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<br />-22- <br />within the permit area, the coal-bearing Fruitland Formes tion dips below the <br />alluvial valley of Stollsteimer Creek. The alluvial ground water aquifer is <br />hydrologically connected to the bedrock aquifers and provides the primary <br />source of recharge water to these aquifers, The coal seams are saturated <br />below the level of Stollsteimer Creek and its associated alluvial valley <br />floor. <br />As the "B" and "C" seams were erposed in tae southern half of the e.isting <br />pit below the Ieve1 of the alluvial valley of Stollsteimer Creek, pit inflocrs <br />developed. One inflow was observed July 13, 1982 by MLRD staff. This inflow <br />[ras entering the southwest edge of the pit, <br />The applicant states that water which accumulates in the pit is pumped to the <br />adjacent sediment pond. Water is allowed to serttle in the pond until such time <br />that it meets the effluent discharge limitations set down by the Department <br />of Health, 1/ater is then pumped from the pond to Stollsteimer Creek. Sampling <br />occurs at the time of discharge to the creek, therefore the quality of Stollsteimer <br />Creek should not be diminished. Additionally, except for a small amount of <br />water that may be Lost due to evaporation, aII inflows are returned to the <br />surface water system. J <br />Following mining the pumping of pit water will cease. The pit inflows will continue <br />and will recharge the spoils. This recharge will produce a spoil [/ater aquifer. <br />The inflows [rill continue to deplete the water tributary to Stollsteimer Creek <br />until the spoil aquifer is fully recharged at [rhich time the rate of recharge to <br />the spoil aquifer will equal the rate of discharge. Given the present inflow <br />rates, t':e srroil aquifer will recharge wit.9in 20 to 30 years. :",he impacts to the <br />quantity of flow in Stollsteimer Creek wi21 deminish logar.ighmically with time <br />over a 30 year period from an initial rate of 10 to 200 opm. <br />The quality of inflow water and recharge water will become degraded while in <br />contact with the pit floor and fragmented rock strata making up the spoil. <br />The degree of water quality degradation will depend on the residence time of <br />water in the spoil aquifer. The residence time will be dependent on the <br />recharge and ultimately the discharge raters of the spoils aquifers. The spoil <br />aquifer[rhich develops in the existing pit will discharge from the southwest <br />corner of the presently active pit. The total estimated discharge of spoil <br />water from the existing pit is estimated to be Z gpm, She spoils in the area <br />of the Barren Ridge mining operation will also develop discharg::ng spoil aquifers. <br />The estimated discharge from the area is less than 1 gpm. <br />The discharge of spoil water will be to one or more of the following hydrologic <br />systems: the surface crater system, the alluvial ground water system of <br />Stollsteimer Creek (an AVF), and/or the rock strata of the Lower Fruitland <br />Formation, The water quality of the receiving hydrologic system will be <br />degraded by spoil water. The :rater quality change can rot be fully quantified <br />without knowing the resulting spoil water quality. The stiaulation in the sect on <br />titled "Hydrologic Balance: Ground [dater" [rill require the necessary quantitative <br />data needed to determine the impacts of mining on the quality of ground water. <br />