This enforcement action alleged violations of the Standards of Performance for Nitric Acid Plants at PCS Nitrogen Ohio, LP in Lima, Ohio. Specifically, PCS failed to include excess emissions of nitrogen oxides which occurred during start-up, shut-down and/or malfunction in its quarterly excess emission reports. Shortly after receiving notice of the alleged violations, PCS met with us and submitted revised excess emission reports which included excess emissions which occurred during start-up, shut-down and malfunction.