Impact of geophysical and meteorological conditions on the dispersion of NO2 in Canada

This study uses the CALPUFF modeling system to examine the impact of a region’s geophysical and meteorological conditions on the dispersion of nitrogen dioxide (NO₂) emitted from a new oil refinery proposed by the Newfoundland and Labrador Refining Corporation. The proposed construction site of the refinery in Placentia Bay in Newfoundland is compared to the three Canadian locations of Edmonton, Yarmouth, and Whitehorse due to the differences in their geophysical and meteorological conditions. NO₂ was selected as the modeled contaminant for this study due to the many severe ecosystem, health, and societal risks associated with its exposure to humans, animals, and the environment. Differences on the impact of each studied region’s geophysical and meteorological conditions led the proposed construction site in Newfoundland to be the only advisable construction site for this refinery out of the four regions examined. Although Yarmouth is also a coastal region, its geophysical and meteorological conditions cause NO₂ to disperse into the land, while in Newfoundland, NO₂ is dispersed over water. The maximum NO₂ concentrations simulated for Edmonton and Whitehorse are considerably high and exceed the NO₂ limit for at least one of the two standards proposed by the Newfoundland and Labrador Department of Environment and Conservation and the National Ambient Air Quality Standard. Results show that a region’s geophysical and meteorological conditions have large impacts on the dispersion of pollutants and require careful consideration when selecting a refinery site.