Via the Hill’s Briefing Room blog, it looks like the Architect of the Capitol is at last set to begin renovations on the infamous tunnel that runs between the U.S. Capitol complex and the Capitol Power Plant. The work, which involves digging a big pit to access the tunnel about a block away from the Capitol South Metro station, will cause traffic around the intersection of North Carolina Avenue and First Street SE will be detoured. You may recall that the tunnel, long in a state of crumbling disrepair, has been the subject of controversy for several years, after it was revealed in 2006 that a 10-man crew working inside it had been exposed to extremely high levels of asbestos.