Laserfiche WebLink
eh <br />ESPEY, HUSTON b ASSOCIATES, INC. <br />origin (Collins, 1976). Consequently, the iron sulfide percentage is never greater <br />than 0.107 and neither marcasite or pyrite (FeSZ) are present in quantities that <br />should pose a potential for significant acid mine drainage from either the mines <br />proper or the waste dump facilities. <br />2.3 DESCRIPTION OF OVERBURDEN <br />As stated previously, the coal lands included within the described <br />boundaries of Northern Coal Company's mine plan azea and planned for subsurface <br />coal mining contain coal deposits and encompassing sedimentary strata of the <br />Williams Fork Formation. Minor coal beds are present in the IIes Formation, which <br />conformably underlies the Williams Fork, and aze approximately 800 feet below the <br />lowest coal seam to be mined, the G seam. Along the northern border of the mine <br />plan azea, the base of the Williams Fork (top of Trout Creek Sandstone, IIes <br />Formation) is deepest at 2,965 feet. At this location the lowest seam to be mined <br />(G seam) is at 2,355 feet. <br />Rock classifications within the Williams Fork consist of interstratified <br />terrigaaous clastic sediments including thick, moderately cross-bedded, fine- to <br />medium-grained sandstones, laminated siltstones and mudstones, dark bedded shales, <br />thin clays, cazbonaceous shales and authochthonous coals of varying thickness and <br />character of quality. All of the sedimentary units, except the coals, occur as <br />laterally discontinuous beds, which, utilizing wire-line geophysical methods, cannot <br />be traced over any large azeal distance. A summary of the chemical analyses of the <br />roof and floor lithologies of each seam aze presented in the appendix along with the <br />potential alkalinity and clay content of the strata above and immediately below <br />each coal bed to be mined. <br />Drill holes completed for the purposes of monitoring and observing the <br />relationship of water beazing horizons to the coal seams strongly evidence that the <br /> <br />F-16 <br />