2.3 Review of Water-Quality Objectives 



The International Joint Commission in its Report to Governments, titled " Water-Quality in the Poplar 

 River Basin", recommended that the Committee "periodically review the water-quality objectives within 

 the overall Basin context and recommend new and revised objectives as appropriate", hi 1991, the 

 Committee undertook a review of water-quality objectives. 



The Committee approved changes in water-quality objectives recommended by the 1991 subcommittee 

 which was formed to review the objectives. Revised objectives approved by the Committee are listed in 

 Table 2.1. 



The Committee discussed the water-quality objectives for 5-year and 3-month flow-weighted 

 concentrations for total dissolved solids and boron. Although the Committee agreed that calculation 

 procedures to determine flow-weighted concentrations are time consuming and probably scientifically 

 questionable, no consensus was reached on alternative objectives or procedures. Some of the 

 discussions and decisions that were made at this meeting include: Suspending most of the parameters 

 that were recommended for discontinuance in 1991 such as dissolved aluminum, bacteria, pH, mercury 

 in fish, and im-ionized ammonia. Canada has expressed concern about the need for the flow-weighted 

 boron and TDS objectives given the uncertainty of the scientific validity of how the objectives are 

 calculated. 



According to the IJC report titled, "Water-Quality in the Poplar River Basin", the Committee can 

 "recommend new and revised objectives as appropriate". After a lengthy discussion, members agreed 

 not to remove any objectives at this time. Instead, the Committee decided to suspend the monitoring 

 and reporting of several parameters after reviewing the water-quality objectives. The suspended 

 parameters are: dissolved aluminum, un-ionized ammonia, total chromium, dissolved copper, mercury in 

 fish, fecal coliform, and total coliform. The decision to suspend these parameters was based on data 

 indicating concentrations or levels well below or within the objectives. In addition, the Committee 

 agreed there was a need to review the flow-weighted objectives for boron and TDS. The Committee 

 also agreed to other minor revisions to the water-quality objectives for clarification. For example, 

 changing the designation for pH fi-om "natural" to "ambient". 



