The world’s largest tunnel boring machine is about to get to work in Seattle. Big Bertha, named for former city mayor Bertha Knight Landes, looks kind of like a giant, blue-tipped mechanical cigarette. It was built with the help of countries like Spain and Japan and is manned by a crew of 30 to 40 engineers. Big Bertha will dig up to 100 feet a day and build a massive tunnel under the city for a new freeway.

Greg Hauser, deputy project manager for contractor Seattle Tunnel Partners which is putting Big Bertha into action, joins Marketplace Tech host Ben Johnson to discuss.