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Creek from 1982 through 2007 vary between 70 and 430 umhos/cm. There is no <br />indication the conductivity in downstream Hubbard Creek has increased since 1982. <br />The Blue Ribbon mine most likely did not impact groundwater because the coal outcrop <br />of the E-Seam is about 80 to 100 feet above the streambed of Hubbard Creek. In <br />addition, the disturbed areas and underground mine areas are upland to the valley <br />alluvial materials. The alluvium of Hubbard Creek is the only aquifer which was in use <br />within the permit and adjacent areas. This aquifer supplied the water which was <br />consumed at the Blue Ribbon Mine. The mine utilized the only well located in the <br />Hubbard Creek alluvium as a water supply. This aquifer is an isolated body of alluvium. <br />Upstream and downstream of the mine, the Hubbard Creek stream valley narrows and <br />the stream flows over resistant sandstone bedrock. <br />The Rollins Sandstone is the most significant regional bedrock aquifer in the North Fork <br />drainage basin. This aquifer outcrops in a narrow steep reach along Hubbard Creek <br />about a mile downstream of the mining operation. Recharge to this aquifer is limited <br />within the Hubbard Creek Drainage. No wells are completed in the Rollins Sandstone <br />below the mine in the Hubbard Creek Drainage and the potential use is limited by the <br />steep valley slopes below the mine and the aquifers limited recharge area. The only <br />potential impacts to this aquifer would be a slight decrease in the quantity and a slight <br />degradation in the quality of waters recharging the aquifer. No ground water from the <br />Rollins Sandstone will appear as mine inflows within the Blue Ribbon Mine since the <br />mine workings are all topographically well above the Rollins Sandstone. <br />The Rollins sandstone is a confined aquifer under piezometric head. The confining <br />shale layers and piezometric head should prevent any integration of water from the E- <br />Seam into the Rollins sandstone. There are about 600 feet of separation between the <br />E-Seam and the Rollins sandstone with numerous thick layers of coal and shale that <br />isolate the Rollins sandstone from the E-Seam. <br />The Blue Ribbon Mine might have affected the quantity of ground water in strata which <br />overlies the mine workings. Only minor discontinuous lenticular and interbedded <br />sandstones have been identified through drilling above the permit and adjacent areas. <br />Most of these sandstones are dry, while others support localized perched aquifers. <br />These strata could have been dewatered into the mine 1) through faults and fractures, <br />and/or 2) through conduits created by subsidence. <br />2 of 3 7/08