and i said, "casselton?" i said, "i can't believe that." >> reporter: what did it tell you about what's going on, on the rails here in north dakota? >> well, it tells me and i think everybody the same thing. you know, what if that happened, you know, in... in a city or even in the middle of a town? you know, it could be really catastrophic. >> reporter: as mayor mcconnell says, his town dodged a bullet. but months earlier, a community in canada wasn't nearly so lucky. on july 6, 2013, a similar train, also loaded with crude from the bakken shale formation, derailed and exploded in the center of lac megantic, quebec, killing 47 people and destroying much of the town center. seven years ago, u.s. railways carried just 9,500 carloads of crude each year. but today, as huge amounts of oil are produced in states like north dakota far from traditional pipeline infrastructure, that figure has jumped to half a million. and after a handful of oil train derailments already in 2015 regulators are taking notice enacting a