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AIR QUALITY 

 Saskatchewan 



Saskatchewan Environment and Public Safety 



Ambient air monitoring to determine sulphur dioxide (S0„) levels in the 

 vicinity of the Poplar River Power Plant began in 1979. The monitoring 

 station is located on the southern outskirts of the town of Coronach, 

 approximately 4.0 kilometres directly north of the power plant which in 

 turn is 5.0 kilometres north of the Canada/USA border. Saskatchewan 

 Environment and Public Safety's hourly and 24-hour average standards for 

 sulphur dioxide are 0.17 parts per million (ppm) and 0.06 ppm, 

 respectively. There have been no recorded violations of the 24-hour 

 average over the past 10 years. The hourly standard has been violated 

 twice during the same period. Both violations occurred on June 22, 1984, 

 at 1100 and 1200 hours with consecutive readings of 0.20 ppm. Weather 

 information obtained at the station indicated winds blowing from the 

 southeast quadrant at the time. As the power plant is located south of 

 the monitoring locations, it was the most probable source. Down time for 

 the monitor during the past 11 years has ranged from a low of 1.8% to a 

 high of 54% , for an average of 15.9%. Figures 63 and 64 show in 

 graphical form, maximum hourly and daily (24-hour) average readings, for 

 the past 10 years. 



Suspended particulate concentrations obtained from the high volume 

 monitor at the same location during the past 10 years indicate at total 

 of 26 violations of the provincial standard of 120 micrograms per cubic 

 meter (mg/m 3 /24 hrs) . The highest yearly number of violations occurred 

 in 1981, with a total of 8. The largest single concentration of 1,276 

 micrograms (M.g) occurred in 1981, on April 16, during a severe dust 



