Air Pollution: Efforts To Control Ozone in Areas of Illinois, Indiana, and Wisconsin

In response to a congressional request, GAO evaluated Environmental Protection Agency (EPA) and state efforts to control hydrocarbon emissions in southeastern Wisconsin, northeastern Illinois, and northwestern Indiana, to determine: (1) whether Illinois and Indiana are contributing to Wisconsin's ozone problems; (2) why the two states have not obtained EPA approval of their ozone control plans; (3) why EPA failed to develop plans for the two states; (4) whether the EPA process for determining air quality violations across state lines is useful for ozone; (5) whether EPA uniformly implements construction bans nationwide; and (6) whether factories within the three states emit significant amounts of hydrocarbons.