UPDATE 4:02 p.m.: A worker was lowered 60 feet into a vertical, five-foot diameter exploratory shaft Thursday, but his visual search for an object blocking the tunnel drill was inconclusive, the DOT said Friday. Three of four planned shafts have been drilled. (Earlier, the agency had said it would not lower a person there.) The team expects to make additional searches.
POSTED FRIDAY MORNING:
Highway 99 program administrator Todd Trepanier didn’t use the word “patience,” but that was the theme of an email he sent Thursday to state lawmakers and the Transportation Commission, about the push to get tunnel machine Bertha moving again.
The giant drill has been stranded 60 feet underground since Dec. 6, shortly after hitting a steel pipe. In his email, Trepanier mentions but then downplays a project team member’s remark that it could take “one month” to resume drilling, without offering his own conjecture. Megaprojects are inherently uncertain enough that this sort of time estimate should be treated as an educated guess anyhow, rather than a fact.
Trepanier raises two other points that are more subtle, and more meaningful:
- He calls the wayward 8-inch-diameter steel pipe in front of the machine “a contributing factor,” which raises the ominous question of whether more problems lurk in the soil or in the machinery. “The overall cause won’t be known until our investigation is completed,” he said.
- Second, he notes that if the blockage can’t be removed through the vertical shafts that are being drilled this week, the shafts would be filled to build a deep concrete wall, to “create a safe environment” for workers. Such a wall would restrain loose soil and groundwater that would otherwise collapse into the cutting face during work there. In December, Chris Dixon, director of the Seattle Tunnel Partners (STP) contracting team, said such a barrier would take several weeks to build, even before sending a team in.
For the time being, the delay hasn’t busted the budget — but taxpayers could potentially take a hit if delays drag on. The project’s $2 billion plan includes a $40 million reserve for so-called “extraordinary interventions,” in which tunnel-trained divers remove surprise blockages or make emergency repairs to the cutter.
Beyond that, about $78 million in projectwide reserves remained untapped as of July, when drilling began, according to page 53 of this state Department of Transportation (DOT) report to the Federal Highway Administration. Project officials have acknowledged that some reserves likely will be drawn down, as STP and DOT sort out the costs and the blame. Citizens will recall that Transportation Secretary Lynn Peterson told lawmakers this week that the Highway 520 bridge project needs a $170 million infusion, after pontoon cracks and other woes consumed the $250 million reserve.
Here’s the text of Trepanier’s message: