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1989 at 1200 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 recorded in 

 1989 of 0.138 ppm. Down time for the monitor was 1.3% , as compared to 

 1989's 3.2% . 



Suspended particulate concentrations at the monitoring station exceeded 

 Saskatchewan Environment and Public Safety's 24-hour standard on 5 

 occasions in 1990, the same as 1989. The highest recorded value of 1,409 

 M-g/m 3 /24 hrs occurred on October 26. This, as well as the other 

 violations were probably caused by field blown dusts, as no specific 

 episodes of heavy particulate release from the plant stack on violation 

 days could be determined. The annual geometric mean of 35.4 ng/m 3 is 

 well below the provincial standard of 70.0 and compares with the 1989 

 mean of 42.8. Down time for the sampler was 1.7% compared to 1989' s 

 4.5%. 



In-Stack Monitoring 



Sulphur dioxide averages in 1990 were higher than those in 1989. Daily 



concentrations ranged from a low of 1,782 to a high of 3,769 mg/m 3 



(corrected to 3% 0„ with an average yearly concentration of 2,895 as 



compared to 2,663 in 1989. Down time for the S0 ? in-stack monitor of 16% 



was the same as 1989' s. Nitrogen oxide averages in 1990 were virtually 



the same as those in 1989 with daily concentrations ranging from a low of 



336 to a high of 1,225 mg/m 3 (corrected to 3% 0„) with an average yearly 



concentration of 741 as compared to 774 in 1989. Down time for the NO 



x 



in-stack monitor was the same as 1989' s 16%. 



