By Steve Quinn
JUNEAU, Alaska, April 3 (Reuters) - Royal Dutch Shell ignored warnings about the dangers of a towing missionthat left a drillship grounded in the storm-tossed Gulf ofAlaska in 2012, in part to avoid paying millions of dollars instate property taxes, the U.S. Coast Guard said in a reportreleased on Thursday.
The Kulluk, having completed preliminary drilling on anexploration well in the Beaufort Sea, broke away from its towlines and support vessels attempting to regain control of thedrillship developed their own engine and mechanical problems, aShell official said last year.
The 152-page report, which came nearly a year after a U.S.Coast Guard hearing into the incident off Kodiak Island,concluded that Shell's towing plans "were not adequate for thewinter towing operation crossing the Gulf of Alaska."
It also said tax laws "influenced the decision" becauseShell believed the rig would be subject to taxation if it wereto stay in Alaska waters by Jan. 1, 2013.
The round drilling rig was towed by the Aiviq, acustom-built vessel operated by Edison Chouest Offshore.
"To be blunt, I believe that this length of tow, at thistime of year, in this location, with our current routingguarantees an ass kicking," Aiviq's tow master warned Shellearly in the tow, according to the U.S. Coast Guard's report.
Shell said it was reviewing the findings.
"We appreciate the thorough investigation and will take anyfindings seriously," the company said.
"Already, we have implemented lessons learned from ourinternal review of our 2012 operations. Those improvements willbe measured against the findings in the USCG report as well asrecommendations from the U.S. Department of (the) Interior."
The Kulluk was docked in Dutch Harbor along the AleutianIslands before setting out on the trip across the Gulf of Alaskato Washington state. None of the fuel on the rig spilled intothe water an no one was injured.
Shell has not resumed exploration in the Arctic.
A federal appeals court has ruled that the U.S. Departmentof Interior awarded Arctic drilling leases in 2008 withoutconsidering the range of potential environmental risks stemmingfrom oil drilling. (Editing by Paul Tait)