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iiiiiiiuiiiiiii-iii 999 STATE OF COLORADO 41V1510N OF MINERALS AND GEOLOGY Depanmenr of Natural Resources 1313 Sherman SI., Room 215 Denver, Colorado 80203 Phone: 1303) 866-3567 FAx: 1303) 832-8106 November 29, 2001 Tonya Hammond Powderhom Coal Company P.O. Box 1430 Palisade, CO 51526 RE: Roadside North and South Portal Miaes Water Quality Analyses and Impoundment Certifications Permit C-1981-041 Dear Ms. Hammond We have reviewed the recently submitted 001 Discharge Analyses we requested, and have made the following observations. Also by this letter, we are advising you of measures you need to take to ensure compliance with recently amended impoundment regulations. Water Quality Analvses ~~ DIVISION OF MINERALS GEOLOGY RECLAMATION MINING•SAFETY Bil I Owens Governor Greg E. Walther Ezecutwe Director Michael B. Long Dwision Director We have reviewed the analyses for the additional water sample you provided for Discharge 001, which we had requested based on review of the 2000 AHR. Our concern had been that the rather dramatic differences for certain parameters between August 1999 and August 2000, might have been wholly or partially due to an increase in the amount of sediment in the water, since the analyses were based on total species concentration rnther than dissolved species concentration. Based on the most recently provided data, in which selected parameters were analyzed using both metltods, it would appeaz that this was not the case. The differences between total and dissolved values are very small in comparison to the differences between values from samples prior to August 2000 and subsequent data. The data appear to reflect a real difference in water quality. The change in water chemistry is likely due to a change in the source of the discharge water. As noted on page 2 of the 2000 AHR, Outfall 001 was historically used to discharge overflow from dteminewater system that supplied water to the wash plant, which shut down in late 1999. Tn the spring of 2000, a discharge pipe was installed from the No. 2 South Mains (at the far upper end of the mine workings) to outfall 001, to supplement the mainminewater discharge system (Outfall 002) by routing 75 gpm out through OOI. The water now being discharged fromOutfall OOl is water which would previously have mixed with other waterdowngradient in the mine, and eventually would have discharged via0utfa1l 002. My understanding is that our staff hydrologists in Denver will be evaluating whether any policy changes are warranted with respect to "dissolved species" versus "total species" analytical requirements for minewater discharge and other surface water sampling. If it is determined that changes are warranted that would impact the Powderhom permit requirements, 1 will let you know. We are not requesting any modifications to the approved analysis procedures forPowderhorn at this time.