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      High-pressure job to free Seattle tunnel machine

      SEATTLE (AP) - The next step in the process to resume drilling a highway tunnel under downtown Seattle is to get a better look at what's blocking the path of the huge boring machine called Bertha.

      The state Transportation Department says the contractor, Seattle Tunnel Partners, plans to inject a material that will be inflated with pressurized air to create a "bubble" at the cutting head. That will give workers space to fix the problem.

      The workers will have to spend time in high-pressure chambers to adjust to the conditions.

      Drilling stopped Dec. 6 after Bertha ran into a pipe. Officials aren't sure that's the only problem.

      The new Highway 99 tunnel is part of the project to replace the Alaskan Way Viaduct on the Seattle waterfront.
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