““It's an unceremonious end to a big dig - excavating and building 8,300 linear feet of concrete-lined tunnels running from South of Market beneath Union Square and Chinatown to North Beach. But the excavation passed unnoticed by people on the surface, who didn't even feel vibrations. Big Alma and Mom Chung, each weighing 750 tons and stretching longer than a football field, even passed 7 feet beneath the BART tracks below Market Street without requiring the transit system to stop, or even slow, its trains.””
