. -- -- - --- On the basis of field observations and qualitative field screening, one of the multiple —- ------- --— ` samples collected from each boring was selected for chemical analysis. Table 2 is a log of l� F15-90-101 3 copyright 1990 Kteinfetder, Inc.