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Litholoev <br />Kirtland shale. The Kirtland shale is composed predominantly of gray shales that contain <br />thin layers of interbedded siltstone and sandstone. This shale member contains little coal <br />or carbonaceous shale due to the lack of accumulation of organic material at the time of its <br />deposition. <br />Fruitland Formation. The Fruitland Formation is generally composed of interbedded <br />sandstone, siltstone, shale, carbonaceous sandstone and siltstone and coal. The coal beds <br />are generally the most continuous rock units in the Fruitland Formation. Structurally, the <br />mine area is uncomplicated. Units within the Fruitland Formation dip 6° to 8° to the <br />southwest and strike N60°W. Structural contour maps constructed from drill hole data for <br />the tops of each seam indicate that no major faulting or folding has occurred within the area <br />to be affected over the life of the project. The three major seams of economic importance <br />are A, B and C Seams. <br />A generalized stratigraphic column with seam and inner burden thickness ranges has been <br />included as Figure 3. Electric logs (natural gamma, density, resistivity and self potential) <br />were run in most of the drill holes. Several rider seams are also found 20 to 30 feet below <br />the surface. These rider seams border the Kirtland shale described above and are relatively <br />thin by nature, thereby making them irrecoverable and uneconomical from a mining <br />standpoint. Thirty to fifty feet below the lowermost rider seam is the A Seam. The A Seam <br />is generally 4 to 5 feet thick with intermittent shale partings. <br />The B Seam is found 6 to 12 feet below the A Seam. This seam is the thickest, generally <br />averaging about 11 feet. Thin partings of shale are found in the B Seam; however, they are <br />consistent in thickness or occurrence. The C Seam is 20 to 30 feet below the B Seam and <br />is approximately 9 feet thick. The erratic shale partings descnbed above are more persistent <br />in the C Seam, although the composition of the partings (shale) is about the same as those <br />in the other seams. <br />Pictured Cliffs sandstone. This formation is composed of white to yellowish-gray massive <br />sandstone. It can range up to 200 to 250 feet in thickness. It also includes sandstones and <br />shales beneath the massive sandstone layer. This formation is considered bedrock at the <br />Chimney Rock Mine Site. No mining or other disturbance will take place below the point <br />of contact between the lowermost seam (C Seam) to be mined in the Fruitland and the <br />Pictured Cliffs sandstone. <br />Coal Quality <br />The coal seams located within the area to be affected over the life of the operation are <br />projected to be medium volatile bituminous in nature. The A and B Seams contain several <br />thin shale partings while the C Seam contains small erratic shale partings. The three seams <br />exlu'bit excellent coking characteristics and can be considered a premium metallurgical <br />2.04-7 <br />