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Catnv Begej - 2 - October 24, 1989 Two known faults exist in the tdarr Strip Mine area. These faults are nearly perpendicular to the axis of the Johnny Moore Buntline. Tneir movements are pelieved to be normal, and displacements range from 100 to 150 feet. Williams and Bush Draws appear to be surface expressions of these faults. The oldest formation exposed in the mine plan area is composed of the Pierre Shales. These rocks are mostly marine in origin and are approximately 4500 feet in thickness. They are predominately dark, usually olive, brownish or dark gray. Occasional lighter colored shale and sandstone beds are interbedded in this formation. The Coalmont Formation rests unconformably on the Pierre and is the only coal bearing formation in North Park. This formation is about 5000 feet thick and is estimated to be Mid-Tertiary in age. It is divided into two distinct but unnamed members. The upper 1500 feet consists of light interbedded sandstones with occasional conglomerate beds. The base member is a massive sandstone about 50 feet thick. The 50 foot thick Sudduth Coal Seam rests on this sandstone. Lying unconformably above the Coalmont is a structure composed of shales, volcanic ash, tuffs and conglomerates of the North Park Formation. The Quaternary Alluvium rests unconformably upon the North Park and consists of sand, gravel, clay, dune sand and glacial till. Three aquifers are found in the mine plan area. They include perched terraces, stream laid alluvium and the Sudduth Coal seam. Trans missivities are low for the coal seam while the other aquifers tend to be limited in volume and appear to be discontinuous. The Sudduth, Williams, Bush and ~ r~~~ Bolton draws are typed as intermittent streams. ~~~~" _~ _; ~l Drill holes 77-12, 77-14, 79-4, 80-23c, 80-28c, and 80-29c show S.A.R's /,1 - ~ above 10. While most of these holes only show parts of the total depth to ~ ~ ~ -J i have nigh S_.A.R.'s, Drill hole 79-4 shows over 400 feet of S.A.R.'s in excess of 13.700. Kerr Coal has stated in this revised permit application that these high readings are misleading. They felt that the samples were contaminated by the drilling fluids used. Without much solid information they have discounted the significance of these assays. They claim that any high S.A.R.'s will be corrected during backfiiling b.v the normal mixing of overburden b.v the equipment. ."7 ~~-- Projected swell factors of 244 are claimed by the Company to be confirmed by "„ y~'' ' aerial measurements of Pit 720 and its adjoining spoil oil e. Table 63 ~.",-'` ~,.w (volume 21 was examined and swell factors of the various pits appear to have ^~° 2 a range of (-)8 to 77~. ,•<<~" ~' fry 4.: j. ~ , ,. ~, ~3 .~i -