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Tab 15. Each year following snowmelt, any additional spoil springs discharging 5 gpm <br /> or more are documented, monitored in spring and fall, and reported in the Annual <br /> Hydrologic Report for the year. <br /> Each of the identified aquifer zones is hydraulically discontinuous with the units above <br /> and below. Therefore, each aquifer is discussed below as a separate entity. <br /> Hubberson Gulch Alluvium <br /> The alluvium in Hubberson Gulch occurs in the lower reaches of the gulch in and <br /> adjacent to the permit area. Depth to water data indicates that the aquifer varies from semi <br /> confined to water table conditions. The amount of head, if any,is generally less than 5 feet. <br /> Water quality analyses of two alluvial wells indicate that these calcium-bicarbonate type <br /> waters do not meet U.S EPA drinking standards. Manganese, sulfate, TDS, and chromium <br /> are exceeded standards. These waters do meet stock watering criteria, and may be used <br /> for irrigation dependent upon crop and soil characteristics. <br /> Groundwater quality concentrations remained within the agricultural standards set. TDS <br /> concentrations at WHAL7-2 remains within the historical trend as increasing. <br /> Dry Creek Alluvium <br /> One well(DCAL-02),is monitored in the Dry Creek alluvium. A decreasing ground water <br /> trend is consistent with the historical range. Water quality concentrations are within CDPHE <br /> agricultural use standards with the exception of Manganese. TDS is within the historical <br /> range. <br /> Wadge Coal Overburden <br /> Three wells are used to monitor groundwater water quality and/or depth to water in <br /> the Williams Fork Formation overburden above the Wadge coal seam. The Williams Fork <br /> is a 50 to 500 foot thick sequence of sandstone, siltstone, shale, and thin coal, and <br /> includes the Lennox Coal Seam. Ground water in the Williams Fork tends downdip. The <br /> movement of water and the horizontal extent of the formation are limited by outcrops in <br /> the eastern and central parts of the permit area. Generally, the Williams Fork presents as <br /> unconfined; however, locally or seasonally, the formation may exhibit semi-confined <br /> conditions. Seasonal fluctuations indicate the recharging and dewatering of a perched <br /> aquifer within the formation. <br /> Groundwater levels show an increasing trend and water quality concentrations are within the <br /> CDPHE agricultural use standards. Water quality analyses indicate that the magnesium- <br /> calcium bicarbonate water with seasonal excursions levels of iron and TDS is suitable for <br /> stock watering and irrigation of salt tolerant plants. <br /> Wadge Coal <br /> The Wadge coal comprised the principal seam of interest within the original permit area, <br /> and was also mined in the south extension area. It is typically 11 to 13 feet thick, <br /> except where split by partings. The Wadge coal outcrops along the east side of the permit <br /> area. These outcrops and perhaps a portion of the overburden east of the permit area are <br /> thought to be the major source of recharge to the Wadge. Depth to water and water <br /> quality are monitored at three wells within and adjacent to the permit area. The varying <br /> amounts of head measured at these wells indicate the major component of flow is to the <br /> west. The amount of head within the Wadge, is a function of distance from the recharge <br /> area (anticlinal axis) and the type of over/underburden present. <br /> Page 19 of 37 <br />