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Sask Power 



Sask Power began ambient air monitoring in 1981 near the East Poplar 

 River near the International Boundary to determine sulphur dioxide and 

 suspended particulate concentrations. There have been no recorded 

 violations of the provincial 24-hour ambient S0„ standard of 0.06 ppm, 

 over the last 10 years. The highest maximum hourly reading during this 

 period of 0.138 ppm occurred on January 7, 1989 at 0300 hours. Weather 

 data gathered for that day indicated northerly winds for that period of 

 time. As the air monitoring station is located south of the plant, the 

 plant is the most probable source. Down time for the monitor during the 

 past ten years has ranged from a low of less than 1% to a high of 31% , 

 for an average of 7%. 



Suspended particulate concentrations, including the average of 4 samplers 

 in use from 1981 to 1984 and 1 sampler from 1985 to present, indicate a 

 total of 87 violations of the provincial standard. The highest yearly 

 number of violations during the 10 year period totaled 34, in 1984. The 

 largest single concentration of 3,240 \iq also occurred during a severe 

 dust storm on May 10, 1989. The remaining violations could not be 

 attributed to the power plant operations. The 10 year average geometric 

 mean of 43.0 is well below the provincial standard of 70.0 ng/m 3 , with 

 the highest mean of 43.0 occurring in 1989. Annual down time for the 

 samplers over the 10 year period ranged from a low of 2% to a high of 

 36%, for a 9% average. 



During 1990, ambient SO- monitoring conducted at the Sask Power station 

 located near the International Boundary showed no violations, the same as 

 1989. The highest hourly reading of 0.049 ppm occurred on September 30, 



