AIR QUALITY 



Saskatchewan 



Ambient sulphur dioxide monitoring began at Coronach in July 1979. To 

 date, a few detectable concentrations have been recorded at this site. 

 There were no recorded violations of Saskatchewan Environment's hourly or 

 24 hour standards of 17.0 pphm and 6.0 pphm respectively (Figures 8 

 and 9). The highest value of 7.5 pphm occurred on November 12 at 1200 

 hours. Weather information for this day-indicates winds blowing from the 

 southwest quadrant, which would indicate the power plant as the probable 

 source. The highest 24 hour value of 0.4 pphm occurred on May 24 and 

 November 12. Weather data indicates winds blowing from the southern 

 quadrants 46 and 42% of the time respectively. 



Suspended particulate concentrations at Coronach did not exceed 

 Saskatchewan Environment's 24 hour average standard of 120 micrograms per 

 cubic metre (ug/m3/24 hours), as compared to 6 exceedances in 1984. The 

 annual geometric mean fell from 39.8 ug/m^ in 1984 to 24.8 ug/m3 in 1985 

 and continues to be well below the Saskatchewan standard of 70.0 ug/m3. 



In-stack monitoring results showed a similar variance in 1985 to that of 

 1984. Daily nitrogen oxide concentrations ranged from 400 to 1216 

 milligrams per cubic metre (mg/m^) with an average yearly concentration of 

 757 mg/m^ as compared to 800 mg/m^ in 1984. However, operating problems 

 continued to plague the nitrogen oxides monitor; the monitor was not 

 available 62% of the time. Daily sulphur dioxide concentrations ranged 

 from 1554 to 4710 mg/m^ with an average yearly concentration of 2660 mg/m^ 

 as compared to 2600 mg/m3 in 1984. 



