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P~~~fi~.-~ ~~e III IIIIIIIIIIIIIIII 999 STATE OF COLORADO 41VISION OF MINERALS AND GEOLOGY Department of Natural Resources 1313 Sherman St., Room 215 Denver, Colorado 80203 Phone: (303) 866-3567 fAx: (303)832-8106 November 29, 2001 ~~ ~ DIVISION OF~ MINERALS:" GEOLOGY RECLAMATION MINING•SA FETY Tanya Hammond Bill Owens Powderhom Coal Company Governor P Q BOx 1430 Greg E. Walther . . Executive Director Palisade, CO 81526 Michael a. Long Division Director RE: Roadside North and South Portal Mines 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 [o ensure compliance with recently amended impoundment regulations. Water Quality Analyses 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 tattier than dissolved species concentration. Based on the most recently provided data, in which selected parameters were analyzed using both methods, it would appear 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 theminewater system that supplied water to the wash plant, which shut down in late 1999. In 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 OOI, to supplement the mainminewater discharge system (Outfall 002) by routing 75 gpm out through 001. The water now being discharged fromOutfall 001 is water which would previously have mixed with other water downgradient in the mine, and eventually would have discharged via(httfall 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 requrements, I will let you know. We are not requesting any modifications to the approved analysis procedures for Powderhom at this time.