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<br />3.3 Coal Geology <br />The cazbonaceous zone containing the coal beds of interest occupies the basal 200 to 300 feet of the <br />Lower Williams Fork Formation of the Mesaverde Group. Within this interval, Western Fuels has <br />identified seven ('~ apparently distinct coal seams. In ascending order, these seams are: <br />• B Seam <br />' • D Seam <br />• E Seam <br />' • F Seam <br />• G Seam <br />• H Seam <br />t • ]Seam <br />' In addition to the seven (7) seams listed above, Westem Fuels has also identified a thin somewhat <br />continuous coal located immediately below the B Horizon in the Iles Formation. This coal, referred to <br />as Iles Seam, has been included in the reserve estimates. Plate 3 is an Index map showing the location <br />of cross sections. Plates 4, 5 and 6 show seven typical stratigraphic cross sections, (structure is shown <br />below each section) and illustrates the stratigraphic relationship of the seven seams in the Lower <br />Williams Fork plus the Iles Seam. Four (4) typical geophysical logs are included as Plate 13 for <br />illustration. Only the B and D Seams are of sufficient thickness and areal extent to be considered <br />economically recoverable. The other five seams which overlie the B and D Seams are thinner and less <br />' continuous and aze not mineable. These upper five seams are difficult to correlate over large azeas <br />within the Deserado Mine area. The seven seams located in the Lower Williams Fork aze briefly <br />' described in the following: <br />3.3.1 $_St:aai The B Seam is the thickest and most laterally persistent coal seam in the Deserado <br />' Mine area. This seam vazies from less than four feet thick to over twenty feet thick. Although this is <br />the thickest seam in the azea and underlies the entire Deserado Mine area it is also the most geologically <br />complex of the seven seams. Seam complexity is the result of partings and major seam splits which <br />tend to divide the seam into two major parts which are identified as: lower and upper B seam. <br />Previously, (MLR Permit Section II.B), the lower, upper B Seam, and upper B Seam split were refeaed <br />to as the A Seam, B Seam and C Seam respectively; where the B Seam is not split, the Seam was <br />previously referred to as the A/B/C Complex. Plates 4, 5 and 6 show the stratigraphic relationship of <br />' the B Seam and splits to the underlying B Horizon sandstone, the Iles Seam, and the other six seams <br />located stratigraphically above the B Seam. Exploration drilling by Westem Fuels has defined major <br />splits in the B Seam. These splits render coal in the B Seam unrecoverable in portions of the Deserado <br />12 <br /> <br />