The meteorological control of atmospheric pollution by heavy industry

The paper describes a method of reducing atmospheric pollution by varying the emission of the offending material with meteorological conditions. The details of the application of this principle by the Trail plant of the Consolidated Mining and Smelting Co. of Canada, Ltd., located in southern British Columbia, are given. The problem there is to prevent damage by sulphur dioxide to vegetation in the state of Washington. An investigation of the distribution of winds and SO2 in the Columbia River valley near Trail shows that, during growing season, the majority of fumigations are brought about by differential heating of the valley sides by the sun. Measured values of atmospheric turbulence and of wind speed and direction are fundamental in the control regime prescribed by the Arbitral Tribunal set up by governments of Canada and the United States. The possibility of applying this principle in other situations, and especially over level country, is discussed.