An evaluation of air quality at two sites in the lower townsite of Fort McMurray, October 1, 1991 to June 30, 1992

Air quality data collected at two monitoring locations in Fort McMurray, Alberta, from October 1991 to June 1992 are summarized and evaluated. The data analysis includes a comparison of daily average pollutant concentrations at the two stations, the cumulative frequency distribution of the 1-hour average pollutant concentrations, the frequency of times that air pollution regulations were exceeded, and an analysis of the H2S and SO2 concentrations greater than their respective odor thresholds. It was found that SO2 and H2S showed a greater frequency of high concentrations at the Athabasca River Valley location compared to the downtown location. This is attributed to transportation of those pollutants down the valley during stable meteorological conditions with light northerly winds. H2S concentrations greater than the 3.5-ppB odor threshold were also more frequent at the valley location, while SO2 concentrations were below this threshold during the monitoring period. H2S and SO2 concentrations were found to be much greater during times of odor complaints than average values for the entire monitoring period. The odors which prompt complaints are likely caused by sulfur compounds originating from the oil sands plants to the north of the city. Pollutants such as CO and particulates, produced by urban sources, were generally higher at the downtown monitoring location. It was determined that the valley site was the most suitable location for monitoring air pollutants transported into the lower townsite of Fort McMurray from the oil sands facilities. 11 refs., 11 figs., 8 tabs