I suppose there was an abandonment hearing and report for the KEY system transit network in San Francisco/Oakland.

Anyone know where I could find a copy?

The Bay Bridge was built with two decks. The upper deck was 3 lanes each way for cars only. The lanes were narrow and separated only by a white stripe. Lots of head on accidents. The lower deck was the two Key tracks and three lanes for trucks and busses. The center lane was reversed depending on traffic. The system was a disaster and Cal Trans desperately wanted the Key off the bridge so they could convert it to 5 lanes on each deck, top deck west bound, bottom deck east bound. A political deal was worked out where the Key would get off the bridge and the Toll Bridge Authority would pay for an under water tube for rail transit.

The Key ran its last train on April 20, 1958 and the BART Transbay tube opened in 1974. The TransBay Tube cost the Toll Bridge Authority just under one billion dollars. I would recommend you read the book “The Key Route, Transbay Commuting by Train and Ferry” by Harre Demoro. The book is in two volumes.