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Press Release

Massachusetts Bay Transportation Authority to Spend Millions to Reduce Commuter Train Emissions in Clean Air Act Settlement

For Immediate Release
Office of Public Affairs

WASHINGTON – In response to a federal enforcement action for excessive train engine idling, the Massachusetts Bay Transportation Authority (MBTA) and the Massachusetts Bay Commuter Railroad Company (MBCR) will spend more than $2 million to reduce diesel locomotive emissions throughout the MBTA’s commuter rail system, the Justice Department and Environmental Protection Agency (EPA) announced today. Under a consent decree lodged in federal court, MBTA and MBCR will spend over $1 million on anti-idling equipment at all end-of-line stations and maintenance facilities, and will spend another $1 million on ultra-clean diesel fuel for all trains in the commuter rail system for two years.

These emission-reducing measures are the result of a federal enforcement action brought by the Justice Department on behalf of EPA in response to MBTA’s and MBCR’s excessive locomotive idling at the Widett Circle layover facility in South Boston and the Greenbush line station in Scituate, Mass. Neighboring residents have complained of excessive train idling at both locations.

To settle the enforcement action, MBTA and MBCR will:

  • Install or upgrade electric plug-in stations as anti-idling equipment to supply all commuter locomotives with electric auxiliary power to prevent excess idling during train layovers;
  • Switch to cleaner burning, ultra-low sulfur diesel fuel for all trains on the MBTA’s commuter rail lines for a two year period at an estimated cost of $1 million;
  • Install new, less polluting auxiliary engines on fourteen commuter locomotives by no later than December 2012; and
  • Pay a $225,000 fine.

The anti-idling measures, clean diesel fuel switch and new auxiliary engines required by the federal settlement will have significant clean air benefits. For example, a reduction in commuter locomotive idling by even one hour per day per locomotive, together with the fuel switch and new engines, could result in yearly carbon dioxide emission reductions of an estimated 800 tons, nitrogen oxides reductions of nearly 170 tons, carbon monoxide reductions of about 80 tons, particulate reductions of 23 tons, and sulfur dioxide reductions of 1-2 tons.

MBTA owns 80 commuter locomotives used on 13 commuter rail routes in Eastern Massachusetts. Since 2003, MBCR has managed and operated the commuter train system for the MBTA. The system includes 14 layover facilities where the locomotives and passenger cars are parked and serviced between runs. Electric plug-in stations at these facilities supply the trains with electric power for lights and ventilation. If a plug-in is not available, a train on layover idles its auxiliary diesel engine to supply any needed electric power.

Under today’s settlement, which must be approved by the court, commuter train layovers will only be allowed at locations where there are sufficient electric plug-in stations for all trains.

The Massachusetts locomotive idling regulation, a federally-enforceable state regulation, prohibits all unnecessary diesel locomotive idling for more than 30 minutes. According to a 2008 notice of violation issued by EPA, MBTA and MBCR committed 33 violations of this regulation at Widett Circle and Greenbush in three months. At Widett, the average idling time during the violations was just under four hours (234 minutes).

“This precedent-setting, multi-million dollar settlement for train idling is appropriate in light of the defendants’ conduct,” said Ignacia S. Moreno, Assistant Attorney General for the Justice Department's Environment and Natural Resources Division. “The settlement will provide immediate and lasting environmental benefits to the residents of Eastern Massachusetts, particularly those in environmental justice communities.”

“It is imperative that anti-idling laws are followed, given the proximity of these layover facilities to densely-populated communities and environmental justice neighborhoods,” said Curt Spalding, regional administrator of EPA’s New England Office. “Diesel pollution can be very harmful, especially to sensitive populations such as the young, elderly and people who suffer from asthma.”

Diesel emissions contribute to a number of serious air pollution problems such as smog, acid rain and increased carbon concentrations in the atmosphere. Diesel exhaust contains fine particles that can cause lung damage and aggravate respiratory conditions, such as asthma and bronchitis. Based upon human and laboratory studies, there is also considerable evidence that diesel exhaust is a likely carcinogen.

Since 2002, EPA has brought more than a dozen federal enforcement cases to stop diesel engine idling violations in Mass., Conn. and R.I. Most of the cases have involved diesel truck and bus idling, including a judicial settlement announced in July 2010 against National Car Rental for shuttle bus idling at two airports. Only Massachusetts and Rhode Island have federally-enforceable locomotive idling regulations, and today’s action marks the first time EPA and DOJ have sued a railroad for excessive idling violations.

The consent decree, lodged in the U.S. District Court, will be subject to a 30-day public comment period and approval by the federal court. Once it is published in the Federal Register, a copy of the consent decree and instructions on how to comment will be available on the Justice Department Web site at

Diesel exhaust and anti-idling guidelines ( )

Updated April 4, 2024

Press Release Number: 10-896