EPA v. MBTA ARBORWAY

Case summary

On September 11, 2026, EPA Region 1 settled a Clean Air Act ( CAA ) enforcement action with Massachusetts Bay Transportation Authority ( MBTA ). MBTA owns and operates fleets of school buses at locations nationwide. This settlement resolves MBTA's alleged violations, on three days in two Massachusetts locations, of federally enforceable anti-idling requirements in the Massachusetts state implementation plan ( SIP ), which prohibits motor vehicles from idling for more than five minutes with certain exceptions. Pursuant to the terms of the consent agreement and final order, MBTA has agreed to pay a $73,066 penalty. Additionally, MBTA has voluntarily spent more than $300,000 on the implementation of a geofencing system for its bus fleet to reduce excessive idling and ensure compliance with the Massachusetts SIP. Diesel exhaust exposure can lead to or worsen serious health conditions including respiratory illnesses and permanent lung damage, particularly in the elderly and children. EPA provided the Notice of Violation to the Massachusetts Attorney General's Office and the Massachusetts Department of Environmental Protection ( MassDEP ) and provided MassDEP with a copy of this settlement.

Defendants (1)

• Massachusetts Bay Transportation AuthorityNamed in complaintNamed in settlement

Facilities (1)

• MBTA ARBORWAY GARAGE

  3600 WASHINGTON STREET, BOSTON, MA, 02130

  Registry ID: 110071958132

Statutes cited

• CAA 110 — Implementation Plan for National Primary and Secondary Ambient Air Quality Standards

Enforcement conclusions (1)

• MBTA ARBORWAYentered 2026-09-11

  Primary law: CAA

  Federal penalty: $73,066

Timeline (3 milestones)

• 2026-09-11Complaint Filed/Proposed Order
• 2026-09-11Final Order Issued
• 2026-09-14Enforcement Action Data Entered