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of Quaternary age overlie the exposed geologic formations in some areas, particularly along <br />larger streams. <br />The permit area lies structurally between the parallel, south-southeast trending Sage Creek and <br />Fish Creek anticlines. The axis of the Sage Creek Anticline is situated about one to two miles <br />west of the western edge of the Yoast permit area. The axis of the Fish Creek Anticline <br />originates near Scotchman's Draw and extends south-southeasterly dividing the northern first <br />five-year mine block from the neck portion of the permit area. <br />The rock units in the permit area dip predominantly 15 to 20 percent to the north in the north <br />mine block, to the northwest in the neck area, and to the west in the south mine block. More <br />extreme dips of 25 to 35 percent occur locally in the northwest and northeast parts of the north <br />mine block. The rock units are apparently unaffected by "any significant faulting within the <br />permit area. <br />Surface Water <br />The Yoast Mine drains to Sage Creek on the west side, and to Grassy Creek on the east side. <br />Sage Creek and Grassy Creek are perennial tributaries to the Yampa River. Annand Draw and <br />Scotchmans Gulch are intermittent drainages which drain from the northern side of the permit <br />area into Grassy Creek. The Yampa River then flows to the Green River and eventually the <br />Colorado River. <br />Sage Creek <br />Sage Creek is a perennial stream to the west of the permit area. Flows upstream from the permit <br />area range from an average 0.7 cubic feet per second (cfs) in the spring to near 0 in late summer <br />and fall. Approximately two miles downstream from the permit area, average flows of 1.5, 0.09, <br />and 0.04 cfs were observed during baseline data collection in the spring, summer, and fall <br />respectively. <br />Water quality in Sage Creek varies from upstream to downstream. Baseline data indicate a <br />predominately CaMgHCC03 water type upstream from the permit area. Total dissolved solids <br />(TDS) typically ranged from 296 to 510 mg/l at high and low flows, respectively. A <br />CaMgSO4HCO3 water type predominated downstream from the permit area, and TDS typically <br />ranged from 526 to 695 mg/1 at high and low flows, respectively. <br />Most of the flow in Sage Creek is diverted out of the stream for irrigation purposes prior to <br />reaching the site where downstream baseline data was collected. Sage Creek water is also used <br />for livestock watering. <br />Grassy Creek <br />Grassy Creek is a perennial stream to the east of the permit area. Flow in Grassy Creek upstream <br />from the permit area was perennial during baseline data collection. Mean flow rates in the <br />spring, summer and fall were 0.91, 0.10, and 0.06 cfs respectively. A CaMgS04HCO3 water type <br />Yoast Mine 11 December 15, 2010