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panel i• aceamplished by slabbing which was selected over other pillaring methods to <br />boost productivity. Ae the pillar^ are slabbed, up to five ft. of bottom coal ie <br />• taken from the float. Two rows of pillars are left the full length of the panel to <br />provide support for the bleeder system, and era lost to recovery, ae i• the floor <br />coal beneath them. Projected panel recovery is 681 of the coal section within the <br />maximum mining height of 15 feet (equivnlant coal section of 18 feet). Production <br />panels ere separated by 300 feet barriers, which are felt necessary to assure sealing <br />of adjacent panels from the risk of spontaneous combustion. Panels are separated <br />from the mains or submains by 200 feat by 300 feet barrier pillars. <br />Production equipment includes Joy 12CM3 and 12CN12 continuous miners and Wagner <br />Teletram diaeel haulage to a Stamler feeder-breaker. Belt haulage conveys the coal <br />out of the mine to a raw coal surge stockpile at the west portal bench, where it i^ <br />loaded onto 30 ton coal haulage trucks by fzant end losdar. The trucks haul the <br />coal, which is all sold run of mina, to COV•^ rail loadout facility one mile east of <br />Paonis. <br />Evaluation of Compliance and Maximum Economic Recovery <br />The revised R2 P2 repreeent^ a significant departure from the present R2 P2, and hoe <br />serious consequences on the on the overall recovery of the coal resource on the <br />property. Raeoversbla reserves on the C-37210 lease will ba reduced from 37 million <br />tone under the existing R2P2 to about 18 million ton• under the revised R2 P2. Not <br />only is a large portion of the in-place coal resource lost due to the increase in the <br />minimum mining height (which excludes moat of the split areas), but all the coal in <br />the pod areas exceeding COV's maximum mining height will likely be rendered unminabl• <br />as a future resource. Because thi• reduction in the reeoversbl• reserve• i• almost <br />entirely related to COV's ineistenea that 3 feet of top coal be left, and that <br />(presently) a economic minimum height (entry height) of 9 feet i^ nacaesary, we have <br />focused our evaluation of compliance with NER on COV's justifications for thaw <br />parameters. <br />• Review of the individual minor modifications in our files far the Orchard Valley <br />Nina, submitted both by CWI and COV, fully supports COV contention that areas where <br />the D-seam splits, and areas where extraction is to the top of the D-seam, will be <br />subject to frequent and uncontrollable roof control problems. Instances of <br />modifications to leave top coal, to control the weak swelling mudstone roof, in thick <br />areas of the D-seam, ors noted in our files as early as August 1981, and virtually <br />every modification submitted deal^ with roof control. These roof control problems <br />repreeent a severe and ongoing safety hazard to the production crews, and also <br />present immediate quality control problems, ae the operation lacks any means of <br />removing the out-of-seam roof rock dilution, installation of a wash plant, besides <br />from being economically inteteibla in the present coal market for the minas in this <br />area, would do nothing to correct the overriding safety concerns. COV's proposal to <br />leave 3 feet of top coal, rather than some leaser thickness, i• based on actual <br />mining experience. All instances where, a• a last resort, CWI or COV obtained <br />approval for a minor modification to leave top coal, it ws• necessary to increase the <br />top coal thickness to 3 fNt to gain any consistent improvement in roof control. COV <br />hoe undertaken a detailed analysis of the depositional environment of the D-seem to <br />correlate these roof control problems to the entire reserve base, and the conclueione <br />of this study clearly support COV'e plan to target mainly the thick coal pods, and <br />leave top coal to provide a safe, economic remaining reserve base. We believe Cov <br />hoe adequately jnstiiied the need to leave top coal within the requirements of the 43 <br />CFR 3480 regulations and has met the intent of maximum econaaic recovery. <br />To support their selection of 9 feet ae a minimum average entry height, COV, ae part <br />of date including in their royalty reduction application, has submitted an analysis <br />of the effect of productivity on the overall mining coot. To reach the levels of <br />productivity necessary to achieve competitive mining costs raquiree thnt COV utilize <br />high productivity continuous miners and methods, operating in coal thick enough to <br />make use of the increased productivity. At present this thickness is 9 feet. <br />e <br />