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STATE OF COL~iv~~v DIVISION OF MINERALS AND GEOLOGY Deparimenl of Natural Resources 1311 Sherman St., Room 215 Ir~~~~ Denver, Coloaido SU2U3 I Phnne: 13031 ri66-3561 DEPARTMEM OF January 30, 1998 NATURAL RESOURCES Rov Rome James A. Kiger c°~e,°°. Sr. Environmental Engineer Tames S. lochhead Colowyo Coal Company L.P. E.ec°rre o~.e`~or 5731 State Highway 13 0~ s ~~ o~~e ~o~ Meeker, Colorado 81641 Re: Colowyo Coal Company 1997 Phase [Bond Release, C-81-019, Technical Adequacy Dear Mr. Kiger: The Division of Minerals and Geology (Division) has completed a preliminary technical adequacy review, on-site inspection, and evaluation of the subject 1997 Phase I Bond Release Application (Application). The Division finds the reclaimed areas of the West Pit and the East Pit, and the Section 16 Pit for the most part, in general compliance with the Permit. "In general compliance" means that landforms are appropriate, and that topography as described by contour lines aze within acceptable horizontal and vertical tolerances (considering information evaluated from the accuracy of 1 inch = 500 feet scale maps with 25-foot contour intervals, Global Positioning System (GPS) positioning conducted by the Division, and validation survey transects conducted by the Division). With regard to the Section 16 Pit reclaimed areas, however, the following exceptions aze noted: a) in the vicinity of state plane coordinates N335120 E1353200, the 7700-foot contour (Exhibit 1, 8/5/97, 1997 Bond Release Application) deviates from the approved post mine topo (Drawing 19, TR 42 Revision, 4/14/97) azimuth of approximately N30° W to approximately N30°E, resulting in a variance of over 100 feet in elevation (actual above approved) in the vicinity of coordinates N335700 E1353450. This suggests a deviation from the approved post-mining land form, projects potential impacts upon the planned location and configuration of the final East Pit ditch, and, if unabated, has the potential to affect spoil mass balance calculations. b) similar, but less severe, is the deviation of the 7800-foot contour from the vicinity of N33~ 100 E13~2340 to N336480 E1352200 (the actual elevation at N336480 E1352200 approximately 7~ feet above approved). Nearby contours are similarly affected. The variance diminishes to the west, as the 7900-foot contour actual approaches approved.