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Water quality in Sage Creek varies from upstream to downstream. Upstream from the permit area, a CaMgHCCO~ water type predominates. Total dissolved solids (TDS) typically range from 296 to 510 mg/1 at high and low flows, respectively. Downstream from the permit area, a CaMgSOaHCO3 water type predominates, and TDS typically ranges from 526 to 695 mg/I at high and low flows, respectively. Most of the flow in Sage Creek is diverted out of the stream for irrigation purposes prior to reaching the site where downstream baseline data was collected. Sage Creek water is also used for livestock watering. Grassy Creek Grassy Creek is a perrenial stream to the east of the permit area. Flow in Grassy Creek upstream from the permit azea was perennial during baseline data collection. Mean flow rates in the spring, summer and fall were 0.91, 0.10, and 0.06 cfs respectively. A CaMgSOaHCO3 water type predominates upstream from the permit area. TDS ranges from 680 to 853 mg/I at high and low flows, respectively. Permit Area Intermittent flows from the northern side of the permit area drain through Annand Draw into Scotchmans Gulch, and then into Grassy Creek. Spring flows in Annand Draw aze predominately from the melting of snowpack. Late spring to early summer flows are a combination of bank storage, runoff from precipitation events over saturated or frozen ground, or perched spring flow recharged by snowmelt. The remainder of the year, the channel exhibits ephemeral flow characteristics. The mean flow rate in the spring is .056 cfs, and .02 cfs in the summer. Within the permit area, there are five primary drainages, four of which are ephemeral. The drainage channels have been identified as Annand Draw, 011 Draw, Y1 Draw, Y2 Draw, and Y3 Draw. Annand Draw is intermittent. The drainage patterns exhibited in these draws are a combination of parallel and dendritic. The drainage densities are moderate (7.26 to 10.38 mi/mi~), channel sinuosities are low (1.01 to 1.07 mi/mi), and channel gradients are moderate to steep (.039 to .218 ft/ft). Ground Water Aquifers of particular interest in the proposed permit area include the coals and interbedded units of the Williams Fork Formation Middle Coal Group as well as the overlying Twentymile Sandstone and the underlying Trout Creek Sandstone. Recharge to the bedrock aquifers occurs as infiltration at the outcrops which are parallel to the axis of the Fish Creek Anticline. Discharge is through bedrock springs which are tributary to Sage Creek and one in the upper reach of Annand Draw. Bedrock groundwater is confined except in outcrop areas. Baseline studies showed that the Lennox Overburden and Coal units are artesian flowing aquifers. The Wadge Overburden occurs under confined and unconfined conditions. The unconfined Yout Mine 1 1 Much 6.2001