An oil drilling rig belonging to Shell has run aground on an island in the Gulf of Alaska, providing what environmentalists say is further proof of the perils of Arctic oil drilling. The rig hit shore Monday night after crew members towing the vessel were forced to disconnect it amid stormy weather. Concerns mounted over a possible spill of diesel fuel and other contaminants on board. The rig’s crew had previously been evacuated. Marilyn Heiman, director of the Pew Environment Group’s U.S. Arctic Program, said the incident “calls into question our readiness to drill in such a remote and risky region. The Obama administration needs to impose Arctic-specific safety, training and spill response standards. Clearly we’re not there yet.”