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1 � � <br /> 1 October 1, 2004 <br /> 1 NOA Project Number: LE03-034 <br /> 3.1 Well Design <br /> 1 The anticipated monitoring well design is proposed next. The ground-water depth for the area has <br /> been reported to be between. 107 to 127 feet. The actual depth to ground water may affect the <br /> 1 proposed monitoring well design. Please see attached monitoring well design (Plate 2). <br /> Anticipated Monitoring Well Design for <br /> ' Ground Water Depth of 120 feet. <br /> Bore Hole Diameter= 6 Y2inch (hollow stem auger) <br /> 1 Anticipated Total Bore Hole Depth = 130 feet(no over drilling). <br /> Anticipated Solid Casing Below Ground Surface = 1 15feet,•from a depth o_f 0 to 115 feet. <br /> Anticipated•Solid C'asingl4bove Ground Surface =3 feet <br /> 1 Anticipated Perforated i�ell Screen Interval= 15 feet;from a depth of 195 to 130 feet. <br /> Anticipated transition seal=2 feet thick;from a depth of 111 to 113 feet. <br /> Filter Pack = 113 to 130 feet in depth (minimum 2 feet over well screen). <br /> Annular seall&rkne.rs= 2.1 inches <br /> The proposed drilling of the monitoring wells will be by a Mobile B53 truck mounted drill rig <br /> operated by Neil O. Anderson&Associates, Inc. of Lodi, CA. The rig is capable of drilling with <br /> either 6 '.h to 8 inch diameter hollow stem auger to a depth of 150 feet. Should a.larger drill rig be <br /> required should auger refusal be encountered, the drilling will be subcontracted. Sampling of the <br /> 1 soil will be either every 5 to 10 feet using a Shelby sampler through a wire line. Satisfactory <br /> conditions for�Atell completion include locating a permeable strata at or below the groundwater <br /> level. We anticipate this level to be about 120 feet plus or minus 10 feet. <br /> 1 Schedule 40 PVC, 2-in diameter casing will be installed through the hollow stem auger. The outside <br /> diameter of the Schedule 40 casing is 2.35 inches. A 2 inch annular seal will be obtainable with the <br /> 1 use of the 6 ','i inch diameter auger flight. <br /> The filter pack will be placed through the hollow stem auger. The filter pack will be surged to <br /> 1 induce settlement and checked to ensure proper filter pack dimensions. A sanitary seal will be <br /> pumped through a tremie pipe from above the transition seal to the ground surface. The sanitary <br /> seal will consist of neat cement grout with 5%bentonite. <br /> 1 Should the depth of ground water be different than 120 feet, the well design will be adjusted so 10 <br /> feet of screen are below ground water and 5 feet are above ground water where permeable material <br /> 1 exist. If no relatively permeable materials exist at the ground water surface, deeper drilling will <br /> proceed to lcw ate suitable permeable strata. Based on well logs in the area,we expect relatively <br /> permeable sands to exist near the anticipated ground water depth of 120 feet. <br /> i <br /> 1 5 <br /> 1 <br />