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the predominant drainage characteristics reconstructed. Thirteen of the seventeen drainageways <br />anticipated to be disturbed and /or reconstructed in this permit term drain a watershed of less than one <br />square mile above the uppermost sediment control pond in the drainage. All of the drainages impacted <br />by mining in this permit term are ephemeral. The eleven smaller watersheds are drained by West Pyeatt <br />(256 acres), Middle Pyeatt (411 acres), Grouse (177 acres), Sage (125 acres), Oak (313 acres), Ute (81 <br />acres), Deer (32 acres), West Flume (139 acres), Middle Flume (578 acres), East Middle Flume (133 <br />acres), East Flume (93 acres), Horse (285 acres), West Horse (248 acres) and Deal (176 acres). The <br />other watersheds are No Name (1,379 acres), Johnson (1,359 acres), and East Pyeatt (1,157 acres). <br />As is evident upon examination of the postmining profiles, mining and regrading operations , or have <br />caused them in most areas to be elevated as a result of overburden and interburden swell not completely <br />offset by the amount of coal recovered. The differences are caused by drainage geometry and waste to <br />coal ratios. An exception is the K pit area where some material will be removed by a truck/excavator fleet <br />and placed in a permanent fill location. In general terms, the ephemeral drainageways will be re- <br />established to functionally blend with the undisturbed drainageway below the area to be backfilled and <br />reclaimed. <br />The reestablished drainageways will have slopes that generally diminish in magnitude from the top to the <br />bottom approximating a parabolic curve. Also, the principal channel of a drainage will be constructed <br />such that the approximate drainage area which existed prior to mining for a particular drainage basin and <br />its associated principal channel will be established for the postmine drainage <br />3-43 <br />— 'Rlo0 <br />6 / C&IZD16 <br />