VI 



International Joint Commission. Continued investigations of U.S. 

 Geological Survey and Environment Canada quality assurance data have not 

 resolved incompatibility for certain parameters. Additional quality 

 assurance work has been recommended for 1986. 



The outer limit of the cone of depression from coal seam dewatering 

 remained about the same distance north of the International Boundary. 



The total estimated seepage from the ash lagoons and polishing ponds was 

 0.750 litre per second, well below the seepage limits proposed by the 

 International Poplar River Water Quality Board. The leachate front has 

 been calculated to have advanced 4.23 metres towards Cookson Reservoir 

 since the ponds were first filled. 



Plant stack emissions did not cause or contribute to violation of Montana, 

 United States, or Saskatchewan ambient air quality standards. 



