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o N I--'- CO . . The mean salinity is 18 648 mg/L for Glenwood Springs water and 9295 mg/L for Dotsero Springs water. Quality analyses for both areas indicate that saline springs waters are domi-nated by sodium and chloride (90 percent of TDS) and contain large concentrations of calcium and sulfate. The source of these ions is dissolution of halite and gypsum/anhydrite beds in the Eagle VaHey Evaporite by circulating meteoric water. The elevated temperatures of the Glenwood, 41. 7 C, and Dotsero, 29.5 C, springs waters may result from deep circulation through a normal geothermal gradient or from the presence of an el- evated geothermal gradient, as evidenced by recent volcanic activity and other thermal springs and weHs in the study area. Springs and flowing weHs in outcropping portions of Leadville Limestone indicate that recharge takes place away from these outcrops and in elevated interior portions of the study area. The very similar ionic .contents of Glenwood and Dotsero spring waters require either common recharge areas or different recharge areas with the same lithoiogic characteristics. Probable areas of recharge are in the northeastern and southern portions of the study area. These areas possess structural, topo- graphic, and lithologic attributes that may explain the physical and chemical properties of the Glenwood and Dotsero springs. Recharge probably infiltrates downward along deep faults or volcanic necks. Downward migrating water contacts halite and gypsum deposits of the Eagle VaHey Evaporite, acquiring high ings waters may result from deep circulation through a normal geothermal gradient or from the presence of an elevated geothermal gradient, as evidenced by recent volcanic activity and other thermal springs and weHs in the study area. The combined flow rate of the 14 identified springs was 0.296 m3/s (10.46 ft3/s1. The char- acteristics of these springs included: Temperature range. 25 to 51 oC (77to 124 oF). pH: 6.6 to 7.6. TDS: 18 780 mg/L Cations: Sodium, 90%; Calcium, 7%; Potassium, 2% Anions: Chloride, 83.9 Sulfate; 10.2%; Bica rbonate, 6.0%. Because of the high bicarbonate content of GS water, calcium could be reduced from 470 to 238 mg/L by neutralization with lime (calcium hydroxide) to precipitate calcium carbonate. The trace metals and trace anions were less than 0.1 mg/L. The raw water exceeded or approached the limits of toxicity for drinking water for cadmium, chromium. fluoride, and selenium. However, chemical pretreatment and desalting necessary to bring water to below TDS limits would reduce cadmium. chromium. fluoride, and selenium below limits. The salt load for the 14 Glenwood springs was 174,700 metric tonnes (192,570 tons) annu- ally. !t was estimated in the PIQR that the identified springs accounted for only 50 percent of the salt load produced by the Dotsero and Glenwood Springs. A-7 ,