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s :., . . blue ® ribbon coal company Certification of Blue Ribbon Coal Co.'s #1 Pond blue ribbon coal company p.o. box 58 tleha, Colorado 81416 (3031 87a 7561 July 8, 1985 This certification is being done to meet the requirements of Colorado Mined Land Reclamation Board's Rule 9.05.6(7). This certification is a re-certification of the Blue Ribbon Coal Company's #1 Pond which was originally certified June 1, 1983. The pond was changed as a result of a technical. revision to stabilize the mine bench, therefore this certification. The description of the changes may be found in Appendix 1B to the Bench Stabilization Technical Revision submitted September 6, 1984. I,Larry M. Reschke, PE, a Registered Professional Engineer in the State of Colorado am doing this certification. I am the Mine Engineer at Blue Ribbon Coal Company and Grand Mesa Coal Company. I have had various experience at these two mines with supervision and inspection of earth work. The Pond modifications consisted of relocating the discharge structures, increasing the embankment height on the south end and filling in the southeast end of the pond which was shallow and swampy. The pond embankment was cut at the location of the low level drain and the pond was drained. The new drain was installed September 28,1984. A concrete cutoff collar was poured around the 8" Schedule 90 PVC pipe and the dirt was recompacted in the lower portion of the trench with a gas powered compactor and in the upper portion of the trench with a 615 Cat compactor. The embankment height was increased 18 to 24" around the south end of the pond using material from the bench toe excavation during the first 2 weeks in November 1984. This material was compacted in 6 - 12" lifts with a Cat 815 compactor. A second trench was dug for the primary spillway and dewatering device This 8" Schedule 40 Pvc pipe was installed November 12, 1984. The emergency spillway was dug January 22, 1985, but the rip-rap was not installed until May 3, 1985. The pond dimensions were taken May 28, 1985, and the spillway elevations were checked. The volumes and elevations of spillways are shown on the attached diagram. The bench stabilization project required storing part of the excavated colluvial material in the pond, therefore the actual dima~si~ns with dirt in the pond and the anticipated dimensions once the dirt is removed are shown. The actual dimensions are suitable to cover the needs for sediment control without further excavation. I certify that the #1 Pond has been modified under my direct supervision and that to the best of my knowledge and belief the pond is structurally sound and that it has the volumes shown on the attached diagram.