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air/foam medium may be utilized, as an alternative to mud. Water for drilling will be obtained from stock ponds located on surface controlled by CCR. Drilling contracts will specify that only non- toxic, bio-degradable compounds and additives may be used for drilling. Geonhysical Logging On completion of drilling and core recovery, geophysical logging will be completed for each drill hole to obtain additional geologic information. Atruck-mounted geophysical logging unit will be used to obtain, correlate, and store logging information which may include density, gamma, caliper, neutron, focused electric, sonic, verticality, temperature, and conductivity. CCR will retain in its files all drill and geophysical logs for at least one year, and will make them available for inspection by an authorized Division representative. Exploration Maintenance Activities -Other than initial road maintenance to establish good access, it is anticipated that access road maintenance requirements will be minimal, since the majority of the exploration efforts will occur during the dry summer months. Other maintenance requirements will include general housekeeping in active exploration areas and regular inspection and maintenance {as necessary) of drainage structures. Monitorine or Water-St~pl~Well Completion -Dependent on location, depth, and groundwater conditions encountered, selected exploration drill holes may be converted to hydrologic monitoring wells. In compliance with applicable provisions of 43CFR 3484.1(a), prior to conversion of an exploration drillhole to a monitor well, authorization wilt be obtained from the appropriate regulatory authority(s). Wells completion would involve casing the open drill hole, placing 20-slot screen and 8/12 silica sand or apre-packed, stainless steel or PVC well screen in the desired completion interval, establishing bentonitic plugs above and below the screened interval and grouting the well annulus to prohibit vertical migration and cross-contamination of aquifers, and developing the well by successively flushing and pumping the well bore. Figure 2, Typical Monitoring Well Completion, illustrates typical completion methods. [f an exploration drillhole is converted to a monitoring well, a detailed well completion report and diagram will be forwarded to the appropriate regulatory agencies. Once the well is no longer needed, it will be plugged and sealed in accordance with appropriate regulations. Proaosed Reclamation Methods: The proposed exploration program is designed to minimize new surface disturbance by utilizing existing roads and trails to the extent possible, placing drill pads adjacent to existing roads, utilizing previously disturbed areas for drill pads, and limiting pad size. Surface disturbance, and reclamation requirements and costs are summarized by Table 2. The following sections describe the specific proposed reclamation practices to be used to return exploration disturbance to a stable condition and productive use. Drill Hole or Well Pluggine - Seali~ and Abandonment: All drillholes will be plugged, sealed, and abandoned unless they are converted for long-term use as a monitoring well. Deeper drillholes will be plugged with a minimum of 6 cubic yards (about 750 feet) of cement slurry -this is the off-road transport capacity of a cement truck. Shallower drillholes will be plugged with between 3 and 5 cubic yards of cement slurry (as appropriate). The cement slurry will be tremied into the drillhole from the bottom of the hole, up through the target units. This will effectively plug and seal all coal beds and potential groundwater aquifers to prevent vertical groundwater migration and cross- contamination of aquifers. Any remaining open drillhole interval will be filled with other suitable plugging material (plug gel or vendor-specific grout compounds) and/or drill cuttings to within 5 feet of the ground surface and the drillhole will be sealed with a surface plug consisting of at least 5 feet of cement. Information on nn~~ n..up rp,eo Nai ivm