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SL3 STATE OF ~OLOR~i~O DIVISION OF MINERALS AND GEOLOGY Department of Natural Resources 1313 Sherman St., Room 215 Dt'.nveq Colorado 80203 DIVISION O F Phone: (303) 866-3567 IbI l N E RA L FAX: (303) 832-8106 & April 1Q 2002 G E O L O G Y RECLAMATION MI NING•SAFETY Mr. Francis Lux P.O. BOX 682 Bill Owens Craig, CO 81625 Governor Greg E Watcher Executive Director Re: Lippazd Spring No. 2 Michael B. Long Division Director Dear Mr. Lux: I wanted to follow up on our telephone conversation yesterday. I'm not sure if I was very cleaz in my efforts to explain the hydrologic connections shown in Trapper Mining, Inc.'s cross section titled, "Lippazd Spring Cross-Section", dated February 27, 2002. Please refer to the cross-section as you read this letter. Enclosed please find the Division's hydrogeologist's conclusions regarding the potential impact of mining on the Lippazd No. 2 Spring. Based on the information presented to the Division, and the cross- section ofthe Lippard Spring No. 2 and reclaimed pits B and C submitted by Trapper Mining Inc. on March 8, 2002, the Division finds that the pits and the Lippard No. 2 Spring are not hydraulically connected. The shale layer which lies immediately above the F coal seam acts as aloes-permeability hydraulic barrier between the reclaimed pits and the Lippard No. 2 Spring. A second aquiclude, a low- permeability geologic layer, lies between the 2"d White Sandstone and the 3`d White Sandstone. I am enclosing water level data from the GLUX-1 water monitoring well. The GLUX-I well is the water monitoring well that is completed in the same aquifer as your well, the Lux Well, and as the Lippazd No.2 Spring. The water monitoring record of the GLUX-1 well goes back to 1988. I am also enclosing graphs of the GLUX-1 well and GE-1, GE-2 and GE-3 wells that you had asked about in our phone conversation. The GE wells are the monitoring wells located on the next ridge to the west of the GLUX-1 well, adjacent to the West Buzzard drainage. Please be aware that GE-1, GE-2 and GE-3 were completed in different aquifers than the GLUX-1 well. GE-1 was completed below the Q coal seam in the QR aquifer. GE-2 was completed below the H coal seam in the HI aquifer, and GE-3 was "completed in the F coal seam and the sandstone below" (Trapper permit, page 4-233), in the 2"d White Sandstone and the 3`d White Sandstone. The F coal seam has not been penetrated by any of the Trapper pits (Trapper permit, page 4-233). The GLUX-1 well and the Lux well are finished in the same stratigraphic unit, which lies over the F seam. If you refer to Figure A-5, "Water level elevation versus time for wells GE-1 and GE-2", this graph shows a typical aquifer reaction to mining. The QR aquifer and HI aquifer ground water levels drop rapidly in 1977 at the onset of mining in the B pit. The ground water level remains low while mining continues, then rapidly raises in elevation beginning in 1985, which correlates to the back-filling and reclamation of B pit. The ground water continues to recover even I S years after the pit has been backfilled. The "Water-level elevation versus time for wells GE-3, 81-03A and GLUX-1" graph shows the same general pattern for monitoring well GE-3.