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<br />Four wells were sampled for water quality characteristics. Typically, the <br />quality of this water varies from place to place. Generally, sulfate, <br />manganese and total dissolved solids exceed both U.S. EPA and National Academy <br />of Sciences recommended drinking water criteria. These criteria, which are <br />generally accepted by the water industry, may be found in Volume 3, lab 7, <br />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 <br />waters also pose a high salinity hazard to intolerant plants, and therefore <br />may be unsuitable for use as irrigation water. <br />Wadge Coal Overburden <br />Six wells are used to monitor water quality and depth to water in the <br />Williams Fork Formation overburden above the Wadge coal seam. The Williams <br />Fork is a 50 to 500 feet thick sequence of sandstone, siltstone, shale, and <br />thin coal, including the Lennox Coal Seam. <br />Ground water in the Williams Fork tends to flow down dip. The movement of <br />water and the horizontal extent of the formation is limited by outcrops in the <br />eastern and central parts of the permit area. <br />Generally, the Williams Fork is found to be in an unconfined state, however, <br />locally or seasonally the formation may exhibit semi-confined conditions. <br />Seasonal fluctuations are probably the result of recharging and dewatering a <br />perched aquifer within the formation. <br />Although aquifer tests were not performed on the overburden at the site, <br />aquifer characteristics have been extrapolated from Colorado Yampa Coal, <br />located about 15 miles southeast. Data obtained from these tests indicate <br />that transmissivityy values for the overburden could range from 3 to 20 gallons <br />per day per foot (0.4 to 2.7 FT2 per day), while storativity may vary from <br />1 x 10-2 to 1 x ]0-5 as local conditions change. <br />One well was sampled for water quality. Analyses of this magnesium - calcium <br />bicarbonate water shows elevated levels of iron, manganese, TDS, and zinc. <br />The high zinc values are probable due to contamination from the galvanized <br />well screen. The high iron, TDS and manganese values preclude this water as a <br />drinking supply. Williams Fork water is suitable for stock watering and <br />irrigation of salt tolerant plants. <br />Hubberson Gulch Alluvium <br />The alluvium in Hubberson Gulch occurs in the lower reaches of the gulch in <br />and adjacent to the permit area. <br />Six alluvial completion wells are used to monitor depth to water in the <br />alluvium, while two of these are used as water quality sample sites. Depth to <br />water data indicates that these wells may vary from semi-confined to water <br />table conditions. <br />- 15 - <br />