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The results were subsequently distributed to all participants for 

 review by both field and analytical personnel. The majority of param- 

 eters showed good reproducibility. The results for a number of trace 

 metals and some nutrients were more variable, with order of magnitude 

 differences existing between agencies in some cases. It is thought 

 that much of this variability relates to differences in analytical 

 technique (for example, atomic absorption versus inductively-coupled 

 argon plasma). These annual quality control exchanges will prove 

 very valuable to any future interpretive undertakings. 



Review of Flow-Weighted Objectives 



During 1988, Environment Canada funded a study to assess the appro- 

 priateness of using flow-weighted objectives for the East Poplar 

 River. The study also included the documentation of the current 

 flow-weighted algorithm, and an assessment of the suitability, sig- 

 nificance, and representivity of the method. 



The report titled, "Evaluation of the Transboundary TDS and Boron 

 Water Quality Objectives for the Poplar River" prepared by Hydro-Qual 

 Consultants, Inc. (October 1988) contained the following recommenda- 

 tions: 



1. Flow-weighting should be discontinued, as the relationship between 

 flow-weighted concentration and the toxic effects associated with 

 irrigation is weak. 



2. Since the likelihood of exceedance of the boron and TDS and boron 

 objectives now appears to be small, it was recommended that the 

 monitoring effort on the East Poplar River be reduced. 



