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An evolving situation Shell official tells hearing about the events leading to the Kulluk grounding Alan Bailey Petroleum News
The nightmare began around mid-day on Dec. 27 when the towline parted between Shell’s anchor handling vessel, the Aiviq, and the Kulluk, the company’s floating drilling platform, leaving the Kulluk adrift in the Gulf of Alaska with a crew of 18 on board. The Aiviq had been towing the Kulluk from Dutch Harbor to a shipyard on the U.S. West Coast for winter maintenance, following the rig’s use by Shell for drilling in Alaska’s Beaufort Sea during the 2012 Arctic open water season.
The ensuing chain of events that led to the eventual grounding of the Kulluk on the shore of Sitkalidak Island, to the southeast of Kodiak Island, became the subject of a formal U.S. Coast Guard marine casualty investigation. As part of that investigation the Coast Guard is now conducting a hearing in Anchorage to gather testimony about the circumstances surrounding the grounding. Officials from the Bureau of Ocean Energy Management, the National Transportation Safety Board and the Marshall Islands are also participating in the hearing — the Kulluk is registered in the Marshall Islands.
Safety of crew On May 20 Norman Custard, Shell’s team lead for emergency response for the company’s Alaska program, told the hearing that his immediate concern on Dec. 27 had been the safety of the Kulluk’s crew. Custard, a retired Coast Guard officer with Coast Guard experience of marine emergency response, initially took command of the incident response for Shell. He told the hearing that he called a meeting of Shell’s incident management team and started appraising the situation.
Custard described how by 2 p.m. on Dec. 27, with a 20-foot swell at the incident location and with two Coast Guard helicopters available, the incident team started considering an evacuation plan for the Kulluk crew. But the Aiviq was able to stabilize the situation by successfully attaching an emergency towline to the Kulluk.
According to statements made during the hearing the original towline had parted at a shackle and the shackle was missing when the towline was later retrieved.
Vessels deployed Custard said that, although the Kulluk was back under tow by the evening of Dec. 27, he ordered the continuing deployment of vessels to provide assistance, given a forecast for approaching bad weather, plans for the evacuation of personnel and the possible need for some form of oil spill response. And by this time the Guardsman, a support vessel out of the port of Seward, and the Nanuq, Shell’s Arctic oil spill response vessel, were en route to the scene.
Initial optimism that the situation was under control proved short lived. Custard said that he was woken at 3:30 a.m. on Dec. 28 by a phone call informing him that the Aiviq was experiencing engine problems. A second call 30 minutes later told him that all of the Aiviq’s engines were out of action, although the vessel still had electrical power for operating its bow thrusters.
The Coast Guard cutter Alex Haley, which had been dispatched to the scene, succeeded in bringing the Aiviq and the Kulluk under tandem tow, although the towline subsequently broke and became tangled in one of the cutter’s propellers.
By 12:30 p.m. on Dec. 28 the incident management team had moved to an emergency operations center in the Marriott Hotel in downtown Anchorage, with a unified command involving the Coast Guard, Shell and Edison Chouest Offshore managing the incident — Edison Chouest owns the Aiviq. A representative of Noble Corp., the company operating the Kulluk, also attended unified command meetings, Custard said.
Evacuation request The Guardsman arrived on scene in the Gulf of Alaska and succeeded in hooking a line to the Aiviq and the Kulluk, in a tandem configuration. But, with the situation on the Kulluk very uncomfortable and people on the vessel becoming very tired, by 6 p.m. the unified command had requested the Coast Guard to evacuate the vessel. However, with the prospect of a nighttime evacuation and with the Kulluk “dancing around” in rough water, there remained some questions over the evacuation plan — despite the difficult conditions, an aerial evacuation using helicopters appeared safer than an evacuation by sea, Custard said. He explained that the risk associated with lowering lifeboats into the water from the heaving Kulluk was greater than the risks entailed in hoisting crew members to a helicopter.
And, although it might have been possible to keep people on the Kulluk, the response team wanted to evacuate the crew well before there was any possibility of a grounding, at which point large waves could have been breaking over the stranded vessel, Custard said.
However, the night evacuation did not prove practical — it was considered unacceptably dangerous. Moreover, by the morning of Dec. 29 the tow from the Guardsman had failed. The Kulluk dropped its survival anchor. And, with the wind slackening, the response team started looking for a safe harbor into which to move the Kulluk.
Tow re-established Meantime, Shell had been working with Edison Chouest to obtain replacement fuel injectors for the Aiviq’s engines (reports at the time of the incident suggested that the Aiviq may have suffered fuel contamination). The Coast Guard delivered the injectors to the vessel on the morning of Dec. 29 and by noon of that day three of the vessel’s four engines were running again. The Nanuq had arrived on scene earlier in the morning, so that by the afternoon both the Aiviq and the Nanuq were hooked up to the Kulluk. The plan at that point was to tow the Kulluk to a place of refuge near Kodiak, at the northeast end of Kodiak Island, Custard said.
Evacuation completed With the Kulluk under tow again, the vessel was fairly stable, enabling the evacuation of the vessel’s crew to finally proceed. The evacuation, a very safe operation using two Coast Guard helicopters, took about two hours and was complete by about 3:30 p.m., Custard said.
At this point the situation seemed to be looking up, with the Kulluk’s crew safe and the vessel in a stable tow. The plan was to move the vessel east for a time, to keep well clear of land, before turning north towards Kodiak, a transit that might take about two days to accomplish, Custard explained. And Shell continued to work with shipping contractors to bring more vessels to assist, including the tug Alert from Valdez.
But the optimism was short lived: In the afternoon of Dec. 30 the towlines from the Aiviq and the Nanuq both parted. Custard told the hearing that he did not know why the lines had broken. But with the weather deteriorating and the wind already blowing at 35 to 45 knots, re-establishing a tow became urgent. By 1 a.m. on Dec. 31, with the weather still worsening, the Alert and the Aiviq succeeded in attaching lines to the drilling rig. The response team decided to try to move the rig to shelter in Kiliuda Bay on the southeast side of Kodiak Island, Custard said.
Grounding But by 5:30 p.m. the Aiviq had lost its tow again. Although the Alert was still attached to the Kulluk, the vessels were being blown west at three to four knots in winds of 55 to 64 knots and 35- to 40-foot waves, with the Aiviq unable to re-attach its line. At this point it appeared inevitable that the Kulluk would run aground, Custard said. When the vessels reached a distance of three miles from shore, the unified command, worried about putting the Alert at risk, ordered the tug to release the Kulluk. Within half an hour the drilling vessel had grounded, Custard said.
The Coast Guard has said that it anticipates the Anchorage hearing continuing through the end of May. It may then be several months before the agency reports the results of its investigation. Dr. Barry Strauch, the National Transportation Safety Board representative in the hearing, said that the NTSB will make its own findings on the Kulluk incident.
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