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eams being mined at Trapper Mine are all in the upper Williams Fork member and are called, in <br />descending order, the H, I, K, L, M, Q, Q-rider, R and R-rider. <br /> <br />Surface Water Hydrology <br /> <br />Drainages within and adjacent to the permit area (on the north facing slope) run south to north <br />down the slope in a dendritic pattern. Within the permit area are portions of the following <br />drainages, listed from west to east: Buzzard, Coyote, No Name, Johnson, Pyeatt, Grouse, Sage, <br />Oak, Flume and Deacon. These drainages flow primarily in response to snowmelt and/or heavy <br />rains. All of these drainages eventually discharge into the Yampa River. Drainages in the <br />southern portion of the permit area drain southward to the Williams Fork River. These drainages <br />include the upper portions of Ute, Castor, Deer, Elk, Horse Gulches, Deal and Jeffway Gulch. <br />Natural surface waters are of a calcium-magnesium-sulfate type with total dissolved solids <br />content commonly greater than 1000 mg/l in the smaller streams and less than 1000 mg/l in the <br />largest streams. Total dissolved solids concentrations commonly peak during periods of low <br />stream flows; during high flows, waters are diluted resulting in low concentrations. <br /> <br />Ground Water Hydrology <br /> <br />Within the general area of the Trapper Mine, ground water exists in both bedrock and alluvial <br />aquifers. Significant bedrock aquifers are the Trout Creek, Middle, Twentymile, and White <br />sandstones. The Middle, Twentymile and White sandstones lie within the Williams Fork <br />Formation; the Trout Creek sandstone is the uppermost member of the underlying Iles <br />Formation. The major alluvial aquifers in the area are associated with the Yampa and Williams <br />Fork Rivers. Many of the coal seams, discontinuous sandstones, siltstones and some of the <br />smaller alluvial bodies in the area of the mine are also water bearing. These, however, <br />characteristically contain insufficient quantities of water to be considered significant aquifers. <br />Of the bedrock aquifers, the Twentymile sandstone contains the best quality ground water, a <br />bicarbonate-type water with a relatively low total dissolved solid content of less than 600 mg/l. <br />Ground water in the White sandstones contains total dissolved solids generally greater than 600 <br />mg/l due to high levels of sulfate and bicarbonate. Ground water in the coal-seam aquifers and <br />interbedded sandstones and siltstones is commonly of poor quality with total dissolved solids <br />greater than 1000 mg/l due to high levels of bicarbonate and sodium. <br /> <br />Regional Climate <br /> <br />The region has a highland continental climate characterized by low precipitation, large <br />fluctuations in diurnal temperatures, low humidity, moderate wind, and high levels of insolation <br />(exposure to sunlight). The Craig area is in the rain/snow shadow of mountain ranges to the west <br />and south and consequently has a high number of dry, clear days. <br /> <br />Local Climate <br /> <br />The climate of the Craig, Colorado area is characteristic of semi-arid steppe regions. The <br />average annual precipitation for the town of Craig, 5 miles north of Trapper, is 13.5 inches, of <br />which over one third is snowfall (averaging 66.5 inches/year). Trapper Mine's average annual <br />° <br />precipitation is 16.7 inches. The mean annual temperature in Craig is 43F, with recorded <br /> <br /> <br />15 <br /> <br />Trapper MineJuly 9, 2013 <br /> <br />