On a cloudy mid-March morning in 2015, two men set off from Valdes Island, B.C., in a small tugboat, pushing a barge loaded with construction equipment, a tank of diesel fuel and explosives. The materials belonged to a granite company, and the men were hauling them to the Sunshine Coast, where the company had a quarry.  

It was supposed to be a “run-of-the-mill” trip, according to John Spick, whose construction company owned the tugboat. It was anything but.