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Lorencim Canvcn .Mine -Groundwater Technira! Report • pipe and allowed to cure. Each borehole was drilled using a 7-7/8 inch drill bit. Coring was performed in some areas with a 5-5/8 inch drill bit drilling to the core point, and a 4-7/8 inch core barrel utilized to cut the core. During the drilling for each hole, lithologic logs were prepared by a geologist. Following the drilling to the total depth of each hole, a suite of electric logs was ran including gamma ray, caliper, micro-resistivity, resistivity, and density suites. Copies of these logs are included in the geology exhibit within this permit. During the drilling operation, any presence of water encountered was noted. • To determine the presence of alluvial aquifers, wells were installed in the alluvium of major canyons within the permit area. Four wells were installed in Lorencito Canyon, and two wells in Cow Canyon, with the other canyons having one well installed near the canyon mouth. A total of ten wells were installed. Each of these wells were installed by methods similar to those described above, except the wells did not have electric logging or coring performed. Most wells were installed with ten feet of screen and generally do not exceed thirty feet in depth. Construction diagrams and well logs are included in Appendix GW-1. Alluvial wells were assigned names based upon location. Each well was designated with an MW prefix, followed by a two or three letter code for the canyon the well was located in, and a number to designate the location with the numbers increasing up the canyon. A summary of this nomenclature for all monitoring points is included as Table GW-2. TABLE GW-2 LORENCITO CANYON MINE SUMMARY OF SITE NOMENCLATURE Abbreviation T e of Station Abbreviation Location of Station MW Monitor Well LC Lorencito Canyon WM Windmill JC Jeff Canyon P Pond LPC Little Pine Canyon SP Spring CYC Coyote Canyon None Surface Water BC Bonita Canyon PC Puertecito Canyon AC Alamosa Canyon CC Chimney Canyon CWC Cow Canyon UD Unnamed Drainage Consolidated rock wells were installed in boreholes following the logging or coring operations. Wells were installed in both the Ciruela and Primero Coals, and within the overburden, interburden, and underburden zones. In general, no aquifers (flow > 5 gpm) were noted during • drilling. Screening intervals for the wells were installed according to the lithology encountered Groundwatcr.475\Dcccmber 9, 1996 3