More trouble spots were found in the Big Dig’s I-90 connector tunnel following a fatal accident on July 10 in which a motorist was killed when several heavy ceiling tiles (weighing approximately 3 tons each) crushed the victim’s car. The Massachusetts Turnpike Authority (MTA) has ordered an examination of every road and tunnel in its highway system, and the federal government is looking into the ceiling tile failure as well.
The preliminary cause of failure appears to be with the ceiling anchor bolts. According to officials, the tiles formed a drop ceiling and were fastened to the roof of the tunnel with metal tiebacks. The tiebacks were attached to the roof with bolts and epoxy glue. Reportedly, one of the tiebacks separated, causing a section of five concrete tiles to fall.
Since the accident, state inspectors have found at least 1,100 other locations where similar anchor bolts are "unreliable." MTA Chairman Matthew J. Amorello said the I-90 tunnel would be closed until inspectors could determine how to "make sure that event never happens again."
Alexander Bardow, the state engineer overseeing Big Dig tunnel inspections, told Providence, R.I., television station WPRI that lighter ceiling panels were originally chosen for the I-90 connector tunnel. He told the station that part-way through tunnel construction, Big Dig managers switched to a design that called for a heavier concrete ceiling. It was apparently less expensive and easier to install.
According to Massachusetts Attorney General Thomas F. Reilly, problems with anchor bolts used in I-90 tunnel were identified in tests conducted in 1999 when the ceiling was built. He told The New York Times that his office is investigating whether a plan to correct the problems was ever carried out.
The Big Dig project manager, Bechtel/Parsons Brinckerhoff, and the contractor for the connector, Modern Continental, are not speaking directly to the media, but companies did issue brief statements. Bechtel said it was "supporting efforts to investigate the accident, re-open the highway, and address public concerns," and that "we strongly believe that a comprehensive review … is essential to restoring public confidence in this historic project." Modern Continental said it was "confident that our work fully complied with the plans and specifications."
As if the accident and other, well-publicized problems (leaks, flaws in the slurry walls, and corruption charges filed against employees of a concrete supplier) are not enough, some are questioning the federal government’s role in the investigations because the newly appointed Federal Highway Administrator, J. Richard Capka, was once the MTA’s administrator on the Big Dig.
According to The Boston Globe, watchdog groups and Massachusetts lawmakers question how Capka can oversee his agency’s probe of the ceiling collapse, given that he headed the Big Dig project for 18 months until his dismissal in June 2002. The newspaper quotes sources that say Capka’s role is fraught with potential conflicts of interest. Even the appearance of conflict, they say, could drain public confidence in the investigation.
An FHWA spokesperson told the Globe that Capka is not involved directly with the federal investigation. It is being handled by an independent panel. "The agency is obviously very committed to conducting a very thorough and complete investigation and working with all the other entities doing the same thing," the spokesperson said.
The Big Dig is regarded as the country’s largest highway project. It took 15 years and nearly $15 billion to bury Boston’s central highway.