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POWDERHORN <br />COAL COMPANY <br />RECEIVED <br />1996 <br />May 14 , 19 9 6 pivision of P~inerals & Geology <br />Grand Junction <br />~rFX leesa <br />s/r~~ti~e <br />Mr. Dan Mathews <br />Environmental Protection Specialist <br />Colorado Division of Minerals and Geology <br />2148 Broadway, #C-5 <br />Grand Junction, CO 81503 <br />RE: Notice of Violation C-96-010, File C-81-041 <br />Dear Mr. Mathews: <br />iii iiiiiiiiiiiu iii <br />P.O. Boz 1430 <br />Palisatle, Coloratlo 61fi2fi <br />(970) 464-7951 <br />Fax (970)4647181 <br />In response to the subject NOV, this letter is being written to <br />meet the first step in the abatement requirements. Information <br />is being supplied to describe a what occurred and a proposed <br />correction. <br />Since mining resumed in the Roadside North Portal (RSN) in late <br />1995 water has been encountered while mining. Part of the water <br />goes out with the coal but the excess water has to be discharged <br />from the mine. The mining process generates fines that mix with <br />the water. Given enough time, most of the fines will settle out <br />before discharge. The exception to good settling occurs when <br />clays are mixed with the water. It appears that clay material is <br />being mixed with the water because the current 2 - 4 day <br />residence time undergound is not adequate. Prior to this <br />Violation we were seeing an increase in Total Suspended Solids <br />(TSS? Our 12/95, 1/96, 2/96 and 3/96 grab samples showed TSS <br />values of 4, 13, 14, and 17 mg/1 respectively. We had been <br />discussing the fact that a longer residence time and better <br />mixing needed to be done prior to the violation, but had not <br />arrived at a decision on the best solution. <br />The discharge that Barbara Pavlik, DMG, found on March 28, 1995, <br />was a cloudy brown color which is typical of clays. The lab <br />results showed 84 mq/1 for the sample which exceeded the 70 mg/1 <br />maximum TSS discharge allowed by our CDPS permit CO-0027146. When <br />averaged with other results for the quarter an of averaged 32 <br />mg/1 was calculated. The average was within the 35 mg/1 average <br />allowed by the permit. Two samples in April showed 19 mg/1 one <br />time and >2 mg/1 another. The variation in values indicates that <br />more uniform mixing would help to eliminated violations in <br />addition to the longer residence time. <br />