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from the north and west and that the hole 310136-2 is closer to the recharge area than are holes <br />located further up dip. The mine continues to be relatively dry. The amount of water seeping into the <br />mine did not increase as the result of mining deeper. The East Mains were driven to within about 2700 <br />feet of the axis of the Red Wash syncline. Conditions at this point were dry. Observations <br />underground show fractures and joints to be non-existent. Fractures and joints, if present, would <br />provide higher permeability in othervvise tight strata. Jointing as observed at surface does not appear <br />at depth, suggesting the jointing is controlled by depth and is the result of lithostatic unloading. <br />Development of the B Seam to date has experienced minor seeps from both roof and ribs that typically <br />dry up in ten (10) days or so. To date (1/99) the floor has been dry. <br />II.B.6 Coal Reserves and Quality Coal reserves for the Deserado Mine have been estimated <br />for four (4) categories of reserves: coal reserve base; mineable reserve base; recoverable raw coal <br />reserves; and recoverable clean coal. Reporting four (4) categories of reserves is a change from past <br />practices but is necessary so that all reserve estimates are consistent with those required by federal <br />regulatory agencies. Table II.B-1 is a summary of the reserve estimates by category and by lease for <br />the B and D Seams. The Deserado Mine reserves are calculated using a coal density factor of 84.24 <br />Ibs/ft' or 1834.7 tons/acre-foot. The categories of reserve estimates are defined and the calculation <br />methods explained in the following. The fire in the tailgate of longwall panel 9 resulted in sealing off <br />a significant portion of the remaining reserves in the D-Seam. The reserve estimates reflect the <br />changes in the mine plan as a result of the fire. <br />II.B.Ii.a Coal Reserve Base is a category of reserves which defines the total coal in-place using the <br />following criteria: <br />• minimum seam thickness of 28 inches to an elevation 500 feet below the lowest <br />elevation on the Deserado Mine Logical Mining Unit <br />• minimum seam thickness of 48 inches from a depth of 500 feet to 3000 feet below the <br />lowest elevation on the Deserado Mine Logical Mining Unit. <br />Boundaries used for estimating the "coal reserve base" includes the Federal coal lease boundaries <br />and the individual seam outcrop. In addition, the lease stipulations for Federal coal lease C-0126669 <br />prohibit the mining of coal within 100 feet of the 100 year flood plain of the White River. Therefore, <br />this area is also excluded from the "coal reserve base". Relative to the D Seam, the area of the <br />abandoned Staley-Gordon mine is also excluded from the "coal reserve base". <br />Partings were included as coal thickness if the ratio of coal to parting was greater than 3:1. If the ratio <br />of coal to parting was less than 3:1 then each individual split would have to meet the minimum <br />thickness criteria to be included as "coal reserve base". Thickness data from each of the drill holes <br />for each seam were then plotted on individual seam maps and then isopach maps constructed based <br />on the thickness values. Reserves were estimated by planimetering areas of different thickness which <br />(Permit Renewal #3 1/99) II.B-9 <br />