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1 <br />1 <br /> <br /> <br />t <br />1 <br /> <br />1 <br /> <br /> <br />1 <br />1 <br />1 <br />1 <br /> <br />1 <br /> <br />1 <br />RGI # 04548198 <br />Holnam, Inc <br />January 27, 1999 <br />Page 6 <br />air-rotary drilling method also made it difficult to prepaze accurate Gthologic logs of the wells due to the <br />intermixing of the cuttings as they moved up and out of the borehole. <br />The second monitoring well installed was the upgredient well, MW~. The first attempt to install this well <br />was in a location approximately 1000 feet north of the primary crusher. This location was in the central <br />portion of Cut 2 which had already been mined and backfilled with shaley overburden removed from other <br />cuts. Due to the unstable nature of the fill material the drillers were not able to keep the borehole open <br />to install the well casing and materials (i.e., filter pack and gout). Therefore, a second location for well <br />MW-6 was selected in an area which had not been mined. Due to the location of anorthwest-southeast <br />trending fault zone (see Figures 2 and 4, Appendix A) and the accessible azea of native undisturbed <br />geologic materials, alternative locations for MW-6 were limited. The selected location was on the north <br />side of Cut 3 near the northern boundary of the mine. The well was completed in both the Fort Hays and <br />Smoky Hills Limestone Members of the Niobrara Formation. <br />The third monitoring well installed was MW-7, a second downgadient well. Three (3) boreholes were <br />drilled before this well was successfully installed. The first two (2) boreholes were abandoned because <br />they did not encounter native bedrock material. The location of MW-7 is approximately 375 feet north <br />of the Arkansas River and approximately 500 feet east of the vehicle maintenance shop. This well was <br />completed in the Codell Sandstone. <br />The locations of the monitoring wells are depicted on Figure 4, Appendix A As-built details of the wells <br />aze included in Appendix B. A summary of well depths and construction details is presented in Table 1. <br />Well development was performed by Layne between August 27-29, 1998. Development of the monitoring <br />wells was accomplished by swabbing and bailing. The screened interval in each of the wells was swabbed <br />with aught-fitting surge block. Each of the wells was then bailed until all of the water was removed from <br />the well. Wells MW-5 and MW~ each took several days to recover after bailing. Therefore, fresh water <br /> <br />