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mining disturbances are expected but are projected to be within acceptable dischazge levels and will be mitigated by dilution. Regular monitoring of these flow rates and water quality will give adequate control of this current water source to protect water quality in Calamity Draw. The discharges from the mine enter Calamity Draw at a point about 2.5 [Hiles above the confluence of Calamity Draw and the San Miguel River. The above-mentioned parks consist of recent undifferentiated aeolian silts and sands overlaying the Dakota and Burro Canyon Formations. The perennial flow nature of both Tuttle and Calamity Draws is largely 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 aze 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. Grouud 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 azea. Near surface ground water in the Nucla area 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 Formatiori water is widely used for stock and domestic wells. Very little hydrologic documentation is available regazding the alluvium found along the small tributazies draining the azea. Peabody drilled one well in the alluvium of Calamity Draw in mid-1986. The well appeazs 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 primazily derived from irrigation return flow and secondarily from flow in Calamity Draw. Transmissivity varies from 6.6 to 10.1 ft2/day. The hydraulic conductivity varies from 0.4 to 0.6 fUday. The water is characterized as a saline, hard, 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 towazd 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 rechazged 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