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Q2~p®9~~ <br /> <br />obtained. For the two shallower cuells at each site, no geophysi- <br />cal logs were obtained, and drill cuttings were usually collected <br />only near the test interval. <br />3.2.3 [dell Casing <br />After drilling and geophysical logging were completed, <br />well casings were installed. Schedule 40 PVC plastic well casing <br />was installed in the open borehole. An appropriate section of <br />slotted casing was placed at the bottom of the hole opposite the <br />test interval. Horizontal saw cuts, one to two inches long, were <br />staggered about six inches apart on two sides to form the PVC <br />slotted section. End caps were installed on the bottom of the <br />PVC slotted section. Halliburton 4-inch (10-inch outside dia- <br />meter) steel finger cement baskets ~oere installed on the PVC <br />casing at appropriate locations above the slotted sections. <br />• Individual 20 foot lengths of PVC pipe were connected with PVC <br />collars (couplings), screws, and PVC glue. <br /> <br />3.2.4 Cementing We11 Casin <br />A one-inch steel tremie pipe was installed in the <br />borehole betioeen the borehole wall and the outside of the PVC <br />well casing. This pipe was lowered to within 5 to 10 feet of <br />~' the cement basket. A cement slurry was pumped docan the annulus <br />inside the tremie pipe. The cement slurry filled a length of <br />the borehole outside the PVC casing and above the cement basket, <br />providing a seal and hydraulic isolation for the test interval <br />below the cement basket. A minimum of 50 feet of cement was <br />installed above each cement basket, except for Well GBB-3. <br />' Cement slurry volumes and weights for each well were <br />controlled to accomplish the following: <br /> <br />3-7 <br />