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 9.2 SaskPower 



Ambient SOj monitoring conducted at SaskPower's station which is located 8.0 kilometres 

 southeast of the plant, near the 49th parallel, showed no violation for 1991 , the same as 

 in 1990. The highest hourly reading of 0.081 ppm occurred on October 17, 1991 at 4:00 

 hours. Weather data recorded by Environment Canada's weather station located at 

 Rockglen (37 kilometres northwest of the plant) indicated winds blowing from the plant 

 towards the monitor at the time. This reading compares to the highest hourly reading of 

 0.049 ppm recorded in 1990. Downtime for the monitor was 5.6%, as compared to the 

 1990"s 1.3%. 



Suspended particulate concentrations at SaskPower's monitoring station exceeded 

 Saskatchewan Environment and Public Safety's 24-hour standard on two occasions in 

 1991, compared to five in 1990. The highest recorded value of 173.8 |ig/m^/24 hours 

 occurred on September 3. This, as well as the other violation, were probably caused by 

 field-blown dust as no specific episodes of heavy particulate release from the plant stack 

 on violation days could be determined. The annual geometric mean of 26.8 ^ig/m^ is well 

 below the provincial standard of 70.0 and compares with the 1990 mean of 35.4. 

 Downtime for the sampler was 6.7%, as compared to 1 990's 1 .7%. 



