Sort of correct. IIRC, I believe they tested it once at the factory and blew out the bearing. Reassembled it - and sent it overseas to Seattle with no design change!
I know a guy that was/is involved in the tunneling. He said that in the Los Angeles, CA area he has worked on all sorts of tunnels. And all sorts of old abandoned oil wells. He said they would just tunnel through them with no problem.
He did say that some think that the lighter metal and smaller diameter of the test boring casing was not cut through - but rather bent and crimped and wrapped into the cutters and affected the seals and the bearings.
But - he wasn’t buying that explanation.
I have to admit - I didn’t think they would get it done. If it weren’t for the bearing failure (it was the largest boring machine by far at the time), they would have come out okay.
The viaduct was a death trap waiting to happen in the next large earthquake. And yes, Seattle traffic will probably just get worse.
> “If it weren’t for the bearing failure (it was the largest boring machine by far at the time), they would have come out okay.”
That is sort of like Custer saying that “If it weren’t for the Indians, they would have come out okay.”