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major source of recharge to the Wadge. Depth to water and water quality are <br />monitored at five sites within and adjacent to the permit azea. The varying amounts <br />of head measured at these wells again indicates that the major component of flow is <br />to the west. The amount of head within the Wadge, as in all the units in this area, <br />is a function of distance from the recharge area (anticlinal axis) and the type of <br />over/underburden present. <br />The Wadge coal is in a confined condition in most of the wells which have been <br />monitored. At well GW-42-S2W-SW, a downdip well due west of the south pit <br />azea, the Wadge appeazs to be semi-confined. While pumping this well, drawdown <br />was observed in an adjacent overburden completion well. This observation indicates <br />that there is, at this location, a hydrologic connection between the Wadge and the <br />overburden. <br />Aquifer tests were performed at two wells. One well failed during the test. The <br />transmissivity calculated at the other well was 0.03 ft~ per day, while storativiry has <br />been estimated to be on the order of 1 X IOA. <br />Four wells were sampled for water quality characteristics. Typically, the quality of <br />this water varies from place to place. Generally, sulfate, manganese and total <br />dissolved solids exceed both U.S. EPA and National Academy of Sciences <br />recommended drinking water criteria. These criteria may be found in Volume 3, <br />Tab 7, Table 7-13, Page 7-34 of the permit application. These waters are unsuitable <br />for use as a drinking supply, but may be used for livestock watering. These waters <br />also pose a high salinity hazard to intolerant plants, and therefore may be unsuitable <br />for use as irrigation water. <br />Wadge Coal Overburden <br />Six wells are used to monitor water quality and/or depth to water in the <br />Williams Fork Formation overburden above the Wadge coal seam. One of these <br />wells (We1140V1) was originally intended as a water level observation well. <br />Monitoring of this well was discontinued in October, 1986. With approval of PR- <br />02, the Division required SCC to resume monitoring this well for water quality. <br />This well will provide water quality and water level information in the Wadge Coal <br />Overburden for the south extension azea. If this well does not provide adequate <br />water quality data, SCC has committed to installing a functional monitoring well in <br />the Wadge Overburden within the south extension area. <br />The Williams Fork is a 50 to 500 feet thick sequence of sandstone, siltstone, shale, <br />and thin coal, including the Lennox Coal Seam. Ground water in the Williams Fork <br />tends to flow downdip. The movement of water and the horizontal extent of the <br />formation is limited by outcrops in the eastern and central parts of the permit azea. <br />Seneca II-W Findings Document 22 November 3, 1999 <br />