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<br /> <br />Alluvial Aquifers <br />The Lightner Creek alluvial system is located approximately 1 mile north, and <br />1 mile east of the proposed mine site. This alluvial aquifer receives <br />recharge directly from precipitation, snowmelt, stream flow and ground water. <br />Alluvial flows parallel to Lightner Creek as it flows to the southwest. The <br />alluvial aquifer is most extensive in width to the north, and thins eastward <br />as the canyon becomes more narrow. <br />The applicant states that alluvial wells are completed adjacent to Lightner <br />Creek, indicating that this is a fairly reliable source of water for domestic <br />use. <br />Colluvial Aquifer <br />A relatively discontinuous seasonal Colluvial flow system is found in Coal <br />Gulch and it's tributaries. This Colluvial flow system is derived from <br />springs along slope failures in Coal Gulch. These slope failure complexes are <br />expressed as rotational and block slumps resting on the floor of the gulch at <br />stream level. The slope failures are extremely common above the mine site in <br />Coal Gulch and it's side canyons. The hillside to the west of the proposed <br />mine facilities area exhibits evidence of yearly movement, which may be the <br />result of the stream diversion cutting the toe of older failures. <br />The Colluvial materials intercept flow from snowmelt runoff, thus creating <br />many unconfined aquifer systems which discharge at their lowest point; the <br />stream channel. <br />Each of these failures exhibited ground water flow in the form of seeps and <br />springs in April and May of 1985. Surface water intercepted by the slumps and <br />discharged as springs into the creek accounts fora significant amount of Coal <br />Gulch flow during the late spring. <br />The majority of these slumps are depleted by early summer, at which time Coal <br />Gulch does not flow, or becomes intermittent. <br />Subsidence Related Flow <br />A localized flow system is found in the permit area. Subsidence fracturing, <br />due to coal extraction of the "A" seam from the Victory No. 3 and Victory No. <br />1 Mines, is seen at the surface above Coal Gulch. Subsidence is expressed as <br />both trough depressions and long fracture zones at the surface. It is <br />postulated that rubbilization has occurred through the upper Menefee, and into <br />the lower Cliff House. Surface fractures and depressions intercept overland <br />flow from precipitation and snowmelt runoff, and divert this flow into the <br />abandoned mines. Rubbilization (bulking), dependent upon extent, is capable <br />of diverting normal ground water flow from the upper Menefee and lower Cliff <br />House toward the abandoned mines by creating large areas of high vertical and <br />moderate horizontal permeability. <br />