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III IIIIIIIIIIIII III <br />999 <br />POWDBRHORN COAL COMPANY <br />Pond No. 1+2 - Unit Train Loadout <br />Certification <br />i, Larry M. Reschke, PE 19691, hereby certify that combined Pond <br />No. 1+2 located at Powderhorn Coal Company's Unit Train Loadout <br />Area meets or exceeds the design requirements of plans submitted <br />to and approved by the Colorado Division of Minerals and Geology. <br />Design information can be found on Pages wW-37 thru 39, Appendix <br />WW, Volume 7; Exhibit X, Volume 2; and Item 2, Volume 7 of our <br />Mining and Reclamation Permit Application No. C-81-041. ..This <br />certifications covers capacity and the emergency spillways. No <br />embankment certification was done because it was excavated below <br />grade. <br />Ponds 1 and 2 were installed in 1978 with 36" CMP emergency <br />spillways. Pumping was permitted as the means of primary <br />dewatering. The spillway configuration was reevaluated in late <br />1994 and a proposed decision was made by DMG on January 30, 1995 <br />for a new design. The new design involved connecting the two <br />ponds with a channel and using both culverts as the emergency <br />spillway. Primary dewatering will continue to be pumping. A 15' <br />wide trapezoidal channel was installed in March 1995 which <br />exceeds the capacity of the V-ditch design. The attached drawing <br />shows the contours of the pond as taken from airphotos in 1980 <br />and the spring of 1995, and survey done May 16, 1995. The <br />drawing also shows the inlet and outlet structures on the <br />combined pond. The attached stage capacity diagram shows the <br />existing capacity and the design capacities. <br />rY7I~~~~Q~L® <br />JUN ~~ ? ~~^~ <br />"~~~,~ <br />'~, <br />f9F ~~~~ <br />~~~- r~~~~j / l <br />oa~~ ~,, <br />