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Groundwater <br />Two aquifers exist within the permit area: alluvial deposits associated with the stream of <br />Trout Creek and bedrock groundwater stored in the Tow Creek Sandstone. Alluvial <br />deposits line Trout Creek within the permit and adjacent areas. The nearest alluvial <br />well downstream of the mine is over a mile and a half away. <br />Monitoring wells controlled by adjacent mines show that the only regional ground water <br />aquifer existing within this permit area is the Tow Creek Sandstone. The Tow Creek <br />Sandstone is separated from the coal seam that was mined by 600 feet of interbedded <br />sandstones, shales and siltstones. These units have a very low vertical permeability, <br />except possibly where faulted. <br />Sunland Mining Corp, conducted a spring survey to observe other possible ground water <br />aquifers in the permit and adjacent area. The spring survey (Map Exhibit P of the <br />permit application) identified several springs in and adjacent to the permit area. The <br />springs within the permit area and those to the northwest near Middle Creek do not <br />appear to be fault or fracture controlled. Rather, they appear to be stratigraphically <br />controlled, perched aquifers. This conclusion is substantiated by the low electrical <br />conductivity indicating a short flow path between the recharge and discharge areas. <br />These springs, located one-half mile northwest of the mine workings, are the only springs <br />that could have possibly been impacted by mining. Some minor effects to the quantity of <br />flow from these springs might be realized due to subsidence above the workings. To <br />date, no problems have been noted with these springs. If a worst-case analysis assumes <br />that all of the flow from the springs would be interrupted, the resultant flow reduction in <br />Middle Creek would be 0.02 cubic feet per second. This amount is insignificant to the <br />flow of Middle Creek. <br />The only regional aquifer within the permit area is the Tow Creek Sandstone which is <br />over 600 feet below the coal seam being mined. The Trout Creek Sandstone, another <br />regional aquifer in the general area, has been eroded from above the coal seams being <br />mined. Because of the low permeability of the interbedded shales and siltstones of the <br />Iles Formation, the Tow Creek Sandstone is recharged primarily where it subcrops in the <br />stream bottoms. The nearest subcrop of the Tow Creek Sandstone to the permit area is <br />approximately one mile upstream of the mine. Low vertical permeability results in the <br />formation of perched aquifers in local lenticular strata. These perched aquifers recharge <br />and discharge within a short distance forming small seasonal springs and seeps. <br />Sunland Mining Corporation conducted a mine inflow study. This information is <br />provided on Map 1 of the permit application. This map shows that the mine inflow is <br />restricted to floor seeps occurring in Fault Block No. 1 and the total rate of water <br />production underground is 40 gallons per hour. An underground inspection of the mine <br />was conducted by the Division which confirmed that absolutely no water was being made <br />Apex No. 2 Mine, C-81-011 6 May ~, 1993 <br />