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Vile. I Hunter & Ass cc i a I es informally visited I h C site during the ratter part of 1999 and after accept i nv, the i ob of Prepar i rip, this repot , re-visited the site on i Mi r ch 1 4 , 1990. The photos used in Figs . 6 and 7 were taken at that tIFTIC. AREA GEOfAXW AND HYDRC0G.EOLCK;)' The project I i es in an area that is classified in Reference I as a flood basin of the San 3oaquin River , having, shallow deposits of Recent to Pleistocene Age, of flood basin, low perr-ricab i I i I y, clay , silt , sand, gravel and s ome I i me s organic materials. .Sand content in the area is estimated to vary f rorn 0 feet to 10 feet in the Lipper 50 feet 0 1 material (0 to 20 `N). The preparers of this report did not witness either excavation and have seen oil I v the material remaining; The , i n the spoil i I 'DilC seen on Figure 7. materials here, disturbed arid mixed by the excavating process, appeared io be yellow colored, silty sand. The materials excava led were described by Richard Thorpe, who supervised all site operations , as tan colored silly 5and. No clays and organic maier ial s ".were found. The tipper 2 feet or so were probably sand), fill material covered by asp!ial t . No groundwater was encountered during excavating it 12 feet in Excavation # 1 ; however , some water entered the hole at night and disappeared (Wring the day, indicating some sort of t i da I effect . Earth tides can be seen in some sha I low water art-as even when actual ocean Tides are not involved. I n a n y event , p,round-water appears to be found at just below 12 feet, surface refer- ence. Inasmuch as the port deepwater channel is only about 150 feet north o I t 11 e first excavation and the M51- elevation is only about plus 10 f eC t , water should have been e,icountered, Average g r 0 U n dk"'a I_.r depth as es I ima ted by the San Joaquin County Flood Con r r o I District is shown on Fif.Ure 5 , The 1989 groundwater eleVaTj011 shown for the project site is either outside or at the very perimeter of map data. Mr . Fregriaro, Port of Stockton, reported that to his knov,1lCdVe there are no water wells within perhaps a cne mile radius of the site. All water used in the Port is piped- in nmnicifat water . Referencethe site to overly degraded aquifers which had a chloride content of over 300 ppm as far back as, 1963. The current pumping depression of -40 feet shown northerly of the project site likely has drawn and will draw degraded water in that direction- The entire port is in a naturally tov,, area that either had 10 be filled or regraded during port construction. 5 z