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r photographs. At this time, it was found that the area under the former Yey Loci: pumps had leen excavated to the size shown on Figures 7, S, and 9 . The spoil had been piled along side of the second excavation on the preexisting asphalt surface (See photograph, Fig. 7) . When contacted by Richard Thorpe, the sport of Stockton stated that the ex- cavation had been necessary to repair the broken water line that serviced port tenants . At this time, this brings up-to-date, field activitie:: at the site. AREF GEOLOGY AND HYAROGEOLOGY The project lies in an area that is classified in Reference 1 as a flood basin of the S,an Joaquin River, having shallow deposits of Recent to FleJ.atocene Age. The deposits are typically low permeability materials such as clay, silt, bottom muds and perhaps organic materials. Sands and gravels are found but their percentage content of the vertical section is low. 1n the upper 50 feet of deposits, sands and gravels might vary from 0 tc 20 �. The excavation shown in the photographs in figure 4 show the near surface deposits to be approximately flit-lying. The uppermost foot appears to be fill material with about one more foot of yellow silt that also might be fill . These materials overly a thin layer of dark, carbonaceous, clayey silt that obviously represents a recent stagnant area bottom. The materials from the dark layer to pit bottom, about 12 feet below ground level , are fine silt and sand with a yellowish tinge;. Some layers of pebbles and coarser material are interfingered in the silty material . 1 The pit materials were. mo'st when excavated according tc Richard Thorpe, however they have now dried and are Lard but friable. Slumping has occurred on all sides and several feet of slump material now covers most of the bottom. Peripheral cracks are appearing around the excavation and more slumping will likely occur; although perhaps not in the dry season. The pit bottom is approximately a' groundwater level . It was dry at both times that the writer visited it; however, Richard Thorpe states that watez, entered the pit at night immediately after excavating blit later drained out. Figure 1 shows the area to be about 5 feet above MSL. Figure 3. contours on groundwater elevation prepared by Sar. Joauin County in 1989, shows the area groundwater tc be at about _ -10 feet MSL. Although these da"a are not crood in this area of the map owing to a lack of data, it appears that the seepage seer. by Richard T:corpe was groundwater. Reference gyro. i show= the site :c ;verly degraded aqu rs;s that had a chloride ccatent of ever 300 ppm aE far back as ' a