Drilling toward the light (rail)
Seattle Times staff reporter
One of the biggest challenges of Sound Transit's light-rail project begins next week, when a behemoth drill starts burrowing through the soggy soil of Beacon Hill.
The transit agency is building twin one-mile tunnels that begin near Tully's along Interstate 5 and end near Franklin High School in Seattle's Rainier Valley. Drilling will continue through late 2007, with the line scheduled to carry riders between downtown and Seattle-Tacoma International Airport beginning in 2009.
Officials on Wednesday christened the drill with bottles of champagne and sake. Japan-based Mitsubishi custom-built the machine, nicknamed "Emerald Mole," to tackle the loose earth that ancient glaciers deposited here.
The machine's circular nose contains rotating teeth that grind through the dirt only twice a minute, instead of a speedier drill bit that would chip through solid rock, explained Paul Zick, project director for lead contractor Obayashi.
As the device disappears into the hillside, a conveyor belt will pull out the dirt through the rear. Meanwhile, a robotic arm will install concrete rings behind the drill, forming the permanent tunnel — quickly, before the wet dirt caves in.
Since last March, crews have been digging vertical shafts for a station atop Beacon Hill, where elevators will take people 165 feet down to the train tracks. The soil there was so unstable that grout had to be injected into it.
Much of the rail line is being built on the surface or elevated. By building a $280 million tunnel through Beacon Hill, the agency avoids putting tracks at street level along congested Rainier Avenue South near the north end of the hill.
As Seattle Mayor Greg Nickels and U.S. Sen. Patty Murray, D-Wash., spoke in praise of mass transit, a few demonstrators said African Americans aren't getting enough of the light-rail jobs.
"This community was promised our people would be hired, and we don't see that," said demonstrator Patricia Paschal.
Sound Transit chief executive Joni Earl, after shaking hands with the group, said, she discussed the issue last week with activist Eddie Rye.
"We're working on this," she said.
According to Rye, Obayashi is failing to hire black-owned subcontracting firms for available work. Sound Transit said African Americans have worked 9 percent of the hours under Obayashi's contract.
Copyright © 2006 The Seattle Times Company