15 



Resources Observation System (EROS) and Earth Resources Technological 

 Satellite (ERTS) to delineate the scope of the problem (11) (19). Even 

 with a more definitive figure of total acreage destroyed, however, the 

 impact on production of agricultural commodities and the loss in terms 

 of market value will still be difficult, if not impossible, to ascertain. 



Saline seep is certainly responsible in part for increasing 

 saline pollution of Montana's water (28). The growing unpalatability 

 of community water supplies at Nashua, Wiota, and Frazer has been 

 attributed to saline seep (23), and nitrate poisoning of livestock from 

 salinized farm reservoirs has recently been reported in the Fort Benton 

 and Denton areas (3). Seeps develop in areas having no alternate source 

 of fresh water for household, livestock, or wildlife purposes (15). 

 Siltation from erosion, probably the most important water quality problem 

 in dryland streams, is likely to increase with loss of vegetative cover 

 brought on by the seeps (17). 



Representative analyses of water and salt samples from the 

 Highwood Bench and Missouri River, along with recommended standards 

 for domestic water supplies, are shown in Table 1. 



In all surface water, groundwater, and salt sannples collected 

 on the Highwood Bench, the predonninant dissolved constituents are 

 sodium, magnesium, sulfate, and nitrate. The samples also contain 

 unusually high concentrations of trace elements: aluminim, iron. 



