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<br />' withdrawal rate of 598 acre-feet per year at full production. Clean coal production during this <br />reporting period was 1,491,591 tons compared to projected full production of 1.3 million tons per <br />year. <br />1 The estimated quantity of mine water discharged averages 0.15 cubic feet per second (CFS). The <br />average flow rate of the White River is 672 CFS resulting in a dilution ratio of over 4000 to 1. The <br />discharged water has been within effluent limits except for one exceedance of total iron and two <br />t exceedances of oil and grease. <br />The decline in piezometric levels in bedrock zones 'upper sandstone facies', 'siltstone/coal facies', <br />and 'lower sandstone facies' was anticipated as probable impacts as the result of underground <br />mining activities. As projected these impacts are localized and will most probably continue in the <br />' proximity of the mined area. <br />As projected, subsidence in Red Wash initially resulted in water ponding in the stream bottom. The <br />high content of silt and clay carried by Red Wash rapidly fills the ponds. The silt and clay layers <br />have sealed any cracks that formed in the alluvium as the result of subsidence. Water continues <br />' to flow in the surface channel at Red Wash while piezometric levels in the basal alluvial gravel have <br />dropped indicating that the basal alluvium is not recharged by surface flow infiltration. <br />3.3 Slgnltlcance of Impacts to Use of Water <br />The current rate of withdrawal of water from the lagoon in the White River alluvium is far below that <br />projected at full production. Based on the current level of production and the current rate of <br />withdrawal, Western Fuels is not likely to exceed the projected withdrawal rates even at higher <br />' production levels. <br />During this reporting period, lowering of the piezomefric level in the "upper sandstone facies' (at <br />' TW2-7U, 36-2U and 2-17U), the 'middle siltstone/coal facies' (at 2-7M, 35-4M and TW2-17M) <br />and the 'lower sandstone facies' (at 2-17L, TW2-7L, 2-7L, 36-2L, and 35-4L) was noted. The <br />significance of these impacts are minimal as no beneficial use of the bedrock ground water exists <br />in the Deserado Mine area. <br />' Water ponding in Red Wash as the result of subsidence over longwall panels No. 1, No. 2, No. 3, <br />No. 4, No. 5 and No. 6 acted as stilling basins for deposition of clays and silts being carried down <br />' Red Wash. The significance of this impact is beneficial as the sediment load to the White River was <br />reduced. The same impact is expected as a result of subsidence over subsequent longwall panels. <br />1 <br />19 <br /> <br />