Bertha’s Front End Lowered into Access PitSeattle Tunnel Partners (STP) lowered the front-end section of the tunneling machine named Bertha into the access pit Aug. 25 to continue work on the 2-mile-long tunnel beneath downtown Seattle.This section is the largest of four pieces that will be lowered into the pit for reassembly and includes the machine’s cutterhead, motors and the new main bearing assembly. Weighing in at 2,000 tons, the front end of Bertha was lowered 120 feet by a crane built by Mammoet, and is equipped with nearly 7 miles of steel cable and a lifting capability of 2,400
