Eight of the 23 midwestern and southeastern states launched an appeal after the EPA issued a rule in October 1998. The rule was issued following the EPA’s identification of the source of air pollution drifting into several eastern states, raising levels of ground-level ozone.
The EPA directed the 23 states to develop a plan to reduce nitrogen oxides (Nox). The federal appeals court ruled that the EPA’s plan to require reductions of ozone precursors in 23 states upwind of ozone non-attainment areas is reasonable and consistent with the agency’s authority under the Clean Air Act.
The court decision is part of a long running dispute between the regions and the federal government over interstate air pollution. For over a decade, the cities of the north eastern US have been accusing Midwestern power stations of polluting their air. Midwest power utilities and politicians have always denied the claim (see related story).
“Air pollution knows no boundaries. For the first time, states that contribute to smog in downwind states are required to become better neighbours,” said Lois Schiffer, Assistant Attorney General for Environment and Natural Resources.
In late 1998, eight states – Michigan, Ohio, Virginia, Alabama, Indiana, South Carolina, North Carolina and West Virginia – sued the EPA, joined by a number of industry groups. The petitioners claimed the EPA’s rule exceeded the agency’s authority under the Clean Air Act to address interstate air pollution.
The appeals court decision holds that:
- the EPA’s ozone precursor reduction plan is consistent with the agency’s authority under the Clean Air Act
- the EPA was not required to consult a multi-state commission on pollution-reduction measures before demanding new interstate air pollution plans
- the EPA’s method of determining the air pollution contributions of the 23 states was correct
- the EPA took into account the cost of air pollution controls when it determined which states should reduce their emissions, and the amount by which each state must reduce its emissions
However, the court decided that the EPA’s final rule would not apply to three of the states – Wisconsin, Missouri, and Georgia – until their cases are considered further.