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Drilline Onerations - Up to three rotary drill-rigs, capable of rotary drilling and spot-coring, will be utilized <br />for general exploration work. The drill-rigs will be truck-mounted, rubber-tired units, capable of operating in <br />rough terrain. Support equipment for each drill-rig will include but not be limited to a water truck, pipe truck <br />and/or pipe trailer, rig-up truck, air compressor, core trailer, and two or three 4 x 4 pickups for drill-crews and <br />company representatives. For each dri]lhole, a short section (typically 40-60 feet) of threaded surface casing <br />will be set to stabilize unconsolidated surface materials. Drillholes will be a nominal 6.25 inches in diameter <br />and will vary in depth from 330 to 2,000 feet. The location and anticipated total depth for each drillhole are <br />identified in Table 1. It is anticipated that the Wadge and Wolf Creek coal seams and associated roof and <br />floor units will be cored in each drillhole. If other coal seams of interest are penetrated they maybe cored, as <br />well. Cores will be recovered, examined and logged by a qualified geologist, and core samples may be sent- <br />off for analysis of coal and roof/floor chemistry and characteristics and rock-strength parameters. It is <br />anticipated that the majority of drillholes will extend approximately 30 feet below the Wolf Creek Coal Seam, <br />but none will extend into the Trout Creek Sandstone. The primary circulation medium will be water and <br />drilling mud. In the event that subsurface conditions are favorable, air or an air/foam medium may be utilized, <br />as an alternative to mud. Water for drilling will be obtained from stockponds located on fee surface controlled <br />by Peabody Investments Corporation JCC will specify in any drilling contract .that only non-toxic, bio- <br />degradable compounds and additives maybe used for drilling. <br />Geophysical Loeeine - On completion of drilling and core recovery, geophysical logging will be completed <br />for each drillhole to obtain additional geologic information. Atruck-mounted geophysical logging unit will be <br />used to obtain, correlate, and store logging information which may include density, gamma, caliper, neutron, <br />focused electric, sonic, verticality, temperature, and conductivity. JCC will retain in its files al] drill and <br />geophysical logs for at least one year, and will make them available for inspection by an authorized officer. <br />Phased Geotechnical Investi atg ions -The proposed phased geotechnical investigations will involve drilling <br />(hollow-stem auger and core) and sampling, backhoe trenching, physical testing (ie: cone penetrometer, etc.) <br />and geophysical methods. In general, the access, drill pad construction, and drilling considerations and <br />operations will be similaz to those previously described, except that a smaller drill-rig may be utilized and a <br />hollow-stem auger may be utilized to drill and sample unconsolidated su~cial and shallow weathered <br />materials. In conjunction with drilling operations, physical testing (cone penetrometer) and geophysical <br />methods may be utilized. As a compliment to drilling and sampling operations, a small rubber-tired or Vacked <br />backhoe may be utilized to characterize surficial materials through shallow (maximum of 10-foot depth) <br />trenching and sampling. Prior to trenching, available topsoil will be recovered and windrowed adjacent to the <br />trench location. The trench will then be excavated and associated characterization and sampling completed <br />prior to backfilling the trench. Appropriate safety precautions for confined space entry will be observed, <br />dependent on the depth and configuration of the trench excavation. <br />Exnloration Maintenance Activities -Other than initial road maintenance to establish good access, it is <br />anticipated that access road maintenance requirements will be minimal, since the majority of the exploration <br />efforts will occur during the dry summer months, or when the ground is frozen. Other maintenance <br />requirements will include general housekeeping in active exploration azeas and regular inspection and <br />maintenance (as necessary) of drainage structures. <br />Monitorine or Water-Sunuly Well Comnletion -Dependent on location, depth, and groundwater conditions <br />encountered, selected exploration drillholes may be converted to hydrologic monitoring or water-supply wells. <br />In compliance with applicable provisions of 43CFR 3484.1(a), prior to conversion of an exploration drillhole <br />to a monitor well, authorization will be obtained from the jurisdictional regulatory authotity(s). Given typical <br />timing for exploration activities, if JCC determines that it would be beneficial to convert an exploration <br />drillhole to a monitoring or water-supply well, both the BLM and CDMG will be immediately contacted and <br />provided with relevant drilling information and a justification for the well. JCC would then obtain preliminary <br />concurrence prior to proceeding with well completion. Wells completion would involve casing the open <br />drillhole, placing 20-slot screen and 8/12 silica sand or apre-packed, stainless steel or PVC well screen in the <br />G:\Environmental\EXPLORATION WORK\EXPLR 2006 BIG ELK\Big Elk 2006 NOI App. Fortn.doc Page 12 of l7 <br />