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-21- 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, perhaps extending into the Minnesota Creek drainage. 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. Ten monitor wells are sampled on the five year permit area. Nineteen wells are monitored within the entire life of mine area. Total dissolved solids (TDS) in all wells sampled ranged from 252 mg/1 to over 6,000 mg/1. In the Barren Member, TDS ranges from 252 mg/1 to 1,215 mg/1, with high seasonal variations. In the F-Seam, TDS ranges from 900 to 1,700 mg/1, with much less notable seasonal variations. Total dissolved solids concentrations observed in the spring sampling ranged up to 2,100 mg/1, however, averages were 400-600 mg/1 for most springs. Water quality data from the springs are presented on Table 2.8.1.R. and in WECC's quarterly hydrologic data. Numerous parameters in the natural ground water exceed recommended limits set for drinking water by the Colorado Department of Health. Those in excess include iron, a~nnonia, boron, zinc, lead, manganese, copper, fluoride, alkalinity, and sulfates. The Mt. Gunnison Mine No. 1 life of mine area consists of 14,341 acres located approximately 10 miles east of Paonia, Colorado. The mine area lies within the drainage of the North Fork of the Gunnison River which is tributary to the Colorado River system. The area is mountainous with elevations ranging between 6,000 feet at Somerset and 12,719 feet at Mt. Gunnison. 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 summit 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 -28oF in January to 100°F during July and August. The average annual temperature is approximately 49oF. 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.