The tunnels throughout Boston's Big Dig highway system have been heavily scrutinized since a motorist was killed last week by 12 tons of falling concrete ceiling panels. Inspectors discovered more ...

The tunnels throughout Boston's Big Dig highway system have been heavily scrutinized since a motorist was killed last week by 12 tons of falling concrete ceiling panels. Inspectors discovered more ...

BOSTON (CBS) - Engineers say a space has opened up under one section of a Big Dig tunnel, and they can't fix it. When engineers built the tunnel system, they froze the soil in some places ...