The United States Navy operates four large diesel-powered engines that generate electricity at the Naval Computer and Telecommunications Area Master Station, Atlantic Detachment, in Cutler, Maine. The engines are subject to the National Emission Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines (RICE), found at 40 CFR Part 63, Subpart ZZZZ (Subpart ZZZZ). Given the size of these engines, Subpart ZZZZ requires that the engines have add-on emission controls by May 2013, but the Navy failed to install the controls by the required date. After an EPA inspection and the issuance of a Notice of Violation, the Navy installed a control on one engine by September 20, 2016, and on all engines by February 20, 2017. The Navy?s failure to timely install emissions controls led to the excess emissions of 28 tons of diesel-related hazardous air pollutants. In a Consent Agreement and Final Order, the Navy has agreed to comply with Subpart ZZZZ and pay a penalty of $811,000.