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Draws is lazgely due to the local irrigation practices. Over the yeazs this more or less constant source of water in these drainage systems has encouraged the growth of vegetation. This has resulted in the channels becoming more erosionally stable but more incised. Surface water monitoring practices and frequencies are described the permit application. Also see Section B, Item II C, of this document for a summary of surface and ground water monitoring practices to which Western Fuels-Colorado has committed. Ground Water The New Horizon Mines lie in a ground water basin defined by the Nucla Syncline. This broad northwest trending syncline is recharged along the Uncompahgre uplift to the northeast and dischazges southwest towazd the major rivers flowing through the area. Neaz surface ground water in the Nucla azea is partially rechazged by irrigation return flow through Quaternary aeolian and alluvial deposits. The lower Dakota and underlying Morrison Formations aze regional aquifers, although water from the Dakota Formation is not heavily utilized due to its high salinity. The Morrison Formation water is widely used for stock and domestic wells. Very little hydrologic documentation is available regazding the alluvium found along the small tributaries draining the azea. Peabody drilled one well in the alluvium of Calamity Draw in mid-1986. The well appears to have been completed in a clay lens. The alluvial water table fluctuates seasonally within 5 to 10 feet of the surface with highest water levels in August and lowest water levels in January. Rechazge is primarily derived from imgation return flow and secondarily from flow in Calamity Draw. Transmissivity vanes from 6.6 to 10.1 ftZ/day. The hydraulic conductivity varies from 0.4 to 0.6 fUday. The water is chazacterized as a saline, hazd, neutral pH, calcium sulfate water with average TDS of 3291 mg/1. The aquifer overlying the coals in the upper strata of the Dakota Sandstone is unconfined and flows generally toward the southwest. Water levels fluctuate between 3 and 23 feet below the ground surface. Highest levels (closest to the surface) of this water table occur between June and August, as a result of irrigation, and lowest levels between December and Mazch. Two wells south of Calamity Draw (GW-N31 and GW-N32 on the monitoring stations map) have exhibited limited water level fluctuations since their construction in mid-1986. The Upper Dakota aquifer is predominantly recharged by return flow from the West Lateral Irrigation Ditch. Some rechazge is probably derived from infiltration of precipitation and subsurface ground water flow. The transmissivity of the overburden (Upper Dakota aquifer) varies from 3 to 53 ft2/day, averaging 13.3 ft2/day. The McWhorter analysis of pit inflow conservatively estimated that the hydraulic conductivity of the overburden was 0.61 fVday. Hydraulic conductivity calculations from field tests of the overburden showed a range of 0.39 to 1.05 ft/day, indicating moderate permeability. The water found in the overburden is chazacterized as very hard, saline, calcium/magnesium sulfate water with neutral pH. TDS levels vary from 1494-10074 mg/1 and average 4613 mg/1. Sulfate concentrations are very high, varying from 875 mg/1 to 6872 mg/1 and averaging 3176 mg/l. In some of the overburden wells, sulfate, TDS, manganese and fluoride exceed recommended standazds for 8