The Environmental Protection Agency says several companies affiliated with National Car Rental are expected to pay a $475,000 fine for alleged idling violations at Boston's Logan International Airport and Bradley International near Hartford, Conn.
The consent decree must be approved in federal court.
The EPA said Monday that in 2006 and 2007 investigators observed shuttle buses carrying passengers from airport terminals to the rental car locations idling excessively.
At the time, Vanguard Car Rental USA Inc operated the National Car Rental facilities at Logan and Bradley. The current owners and operators of these facilities are Enterprise Rent-A-Car Company of Boston, LLC, and CAMRAC, LLC.
Laura Bryant, a spokeswoman for Enterprise, said before acquiring National the company made sure all idling concerns were addressed and corrected.