Clean air goes to the U.S. Supreme Court

Elizabeth Wheeler

Clean air advocates await two U.S. Supreme Court decisions that will interpret the requirements of the Clean Air Act.

Environmental Defense v. Duke Energy Corp

The first case, Environmental Defense v. Duke Energy Corp, was argued on November 1st, 2006. The Duke Energy case addresses which sources are subject to the “prevention of significant deterioration” (PSD) standard under the Clean Air Act. This standard requires pollution control updates when a plant goes through modifications that increase pollution. The PSD standard is intended to merely maintain, not improve, regional air quality when pollution sources expand. The case was originally brought by the EPA against Duke Energy for violating PSD requirements. The EPA, at the time, defined PSD applicability as to any modification that resulted in increased emissions, measured in tons per year. Duke countered that the PSD definition could not differ from the New Source Performance Standard definition, which measured increased pollution in emission rates. Thus, under PSD, a modification that resulted in the plant increasing its operation time but not its emission rate, the plant would still have to meet PSD requirements. However, a plant that increased its emission rate would have to meet the same standards as a new source. Thus, PSD has a lower bar for what constitutes an increase.

The Duke Energy case involves several procedural issues – but the outcome will determine whether the EPA’s rule (and cleaner air) will be upheld or overturned. This case will affect mostly old, outdated power plants – the source of 70 % of Wisconsin’s energy. Having a lower bar for requiring pollution control updates on these facilities for prevention of significant deterioration (of air quality) is important – especially with regard to facilities such as the Valley power plant in Milwaukee. The Valley power plant was grandfathered in under the Clean Air Act and has very few pollution controls. It spews tens of thousands of tons of nitrogen oxides and sulfur dioxide into Milwaukee’s air and contributes to mercury pollution in Wisconsin. Valley is just one of many old, grandfathered power plants in Wisconsin that, if Duke succeeds in challenging EPA in this case, will be subject to less stringent air pollution rules under the Clean Air Act.

Massachusetts v. EPA

The second, more well-known case, Massachusetts v. EPA, was brought by twelve states, three cities and thirteen environmental groups in an attempt to force the EPA to regulate carbon dioxide emissions from cars. This case is part of the environmental movement’s attempt to address global warming. The arguments, heard on November 29th, focused on whether regulation of carbon dioxide from cars in just the United States would have any real impact on global warming. The clean air advocates argued that it would, and that the United States had to regulate carbon dioxide to set an example for the rest of the world. The EPA countered with the argument that regulating carbon dioxide on an ad-hoc basis through existing laws would be much less efficient than drafting new regulations that would target carbon dioxide.

The outcome of the Massachusetts case could hold EPA accountable for neglecting its duties under the Clean Air Act. Just because carbon dioxide was not considered a harmful pollutant when the Clean Air Act was drafted in 1970 does not mean that it is not a harmful pollutant today. Indeed, global warming has become one of the most critical environmental problems of our time, and reducing atmospheric carbon dioxide has been identified as the single most important step in stopping it. The outcome of the Massachusetts case will help to determine how quickly – and by what means – we begin to attack the problem of global warming on the national stage.