The oil giant Shell has admitted that an oil drilling rig that ran aground late last year left Alaskan waters in a bid to avoid paying millions in taxes. The Kulluk was trying to pass through the Gulf of Alaska when it was pushed aground by a severe winter storm. The Coast Guard had to rescue the ship’s crew, and the incident helped spark a federal review of offshore drilling in the Arctic. Testifying to the Coast Guard over the weekend, Sean Churchfield, operations manager for Royal Dutch Shell in Alaska, said the decision to leave Alaska’s Dutch Harbor before the storm hit was “driven by the economic factors.” Shell would reportedly have had to pay more than $6 million in taxes had it stayed through January 1.