The Obama administration has launched a review of offshore oil drilling in the Arctic following a cascading series of blunders and mishaps by the oil giant Shell. Shell’s recent troubles culminated when its drill rig ran aground last week off the Alaskan coast, sparking concerns of a potential spill. Past problems have included safety and environmental violations on its vessels and the failure during a test of a device meant to control a gushing well. Government officials say the new 60-day review could potentially limit or halt Shell’s ambitions for Arctic drilling. The escalating issues have followed repeated warnings by environmental groups that Shell is unprepared for the harsh and dangerous conditions associated with Arctic drilling. Dan Howells of Greenpeace told The New York Times: “We’ve repeatedly been told Shell is the best in the business, and so we can only conclude after this series of mishaps that the best in the business is simply not good enough for the Arctic.” The Coast Guard has launched a separate investigation into the grounding of Shell’s drill rig last week.