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Beck Property,Tracy,CA November 1988 Site Investigation <br /> Five surface (0 to 6-inch depth) soil samples (background) were collected on Tracy <br /> School District property immediately north of the Beck property. These samples <br /> were identified as SS-6 through SS-10 and delivered to the laboratory with <br /> instructions for compositing and analysis. <br /> Subsurface Soil Investigation and Sampling (within reservoir) <br /> Eight auger borings (AB-1 through AB-8) were positioned within the perimeter of <br /> the oil reservoir for the purposes of soil collection, soil observation, soil logging, and <br /> reservoir depth confirmation. Soil samples were retrieved with a split spoon sampler <br /> and managed, observed, and logged by an AEMC staff geologist. Refer to the Soil <br /> Boring Logs presented in Appendix 2 of this report. <br /> Soil samples collected at the 2-foot, 4-foot, 6-foot and bottom depths of each auger <br /> boring were documented on Sample Management Records (Appendix 3) and <br /> delivered under chain-of-custody to the laboratory. Splits of all soil samples were <br /> made available to the onsite State DHS representative. AEMC was unable to field <br /> analyze soil samples from each auger boring due to a malfunction with the <br /> Photoionization Detector. The Soil Boring Logs identify the depth of the concrete <br /> reservoir bottom at each boring location. <br /> Subsurface Soil Investigation (outside reservoir) <br /> AEMC deviated from the Workplan and positioned four auger borings (AB-A, AB- <br /> B, AB-C, and AB-D) outside the perimeter of the oil reservoir. Reason being, in the <br /> process of augering the borehole for the deep monitoring well (BD-5), AEMC <br /> encountered oil in the saturated zone 12.5 to 15-foot depth. Due to the detection of <br /> oil outside the reservoir, AEMC decided to move the shallow monitoring well (BD- <br /> 4) location approximately 150 feet to the northwest (downgradient groundwater <br /> direction). In addition, AEMC decided to exchange the time and resources made <br /> available by not establishing the deep monitoring well (BD-5) and to proceed with <br /> the four auger borings, identified above, in an effort to determine the extent of oil <br /> contamination. <br /> rt�c-o,iz> Page 6 <br />