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Mine, Permit No. C-007-80, Proposed Decision and Findings of Compliance for 1,630 (sp)
<br />Permit Revision, August 26, 1985; "West Elk Coal Company, Mt. Gunnison No. 1 Mine,
<br />Permit C-007-8Q, Proposed Decision and Findings of Compliance for Permanent Lower
<br />Waste Pile Permit Revision, April 11, 1986", page 42; "West Elk Coal Company, Mt.
<br />Gunnison No. 1 Mine, Permit C-007-80, Proposed Decision and Findings of Compliance for
<br />Five Year Permit Renewal, October 10 1986" (un-scanned; archived), page 56]
<br />28. "No significant degradation in ground water quality is anticipated. Following mining, new
<br />springs, fed by water supplied by the accumulation of water in the underground workings,
<br />could form. At present, the water quality of these springs under worst-case assumptions
<br />would approximate the water quality of flooded mine workings at the Oliver Mine adit where
<br />total dissolved solids concentrations range between 1050 and 1900 mg/1(See CHIS-Affects
<br />(sp) to Surface Waters section)." ("Proposed Decision and Findings of Compliance for a
<br />Permit Renewal, West Elk Mine, C-80-007, December 16, 1992", page 58; Proposed Decision
<br />and Findings of Compliance for a Permit Revision (Jumbo Mountain Lease), West Elk Mine,
<br />C-80-007, October 21, 1994", page 49; "Proposed Decision and Findings of Compliance for
<br />Permit Revision No. 6 (Apache Rocks), West Elk Mine, C-80-007, January 26, 1996", page
<br />50; "Proposed Decision and Findings of Compliance for Permit Renewal No. 3, West Elk
<br />Mine, C-80-007, June 25, 1996", page 52; "Proposed Decision and Findings of Compliance
<br />for Permit Revision No. 7, West Elk Mine, C-80-007, May 5, 1997", page 54; "Proposed
<br />Decision and Findings of Compliance for Permit Revision No. 8, West Elk Mine, C-80-007,
<br />March 10, 2000", pages 57 and 58; "Proposed Decision and Findings of Compliance for
<br />Permit Renewal No. 4, West Elk Mine, C-80-007", page 60; "Proposed Decision and Findings
<br />of Compliance for Permit Revision No. 11, West Elk Mine, C-80-007, April 8, 2005", page
<br />71.1
<br />CDMG North Fork CHIS
<br />29. "Water quality data from water in the flooded workings is scarce. However, much of the data
<br />can be extrapolated from mine to mine. Water quality samples have been taken at the old
<br />Somerset, Hawk's Nest and abandoned Oliver No. 2 Mines. Somerset recorded TDS values
<br />ranging from 2000 to 3200 mg/1. CDMG staff recorded a TDS of 1642 mg/1 in the Hawk's
<br />Nest East Mine in 1987. TDS concentrations range from 1050 to 1900 mg/1 in the Oliver
<br />Mine...A projection of flooded workings water quality was made, in the unlikely event that
<br />water would discharge through the permanent seals into the North Fork of the Gunnison
<br />drainage. The quality of mine water may best be represented by data from the Oliver Mine
<br />adit. The Oliver Mine workings have been flooded for several decades and chemical
<br />equilibria are probably dominated by reduced conditions. Concentrations of selected major
<br />ions from the Oliver Mine adit water samples collected between ] 979 and 1982 indicated
<br />some seasonal trends in water quality... The Oliver Mine adit samples aze dominated by
<br />sodium and bicarbonate ions..." ["Cumulative Hydrologic Impact Study -North Fork of the
<br />Gunnison River-Revised 1/31/2001; Reviewed 11/10/2003]
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