24-7 work on Beacon Hill's Sound Transit tunnel

Contractors are inside Sound Transit's one-mile Beacon Hill tunnel around the clock, preparing the underground station for train testing by May, and a July grand opening for service from downtown Seattle to Tukwila.

Four elevators were recently installed, to carry passengers 165 feet to the boarding platforms, from the entrance along Beacon Avenue South at South Lander Street.

The tubular ceiling over the trackway was painted midnight blue, and multicolored sculptures, titled "Space Forms," will glow overhead. About 200 people were working intently Monday afternoon, sidestepping cords, supplies — and each other.

Sound Transit is spending millions to accelerate station construction and installation of power and signal systems to make up for earlier tunneling delays.

But overall, the $2.4 billion, 14-mile line is $125 million under budget and should open on schedule, if the last tunnel tasks go well.

Mike Lindblom, Seattle Times transportation reporter