The approval is significant in that it is the project's first clean financial bill of health since it was discovered two years ago that the project had run up over $2 billion in cost overruns. From that point on, the federally subsidized project was required to give its finance plans to the Department of Transportation for evaluation every year. The approval means that additional federal funds for the project will be released and that the audit of the project will be withdrawn.

But it's not all good news for the Big Dig. One of its developers, Honeywell Technology Solutions, which is building the project's Intelligent Highway System, put in a claim that would nearly double the cost of its contract with the Massachusetts Turnpike Authority. The company's original contract to build the "nervous system" of the highway was for $104 million. The system would enable the highway to be the largest first fully integrated highway system in the country. The company wants another $91 million to complete the system, which would allow the highway to sense what drivers are doing and communicate with them. The system is used for traffic management and emergency response, among other things. The Turnpike Authority is investigating the claim.

The Massachusetts Port Authority has also put in a claim, albeit one that would have less egregious effects on the project. It wants to defer a $105-million payment, claiming it has other obligations that are more pressing. Massport was hit hard by the Sept. 11 terror attacks.