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8.6.4 Waterfowl • The two existing cooling/retention ponds used during the experimental test mine phase would remain in place during the commercial mining phase. American Soda staff have observed use of either pond by waterfowl only once since their construction in the summer of 1997. The existing ponds would be used only under emergency or unusual circumstances if it were necessary to temporarily drain the well field piping. This use of the ponds would not pose any significant potential impacts to waterfowl. Two evaporation ponds are planned for the Yankee Gulch Project, one at the Piceance Site and one at the Parachute Site. Although waterfowl do not regularly use either the Piceance Site or the preferred Parachute Site because of the absence of suitable aquatic habitats, it is possible that waterfowl could make occasional opportunistic use of the proposed evaporation ponds, particularly if other bodies of water in the vicinity were frozen over during spring and fall migration periods. Although these ponds would offer no more than open-water resting places due to an absence of cover or aquatic forage, in doing so they may provide modest benefits to waterfowl. The Piceance Site evaporation pond will have an area of 14 acres and a capacity of approximately 85 acre-feet (Kvaerner 1998c). It will hold surface runoff from the Piceance Site processing facility area plus other liquid wastes from the processing facilities. Solutions will enter the Piceance Site evaporation pond at a maximum input temperature of 200°F (Kvaerner 1998f), from which they will cool down a rates that will depend on the ambient pond temperature and prevailing ambient weather conditions. It is possible that the hot water in the Piceance Site pond could have minor adverse impacts on visiting waterfowl. At the Piceance Site, water would comprise about 60 percent of the pond input, with silicate comprising about 22 percent, sodium carbonate about 15 percent, and sodium bicarbonate about 1 percent (Kvaerner 1998f). The liquid phase of the pond input would be an approximately 20 percent sodium carbonate solution. Solutions stored in the evaporation pond would be moderately alkaline with a pH of approximately 10 (Kvaerner 1998f). The actual potential effect on birds of the mineral-rich water in the Piceance Site evaporation pond is not known at this time. There is evidence that some wildlife seek natural mineral springs and licks where they ingest sodium and bicarbonate minerals that may replenish spent sodium reserves or alleviate acidic stomach conditions. Very high dissolved and suspended solids concentrations would only cause sickness if ingested in large quantities. The BLM has also suggested that contact with concentrated brine and subsequent crystallization of sodium bicarbonate on feathers could adversely affect the water Amencan Soda, L.L.P. 8_24 Commeraal Mine Plan August 18, 199N