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., <br />:, <br />Water has been measured discharging from the old Victory No. 1 portal during <br />the spring of 1985 at up to 25 gallons per minute (gal/min). A water quality <br />sample taken in March, 1985 by the applicant indicates that this <br />sodium-magnesium/sulfate water is of extremely poor quality. This water <br />exceeds either EPA, Colorado Department of Health, or ML RD effluent limits for <br />iron, manganese, sulfate, and total dissolved solids. <br />An explanation for this quality difference is not readily available. Assuming <br />that the geochemical composition of the Menefee does not significantly differ <br />or either side of Coal Gulch, the difference in water quality is probably a <br />function of time and quantity of flow. <br />Subsidence fractures and trough depressions were observed above the <br />Victory No. 3 Mine at an elevation of about 7,340 (portal elevation is about <br />7,080', a difference of approximately 260'). These fractures parallel the <br />natural slope of the ridge crest, and are located about 60' below the crest. <br />Length of the fracture zone is 300'. <br />These cracks intercept runoff from the top of the ridge crest, and some <br />overland flow during precipitation events. This capture of surface drainage <br />can not account for the volumes of water being discharged from the abandoned <br />portals, therefore, another source of water must be present. <br />Possible sources of this water include: 1) Cliff House Sandstone, 2) Menefee <br />coal seams, 3) Perched Menefee aquifers. <br />In the Menefee it is postulated that perched aquifers exist due to the <br />interbedded and lenticular nature of the formation. The discharge from the <br />mines may be caused by the dewatering of a perched zone due to cracking or <br />fracturing of the low permeability lens. This would account for water <br />drainage, but a sustained flow of relatively large volumes of water from a <br />perched system on a yearly basis seems unlikely. <br />Water draining from Menefee coal seams is contributing some water to the <br />abandoned mines. Seeps were observed in April, 1985 issuing from <br />coal/sandstone-shale contacts along Highway 160 and at the Coal Gulch <br />highwall. At only one spot along the highwall was the flow large enough to be <br />measured; this spring was discharging less than 1 gal/min. The entire <br />highwall face appeared to be discharging less than 5 gal/min just after peak <br />flow in local streams, so it may be assumed that these seeps do not flow much <br />more than was observed. <br />Subsidence, as previously documented, has occurred at the Coal Gulch site. <br />Fracturing, bulking, and bed separation are all inter-related characteristics <br />of subsidence. <br />Fracturing reaches the surface at the mine site, while bulking and bed <br />separation may penetrate the lower Cliff House Sandstone. This would be <br />particularly true if the upper Menefee coal seam ("C" seam) has or will be <br />mined. <br />