3.4. SR 08-25-1997 - Laserfiche WebLink

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Minnesota Pollution Control Agency June 1997 Facts about The MPCA's Monitoring Program for Toxic Air Pollutants The Legislature has authorized the Minnesota Pollution Control Agency to begin a statewide effort to monitor the ambient air (the outdoor air around us) for "toxic air pollutants." The agency began the program last year, and is now malting plans for placing the monitoring equipment in fiscal year 1998, which begins in July 1997. During the last ten years, concern has developed regarding a long list of substances that may be found in the air in smaller quantities but may be more toxic than the "criteria pollutants." Although the original six pollutants are also toxic in sufficient quantities, for lack of a better name, these other pollutants are often referred to as "toxic air pollutants." What are toxic air pollutants? For many years, the MPCA and similar agencies in other states have routinely monitored for a group of six air pollutants called "criteria pollutants": carbon monoxide, sulfur dioxide, nitrogen oxides, particulate matter (usually soot or dust), ozone and lead. These are substances that are found in air emissions from many types of sources and in relatively large quantities. These pollutants are hazardous to human health and the environment, and the U.S. Environmental Protection Agency has established limits (standards) for how much may safely be found in the air around us -- the ambient air. The EPA has identified 188 toxic air pollutants as "hazardous air pollutants" (HAPs) and is developing regulations for them. However, there are a large number of other toxic air pollutants for which there are no regulations and yet these other toxic air pollutants have been found in ambient air in studies conducted in urban areas in other states. Why are we monitoring for toxic air pollutants? Many questions remain about how much people are exposed to toxic air pollutants in the outdoor air in Minnesota and whether these concentrations pose a potential public-health risk. Printed on paper containing at least 10 percent fibers from paper recycled by consumers. Because not all of the substances result from human activities, we need to know what would be considered the "natural" or "background" level. How much are people in communities of various sizes exposed to? Which pollutants are likely to present the greatest risk? What kinds of air- pollution sources need to be controlled? State and federal regulations to require pollution control for toxic air pollutants are beginning to be established through the provisions of the 1990 Clean Air Act Amendments. However, establishing these regulatory requirements is a slow process and it is unknown how much these federal regulations will reduce ambient-air concentrations of toxic air pollutants. In addition to the federal program, pollution-control requirements exist now for solid- waste incinerators and for the substances that also contribute to smog. The MPCA also includes requirements to control toxic air pollutants in some air-emissions permits, on a case-by-case.basis. It is important to find out whether these pollutants pose potential risks to human health and if there is a need for these pollutants to be regulated further.