Attorney General Tom Reilly is seeking unspecified damages for repairs, loss of tunnel use and toll revenue and other economic factors, which could add up to more than $150 million.
"This lawsuit is more than just about money, although we will be seeking monetary damages," Reilly told CBS radio station WBZ-AM. "What this case is has always been about is the tragic death of Milena Del Valle. That could have been any one of us."
The lawsuit, to be filed in Suffolk Superior Court, alleges project manager Bechtel/Parsons Brinckerhoff and Modern Continental Construction Co. were "grossly negligent" in constructing the ceiling that collapsed. The suit also names Gannett Fleming, the Braintree firm that designed the I-90 connector tunnel; as well as the companies that supplied the epoxy or ceiling bolts used in ceiling panels that fell on a car in which Del Valle, a 38-year-old from Boston, was a passenger July 10.
At least 12 tons of concrete fell onto Del Valle's car. She and her new husband, Angel Delvalle, were headed to Logan Airport to pick up his brother and sister-in-law, who had been vacationing in his native Puerto Rico. He managed to crawl through a window of their crushed car to safety, and sustained only minor injuries.
Jeffrey Denner, a lawyer for the Del Valle family, said they are gratified that the state plans to sue.
"We're happy that the Commonwealth of Massachusetts is now standing up and essentially saying who's at fault here with their own investigation," Denner said.
Gannett Fleming also is being sued for breach of contract.
"The companies that were involved, starting with Bechtel/Parsons Brinckerhoff, Modern Continental, and the other companies ... were hired to do a job, to build a tunnel that was safe, and obviously it wasn't," Reilly told WBZ-AM.
A Bechtel/Parsons Brinckerhoff spokesman said the company hasn't seen the lawsuit and would not comment. Cambridge-based Modern Continental also refused comment.
Both organizations have in the past said they stand behind their work.
Del Valle's family in August filedagainst many of the same companies as well as the Massachusetts Turnpike Authority, the agency that oversees the $14.6 billion highway project.