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_19_ The quantity of surface water will be impacted through evaporation of water in the pit, in sediment ponds and through diminished spring flows during mining. Following mining and reclamation, the surface water flow rate (quantity) will approach pre-mining conditions. The impacts to surface water quantity will be minor given the small drainage area involved, the minor spring flow contribution, and the requirement to discharge waters from the ponds. Ground water quantity will be impacted during mining through the mining of the recharge areas of aquifers and through depletions of ground water storage (lowering of existing ground water levels) in aquifers by mine induced pit inflows. Water which would ordinarily recharge the strata upgradient of the mine pit will be diverted into the pit during mining. The recharge area within the permit area is minor in comparision with respect to the entire recharge area of these aquifers up and down gradient of the mine. Ground water currently stored within the aquifers will be depleted by ground water flows from the aquifers into the pit (pit inflows) as the mining operation moves down the dip of the coals. The applicant predicts a maximum inflow rate of 200 gallons per minute which will lower water levels in the aquifers. Following mining the pumpage of pit waters will cease and a spoil aquifer will be established. This spoil aquifer will recharge the bedrock aquifers and ground water levels within the aquifers will approach pre-mining levels. The depletion of recharge will impact the quantity of discharges from springs and seeps down gradient of the mine, during and for a short period after mining. During mining, some of the ground water which is tributary to the springs and seeps will enter the pit, depleting spring and seep flows. Presently, springs and seeps from the aquifers in the permit and adjacent areas are primarily discharging to the stream in Carbon Junction Canyon. Thus, there will be a depletion of stream flows. However, pit inflow waters will be discharged to the surface stream, and the overall impact to the quantity of surface water during mining will be minimal. Following mining, ground water levels will return to pre-mining levels. This will result in the reestablishment of spring and seep flows consistent with pre-mine rates. The mining and processing of coal at the Carbon Junction Mine will impact the quality of both surface and ground waters during and after mining. Mining will disrupt the natural soils and rock strata in the disturbed areas of the mine operation. Disruption of soils and rock strata will increase the exposure of previously unexposed materials to both surface and ground waters. This exposure will result in increased leaching and weathering of these materials, with a corresponding increase in suspended solid and dissolved solid loads in surface waters and increased dissolved solid loads in ground waters. Suspended sediment levels will be minimized during mining by routing disturbed drainages through sediment ponds. Sediment ponds will remain in place until reclamation of the spoils and fill have been completed.