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channels have been aligned to more or less follow the premining drainages, and to <br />deliver surface runoff near the locations where premining streams previously emptied. <br />Please refer to Exhibit 1, Phase III Bond Release for the location of these facilities in <br />relation to the reclaimed lands that are the subject of this application. <br />Ground water resources within the mining zone in the area for which bond release is <br />sought were described in the permit application as being insignificant, limited to <br />sporadic seeps from hillsides with flow quantities too small to measure. Such seeps <br />were likely the seasonal surface expression of isolated perched water tables, most likely <br />associated with the several coal seams in the East Pit and West Pit mine areas. These <br />perched zones were not judged to be recharged from the higher zones of the watershed <br />to the south. The presence of the West Fork of Good Spring Creek effectively cuts the <br />mine permit area off from the larger recharge areas to the west and south in the <br />Danforth Hills. The base elevation of the lowermost coal seam being mined is several <br />hundred feet above the deeply incised surrounding valley floors. Further, the coal <br />seams being mined in the Williams Fork Formation are separated from the underlying <br />Trout Creek Sandstone by a more or less impermeable zone at the base of the Williams <br />Fork which serves as an effective aquiclude. All of these factors result in there being <br />only minor and discontinuous perched groundwater in the mining area, thereby <br />removing the necessity of monitoring groundwater on this ridge top, as stated in Section <br />4.05.12 of the original permit application. These factors also limit the ground water <br />recharge areas to essentially the fraction of precipitation falling on the permit area that <br />is not immediately lost to evapo-transpiration. That fraction has been estimated <br />previously to be on the order of 0.35 inches/year, about 1.5% of incipient precipitation. <br />The current reclaimed condition of the mined lands that are the subject of this <br />application and the presence of the permanent ditches assures that there will be no <br />significant impact on the surface or groundwater balance. <br />4.1 Permanent Hydrologic Features <br />Certain permanent hydrologic features including diversion ditches and stock ponds will <br />remain in place and in service after bond is released as provided in Section 4.05.17. <br />In the East Pit, the Streeter Ditch, Gulch A Ditch, and Section 11 Ditch will convey runoff <br />originating on the reclaimed lands easterly toward the Good Spring Creek drainage. <br />Currently these ditches report through two sedimentation ponds, Streeter Pond and <br />Gulch A pond, before their flows are released into Good Spring Creek. All of these <br />ditches have been designed to safely convey the 100-yr, 24-hr storm runoff in <br />accordance with Section 4.05.4 or the 10-yr, 24-hr storm runoff in accordance with <br />Section 4.05.3, as applicable depending on tributary area, while maintaining the integrity <br />of the ditch lining. The waters from Section 11 Ditch are currently conveyed northward <br />to the Gulch A drainage via a contour ditch in Section 11. This contour ditch and the two <br />sediment ponds described above will be removed after bond release at such time as <br />sediment control release has been approved. <br />0 <br />Phase /// Bond Release Application 12