Chemical history. Sampling of the WET72 site was carried out in 

 conjunction with a synoptic sampling program on the Stillwater 

 River and it's tributaries which incorporated 16 surface water, 

 sediment and biological sampling stations both above and below the 

 WET72 site. For details, refer to work of the Montana Department 

 of State Lands, Hardrock Bureau of the Reclamation Division. 

 Additional environmental sampling near WET72 may have been 

 conducted by the Crown Butte Mining Company. 



Sediments. In contrast to the water column data, the sediments 

 from this site display a generally elevated distribution of trace 

 elements. Extractable concentrations of arsenic, boron, chromium, 

 copper, cobalt, iron, nickel, vanadium, and zinc all are near or 

 at the high end of ranges shown for Rocky Mountain sites and (in 

 most cases) for the entire data set. Most are exceeded only at 

 other sites of known contamination by mining or mineral processing 

 wastes. Extractable concentrations exceed the geometric means for 

 soils of the western United States by the following factors: 

 arsenic (4.1), boron (4.7) cobalt (2), nickel (2.7), selenium (1.7) 

 and zinc (2.8). For all but selenium, these factors exceed one 

 geometric deviation above the mean soil values. 



