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Geophysical Logging: On completion of drilling and core recovery, geophysical logging will <br />be completed for each drillhole to obtain additional geologic information. A truck-mounted <br />geophysical logging unit will be used to obtain, correlate, and store logging information. <br />This information may include density, gamma, caliper, neutron, focused electric, sonic, <br />verticality, temperature, and conductivity. CCR will retain in its files all drill and geophysical <br />logs for at least one year, and will make them available for inspection by CDRMS <br />representatives. <br />Encountered Aquifers: There are no aquifers in the zone where drilling will occur. Baseline <br />studies conducted previously for the Lorencito Mine (Permit C-96-084) cover the <br />exploration project area. Further, annual hydrology mining has been conducted and <br />reported to CDRMS. The studies and the monitoring indicate no aquifers, save for very <br />localized conditions that produce very little water, are present in the exploration drilling <br />zone. The strata and coal in the drilling zone outcrop in numerous areas of the project area. <br />There are few springs in these areas, and those that are present produce very little water thus <br />supporting the findings during baseline and monitoring studies. See the hydrology <br />discussion above in Description of the Lands to be Affected. <br />Drill Hole or Well Plugging - Sealing and Abandonment: All drillholes will be plugged, <br />sealed, and abandoned. None are to be converted into a groundwater monitoring or water <br />well. Deeper drillholes will be plugged with a minimum of 6 cubic yards (about 750 feet) of <br />cement slurry - this is the off-road transport capacity of a cement truck. Shallower drillholes <br />will be plugged with between 3 and 5 cubic yards of cement slurry (as appropriate). The <br />cement slurry will be tremied into the drillhole from the bottom of the hole, up through the <br />target units. This will effectively plug and seal all coal beds and potential groundwater <br />aquifers to prevent vertical groundwater migration and cross-contamination of aquifers. <br />The drillhole interval will also be filled with any drill cuttings and the drillhole will be sealed <br />with a surface plug of cement within one to two feet of the surface. The CBM well pads are <br />periodically graded and limiting the plug to within two feet of the surface will allow <br />unhindered grading operations. Reclaimed drillhole locations will be marked with a metal <br />survey cap below ground level at the top of the cement plug. All drillhole locations will be <br />accurately surveyed, and distinctly numbered, allowing for future identification. <br />Abandonment reports will be prepared and filed, as required by applicable regulations. <br />Exploration Site Reclamation: Following completion of exploration activities (drilling, <br />sampling, and geophysical logging) for each exploration site, drillholes will be plugged, sealed <br />and abandoned, as previously described, and exploration disturbances will be reclaimed. In <br />accordance with Rules 2.02.2(2)(0 and 4.21.4(4), excavations, artificial flat areas, and <br />embankments created during exploration will be returned to their original contour promptly