Big Dig deal could hit $1b

State and federal officials are demanding that Bechtel/Parsons Brinckerhoff pay as much as $1 billion to settle claims for shoddy work on the Big Dig, in exchange for a guarantee that the consortium will not face criminal charges in last year's tunnel collapse that killed Milena Del Valle, according to four sources with knowledge of the negotiations.

Bechtel/Parsons Brinckerhoff, which was paid more than $2 billion to manage the design and construction of the Big Dig, would also be released from civil liability from the state and federal governments, the sources said yesterday.

The settlement would relieve Bechtel/Parsons Brinckerhoff of responsibility for any defects that become apparent after the agreement is signed, as well as those previously discovered on the $15 billion highway-and-tunnel project, such as the ceiling collapse and the leaks that continue to plague the Thomas P. "Tip" O'Neill Jr. Tunnel, the sources said.

All the sources have been briefed on the negotiations and spoke on condition of anonymity, because the private talks are still ongoing.

The other contractors involved in the project are not part of the settlement talks.

All the companies involved in the Big Dig, along with the Massachusetts Turnpike Authority, were faulted this week by the National Transportation Safety Board, which concluded that the wrong type of glue was used to hold up part of the ceiling that collapsed and killed Del Valle, of Jamaica Plain, on July 10, 2006.

The settlement negotiations have intensified in recent days as Attorney General Martha Coakley has twice postponed the self- imposed deadline she publicly set for herself to decide whether to seek indictments in the ceiling collapse. On Thursday, her office issued a short statement that said she needed "a short amount of additional time" to finish the criminal probe.

Coakley's office is most likely considering involuntary manslaughter or false claims charges against corporations and individuals involved in the design and construction of the ceiling. While the penalties for such crimes would probably be relatively modest fines, companies with worldwide reputations, such as those in the Bechtel/Parsons Brinckerhoff consortium, want to avoid being tarnished by any criminal conviction, say lawyers involved in the case.

A civil settlement with Bechtel/ Parsons Brinckerhoff would not directly affect the wrongful death lawsuit brought against the consulting consortium, other Big Dig companies, and the Turnpike Authority by Del Valle's family. Secret mediation talks broke down last month, with the sides far apart on a figure.

Before the tunnel collapse, Attorney General Thomas F. Reilly appeared ready to settle the government's civil claims against Bechtel/Parsons Brinckerhoff for $85 million.

That settlement, however, was scuttled by US Attorney Michael J. Sullivan, who said he believed it was premature and too generous to the consortium. While Sullivan said he stopped the deal, Reilly disputed that. Since about half of the funding for the Big Dig came from the federal government, Sullivan's office has conducted its own investigation of the management, design, and construction of the project and has shared jurisdiction over any civil settlement.

After Del Valle's death, Reilly filed a civil suit in November seeking $150 million from Bechtel/ Parsons Brinckerhoff.

The settlement under discussion -- at least $350 million, one source said, and as much $1 billion, others said -- would free Bechtel/Parsons Brinckerhoff from further action by both the state and federal governments.

According to one of the sources with knowledge of the negotiations, representing the US Attorney's office in the negotiations has been Fred M. Wyshak Jr., whose involvement in the Big Dig dates to 2004, when the Globe first disclosed the O'Neill tunnel was riddled with hundreds of leaks.

Christina DiIorio Sterling, spokeswoman for the US attorney's office, yesterday acknowledged the existence of an ongoing criminal investigation, but declined to answer questions.

Representing Coakley in the negotiations has been Paul F. Ware Jr., the prominent lawyer and a partner at the firm Goodwin Procter who was tapped by Coakley in March to lead the criminal investigation of the ceiling collapse. Coakley's office declined comment yesterday.

Representing Bechtel/Parsons Brinckerhoff has been David Kendall, a Washington lawyer who defended President Clinton during his impeachment trial.

A spokesman for Bechtel/ Parsons Brinckerhoff did not return telephone messages seeking comment yesterday.

In May, the Turnpike Authority disclosed a $210 million shortfall in its current funding, but said the agency expected to recover as much as $173 million from Big Dig contractors.

The Big Dig, first estimated to cost $2 billion and to be finished in 1998, has been lauded for many engineering achievements, especially the fact the tunnels were dug in downtown Boston beneath a still-operating major highway.

But its cost has ballooned, and three major design or construction flaws have been found since 2004. In September 2004, water burst through the wall of the northbound side of the O'Neill Tunnel, temporarily closing the highway. That breach was blamed on pockets of sand or gravel left within the 3-foot wide concrete walls, prompting managers to look for and repair scores of other such detects.

Later in 2004, managers acknowledged that there were more than 1,000 leaks in the O'Neill tunnel. The tunnel's design planned for no such leaks, but as recently as March, 1.9 million gallons of water was being pumped out each month.

The Turnpike Authority, which manages the Big Dig, acknowledged last month that hundreds of leaks remain and that plugged leaks are regularly reopening. Finding and plugging leaks is expected to continue indefinitely.

Last year, the third major defect was found when 26 tons of concrete came tumbling down in the Interstate 90 connector tunnel, killing Del Valle, a passenger in a car being driven by her husband to Logan Airport.

Estes can be reached at estes@globe.com; Murphy at smurphy@globe.com.