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precipitation and surface runoff, from up gradient in the Williams Fork formation, and from downgradient in the Williams Fork and Wadge coal. Until an equilibrium is established between the bacltfilled pits and the surrounding aquifers, a diminution of water quantity may be expected at some springs (S-1, S-5, 5-23, 5-41) and at Temple Well No. 1. Eventually, springs and seeps will emanate from the topographically lowest points of the reclaimed pits. These waters will be characterized by high levels of iron, manganese, total dissolved solids, and possibly boron. Unless this water is intercepted by holding ponds, it will add flow to the unnamed drainage directly below the mining area and eventually to Hubberson Gulch and Dry Creek. This flow may be expressed as surface flow, or as an increased (elevated) water table, dependent upon local conditions. It is projected that the concentrations of these parameters will decrease with time as the readily dissolvable elements are leached until an equilibrium level is reached. Further discussion of this is found under the Surface Water Effects of the Probable Hydrologic Consequences section. Ground Water Effects (South Extension Area Addendum) Probable hydrologic consequences to the ground water regime as a result of mining the Wadge, Sage Creek and Wolf Creek coal seams within the south extension area have been assessed. Localized effects to the hydrologic system will include: 1) The drawdown of ground water, due to pit dewatering. For the Wadge ground water system, the largest estimated radial distance will occur in the overburden aquifer, where cone-foot drawdown is predicted to occur approximately 151 feet from the mined area after one year of pit inflow and approximately 285 feet from the area after four years of inflow. For the Sage Creek/Wolf Creek systems, the estimated drawdown in the overburden is predicted to occur approximately 333 feet from the mined area after one year of pit inflow and approximately 1,441 feet from the area in year 2011. No pre-existing water sources with registered water rights including water wells were identified in the south extension area. The maximum radius of influence for one foot of drawdown over the predicted life of mine for the south extension area will not extend beyond the permit area boundary. Because drawdown will be limited to areas within the permit boundary, there is no anticipated impact to adjacent water users due to drawdown. 2) The establishment of a relatively unconfined aquifer of poor quality in the backfilled pits. Spoil discharge may increase the TDS of the overburden ground water system by as much as 261 % (Wolf Creek Seneca II-W Findings Document 42 November 17, 2004 Perini[ Revision No. 4