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The expected ground water impacts for the Meadows No. 1 Mine are largely negligible. Mining at the Meadows No. 1 Mine did not disrupt any local aquifers. Little or no ground water of a regional nature has been detected at the Meadows No. 1 Mine. The nearest regional aquifer is the overlying Trout Creek Sandstone. No water was encountered in the coal seam or any of the overburden strata which were disturbed during mining. The operation will not affect any of the major regional bedrock aquifers, therefore the probability of causing degradation of water quality in these aquifers (Trout Creek Sandstone, Twentymile Sandstone) is small. The area which has been mined lies stratigraphically below the Trout Creek Sandstone aquifer (see figure 3). The dip of the underlying bedrock strata is toward the west. The nearest mine, Seneca II, lies six miles to the south, southwest. Therefore contributions to cumulative groundwater affects by Meadows No. 1 Mine are negligible as well. A spoils aquifer could potentially develop in the area of the backfilled pit. Prior to mining, the Pinnacle Coal seam received no groundwater recharge due to an impervious shale above the seam. Breaking, removal, and mixing of the shale during mining and reclamation processes have resulted in the shale layer no longer restricting recharge of the coal seam. However standard percolation tests demonstrated that infiltration and percolation rates through the backfill are so low that recharge is not expected. Therefore the potential for groundwater degradation is remote. Surface Water The Yampa River is the major perennial stream in the area. Its headwaters lie in the mountainous areas to the north, east and south of the study area. Flow in the Yampa River is dominated by snowmelt runoff with more than half the annual flow occurring in April, May and June. The U.S. Geological Survey maintains a gaging station on the Yampa River near Hayden, Colorado. Data on the quantity of stream flow at this station are published annually in the U.S. Geological Survey 's Water Resources Data for Colorado. Three small ephemeral drainages collect water discharged from sediment ponds in the backfilled pit area and from the haul road. Approximately 90 percent of runoff from the pit flows into the Grassy Creek drainage. The remainder of pit runoff and drainage from the haul road flow into Stone House Gulch and Goal View Gulch. These three drainages empty into the Yampa River. The loadout and office/shop facilities are located directly adjacent to the Yampa River. Runoff from these areas is currently controlled by sediment ponds, and gravel and berms. Applicable NPDES effluent limitations are in effect for al l disc harges. Expected surface water affects include increased evaporation losses from sediment ponds, which are assumed to be offset by increased runoff from impervious areas such as haulroads and structures, and increased total dissolved solids and total salt loads in receiving streams. The affect of surface water runoff from the Meadows No. 1 Mine on water quality in the Yampa River is negligible due to the small quantity and good quality, since no water is discharged unless it meets NPDES effluent limitations. Therefore affected water quality in the Yampa River would remain suitable for both flood irrigation and domestic use. -B-