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• The slotted 2 inch casing extends from 25 to 45 feet bgs Blank 2 inch casing extends from 25 I feet to the surface Number 3 sand was placed opposite the slotted casing and 6 feet above the slotted casing A hydrated bentonite transitional seal was placed between 16 and 20 feet and from 16 feet to the surface the annulus was filled with hydrated cement A steel traffic box was I placed over the well This well was then developed by removing about 50 gallons of water At that time the pumped water was free of silt and sand and most of the clay The well casing was surveyed to sea level through the Stockton City BM-29 The soil samples takeri at 15, 25, 35 and 45 feet bgs were found to be free of hydrocarbon contamination All the drill cuttings were placed in steel drums and are being removed to a landfill within a few weeks See Bonng Logs and Cross-section Figure 1 ' GEOLOGY The site and all nearby terrain are underlain by non-marine fine grained sediments which are tentatively assigned to the Modesto Formation of Pleistocene age ( USGS Bulletin 1470 I Marchand and Awordt, 1981) Although the Modesto is typically composed of coarser-grained material such as sands and gravels it is reasonable on the basis of stratigraphic position, to consider these finer-grained sediments to be a distal portion of the large alluvial fans, which make ' up the Modesto The materials penetrated in this site bonngs are chiefly clay, silty clay and clayey silt Sandy strata are present in the bonngs between 25 and 30 feet and below 50 feet bgs interbedded with silts and silty clay Bedding is absent or non-distinct but appears to be � . essentially horizontal The soil unit found in most of the bonngs at 60 feet is a clay or a silty clay It is a silty clay in the area around the former tank pit and becomes a pure clay at wells BM-8 and BM-7 A silty clay is more permeable than pure clay In 1993 we measured the Hydraulic Conductivity and found it to be 15 feet per day At that time the water table was 50 feet below the surface and the water was flowing in a silty sand Yours truly, CU,c..�c�cF John Cussen RG #6506 I Enclosures 1 Figure CFCAU 3 Boring Logs I 3 Laboratory Reports Distnbution Mr Roger Liston, Darpetro, Inc Ms Carol Oz, San Joaquin County EDH 5 I