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I • 2.04.6 -GEOLOGY DESCRIPTION <br />REGIONAL GEOLOGY <br />The following description is excerpted from the NEDO Project Geological <br />Report, contained in relevant part in Appendix 4. Additional detailed <br />information regarding regional and project site geology is contained in <br />that report. <br />The King Coal Mine (and the proposed King II Mine) lies at the northwest <br />edge of the San Juan Basin, covering approximately 26,000 square miles <br />of northwestern New Mexico and southwestern Colorado. The <br />sedimentary strata of the basin were deposited at the western margin of <br />avast epeirogenic sea occupying the central area of the North American <br />continent during the late Cretaceous Epoch. Extensive deposition of coal <br />forming materials occurred during a succession of <br />regressive/transgressive migrations of the shoreline in northeast <br />(seaward)/southwest (landward) direction. With each successive cycle <br />the maximum transgressive cycle shifted to the northeast until the final <br />disappearance of the sea. The ultimate result was a jagged wedge of <br />non-marine sediments in the southwestern area of the basin, <br />intermingling with marine strata to the northeast. With each <br />transgressive cycle accumulated the transitional strata of barrier beach, <br />• marginal shore swamps (coal bearing), paludal (coal bearing), and other <br />lower coastal plain deposits. <br />LOCAL GEOLOGY <br />The local area is characterized by southerly to southeasterly dipping; <br />sedimentary rocks of late Cretaceous age which has been deeply eroded <br />to the north. <br />The uppermost formation exposed locally is the Cliff House Formation, <br />which is the upper member of the Mesa Verde Group. It is of marine <br />origin and is composed of irregular to lenticular ledges of hard, fine to <br />medium grained, calcareous sandstone in softer argillaceous fine <br />sandstone, mudstone and silty shale. The top of this formation has been <br />removed by erosion, leaving an average thickness of 350 feet. The Cliff <br />House Formation overlies the Menefee Formation. <br />The Menefee Formation, which is the middle member of the Mesa Verde <br />Group, is composed of a complex assemblage of cross-bedded <br />sandstones, black shales and coal beds. Up to seven coal seams have <br />been identified by the U. S. Geological Survey. The Menefee Formation <br />has an average local thickness of 300 feet. The Menefee overlies the <br />Point Lookout Formation. <br />ui m+imioi0anvimdinimmmis~moimioa~mnaoninanoimrnmoiomiaiA.oia~~sioiroimisroicm~aiviommnui<v.+~~o~miamycoimmmiviamiiuioievoi.-i, <br />National King Coal, LLC King II Mine <br />Section 2.04.6 <br />Page 1 October, 2005 <br />