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i, Well Drilling Operations Monitor Well # 3 ii This was the first monitor well location to be bored and completed. The rig was on site at 93 AM, April 4, 1991 . The well was bored to about -201GL, with cuttings described continuously. A log of each boring is shown on its respective casing and completion diagram (Fig. 2 for k MW # 3) and. on Figure # 5 . The soils on ' each diagram have been classified by observers judgement using the Unified Soils Classification System. A chart illustrating this system is appended. Briefly, about 3 ' of fine micaceous silt was found near the surface, silty sands from -3 ' to -7 1/21 , clayey sand from -7 1/2 ' to -81 , various mixtures of silty, medium to coarse grained sands from'i -8 ' to -151 , and coarse sand and gravely sand from -15 ' to x' 201 ; the total depth. Groundwater located at about -8 ' by:, the driller. I No soil sample was taken at the surface'} owing to the wells location, about 200 ' southwesterly 'of the former tank site. The core spoon was run at -5 ' and again at -b ' , but owing to the very loose nature of the silty sands, insufficient ' recovery was obtained for sampling in either attempt. Some loose sand was found in one brass _ube, ,; no odor or visible contamination was present. When water was encountered at about -81GL, a core was immediatelylitaken (at -101 ) . Only i. one, three inch sample was recovered. A. second attempt was made, also with no recovery. The 31' sample noted above was the only sample from MW # 3 ... it t The casing was designed to go to bottom at -201 , with perfs . extending to above the water table .l: The casing would not go to bottom and was worked for about i45 minutes before stopping at -19 1/21 , about 11 ' into the water table . The well was gravel packed across the perforated interval and to one foot above (constant measurements taken by driller) . The well was then swabbed for about 30 minutes to develop and clean the well bore. A hard rubber disk on a rod k was used as a swabbing tool . During.; swabbing the casing pulled up about 1 1/21 , bottom now at -181 , and could not be i forced deeper. The top of the casing was cut to accommodate ` the new depth. Owing to the shallow. depth of the well and the shallow water table, adjustments had to be made to the casing plan. These adjustments were'� approved by Harlan { Knoll , EHD, who wa's at the well site . The final well completion is as shown on Figure 2 .11, The casing string consists of 4" ID-flush, screw joint, schedule 40 PVC . From bottom up, blank, slip-on bottom cap, .02" horizontal perforations from -18 ' to -5 ' (WT at -8,' ) , blank casing from -5 ' to surface . The perforated inte'xval: was repacked with additional gravel to bring the top 'above the perforations . , i� 4