Laserfiche WebLink
• 2.04.7 <br />sources, including floor rock, roof seeps and faults. No individual source <br />contributed more than 1 gpm. Faults are expected to yield more flow than <br />either roof seeps or floor rock in underground mining due to the secondary <br />permeability created by the fractures within the shear zones. Storativity <br />within shear zones is usually high which results in a higher initial inflow when <br />the fault is first encountered by underground mining and eventually slows to <br />a rate dictated by the permeability of the shear zone rock or slower up <br />gradient medium. A reasonable conclusion to the low flow in the faults being <br />measured at the Bowie #1 Mine is that the faults are not hydraulically <br />connected to a perennial stream or significant groundwater aquifer. The <br />small amount of water flowing from these faults could be originating from <br />connections with the near surface water bearing colluvium and/or ephemeral <br />drainages or any perched water zone, if present, within the contacted <br />bedrock. <br />Other mines in the North Fork Valley experience mine water inflows. The <br />Hawksnest mine which was developed in the E-Seam was reported to be <br />virtually dry. The Oliver No. 1 mine, developed in the D-Seam, is currently <br />• discharging water from its abandoned openings at the rate of 10 to 15 gpm. <br />The Oliver No. 3 mine which was developed in the E-Seam is apparently not <br />discharging water. Based on a mine inflow study dated September 21, 1990, <br />the now sealed Somerset Mine had an estimated inflow of 235 gpm. The <br />Somerset Mine measured inflow from faults during its operation ranging from <br />120 gpm to less than 0.5 gpm. The fault flow of 120 gpm was below in <br />elevation, down dip and in close proximity of perennial Hubbard Creek and <br />possibly contacted the creek creating a conduit of inflow into the old mine <br />workings. The majority of the remainder of the reported flow in the Somerset <br />Mine originated from numerous roof cracks scattered throughout the area of <br />the old mine works below, down dip, and in close proximity of the creek. The <br />Sanborn Creek Mine, in the early stages of development had a mine inflow <br />of about 17 gpm until development encountered a fracture which increased <br />the mine inflow to 250 gpm which eventually slowed to 100 gpm. The <br />Sanborn Creek Mine reported a total mine inflow for the 1995 reporting year <br />of 254 gpm, of which the fracture contributes 88 gpm. It is important to note <br />that the Sanborn Creek Mine is the only mine in the valley operating its <br />underground mine both lower in elevation, down dip and in close proximity <br />of the North Fork of the Gunnison River and the vast majority of their inflow <br />is attributed to the hydraulic contact with the river and/or associated <br />. alluvium. The old King Mine workings on the Bowie property is apparently <br />not discharging water. <br />PR-03 2.04 - 39 - 5/99 <br />