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�. Site Characterization:Clover_ addle School,51 East Beverly Place, Tracy, CA, - Page 6 bottom of the four-foot sampling depth interval. Soil samplings from the borings were identified by the nominal linear distance down the boring from which they were recovered, as measured by their position in the split-spoon liner from which they were cut. Following sample recovery, each sample liner was cleaned externally, closed with tightly fitting plastic caps and the caps were secured with adhesiveless tape. Each sample liner was then labeled for identification, entered into chain- of-custody control and packed on chemical ice in an electrically-cooled box for transport to Chromalab lnc.'s (Chromalab) laboratory in Pleasanton, California within 4 hours of their recovery from the subsurface 3.2.3 Groundwater Sampling Groundwater samples were recovered from each cased probe hole using a %z- inch diameter bailer. The recovered water was decanted to completely fill clean glassware containing a pre-dispensed preservative supplied by the laboratory. The sample vials were then tightly closed, labeled for identification, entered into chain-of-custody control and packed on chemical ice for transport in an electrically-cooled box to Chromalab's laboratory where they were received within 4 hours of their recovery. 3.2.4 Depths to Groundwater Following recovery of groundwater samples,the water level in each probe hole was allowed to stabilize for at least one hour before a groundwater-level meter was used to measure the depth to the groundwater table. An engineer's level was used to survey the elevation of the ground surface at each boring location relative to a temporary benchmark, located as shown on Figure 2, which was assigned the nominal elevation of 100 feet. These elevations, together with the depth to groundwater data, were used to compute the relative elevation of the groundwater surface in the borings. The depths to groundwater and the relative elevations are shown in Table 1. (Note: Although SJC waited a reasonable time for groundwater in the borings to reach equilibrium following drilling, the measured depth and computed elevations of the water table should not be considered to be exact. Exact measurements would require installation of permanent groundwater monitoring wells in which water is left to equilibrate for several days. However, the mean measured depth to the water table of approximately 9.93 ft. is consistent with what is known about the hydrogeological regime in the vicinity of the site. Kleinfelder staff noted a depth to the groundwater table of 13 ft., but did not state in their report how much time, if any, they waited for the groundwater to come to a steady state in their boring before they made the measurement.) sic