By CBC News Ottawa, November 11, 2016
A senior engineer for the consortium building Ottawa's $2-billion light rail line says they'll be looking into the cause of an industrial incident that required three tunnel workers to be escorted out by emergency crews on Thursday afternoon.
Peter Lauch, technical director with the Rideau Transit Group, told CBC News that a steel "cage" designed to provide stability and strength came loose from the tunnel wall as workers were applying shotcrete — essentially, sprayable concrete used to reinforce structures.
http://www.cbc.ca/news/canada/ottawa/rideau-transit-group-lrt-tunnel-accident-1.3846642