By Yereth Rosen
ANCHORAGE, Alaska | Thu Mar 28, 2013 2:51am EDT
(Reuters) - A fourth government probe is under way into Royal Dutch Shell's mishap-prone 2012 Alaska drilling season, this time for possible violations of international marine environmental rules, a U.S. Coast Guard official said on Wednesday.
The Coast Guard has asked federal prosecutors to consider taking action on possible violations of the International Convention for the Prevention of Pollution from Ships (MARPOL) committed in the operations of Shell's Kulluk drillship, said Rear Admiral Thomas Ostebo, head of the Coast Guard in Alaska.
Shell, which had planned to drill up to five wells offshore Alaska in 2012 and a similar number this year, has previously said it will pause its Alaska operations to regroup due to complications faced in the harsh northern environment, but it expects to resume drilling next year.
Ostebo said he had commissioned one investigation already launched into the December 31 grounding of the Kulluk and that the Coast Guard has forwarded findings of safety and environmental violations on the Noble Discoverer, Shell's other Alaska drillship, to U.S. prosecutors for possible enforcement action.
"Last week, I also referred a separate Kulluk investigation into potential MARPOL violations from 2012 to the Department of Justice for their review and potential follow-on action," Ostebo said at a field hearing conven