The United States and the State of Utah filed a complaint and consent decree concurrently against Chevron U.S.A. seeking mitigation relief and civil penalties under the Clean Air Act for alleged violations at a Chevron petroleum refinery in Salt Lake City, Utah. The complaint alleged that Chevron failed to obtain the necessary prevention of significant deterioration permit and install controls to reduce nitrogen oxides. Pursuant to a consent decree, Chevron agreed to install pollution controls at the refinery and pay a $384,000 civil penalty.