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-24- Some of these springs appear to be associated with local faulting and fracturing. Others appear associated with landslides or slumps. Most springs are noted to come from lenticular sands, and the recharge and discharge areas of these springs are concluded to be in close proximity because of highly seasonal variations in flow. However, it is likely that some of the more prominent and perennial springs receive their recharge, at least in part, from greater distances and from more continuous aquifer systems which have greater storage capacities. A number of springs have been adjudicated, apparently for irrigation and mine usage downstream. Water rights associated with those springs are discussed with the review of surface water rights. Numerous parameters in the natural ground water exceed recommended limits set for drinking water by the Colorado Department of Health including iron, ammonia, boron, zinc, lead, manganese, copper, fluoride, alkalinity, and sulfates. The climate of the region is typical of the Rocky Mountain area. The valley in which Paonia and Somerset are situated is semi-arid with annual precipitation averaging about 15 inches per year. Mean annual precipitation increases with elevation, reaching approximately 40 inches per year on the sumrnit of Mt. Gunnison. The May-September precipitation is 5 inches for the lowlands and 13 inches for the mountain peaks. This indicates that snowfall patterns play an important part in determining the hydrology of the area. Temperature extremes at Paonia have ranged from -28°F in January to 100°F during July and August. The average annual temperature is approximately 49°F. Snow fall averages 58 inches per year. The North Fork of the Gunnison River is the major drainage for the mine site. Streams on the northern portion of the permit area drain directly into the North Fork near Somerset. Minnesota Creek drains the remaining areas to the south which are outside the five year permit boundary. It enters the North Fork near Paonia. The North Fork has an annual streamflow at Somerset of approximately 313,200 acre feet per year (1933-1982). The flow is regulated by the Paonia Reservoir 5 miles upstream, which became operational in 1962. Flows during that period have ranged from a high of 451,300 acre-feet per year in Water Year 1962 to a low of 82,210 acre-feet in Water Year 1917. Water quality parameters for the North Fork are given in Table 3. As indicated, waters in the North Fork are a calcium bicarbonate type. There are moderate levels of sulfate. Salinity averages less than 100 mg/l. Water quality data has been collected at several sites throughout the environmental study area. The data indicate that those waters are also the calcium bicarbonate type and relatively low total dissolved solids concentrations.