Construction on a portion of the Brightwater Treatment System’s 13-mile conveyance tunnel has been temporarily suspended to enable repairs on a tunnel boring machine. Maintenance will also be performed during the repair work.
Because of reduced construction activity, Brightwater contractor Vinci/Parsons/Frontier-Kemper/RCI, a joint venture, made a decision yesterday to lay off about 60 construction workers, about 30 percent of the work force at the North Kenmore portal.
The machine is expected to be idle for several months so crews can repair a worn structural rim on the machine’s 17.5-foot-diameter cutter head. They also expect to repair or replace about 13 cutter disks.
The machine, called BT-2 or “Helene”, is currently about 320 feet underground and about 1.5 miles into the tunnel, so repairing it in place is the only option.
Crews began tunneling with the machine east from the Brightwater North Kenmore portal near the intersection of 80th Avenue Northeast and Northeast 195th Street in fall 2007. They have completed about 1.5 miles of the nearly two-mile segment of tunnel that terminates at the Brightwater North Creek portal at Northeast 195th Street and North Creek Parkway in Bothell.
The 350-foot-long slurry machine is manufactured by German firm Herrenknecht.
More information about the Brightwater Project is available at http://www.kingcounty.gov/brightwater.
Note to editors and reporters: Visit the WTD Newsroom, a portal to information for the news media about the Wastewater Treatment Division, King County Department of Natural Resources and Parks: http://www.kingcounty.gov/environment/wtd/Newsroom.aspx
This release is also posted on the Web site for the Department of Natural Resources and Parks at http://www.kingcounty.gov/environment/dnrp.aspx
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