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Report:Groundwater-quality Monitoring-December 20-21,2005, 7500 West Eleventh Street, Tracy, CA. Page 10 <br /> r� <br /> PP = 0.79 <br /> The depression in the elevation of the water table due to the presence of floating product <br /> is given by: <br /> 4 <br /> 'W=T (pp/pw) (Equation 1) <br /> Where: <br /> W— the depression of the water table <br /> T = the thickness of floating product in the monitoring well <br /> p,u = the specific gravity of the groundwater <br /> PP= the specific gravity of the floating product <br /> Thus, in the case of the floating product measured in well MW-7 on December 20, 2005: <br /> W=0.03 (0.7911.0) = 0.02 ft. <br /> Accordingly, when drawing the contours shown on Figure 2, the elevation of the <br /> groundwater in well MW-7 was adjusted by 0.02 ft. based on an assumed depth to <br /> groundwater 0.02 ft, higher than that actually measured. <br /> In the period from October 20, 2005, the date on which the depths to groundwater in the <br /> monitoring wells were last measured, to December 20, 2005, the groundwater table in the <br /> majority of wells that are screened in the near-surface aquifer beneath the site rose no <br /> more than .35 ft. In the monitoring wells that are screened in the first aquifer that is <br /> located deeper than the near-surface aquifer (i.e., Monitoring Wells MW-3A and 12A), <br /> the piezometric head rose, on average, only 0.06 ft. In the deepest aquifer that is <br /> monitored at the site (by Monitoring Well MW-313), there was no change in the <br /> piezometric head. <br /> The groundwater elevations presented in Table 1 were used to generate the groundwater <br /> contours shown on Figure 2. <br /> Theoundwater elevations in monitoring wells MW-3A MW-3B and MW-12A were <br /> �" g <br /> not considered when the groundwater contours were drawn because the differences <br /> between the elevations of the groundwater in Wells MW-3, MW-3A and MW-3B and in <br /> MW-12 and MW-12A are usually sufficiently great to indicate that the groundwater <br /> monitored by the shallow well at the locations of each of those well clusters has a <br /> different piezometric pressure from that of the deeper wells in the same cluster. It must <br /> therefore be assumed that, at least locally, the shallow wells monitor aquifers different <br /> from those monitored by the deeper wells. <br /> sic <br />