Weather Information for the three days indicates that strong winds were blowing 

 from a northerly direction. The power plant was not likely the source of 

 these elevated levels, but quite probably dust from fields north of the 

 monitoring site was responsible. The I982 annual geometric mean concentration 

 for suspended particulates was below the Saskatchewan standard of 70 ug/m . 



In-stack monitoring results have shown variability due to plant operation and 

 difficulties and changes in coal quality. In addition, considerable monitor 

 downtime was experienced during the year; however, instrument serviceability 

 has improved in the last half of I982. 



On the occasions when bunker oil was used as a fuel at the plant, unusually 

 high stack opacities were the result. This is attributed to a coating effect 

 which the oil has on the precipitator. Dally average opacities have generally 

 ranged from 20 to kO percent, with the lowest values occurring during uninter- 

 rupted coal firing. The SPC has an ongoing program of precipitator tuning and 

 experimentation with electrode and plate rapping sequences which has Improved 

 the performances of the unit. Precipitator efficiency was measured at greater 

 than 99 percent In June of I982. 



In-stack nitrogen oxides concentrations remained relatively constant, averaging 



■3 

 about 700 milligrams per cubic meter (mg/m ) . Daily average sulphur dioxide 



3 3 



concentrations have ranged from about 2000 mg/m to about 4000 mg/m , corresponding 



to changes In the sulphur content of the coal. The relationship of sulphur 



dioxide emissions to the firing with bunker oil is being investigated. 



26. 



