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than the overlying and underlying formation. <br />Cliff House Sandstone <br />The Cliff House Formation is the upper member of the Mesa Verde Group <br />in the Hesperus area and is of marine origin. It generally consists of <br />irregular to lenticular ledges of hard, fine to medium-grained calcareous <br />sandstone enclosed in softer argillaceous fine sandstone, mudstone, and <br />silty shale. <br />Like the Point Lookout sandstone, the Cliff House sandstone is reported <br />to decrease in grain size in an eastward direction. Ten to fifteen miles <br />east of the project area, the formation is composed of soft dark-gray <br />mudstone and fine sandy silt-shale with an occasional very thin lentil of <br />fine sandstone in the lower part. <br />The Cliff House sandstone has an average thickness of 350 feet <br />throughout most of the project area. It shows a slight eastward thinning, <br />probably due to the decrease in coarse clastics and the increase in <br />compactable fine sediments. <br />Lewis Shale <br />The Lewis Shale conformably overlies the Cliff House sandstone and <br />consists of dark gray to black homogeneous clay shale with scattered <br />concretions of dense argillaceous limestone and with a few thin seams of <br />bentonite in the upper part. The formation is reported to be about 1,825 <br />feet thick with the basal contact being very sharp with black flaky clay- <br />shale resting on gray mudstone or sandy shale of the Cliff House <br />sandstone. <br />STRUCTURE <br />The geologic structure of the Hesperus area is characterized by gentle <br />southward dips ranging from seven to two degrees away from the <br />structurally high La Plata Mountains to the north. It is probable that a <br />small amount of faulting is present in the vicinity of the town of <br />Hesperus. A fault with a displacement of 33 feet has been reported in <br />the Monarch mine about one mile northeast of Hesperus. While results <br />of exploration drilling conducted in the area have not revealed significant <br />faulting, it is probable that faulting is present given the relationship <br />between the structure and stratigraphic deposition. <br />/O/q/A~/N/G/O/4/tl/A/d/®/N/N/O/®/®/4/O/<l/!J/®/N/Y/(3/%!O/d/4/4/AMO/O/fY/N/G%9~9/O/N/O/.OT/i!/a9/l9/4/R% /A/9/O/Mh9/O/N/A/A/P/O/R/N/G/N/Y/K'/®/O/mil/M/O/R/®/(l/R/A <br />National King Coal, LLC King II Mine <br />Section 2.04.6 <br />Page 4 October, 2005 <br />