Department of Justice (DOJ) and U.S. Environmental Protection Agency (EPA) concluded a federal judicial Consent Decree with Apache Nitrogen Products Inc (ANPI) of Arizona for ANPI's violations of the Arizona (AZ) State Implementation Plan (SIP) air quality regulations and of the Clean Air Act (CAA) standards of performance for new sources of air pollution at its nitric acid plant in Cochise County, Arizona. Under the Consent Decree, ANPI paid a civil penalty of $600,000 and must perform a computer simulated air flow study for the nitric acid production unit to determine the feasibility of control technologies to prevent nitrogen oxide emissions. Upon completion of the study, ANPI will install Best Available Control Technology (BACT) under the direction of the Arizona Department of Environmental Quality (ADEQ). EPA/DOJ enforcement team consulted with ADEQ regarding ADEQ's role in ensuring ANPI's compliance with the Consent Decree requirements.