Laserfiche WebLink
s <br /> =s - _-mac - <br /> ,� wq gpg�7- <br /> .101111 <br /> s <br /> �y <br /> 34 and situated perpendicular to the western wall of Building 34. A two-inch-dii-meter <br /> slurry filled pipe stub in the Building 34 foundation exists about S inches above the <br /> ground surface. This pipe stub may have stemmed from the diene! tank. <br /> 2.3 PREVIOUS INVESTIGATIONS <br /> Mr. David Koll was present during removal of the gasoline tank and reports that the <br /> sol!surroundingthe 50-0-gallonThirty-six <br /> r Yaa�llne cubicnk was yards of t soil was contaminated; <br /> rhowever, <br /> e novedalong with the <br /> samples were analyzed. <br /> gasoline tank in 1985. <br /> No previous investigation has taken plar!, at the 500-gallon diesel tank location. <br /> 2.4 ENVIRONMENTAL SETTING <br /> 2,4,1 REGIONAL GEOLOGY <br /> Plant 33 is located just east of the Sacramento-San Joaquin delta, near the margin of <br /> the Creat Central Valley of Califr ta. The valley is l. s It, sane, and gravel.sedime300sfeet of of <br /> a series of nearly flat lying beds ocv <br /> sediments in the vicinity of the site include Recent Alluvium, the Pleistocene Victor <br /> Formation, and the Plio-Pleistocene Tulare Formation. These units are laterally and <br /> vertically heterogeneous, and it is difficult to distinguish between them in the subsurface <br /> 7 <br /> (California Department of Water Resources (CDWR) ). <br /> r Both the Recent Alluvium and the Victor f=ormation consist of discontinuous beds of <br /> sand, gravel, clay, and silt, deposited in a continental alluvial fan environment. Sand <br /> and gravel dominate in fan areas,while clay and silt are the dominant interfhn deposits. <br /> As the lithologies of the recent Alluvium and Victor Formation are similar, these two <br /> units are not distinguishable on driller's or <br /> rrtgeophysical(CDWRheir combined thickness <br /> 1967). <br /> in the site area is probably between 100 a <br /> The Tulare Formation is the major source of groundwater in the Stockton area. It <br /> consists of semiconsolidated, poorly sorted,discontinuous deposits of sand, gravel, clay, <br /> and silt. A regionally extensivewest of he, the <br /> Joaquin Corcoran Clay,occurs near the top of <br /> the Tulare Formation to areas <br /> 2.4.2 LOCAL GEOLOGY <br /> rans adjacent to the site, the upper 60 feet+ <br /> Based on logs of borings drilled by Cal T4-A <br /> soils below the site consist predoriinantly of clayey silt. Thin fine sandy interbeds occur <br /> sporadically: Groundwater--was.-not....encountered_at_depths of 60 feet in November -._..... . ....... _._......... <br /> 1988. <br /> 26 <br /> SF0316051wp'\00231 <br />