Retired judge Edward M. Ginsburg is leading a team of lawyers and engineers to recover overcharges as high as $146 million from the Big Dig highway project in downtown Boston. The lawsuit claims that the project’s private-sector managers concealed true cost estimates from state officials to keep the project moving.

The lawsuit, approved by state Attorney General Thomas F. Reilly, states that Bechtel/Parsons Brinkerhoff cleared profits exceeding $140 million and $6 million in incentive fees out of total payments of $2 billion. This project is the largest public works project in U.S. history, and its estimated cost has increased from $2.6 billion to $14.6 billion. It’s scheduled for completion in 2005.