- 40 - 



Average daily opacity readings ranged from to 100 per cent, with 

 a yearly average of 26 per cent as compared to 16 per cent in 

 1986. Saskatchewan's opacity standard is 40 per cent. In most 

 instances opacity violations occur during unit start up or shutdown 

 sequences . The reason for this is that the precipitators are not 

 normally energized while a unit is fired on oil, in order to 

 minimize fouling of the precipitator plates and to improve overall 

 collection efficiency. During 1987 there were approximately 22 

 occasions, lasting for an average of just under 9 hours, when one 

 of the units was firing on oil and the precipitators were not 

 energized. These events gave rise to the majority of the opacity 

 violations that were recorded. 



On September 29, 1987, a manual stack gas survey was conducted at 

 this Poplar River Power. Plant. Using the results from this 

 verification survey, the annual average stack emission values can 

 be represented as follows: 



sulphur dioxide - 741.8 nanograms per joule of heat input 



or 

 1.72 pounds per million Btu of heat input 



nitrogen oxides - 223.0 nanograms per joule of heat input 



or 

 0.52 pounds per million Btu of heat input 



particulates 



23.8 nanograms per joule of heat input 



or 

 0.06 pounds per million Btu of heat input 



