2008-02-19_GENERAL DOCUMENTS - C1981047

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r In October 1977, Centuries Research, Inc. conducted a cultural resource survey ofthe Blue Ribbon proposed mine site. The survey found the area to contain no cultural resources. The State Historical Preservation Officer concluded that the :Blue Ribbon Mine would not impact significant cultural resources, this was again confirmed on June 12, 1997. Hydrologic Balance -Rule 2.04.5, 2.04.7, 2.05.3(4), 2.05.6(3) and 4.05 Groundwater information can be found in the permit document in Section 2.04.7. The locations ofmonitoring sites can be found in Exhibit Z. A description of groundwater occurrence and mining impacts on groundwater within the permit and adjacent areas can be found in the "Probable Hydrologic Consequences" section of this document and the "Cumulative Hydrologic Impact Study" document for this mine area. The coal outcrop of the E seam, which Blue Ribbon mined, is about 80 to 100 feet above the stream bed of Hubbard Creek. Tlie disturbed areas and underground mine areas lie at a higher elevation than the alluvial deposits. The major portion of the mine workings are above the level of Hubbard Creek, so the mine never experienced inflows directly related to water flowing in Hubbard Creek. The alluvium of Hubbard Creek is the only aquifer within the permit and adjacent areas. This aquifer supplied the water consumed at the Blue Ribbon Mine. This aquifer is an isolated body of alluvium. Upstream and downstream of the; mine, the Hubbard Creek stream valley narrows and the stream flows over resistant sandstone bedrock, effectively isolating the alluvial aquifer in the area of the mine itself. The Rollins sandstone is the most significant regional unit with potential to be considered a bedrock aquifer in the North Fork drainage basin. This unit outcrops in a narrow steep reach along Hubbard Creek about a mile downstream of the mining operation. Groundwater recharge to this unit is limited within the Hubbard Creek drainage. The potential use of this unit as an aquifer is limited by the steep valley slopes below the mine and the its limited recharge area. No groundwater from the Rollins Sandstone appeared as mine inflows within the Blue Ribbon Mine, since the mine workings are all stratigraphically above the Rollins Sandstone. The E coal seam dc-es not qualify as an aquifer. The mine workings were nearly dry, except in a few areas of fracturing. Mine inflows documented in the annual hydrology report were described as minor or as "drips" or "wet area" except for specific inflows of 4.5 and 2 gallons per minute . Water pumped to the surface ranged from 38.3 to 86.8 gallons per minute in 1985, but it's not clear how much of that was process water that had originated on the surface. Recent inflows in the Oxbow Mine nearby were 114 gpm in the B-seam and 15 gpm in the C-seam. In general, there remains no apparent issue with groundwater. Surface water information can be found in Section 2.04.7 of the permit document. The locations of monitoring sites can be found in Exhibit Z. A description of surface water occurrence and mining impacts on surface water within the permit and adjacent areas can be found in the "Probable Hydrologic Consequences" section ofthis document and the "Cumulative Hydrologic Impact Study" document for this mine area. Hubbard Creek runs through the permit area between the mine bench and the former location of the coal stockpile and is the only tributary of the North Fork of the Gunnison which may be affected by operations at 4