Big Dig Tests Reveal More Weak Bolts

Gov. Mitt Romney on Monday dramatically raised the number of potential trouble spots identified by engineers and investigators in a Big Dig connector tunnel where the ceiling collapsed.

Romney said that tests showed more than 1,100 bolt assemblies that used epoxies and more than 300 other areas in the tunnel were unreliable. All, he said, will have to be reinforced.

“In grabbing ahold of these bolts and pulling on them with excess force, they’re letting go ... at lower pressures than they were designed to handle,” Romney said.

Last week, days after 12 tons of ceiling panels came loose and fell on a car, crushing a passenger, the governor announced that inspections had found at least 242 points where bolts were separating from the tunnel roof.

Commuters endured increased traffic Monday with the closing of a second tunnel ramp connecting two interstates. The ramp was closed Sunday after tests showed problems with the bolts holding the ceiling. That ramp had been used as a detour around the accident scene.

The $14.6-billion Big Dig -- the most expensive highway project in U.S. history -- buried a highway network that used to slice through the city, replacing it with a series of tunnels. The project has been plagued by leaks, falling debris, cost overruns, delays and problems linked to faulty construction.

State Atty. Gen. Tom Reilly, who is considering involuntary manslaughter charges in the ceiling collapse, said Monday that investigators had discovered documents showing a “substantial dispute” in 1999 and 2000 over whether the design of the tunnel was adequate to hold the 3-ton ceiling panels.