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on two occasions In 1986. The highest recorded value of 161.9 

 yg/m-^ occurred on December 10. Weather data for this date Indicate 

 winds were blowing from the western quadrants for 65 percent of the 

 time, which would suggest that the power plant was not the source. 

 Windblown dust from fields west of the monitoring station was the 

 most probable cause. The annual geometric mean of 28.0 Ug/m^ is 

 well below the provincial standard. 



In-stack monitoring results showed a variance in 1986 similar to that 

 of 1985. Daily nitrogen oxide concentrations ranged from 276 to 2,161 

 milligrams per cubic metre (mg/m^) with an average yearly concentra- 

 tion of 898 mg/m^ as compared to 757 mg/ur in 1985. Ongoing improve- 

 ments to the sample conditioning system improved the operation of 

 the nitrogen oxides monitor considerably. The monitor was available 

 82 percent of the time in 1986 as compared to 38 percent of the time 

 in 1985. Dally sulphur dioxide concentrations ranged from 1,445 to 

 4,677 mg/m^, with an average yearly concentration of 2,688 mg/va? as 

 compared to 2,660 mg/wr in 1985. The sulphur dioxide monitor was 

 available 85 percent of the time in 1986. 



Sulphur dioxide emissions consisted of 9.2 x lO"-* tonnes per megawatt 

 hour due to firing on coal and 8.1 x 10~^ tonnes per megawatt hour 

 due to firing on oil. Total coal consumption for 1986 was 3,342,028 

 tonnes and oil consumption was 1,997 tonnes. 



Average daily opacity readings ranged from 1 to 100 percent, with a 

 yearly average of 16 percent as compared to 19 percent in 1985. 

 Saskatchewan's opacity standard is 40 percent. In most instances, 

 opacity violations occur during process startup, shutdown or when 

 one of the precipitators experiences a power trip. 



