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the anticline tends to be assymmetrical, with the more steeply dipping flank to the east side. In places, the sediments on the eastern flank are near vertical or even overturned. Exhibit C-1 is a geologic map of the McCallum Anticline and vicinity as interpreted by Kinney (1970, 1971). Subsequent glaciation and erosion have exposed the older sediments of the Upper Sandy Member of the Pierre Shale Formation along the crest of the anticline. The younger Coalmont Formation which contains the Sudduth Coal Seam is exposed along both flanks of the anticline (see Exhibit C-1). Wyoming Fuel Company's Canadian Strip Mine is located on the eastern flank of the structure near the southern nose. The proposed permit area will extend the present operation to the south around the nose of the anticline, then north along the western flank. Coal Geology. . The coal seams of the North Park area lie in the Coalmont Formation of Early Tertiary Age (probably Paleocene or Eocene). The formation is composed of approximately 4,000-6,000 feet of interbedded shales, muds tones, sandstones, and coals which unconformably overlie the Upper Sandy Member of the Pierre Shale Formation of Late Cretaceous Age. Two major coal seams or zones exist within the Coalmont Formation in the vicinity of the Canadian Strip Mine. They are in ascending order the Sudduth Seam and the Capron Seam. The Sudduth Seam is the thickest and most widely developed seam in the region and is located at the base of the Coalmont Formation resting on or near the unconformity on the Pierre Shale. The Capron Seam is stratigraphically located about 2,400 feet above the Sudduth Coal and is commonly split into two beds. From an economic standpoint, the Sudduth Coal is more commercially mineable than the Capron due to higher quality, and is the seam which is recovered at the Canadian Strip Mine. • -4-