Today, as expected, the Federal Highway Administration signed off on the deep-bore tunnel project. The "record of decision" is an incremental stop on the tunnel project's journey, and essentially gives the state the go-ahead to start final design and construction of the project. According to the WSDOT, the decision also spells out certain measures intended to minimize impact—such as monitoring buildings and utilities while the tunnel's being bored and making up for lost parking (somehow).
According to WSDOT, after the decision was issued, the state directed Seattle Tunnel Partners to get cracking on phaes 2 of the contract. Construction precursors will begin this fall--relocation of utilities and final design and manufacturing of the tunnel boring machine. Here's a website to look at if you're going through tunnel-news withdrawal.