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_18_ A number of springs have been adjudicated, apparently for irrigation and mine usage downstream. Water rights associated with those openings are discussed with the review of surface water rights. Nine monitor wells are sampled on the mine plan area. Total dissolved solids (TDS) in all wells sampled ranged from 252 mg/1 to over 6,000 mg/l. In the Barren Member, TDS ranges from 252 mg/1 to 1,215 mg/l, 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. 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, ammonia, 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 -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 within the permit boundaries. It enters the North Fork near Paonia. The North Fork has an annual streamflow at Somerset of approximately 313,500 acre feet per year (1962-1979). 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 82,270 acre-feet in Water Year 1977.