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T , <br />There is one natural, intermittent spring that has been identified. It is <br />located at the toe of the mine portal bench neaz the former location <br />of Pond No. 2. The spring flow is now combined with the south <br />mine bench underdrain. <br />d. Groundwater Effects and Mitigation <br />The Blue Ribbon Mine does not expect to impact ground water, <br />because the coal outcrop of the E seam is about 80 to 100 feet above <br />the streambed of Hubbard Creek. In addition, the disturbed azeas <br />and underground mine areas are upland to the valley alluvial <br />materials. <br />The alluvium of Hubbard Creek is the only aquifer used within the <br />permit and adjacent areas. This aquifer supplied the water consumed <br />at the Blue Ribbon Mine. The mine utilized the only well located in <br />the Hubbard Creek alluvium as a water supply. This aquifer is an <br />isolated body of alluvium. Upstream and downstream of the mine, <br />the Hubbard Creek stream valley narrows and the stream flows over <br />resistant sandstone bedrock, effectively isolating the alluvial aquifer <br />in the azea of the mine. <br />The Rollins sandstone is the most significant regional bedrock unit <br />with potential as an aquifer in the North Fork Drainage Basin. This <br />unit outcrops in a narrow steep reach along Hubbard Creek about a <br />mile downstream of the mining operation. Recharge is limited <br />within the Hubbard Creek Drainage. No wells are completed in the <br />Rollins Sandstone below the mine in the Hubbard Creek Drainage <br />and the potential use is limited by the steep valley slopes below the <br />mine and the aquifers limited recharge area. The only potential <br />impacts to this aquifer would be a slight decrease in the quantity and <br />a slight degradation in the quality of waters recharging the aquifer. <br />No groundwater from the Rollins Sandstone will appear as mine <br />inflows within the Blue Ribbon Mine since the mine workings are <br />all topographically above the Rollins Sandstone. <br />T'he Blue Ribbon Mine may affect the quantity of ground water in <br />strata which overlies the mine workings. Only minor discontinuous <br />lenticular and interbedded sandstones have been identified through <br />drilling above the permit and adjacent areas. Most of these <br />sandstones are dry, while others support localized perched aquifers. <br />These strata were dewatered into the mine 1) through faults and <br />fractures, and/or 2) through conduits created by subsidence. <br />Fractured roof conditions produced mine inflows at the Blue Ribbon <br />Mine. These inflows were few, of short duration and involved <br />relatively minor amounts of water. The characteristics of these <br />inflows indicate that the source of water had a limited recharge area <br />22 <br />