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<br /> Fayette Manufacturing Corporation, 7675 West Eleventh Street, Tracy, California, dated
<br /> November 7, 1995.
<br /> On September 24 and October 2, 1996, Smith Technology supervised the advancement of nine
<br /> -7 and FPB-1 and FPB-2 at the locations shown on Figure 2. Soil
<br /> soil borings, SB-1 through SB
<br /> boring logs are contained in Appendix A. The borings were advanced utilizing direct push
<br /> technology and soil, soil vapor, and groundwater samples were collected for chemical analyses.
<br /> Analytical results of the soil, soil vapor, and groundwater samples collected delineated the
<br /> horizontal extent of petroleum hydrocarbon contamination in the vicinity of the former gasoline
<br /> UST locations. Analytical results for chemical analysis are summarized in Tables 1, 2, and 3.
<br /> {_==, During this phase of work, the collected soil, grab groundwater, and soil vapor samples were also
<br /> submitted for geophysical analysis to determine if natural biodegradation of petroleum
<br /> constituents was occurring beneath the site. Soil samples from significantly different lithological
<br /> units encountered during drilling were submitted for the following geophysical analyses: falling
<br /> head permeability, percent moisture, porosity, dry bulk density, soil pH, percent organic content,
<br /> ' and carbon to nitrogen to phosphorus (C.N:P) ratios. Grab groundwater samples were field
<br /> -� monitored for oxidation-reduction potential and submitted for laboratory analysis of carbon
<br /> dioxide, alkalinity, nitrate, sulfate, and ferrous iron. Soil vapor samples were submitted for
<br /> laboratory analysis of oxygen, carbon dioxide, nitrogen, and methane. Analytical results of
<br /> geophysical analysis are summarized in Tables 1, 2, and 3. This phase of work is detailed in Smith
<br /> Technology Corporation's Additional Soil and Groundwater Report, Fayette Manufacturing
<br /> Corporation, 7675 West Eleventh Street, Tracy, California, dated January 31, 1997.
<br /> Since the installation of the groundwater monitoring wells in July 1995, Smith Technology
<br /> Corporation has conducted nine quarterly groundwater monitoring events. The groundwater
<br /> gradient has been generally north-northwest during these monitoring events. Groundwater
<br /> elevation data is summarized in Table 4,
<br /> 2.0 GROUNDWATER MONITORING
<br /> 221 Fourth Ouarter 1997
<br /> ` ATC Associates personnel performed the fourth quarter 1997 groundwater monitoring of
<br /> monitoring wells MW1, MW2, and MW3 on December 31, 1997. Field work consisted of
<br /> measuring depth-to-water levels in all wells and collecting groundwater samples from all wells and
<br /> E =; submitting groundwater samples for laboratory analysis. On December 31, 1997 groundwater
<br /> •=� flow was to the northwest at a gradient of 0.003 ft/ft. The groundwater gradient for December
<br /> 31, 1997 is shown on Figure 3.
<br /> J Groundwater samples were collected from monitoring wells MW-1, MW-2, and MW-3. Prior to
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<br /> collection of groundwater samples a minimum of three well casing volumes were purged. The
<br /> depth-to-water, pH, electrical conductivity, and temperature were measured and allowed to
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