Massachusetts Transportation Secretary Jeff Mullan says Boston's Big Dig tunnels are safe following an incident last month in which a 110-pound light fixture dropped from a tunnel roof. Mullan said his agency inspected the 23,000 lights throughout the tunnel system and found that a mounting panel corroded by winter weather and de-icing treatment gave way in the Feb. 8 incident. Mullan said one fixture was replaced and 3,000 others repaired.

Related Summaries