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A review of the data from the triplicate sample splits shows the 

 United States and Canadian results to be similar for most of the 

 water quality variables. Results reported by the participating 

 laboratories are subject to variability owing to differing analytical 

 techniques. Following are areas where discrepancies were present: 



specific conductance Environment Canada measurements (laboratory 

 and field) were about 5 percent higher than 

 the mean for all laboratories 



phosphorous (ortho) 



chloride 



SiO' 



TDS 



metals 



boron 



Apparent disagreement between U.S. Geological 

 Survey and Saskatchewan results 



Saskatchewan Provincial Health Laboratory 

 concentrations higher than other laboratories 



Saskatchewan Research Council reports silica 

 results as Si while other labs report silica 

 as Si02 



Environment Canada and U.S. Geological Survey 

 results differ by about two percent. Sas- 

 katchewan Research Council results non- 

 comparable (analyses done gravimetrically) 



Substantial differences between Saskatchewan 

 Research Council and other participating lab- 

 oratories for nickel, copper, vanadium 



Results generally comparable; Environment 

 Canada and U.S. Geological Survey results 

 differ by about 8 percent 



Table 5 lists the analytical results of the above measurements made 

 by the laboratories. 



The results of analyses of the United States standard reference 

 sample (Table 6) showed good agreement between laboratories for most 

 variables. The Saskatchewan Research Council results for sulphate, 

 chloride, and TDS varied from those reported by the other labora- 

 tories. Boron results from Environment Canada were not reported due 

 to interference. Environment Canada pH (laboratory) was signifi- 

 cantly above the multi-laboratory mean. 



