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transmissivity and storativity values associated with the local strata. Most of these <br />springs are used for stock watering. Mining should not prohibit this use, because <br />TDS levels will not surpass EPA limitations for stock watering purposes. Post <br />mining consequences of mining will be the development of spoils aquifers in the <br />backfilled pits. The reclaimed pits will have the highest permeability/porosity values <br />of any local aquifers. The backfilled pits will induce recharge from precipitation and <br />surface runoff, from up gradient in the Williams Fork formation, and from <br />downgradient in the Williams Fork and Wadge coal. Until an equilibrium is <br />established between the backfilled pits and the surrounding aquifers, a diminution <br />of water quantity may be expected at some springs (S-1, S-5, S-23, S~1) and at <br />Temple Well No. 1. <br />Eventually, springs and seeps will emanate from the topographically lowest points <br />of the reclaimed pits. These waters will be characterized by high levels of iron, <br />manganese, total dissolved solids, and possibly boron. Unless this water is <br />intercepted by holding ponds, it will add flow to the unnamed drainage directly <br />below the mining area and eventually to Hubberson Gulch and Dry Creek. This <br />flow may be expressed as surface Flow, or as an increased (elevated) water table. <br />dependent upon local conditions. It is projected that the concentrations of these <br />parameters will decrease with time as the readily dissolvable elements are leached <br />until an equilibrium level is reached. Further discussion of this is found under the <br />Surface Water Effects of the Probable Hydrologic Consequences section. <br />Surface Water Effects <br />The majority of runoff from disturbed areas during the mine life will be diverted to <br />Sediment Ponds 005 and 006, prior to release off site. Effluent from Ponds 005 and <br />006 flows to unnamed ephemeral gulches, and ultimately Dry Creek. Runoff from <br />the south extension area will flow into Hubberson Gulch, and ultimately Dry Creek. <br />Effects of mining on Dry Creek will involve changes in quantity and quality, which <br />are further described below. <br />A negligible acreage affected by the extreme eastern extension of the south area pits <br />and the neck pits between the north and south mining areas will drain to Sediment <br />Ponds 009 and 015, and eventually to Sage Creek. Measurable effects on Sage <br />Creek water quality or quantity are not projected, due to the small disturbance <br />acreage and the fact that there will be no spoil water flow to the Sage Creek <br />watershed. <br />The mining and reclamation activities will act to change stream channel <br />geomorphology. Drainage densities and channel frequencies will be reduced; <br />however, Seneca Coal Company has designed and located post-mining drainage <br />channels to minimize the erosive results of the lowered frequencies. <br />Seneca lI-W Findings Document 30 June I5, 2001 <br />Permit Renewal No. 3 <br />