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STATE OF COLORADO DIVISION OF MINERALS AND GEOLOGY Department of Natural Resources 1313 Sherman St., Room 215 Denver, Colorado 80203 Phone: (303) 866.3567 FA%: (303) 832106 February 23, 2006 Jim Stover, P.E. J. E. Stover & Associates P.O. Box 60340 Grand Junction, CO 81506 RE: Blue Ribbon Mine, Permit No. C-81-047, Minrec, Inc. 2005 Annual Hydrology Report, Adequacy Review Deaz Mr. Stover: COLORADO DIVISION OF MINERALS GEOLOGY 0.ECLAMATION•NINING SAf ETY•ECIENCE gill tTven$ Governor Russell George Executive Dimctor Ronald W. Canany Division Director Natural Resource Trustee The Colorado Division of Minerals and Geology (Division) has finished its review of Minrec's submittal of the 2005 Annual Hydrology Report (AHR) for the Blue Ribbon Mine. Based on this report, the Division agrees with Minrec's conclusion that there have not been any adverse effects to the hydrologic regime due to the reclaimed mine site. In addition, the Division finds that the required hydrologic sampling was performed in 2005. The data in the 2005 AHR support the predictions contained in the Probable Hydrologic Consequences section of the permit application. Review of the water quality data in the 2005 AHR shows that mining has not adversely affected Hubbazd Creek. In three of the four quarters of 2005 where Hubbard Creek was sampled, conductivity was lower than the historic average. Also, in three of the four quarters of 2005, the conductivity at the down gradient Hubbazd Creek site was actually lower than that at the upgradient Hubbard Creek site, while conductivity was the same at both sites for the remaining quarter. Examination of the historic data presented in the graphs for the bench piezometers seems to indicate that the 2005 water levels in the piezometers are approaching those water levels just prior to the drought yeazs, perhaps due to increased precipitation in the second quarter of 2005, as evidenced by the much larger than average water flow in Hubbard Creek for that quarter. Concurrently, rather than having no dischazges from the three underdrains like in the last few years, there was a small amount of dischazge out of the north underdrain for each of the four quarters of 2005. Perhaps the underdrain dischazges are beginning to return to normal as well. The Division has Three comments concerning the hydrologic monitoring program as described in the permit application. Please submit these changes through a minor revision. Office of Office of Colorado Mined Land Reclamation Active and InaRive Mines Geological Survey