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Big Dig collapse aftershocks still felt

Safety agency will issue findings today

One year after massive concrete slabs fell from the ceiling of the Interstate 90 connector tunnel, instantly killing a 38-year-old mother of three, the aftershocks of the tragedy continue to reverberate across state government, within a family touched by tragedy, and in the minds of commuters who pass through the tunnels each day.

Today at a hearing in Washington, the National Transportation Safety Board is scheduled to issue a long-awaited report of the agency's findings on the cause of the tunnel collapse. Attorney General Martha Coakley is expected to announce soon whether she will seek criminal indictments against anyone involved in the tunnel's construction.

Milena Del Valle's family continues to come to grips with her death. Her husband, Angel, will attend a memorial service in Jamaica Plain this evening, joined by her daughter, Raquel Ibarra Mora, 24, who will travel to Boston after spending the day at the hearing in Washington.

"It's almost incredible to have your mother or your spouse torn away from you, and it's dramatically exacerbated by the senselessness of her death," said Brad Henry, a lawyer for the Del Valle children. "It haunts people. It's hard enough to lose a mother or spouse, but to lose them through a purely avoidable tragedy makes it that much harder to cope with and to get over."

The Big Dig had been plagued for years by reports of corruption, leaks, and cost overruns, but Del Valle's death on July 10, 2006, took concerns about the megaproject to a new level, especially after reports emerged that shoddy construction and inadequate oversight might have contributed to the tragedy.

A year after the event shook the public's confidence in the tunnel, Turnpike officials say there is now no reason to doubt its safety.

"Is the tunnel safe to drive through? The answer is absolutely yes," said state Transportation Secretary Bernard Cohen, who recently became chairman of the Turnpike Authority. "There's no denying the fact that we had the kind of catastrophic event in that tunnel that is everyone's worst nightmare. We are continuing to look at problem areas within the tunnel structure, but those problem areas, at least in the opinion of all the experts who have looked at this, do not rise to an issue of fundamental safety."

Yet, the images of the piles of concrete rubble that rained down on Del Valle's car last summer still haunt some commuters, like Will Alvarez, 27, of Dorchester, who said he doesn't feel safe traveling through the tunnel.

"All that concrete can come down at any time," he said yesterday as he ate lunch on the Boston Common. "If it happened once, what makes you think it couldn't happen again?"

Inspections of the tunnel immediately after the tragedy concluded that the concrete panels that crushed Del Valle's car fell because large bolts secured to the tunnel roof with epoxy came loose. The Globe has since reported that federal and state criminal investigators are focusing on whether contractors used the wrong adhesive to install at least some of the bolts in the area where the ceiling collapsed.

It was not until June, nearly 11 months later, that the Turnpike Authority reopened the last lane of the connector tunnel after replacing all the bolts secured to the roof with epoxy. Over the past year, the Turnpike also conducted a review of the other structural systems in the Big Dig, pronouncing them fundamentally safe.

But Cohen said that some structural problems remain. Concrete in the Thomas P. O'Neill Tunnel, which replaced the Central Artery, has started to fragment, requiring considerable repairs. Roads in the same tunnel have also begun to deteriorate, he said.

This summer, the Authority will begin a yearlong inspection of the remaining pieces of the metropolitan highway system: the Sumner and Callahan Tunnels, as well as the Central Artery North tunnel in Charlestown.

The ceiling collapse led to dramatic changes in the leadership of the quasi-independent Turnpike Authority. Governor Mitt Romney, who had long sought the ouster of Matthew J. Amorello, then the Turnpike Authority chairman and chief executive, finally prevailed. Amorello was forced to resign and was replaced by Romney's transportation chief, John Cogliano, who was replaced by Cohen after Governor Deval Patrick took office.

As state and federal officials continue their review, lawyers for Del Valle's family are pressing a massive lawsuit against the Turnpike Authority and more than a dozen contractors, a claim that has spawned at least 172 counterclaims among the defendants and engaged the services of more than 100 lawyers. Recent efforts to settle the lawsuit, which plaintiffs argue is worth hundreds of millions of dollars, were unsuccessful.

Lawyers for Del Valle's family said their clients are eagerly awaiting today's report, which will provide investigators' findings on the cause of the accident and who is responsible, as well as safety recommendations.

"This is a very sad day, but we tend to look at it as the beginning of all the answers," said Jeffrey Denner, who represents Angel Del Valle. "Rather than dwell on that sadness, we're going to build on it. We're very hopeful we will now find out the truth underlying this horrible tragedy and be able to establish just accountability."

Coakley and US Attorney Michael J. Sullivan are pursuing their own investigations as to whether to press criminal charges against those involved with the connector's construction.

Patrick said he was not given an advance copy of the safety board's findings.

"I'm as anxious as anyone to see what the report has to say," he said.

David Luberoff, executive director of Harvard University's Rappaport Institute for Greater Boston, said the safety board report could shed some light on who was responsible, but that the tragedy brought with it larger lessons.

"What I hope we take away from it is the importance of vigilance on the stuff that really matters, even when that means sometimes having to cut against the grain," he said.

April Simpson of the Globe staff contributed to this report.