On September 12, 2022, EPA and APS Technology, Inc. (APS) entered into an expedited settlement agreement (ESA) to resolve alleged Clean Air Act (CAA) regulatory violations at APS?s facility in Wallingford, Connecticut. APS manufactures equipment used in oil and gas drilling and operates one diesel stationary reciprocating internal combustion engine (RICE) to power the system that circulates water through its equipment. EPA alleged that APS violated the RICE National Emission Standards for Hazardous Air Pollutants (NESHAP) by failing to test (and retest) the engine and by failing to develop a complete site-specific monitoring plan, conduct annual performance evaluations of the continuous parameter monitoring systems associated with the engine, and submit applicable notifications and reports. APS corrected its violations after being contacted by EPA. The ESA was authorized under EPA?s Expedited Settlement Agreement Pilot Program for CAA stationary source cases. Under the ESA, APS will pay a settlement penalty of $45,828. This enforcement action is part of an EPA National Compliance Initiative for creating cleaner air for communities by reducing excess emissions of harmful pollutants. The Connecticut Department of Energy and Environmental Protection participated in the inspection and has been notified of this settlement.