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Because of required drilling depths, EFCI does not generally drill pilot <br />holes to identify coring intervals. Rather, coring begins above the <br />target interval based upon available geologic information. Coring is <br />utilized primarily to quantify coal depth, thickness, and quality, and <br />parting thickness, and location. Core samples are recovered, logged, and <br />sent to a laboratory for analysis. <br />In most cases, exploration drillholes are logged using conventional <br />electric logging methods to obtain additional information. Where the need <br />exists for additional groundwater monitoring information, drillholes may <br />also be completed as monitoring wells. <br />During drilling, EFCI will control dust from drilling and related <br />activities, divert and control both natural runoff from disturbed areas <br />and fluid loss from drillings, and will clean-up any trash or debris. If <br />air is utilized as the circulation medium, dust from drilling will be <br />controlled by a flexible shroud at the drill collar. Drill cuttings and <br />• drilling fluids will be effectively contained by mud pits within the drill <br />pad area. <br />Site Reclamation <br />Upon completion of drilling and related activities, any driilhole not <br />completed as a monitoring well will be backfilled, sealed and abandoned. <br />During drilling, fluid return will be monitored to identify the depth and <br />extent of any water producing zones. Upon abandonment, a cement grout <br />seal will be established, extending 20 feet above and below any such <br />zones. The remainder of the drillhole will be backfilled with drilling <br />mud and/or cuttings to within 20 feet of the surface. A cement plug will <br />be established from the top of the backfill to within three (3) feet of <br />the surface, a metal post will be placed in the hole as a permanent <br />marker, and the remaining interval will be backfilled with soil material <br />to the ground surface. <br />All trash and debris will be removed from the drill site for disposal. <br />Where drill pads are necessary, mud pits will be allowed to dry out and <br />will be backfilled with drill cuttings and/or previously excavated <br />material. Any excess cuttings will be spread over the site, and <br />2.02-5 <br />