The mysterious object blocking the world's largest tunnel boring machine in Seattle, is finally identified -- it's an 8-inch-diameter steel pipe. The Washington State Department of Transportation said Friday that the steel pipe that stopped "Bertha," as the borer is nicknamed, on Dec. 6 is a 119-foot-long well casing installed in 2002 to study groundwater movement under downtown Seattle. “We need to investigate further to see if there are other factors that could have contributed to the blockage,” Matt Preedy, a deputy administrator on the project, said in a statement. The mystery had intrigued Seattleites, with some speculating that an old locomotive or steamship boiler might have been buried in the fill. The mystery had intrigued Seattleites, with some speculating that an old locomotive or steamship boiler might have been buried in the fill. “Our focus right now is on resuming tunneling as quickly and safely as possible,” Preedy said.
