2008-03-20_GENERAL DOCUMENTS - C1981019

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STP,TE OF COLORADO DIVISION OF RECLAMATION, MINING AND SAFETY Department of Natural Resources 1313 Sherman St., Room 215 Denver, Colorado 80203 Phone: (303) 866-3567 FAX: (303) 832-8106 COLORADO DIVISION O F RECLAMATION MINING - &- SAFETY Bill Ritter, Jr. Governor TO: Jim Stark ~ FROM: Kent Gorham Harris D. Sherman Executive Director CC: Sandy Brown, David Berry Ronald W. Cattany RE: Colowyo East Pit Reclamation, #C-81-019 (Updated) Division Director Date: March 20, 2008 Natural Resource Trustee As you may recall, I circulated a memo in May 2007 detailing my observations and concerns regarding the East Pit reclamation taking place at the Colowyo Mine. Within the last few months the Division has met with Colowyo and within the last week, Colowyo has submitted the 2007 Annual Reclamation Report documnting reclamation work completed in 2007. Below please also find the text (in italics) of my memo from May 2007 and additional comments, corrections, or updated information where appropriate. Colowyo is close to finalizing responses to TR-63, Revising the Post-Mining Topography. This revision also modified permanent channel design for a number of the planned permanent drainage channels, based on a generalized design included as Exhibit 7H of the revision. East Taylor Ditch, Streeter Gulch Ditch, West Pit Ditch, Taylor Ditch, Buckskin Draw Ditch, and North Tributary of the East Pit Ditch were also the subject of TR-63. All other permanent ditches, including Prospect Ditch, and Final East Pit Ditch were not included in TR-63. As you are aware, 1 recently conducted a partial inspection at the Colowyo mine site, accompanied by Tay Tonnozzi of Colowyo Coal Company. Results of my inspection are documented in an inspection reported dated 4/27/2007. The focus of the inspection was to check the grade in the lower portion of the Prospect permanent drainage and investigate a seep in the same general area that 1 initially identified on aerial photos taken in May 2006 of this area. 1 have some concerns that I wanted to document outside the context of that inspection report. First, based on my field measurements and as documented in the inspection report, the Prospect Ditch drainage profile may be steeper than approved. 1 used a field clinometer and paced off distance so my field check is likely less accurate than a professional survey. Mr. Tonozzi indicated that Colowyo had already surveyed the drainage. 1 would recommend that Colowyo submit apost-mining, as-built drainage profile overlaid on the planned post-mining profile for this drainageway. This should be done now before topsoil and riprap is added to this area in the event there are any problems or issues to address before finalization of the general area. • 1 recommend that we get as-built information for Prospect drainageway as soon as possible. Text from my April 2007 inspection (in italics); Regrading to rough grade is nearing completion in the Prospect Ditch watershed of the former East Pit. Technical Revision #63 (TR-63) modified the post-mining topography and drainage in this area. Postmining permanent drainage profiles are shown on Map 33, revised and certified 2/13/07. Plan view of Phis drainage is shown on Map 41, Watershed Boundaries for Hydrologic Modeling, revised and certified 2/14/07. Grade Office of Office of Mined Land Reclamation Denver Grand Junction Durango Active and Inactive Mines