All six of the bids were below the engineer's estimate of just under US$595m for the work.
Low bidder was JCM Northlink LLC, a joint venture formed by Jay Dee Contractors, Frank Collucio Õ¥Ö¼§ and Michaels Corporation with a bid of US$440.3m. In addition to the twin tunnels the contract includes excavating the underground stations in the Roosevelt and U District neighbourhoods.
The contract is the largest single piece of work on the US$2.1bn Northgate Link extension.
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