The Clean Air Council sued United States Steel after a fire at the defendant’s plant led to pollution levels that violated the Clean Air Act. The Act runs on “cooperative federalism,” meaning the federal law allows local governments to implement and refine procedures to meet the law’s requirements. After the fire, United States Steel notified local officials who enforce the Act. The company did not alert federal officials. However, under the Comprehensive Environmental Response, Compensation, and Liability Act, some emissions, such as emissions “subject to” certain Clean Air Act permits and regulations, must be reported to federal authorities. Here, the Third Circuit interpreted the phrase “subject to” as it applies to the legislation. The Court held that the phrase means “governed or affected by,” as advocated by United States Steel. Because the emissions were governed or affected by the Clear Air Act, the Court concluded that the company was not required to report the pollution to federal authorities.