Loose ceiling bolts have been found in the tunnel that runs alongside the one in Yamanashi Prefecture that collapsed Dec. 1 and left nine people dead, sources said Saturday.
The bolts anchor ceiling boards in the Chuo Expressway tunnel with lanes heading away from Tokyo. The bolts do not appear to pose an immediate risk of the ceiling’s collapse, the sources said.
The collapsed tunnel was for the traffic lanes heading toward Tokyo. Together they are called the Sasago Tunnel, and the undamaged side was closed when its sister tunnel collapsed.
In the wake of the accident, the expressway operator, Central Nippon Expressway Co., or NEXCO-Central, carried out emergency checks on the other tunnel from Monday through Thursday, according to the company and the transport ministry. The loose bolts were found during the emergency checks.
The highway operator conducted regular checks on the two tunnels in September, but hammering tests during the checks did not cover the entire length of the tunnels.
The operator will begin work Sunday to remove ceiling boards from the undamaged tunnel and wants to reopen it to traffic in both directions by the end of this month.
Traffic through the Sasago Tunnel averaged 40,000 to 50,000 vehicles a day. Nearby communities are requesting that it be reopened as soon as possible because they are being overwhelmed by detour traffic.
“We decided to reopen at an early date while ensuring safety, as the closure’s negative effects are spreading,” said the expressway operator’s senior managing officer, Akira Hirose.