Clean Air Act - Inhibits Acid Rain

The original Clean Air Act was established by the Environmental Protection Agency (EPA) in the 1970s. At the time, there were few, if any, provisions made for the reduction od acid rain causing gases. Basically, the Clean AIr act  was the first major legislation aimed at cleaning up our air. Later, there were amendments made to the act. It is in these amendments that we obtained regulations for the production of both SO2 and NOx.

EPA released amendments to the Clean Air Act. In these amendments, EPA made provisions for acid rain, commonly known as Titile IV. Although the provisions affect only a small amount of the sources of acid rain gases, the improvements caused are expected to be significant. With the creation of Title IV, EPA implemented two new concepts. These concepts are:

1. Emissions Trading

2. National Emissions Cap

In order to accomplish its goals, Title IV established a nationwide system of SO2 emission allowances. These allowances are expressed in terms of tons of SO2 emitted per year, and the basic allowance is emission of 1 ton per year of SO2. It is important to note that no source affected by Title IV can emit SO2 without holding an allowance for the emission. If a source does this, it may have to face judicial action. Also, if a source want to increase production and therefore increase emissions, it must obtain an emission allowance from another source that has reduced emissions. This is known as emissions trading.

In addition to the SO2 reduction, Title IV calls for a 2 million ton reduction in NOx. This reduction will be accomplished through burner modifications and will be measured from the amount of NOx that would have been emitted, if no modifications had been made. In terms of NOx emissions, Title IV does not require that industries install post combustion controls for monitoring. Also, unlike the SO2 emission reduction program, there is no NOx emission allowance system or emission cap for NOx.

Major Problematic Areas in Canada Due to Acid Rain

Eastern Canada

The problem areas of Canada are primarily in the eastern provinces that lie on the Canadian Shield and, therefore, lack natural buffers. Ontario, Quebec, New Brunswick and Nova Scotia are the most significantly damaged by acid rain. Most of the emissions that impact eastern Canada are produced at the large metal smelters in central Ontario and Quebec. Emissions from the US also affect Canada’s eastern region. In the US, the greatest amount of emissions comes from a high density of coal fired power plants in the eastern states. Weather systems carry these pollutants from the upper mid western US states across southern Ontario, southern Quebec and into the northeastern US. Pollutants also travel up the northeast corridor of the US into the Atlantic Provinces. 

Western Canada

Major emissions sources that impact western Canada are located in Alberta (from upstream oil and gas production and oil sands), southern Saskatchewan (from electric power generation) and northern Manitoba (from mining and smelting). However, there is currently not enough information to tell us how acid rain is affecting these ecosystems. Historically, western Canada has experienced less industrialization than eastern Canada. This factor, combined with east wardly moving weather patterns and acid resistant soils, has so far protected much of western Canada from the damage of acid rain. Not all areas in western Canada are naturally protected. Some lakes and soils rest on granitic bedrock, such as is found in areas of the Canadian Shield, in northeastern Alberta, northern Saskatchewan and Manitoba, parts of western British Columbia, and the Northwest Territories . Ecosystems in these areas are as vulnerable to acid rain as those found in northern Ontario. Acid rain may also become a regional problem downwind of the Alberta oil sands projects, where rapid expansion of bitumen extraction industries is expected to cause large increases in emissions of SO2  and NOX  in the next 20 years. A big concern to scientists is that if SO2  and NOX emissions continue to increase in western Canada, the same sort of acid rain damage that has happened in eastern Canada could occur in the west.