nickel, WET55 was one of only five sites with a reportable water 

 column concentration. 



Chemical history. A single specific conductance measurement 

 collected in August 1990 from an uncertain point on North Widgeon 

 Slough is the only other chemical information known for this site. 

 The value reported (1510 microsiemens/cm) was almost an order of 

 magnitude lower than at the time of the DHES sampling. The history 

 of North Widgeon Slough probably includes complete desiccation 

 during times of prolonged drought. 



Sediments. Relatively high concentrations of extractable calcium 

 and magnesium may reflect deposition of authigenic carbonate 

 minerals in North Widgeon Slough sediments. Extractable 

 concentrations of arsenic, boron and copper were at or near the 

 upper end of the ranges shown for this site class. Iron, nickel, 

 vanadium and zinc ranked mid-range in comparison to other sites in 

 this class. The concentrations of most other trace elements 

 analyzed were below reporting limits. The extractable boron 

 concentration reported exceeded the mean concentration for soils 

 of the western United States by a factor of 4.6; arsenic exceeded 

 the western U.S. soil mean by a factor of 1.25. Other trace 

 element concentrations were equal to or lower than regional mean 

 soil values. 



