also observed on December 20. The 1984 annual geometric mean of 39.8 

 Ug/m-^ is still well below the Saskatchewan standard of 70.0 pg/m^. 



In-stack monitoring results showed less variance in 1984, as a result 

 of improvements in plant operations. Daily nitrogen oxide concentra- 

 tions ranged from 620 to 1 593 milligrams per cubic metre (mg/m^) with 

 an average yearly concentration of 800 mg/m-^ as compared to 900 mg/m^ 

 in 1983. However, operating problems continued to plague the nitro- 

 gen oxides monitor in 1984. As a result data from April to December 

 are questionable and may represent only 50 percent of actual values. 

 Daily sulphur dioxide concentrations ranged from 2 168 to 3 120 mg/m-^ 

 with an average yearly concentration of 2 600 mg/m-^ as compared to 

 2 750 mg/m^ in 1983. Sulphur dioxide emissions consisted of 1.3 x 

 10~^ tonnes per megawatt hour due to firing on coal and 1.5 x 10 

 tonnes per megawatt hour due to firing on oil. 



Average daily opacity readings ranged from 18 to 76 percent, with a 

 yearly average of 22 percent. Saskatchewan's opacity standard is 40 

 percent. In most instances, opacity violations occurred when one of 

 the precipitators experienced a power trip. 



Montana 



The State of Montana operated three primary air monitoring sites and 

 five additional sulfation rate sites in the Poplar River area of 

 Montana from July 1984 through December 1984. The parameters moni- 

 tored included: sulfur dioxide, total suspended particulate, fine 

 particulates, sulfation rate, wind speed, wind direction, and temper- 

 ature. Poplar River air monitoring did not start until July of 1984 

 because the 1983 Montana Legislature provided funding for only 1 



- 33 - 



