The MBTA says Green Line and Orange Line service between Back Bay and North Station is now back up and running after several days of disruption.
The announcement comes one day after the agency said service would remain suspended for the remainder of the weekend due to ongoing concerns about a support column at the Government Center Garage.
"Following a comprehensive inspection of the infrastructure by internal and third party engineers and safety experts, an intensive assessment of the repair work performed, and subsequent testing of trains in the tunnels, the MBTA’s team of structural engineers have determined it is safe for both Orange and Green Line train services to resume, effective immediately," the MBTA said in a statement Sunday night.
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The MBTA had said it was aiming to have service back online by Monday morning, so long as it was deemed safe by engineers and safety experts.
The service disruption was first announced Thursday night, with the MBTA saying that HYM Construction, the contractor tasked with demolishing the garage, told the agency support columns in tunnels near Haymarket were "severely deteriorated," leaving them unsafe for trains to travel through.
MBTA General Manager Steve Poftak had blamed the contractor directly, but HYM said the issue was "unrelated" to its work."
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On Sunday, the MBTA said the Government Center Garage developer had installed the necessary supports to uphold the structure.
"Based on comprehensive inspections of the repair work, structural engineers and safety experts have deemed the structures and the surrounding infrastructure to be structurally sound," the MBTA said in its statement. "Following the successful testing of trains in the tunnel, Green Line and Orange Line train service can safely resume."
Structural engineers and safety experts will remain on scene to closely monitor the tunnel and infrastructure during daily Orange and Green Line operations, the MBTA said.
The agency also thanked all of its riders for their patience during this service disruption, infrastructure assessment, and service restoration in which the Green Line was replaced by shuttle buses between Government Center and Lechmere and the Orange Line was suspended between North Station and Back Bay.
Boston police said Sunday night that all streets around One Congress are now open. This is part of the same project where construction worker Peter Monsini was killed in a structure collapse in late March.
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