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deeply incised valleys and drainages cutting through the perimeter of the areas to be <br />drilled. Unlike the New Horizon Mine, most of the areas to be drilled are not irrigated <br />with the exception of the eastern portion of Second Park. <br />If an aquifer is encountered, the location (depth) and thickness of the aquifer will be <br />determined from observations made during the drilling (cuttings lithology, water <br />production from the hole, and the geophysical log). As the hole is plugged prior to <br />abandonment the aquifer will be cemented off from a depth of 50 feet below the bottom <br />of the aquifer to a depth of 50 feet above the top of the aquifer, (see attached Typical <br />Abandonment Diagram for Second Park). The cement would be Portland Type II <br />cement with 6 gals of water per sack and would be pumped into the hole (positive <br />displacement) through drill pipe utilizing the drilling rig mud pump. Because of the <br />shallow nature of the proposed drilling program any aquifers that are encountered may <br />require that the entire hole be cemented from total depth to surface. In this case, an <br />aluminum cap with a hole identifier will be placed in the top of the cement to complete <br />the hole plugging procedure. If any holes fall on cultivated fields, the hole plugging <br />procedure from the New Horizon Mine (the top three feet of the hole to be filled with <br />cuttings and topsoil) will be incorporated, with hole marked with a metal fence post. <br />ITEM 5.B.6: The proposed coal exploration holes are relatively shallow and will vary <br />from about 30 feet deep to about 200 feet deep which includes the 20 feet or so that <br />each pilot hole will be drilled below the mineable coal bed. The average total depth is <br />about 96 feet. Upon reaching total depth of each of the holes, drilling mud consisting of <br />bentonite gel will be mixed to a Marsh funnel viscosity of 50 seconds. The drilling mud <br />will be pumped through the drill pipe, filling the hole from the bottom up. Drilling mud will <br />be added as the pipe is "tripped" out of the hole. The drill rig will then move off the hole <br />and onto another drill location. The hole will then be logged with geophysical tools. <br />After logging, the hole plugging will be completed by placing two bags of 3/8" bentonite <br />chips in the hole on top of the thick drilling mud. Experience in the area (New Horizon <br />Mine) suggests that the bentonite mud will recede or drop in most holes only a little (a <br />few feet to 20 or 30 feet). Any remaining open hole will be filled to a depth of 10 feet <br />with cuttings, with the objective of placing as much of the cuttings as possible back into <br />the hole. The open hole from ten feet to the surface will be filled with "sakrete." This <br />method of hole plugging is consistent with the hole plugging procedures incorporated in <br />the New Horizon Mine's Mining Permit C-81-008 issued by Colorado Division of <br />Reclamation Mining and Safety (CDRMS) with the exception that the Permit calls for the <br />top three feet of the hole to be filled with cuttings and top soil. As the primary existing <br />land use is stock grazing, (the land does not appear to ever have been cultivated) the <br />sakrete concrete plug will extend to the surface. If any holes do fall on cultivated fields <br />the hole plugging procedure from the New Horizon Mine will be incorporated. An <br />