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Draw. Annand Draw is intermittent. <br />combination of parallel and dendritic. <br />mi/mi'), channel sinuosities are low <br />steep (.039 to .218 ft/ft). <br />Ground Water <br />The drainage patterns exhibited in these draws are a <br />The drainages densities are moderate (7.26 to 10.38 <br />1.01 to 1.07 mi/mi), and channel gradients are moderate to <br />Aquifers of particular interest in the permit area include the coals and interbedded units of the <br />Williams Fork Formation Middle Coal Group as well as the overlying Twentymile Sandstone <br />and the underlying Trout Creek Sandstone. Recharge to the bedrock aquifers occurs as <br />infiltration at the outcrops, which are parallel to the axis of the Fish Creek Anticline. Discharge <br />is through bedrock springs which are tributary to Sage Creek, and one in the upper reach of <br />Annand Draw. Bedrock groundwater is confined except in outcrop areas. <br />Baseline studies showed that the Lennox Overburden and Coal units are artesian flowing <br />aquifers. The Wadge Overburden occurs under confined and unconfined conditions. The <br />unconfined conditions are encountered near the outcrops. The saturated aquifer thickness of <br />these units range between 4 and 200 feet. <br />The Wadge Coal aquifers appear to be largely confined, whereas the Wadge Underburden <br />aquifer occurs under both confined and unconfined conditions. The Wolf Creek Coal occurs <br />under confined conditions; however, the Wolf Creek Underburden is both unsaturated and <br />unconfined. <br />Movement of groundwater in bedrock aquifers is controlled by structural folding and faulting <br />and stratigraphy. Confined conditions occur at synclinal axes, and unconfined conditions occur <br />near the outcrops. No significant faulting is known to occur within the permit area. <br />Two recharge boundaries are known to exist in the permit area. An erosional face along the <br />northerly -plunging axis of the Fish Creek Anticline provides a localized recharge boundary for <br />the Wadge Coal and Wadge Overburden. Additionally, the Wolf Creek Coal outcrop, parallel to <br />the axis of the Dish Creek Anticline, is a recharge boundary for the Wolf Creek Coal. <br />In general, the Williams Fork Formation, which includes the Twentymile Sandstone and the <br />Middle Coal Group, has yields of up to 100 gpm. The average yield is approximately 10 gpm. <br />The underlying Trout Creek Sandstone has a yield of approximately 5 gpm and occurs under <br />confined conditions with artesian head of 30 feet above the ground surface. <br />Alluvial aquifers in the permit area include the Sage Creek alluvium, Annand Draw alluvium and <br />Grassy Creek alluvium. The Sage Creek alluvium has a saturated thickness of between 7.5 and <br />56 feet. Annand Draw alluvium and Grassy Creek alluvium have a saturated thickness of 12 and <br />11-28 feet, respectively. Groundwater occurs under unconfined conditions in the alluvial <br />aquifers. <br />Movement of groundwater in the alluvial aquifers is controlled by the characteristics of the <br />stream drainages within which they occur, including the stream gradient as well as the width, <br />VA <br />