The tunnel boring machine pictured below was built by Herrenknecht AG (which has an office in Tacoma), for a tunneling job in Madrid, Spain. Below the picture are links to three companies that are in the business of building these huge machines (they’re about 55-60 feet in diameter) and which are likely to be interested in getting the job to build a “drill bit” for the 1.7-mile deep-bore tunnel under First Avenue in Seattle to replace the Alaskan Way Viaduct.
Here is a link to Herrenknecht AG. This is a German firm with an office in Tacoma.
Here is a link to RobbinsTBM in Kent. Company HQ is in Ohio.
Here is a link to NFM Technologies. This is a French firm that recently was sold, to Mitsubishi, I think.