specs

Geotechnical Investigation South River Place, Gasser Drive, Napa 29 December 2010
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the samples for Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) using EPA Test Method
8015M and for CAM 17 Metals. The test results indicate all constituents tested are either nondetect
or are below the Not To Exceed Gasser Site Reuse Criteria. In addition, the four samples
were transported to our laboratory for classification testing consisting of grain size analysis and
Atterberg Limits. Based on our testing, the stockpile soils consist of brown to dark brown,
moderately expansive sandy clay.
Field Investigation
Our recent field investigation was performed on 17 and 18 December 2010 and included a
reconnaissance of the site and the drilling of 7 additional exploratory test borings at the
approximate locations shown on Figure No. 4, “Site Plan” included in Appendix A. The boring
logs include approximate elevations based on a FGA Preliminary Grading Plan.
The borings were drilled to depths of 28.5 to 50 feet below the existing ground surface
(including stockpile). The drilling was performed with truck-mounted Mobile B24 drill rig using
power-driven, four-inch diameter, continuous flight augers. Visual classifications were made
from the auger cuttings and the samples in the field. As the drilling proceeded, relatively
undisturbed tube samples were obtained by driving a 2.5-inch O.D., California split-tube sampler,
containing thin brass liners into the boring bottom. Disturbed samples were obtained by driving a
2-inch O.D., split-barrel sampler into the boring bottom in accordance with ASTM D1586. The
sampler was driven into the in-situ soils under the impact of a 140 pound hammer having a free fall
of 30 inches. The number of blows required to advance the sampler 12 inches into the soil were
adjusted to the standard penetration resistance (N-Value). When the sampler was withdrawn from
the boring bottom, the brass liners containing the relatively undisturbed samples were removed,
examined for identification purposes, labeled and sealed to preserve the natural or in-situ moisture
content. The samples were then transported to our laboratory for testing. Classifications made in
the field were verified in the laboratory after further examination and testing. The stratification of
the soils, descriptions, location of undisturbed soil samples and standard penetration resistance
are shown on the respective “Logs of Test Borings” contained within Appendix A.
Laboratory Investigation
The laboratory testing program was directed towards providing sufficient information for the
determination of the engineering characteristics of the site soils so that the recommendations
outlined in this report could be formulated. The laboratory test results are presented on the
respective “Logs of Test Borings” and data sheets in Appendix A. We have also reviewed the
previous lab test results (included in Appendixes B and C) as part of this report.
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KC ENGINEERING COMPANY Project No. VV3200 Page 8 of 123