Evaluating the radiological impact of uranium emissions in Port Hope, Ontario—A comparison of monitoring and modelling results

• Published in: Journal of environmental radioactivity Vol. 34; no. 2; pp. 187 - 205
• Main Authors: Ahier, Brian A., Tracy, Bliss L.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1997; Elsevier
• Subjects: Applied sciences; Atmospheric pollution; Exact sciences and technology; Pollutants physicochemistry study: properties, effects, reactions, transport and distribution; Pollution; Canada; North America; Ontario; America; Uranium production; Ambient air concentration; Radioactive pollution; Uranium; Emission content; Check; Air pollution; Atmospheric dispersion; Pollutant emission; Modeling; Meteorology
• ISSN: 0265-931X; 1879-1700
• DOI: 10.1016/0265-931X(96)00008-2

During 1988 and 1989, an environmental monitoring study was conducted to assess the possible health impact of airborne emissions from a Canadian uranium processing facility. Airborne U dust was collected using high-volume air samplers located within 2km of the facility. Weekly concentrations of U in air varied from the detection limit of 0.06 ng m −3 to 75.7ng m −3, with a geometric mean of 1.05ng m −3. Decreases in concentration during the summer facility slowdown period indicated that the observed levels of airborne U resulted primarily from processing operations, and not from the resuspension of previously emitted material. The committed inhalation dose to the nearest receptor from 1 year of facility operation was estimated to be 0.014 mSv. This was well below ICRP guidelines, and represented a small fraction of normal background radiation. No health effects would be expected at these levels. Results of the study were compared with the predictions of a longterm Gaussian dispersion model based on a hindcast approach to derive the best-fit emission rates. Predicted concentrations were generally within a factor of 2–3 of field observations. Discrepancies were due to inherent limitations of the model, uncertainties in the source emission characteristics, and variations between the long-term meteorological frequency distributions based on remote and local data.