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streams throughout the region with the majority of the water coming 

 during the low-flow season when it could rapidly impair the quality of 

 the entire stream. Because Montana is a headwater state for the Missouri 

 and Yellowstone River Basins, the potential widespread deterioration 

 of water quality is of national interest and concern. 



11. In all water and salt samples collected on the Highwood Bench 

 area, the predominant dissolved constituents were sodium (Na), 

 magnesium (Mg), sulfate (SO.) , and nitrate (NO_). The samples 

 analyzed so far also contain unusually high concentrations of trace 

 metals, namely aluminum, iron, manganese, strontium, lead, copper, 

 zinc, nickel, chromium, molybdenum, selenium, and vanadium. The 

 majority of these metals are rarely ever detected in water samples. 

 Groundwater samples commonly contain more than Z5, 000 milligrams 

 per liter (mg/1) total dissolved solids. High nutrient levels (nitrates 



and phosphates) have created eutrophic conditions in all the small ponds 

 and reservoirs in the area. Practically all the springs and reservoirs 

 on the Highwood Bench which were once fresh water are now highly 

 saline. This relatively rapid deterioration of all potable water supplies 

 in this area should serve as a warning to what may happen to the water- 

 resources of the entire region if the saline-seep problem is ignored. 



12. All available hydrogeological data indicate that the formation 

 and development of saline seeps are a result of local, not regional, flow 

 systems. 



