The moral questions remain

The car that was crushed by falling ceiling panels, killing passenger Milena Del Valle in a Big Dig Tunnel in Boston.

ANCHOR BOLTS, poorly secured by epoxy, failed.

That's the simple, technical answer to what caused the Big Dig ceiling collapse and the death of Milena Del Valle of Jamaica Plain.

But what motivated the human beings who installed those bolts? Who knew the bolts were coming out, but didn't stop the ceiling from going up? Who kept the problem as quiet as possible until tons of concrete crashed onto Del Valle, as she and her husband headed to Logan International Airport on July 10, 2006?

The civil suit filed by Del Valle's family ended with a $28 million settlement, to be paid by a raft of defendants, including construction contractor Modern Continental, project manager Bechtel/Parsons Brinckerhoff, and the Massachusetts Turnpike Authority.

It doesn't resolve the deeper, moral questions behind the beautiful, but fatally flawed, $15 billion public works project.

"The one thing we don't really know from any witness's mouth is 'Why? Why make those decisions?,' " said Boston lawyer Bradley Henry, who represented Del Valle's children in the case.

Four project engineers cited their Fifth Amendment right against self-incrimination and refused to testify, so "we can only infer as to why they made the decisions they did," Henry said.

Absent contrary evidence, it appears that some critical engineering decisions were influenced by fear - not fear of the consequences of building an unsafe tunnel, but fear of being responsible for cost overruns and project delays.

By Sept. 9, 1999, engineers knew anchor bolts were failing. Yet, they didn't set up a formal system for monitoring the bolts. Eventually, senior managers were told about the problem, but never got to the bottom of why. They knew the ceiling was falling down, but moved the project forward anyway. Instead of cross-checking their calculations, they crossed their fingers.

Investigations of the collapse turned up a string of failures. The National Transportation Safety Board faulted project manager Bechtel/Parsons Brinckerhoff and the Massachusetts Turnpike Authority for not taking steps to prevent the collapse; epoxy vendor Powers Fasteners; Modern Continental, which installed the bolts; and Gannett Fleming, which designed the tunnel ceiling.

Bechtel and several smaller companies agreed to a $450 million settlement to avert criminal charges. Powers Fasteners was charged with one count of manslaughter and Modern Continental faces criminal charges as well.

Legal accountability is one issue. What about moral accountability? Where does it begin and end?

From the start, elected officials low-balled the cost of the massive engineering project known as the Big Dig. To the benefit of a circle of insiders, the pricetag ballooned, and the construction timetable extended from one century to the next. Still, no governor or other official charged with representing the public interest looked the taxpayer in the eye and acknowledged the truth. For too long, the message to the public was "on time, on budget," even though the Big Dig was neither. Then, at a certain point, the frantic message to contractors was: "Just get it done."

Why didn't anyone in the public or private sector put the cost of a human life ahead of the cost of replacing failing bolts?

Because they were all afraid to tell the truth to the people driving under those tons of concrete. More time and money were necessary to fix mistakes the Big Dig's creators were too proud to admit. By 1999, no one in government thought a public lied to for years could handle the truth, or even believe it.

The Big Dig is a perfect example of what happens when the public and private sectors lose credibility together. A version of the same theme is playing out on Capitol Hill right now. The difficulty in reaching agreement on the terms of a financial rescue plan is a testament to the public's lack of confidence in either Wall Street or Washington.

The Big Dig also illustrates what happens when taxpayers and the media sit back and fail to ask tough questions from the outset. Over time, the lack of curiosity leads to a lack of oversight and accountability.

In this case, the end result was human tragedy.

Joan Vennochi can be reached at vennochi@globe.com.