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~~ /DIVISION OF MINERALS AND GEOLOGY Department of Natural Resources 7 313 Sherman St., Room 215 Denver, Colorado 80203 FAX~1303) 83868106 7 ECEN ~.~Ii,. FEB 112002 Division of Minerals anv peviob ~ebruary 7, 2002 Carl Dismant /~achelor Silver Mines Co. P.O. Box 965 Ouray, CO 81427 STATE OF COLORADO ~~L~': ~.-14go-t}~ '~ ya~O~~: Br.Y-Pi{av' c L}~-~v~K'lt~ DIVISION O F MINERALS GEOLOGY RECLAMATION MINING•SAFETY Bill Owen: Governor Greg E. Walther Executive Director Michael 8. Long Division Director Re: Bachelor Mine, Khedive Portal, Permit M-1980-171, Corrective Action and Water Sampling Proposal. Dear Mr. Dismant, I have reviewed the written proposal to implement a quarterly sampling program, to check for impacts to water quality in Dexter Creek from the Khedive Mine. This was sent to me by Brian Briggs of American Mining and Consulting, Inc. on your behalf. I have a couple of comments about the sampling program, in the paragraphs below. The information describing the discharge as "subsurface" seemed tentative to a small degree, but that is acceptable at this point in time. Once the site is accessible this spring, the flow path of the discharge may be determined and more accurately characterized. At that time, its location should be drawn on a permit map, and fully described through its surface and subsurface segments. The extent of the dump material (as opposed to the native hillside) over or through which the flow passes should be shown on the map. Filially, any noted seepage should be identified on [he map and described for the file. If the flow of the discharge is determined to be surface water all the way to Dexter Creek, which is outside the permitted area boundary, we should plan to include the Water Qulaity Control Division in our discussions. The sampling locations should be identified, by depicting them on a map and description for the file. The locations should be marked somehow on the ground to ensure consistency hr sampling. If any seepage is found downhill or downgradient from the lowest location of discharge's surface flow, then the lower sampling location must be below that feature. The quarterly schedule for sampling appears adequate. The springtime sample will be the most valuable, in that it typically shows worse water quality than the other seasons. Therefore, please ensure that you do not miss the spring sampling time. You have suggested that data be collected over a course of three years. I will be discussing your proposal with one of our Denver staff, to verify whether we need to continue beyond one or two years of quarterly sampling. It might depend on how the sampling results turn out, and cannot be decided yet, but I will let you know. The parameters you propose should be analyzed are few, and I cannot say if the set is sufficient. I will also discuss this with our Denver staff, and will let you know. Regardless of which parameters are measured, the detection limits must be sufficient. Please let me know if you have questions about them.