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Stuck but intact Salvage team inspects Shell rig aground on shore of Sitkalidak Island By Alan Bailey Petroleum News
The Kulluk, Shell’s floating drilling platform, aground on the shore of Sitkalidak Island to the southeast of Kodiak Island, appears to be intact and stable, according to the team responding to the grounding incident. A five-member team of salvage experts visited the vessel for about three hours on Jan. 2. And a helicopter overflight of the grounding site on the same day spotted three of the Kulluk’s lifeboats near the stricken vessel, but no signs of any debris.
Shell has chartered Smit Salvage to head the salvage operation for the Kulluk. Shell presumably hopes to recover the vessel relatively intact, but at this stage the response team is unwilling to speculate on the means, timing and outcome of recovering the vessel.
However, an emergency towing system was placed on the Kulluk during the Jan. 2 inspection, U.S. Coast Guard Capt. Paul Mehler, the federal on-scene coordinator for the Kulluk response, explained during a press conference on the evening of Jan. 2.
“The plans for the Kulluk, once we’ve recovered it, will depend very much on the state of the vessel,” said Sean Churchfield, Shell’s incident commander.
On beach Steve Russell, the state on-scene coordinator, said that the Kulluk had run aground in water off a cobble beach with mixed sand and gravel. The beach is at the base of a 200-foot bluff.
Apparently the Kulluk was carrying 143,000 gallons of ultra-low sulfur diesel and roughly 12,000 gallons of other petroleum products, with much of the fuel acting as ballast, to stabilize the vessel in the sea. The fuel tanks are in the interior of the vessel, isolated from the vessel’s hull.
“I am encouraged by what we saw today and we are awaiting the salvage team’s assessment, to finalize plans to remove the potential for any (fuel) release,” Mehler said.
During a Jan. 1 press conference Russell said that the prime landowner in the area of the grounding is the Old Harbor village Native corporation. DEC says that three species listed under the Endangered Species Act may be present in the area, while wildlife known to frequent the area includes harbor seals.
Meantime, the chronicle of events leading to the grounding has emerged from a sequence of press releases, press conferences and statements to the media.
Maintenance needed Having demobilized the Kulluk from its 2012 drilling operations in the Beaufort Sea, Shell decided to move the drilling vessel from Dutch Harbor in the Aleutian Islands to the Seattle area of the U.S. West Coast for maintenance work, in preparation for a continuation of Arctic drilling in the summer of 2013. And, with the vessel not being self-propelled, Shell’s new anchor-handling vessel, the Aiviq, would tow the vessel for the three- to four-week voyage south. The Aiviq, launched early in 2012, has four engines, with a combined power of 21,776 horsepower. The Kulluk was equipped with one main towline, and a second emergency towline for use should the first line fail.
It was necessary to tow the Kulluk to the West Coast for maintenance, Shell spokesman Curtis Smith has told Petroleum News. Dutch Harbor is not a working shipyard and it would have been too logistically difficult to move the maintenance crew and materials to the Aleutian Islands port, Smith said.
Departed Dec. 21 The Aiviq and the Kulluk set out from Dutch Harbor on Dec. 21, following a weather-guided route that approximately paralleled the coastline. During a Jan. 1 press conference Churchfield said that the routing of the tow and the decision to depart Dutch Harbor relied on the weather forecasts at the time, with Shell setting a departure window but giving the Aiviq’s master discretion on when to leave. Once en route, the two vessels would travel at about four knots, Churchfield said.
Churchfield said that the U.S. Coast Guard had inspected the Kulluk in Dutch Harbor and that the tow company, warrantee surveyors and others had approved the tow plan.
Smith told Petroleum News that at the time of departure the weather forecast indicated a “favorable two-week window.”
“Our towing plan and the choice of the Aiviq had been positively reviewed by the Coast Guard,” Smith said.
But predicting the weather more than a few days ahead is notoriously difficult. By Christmas Day a winter storm was in the forecast for the seas to the south of Kodiak, in the area that by then the Aiviq and Kulluk were beginning to traverse.
Hawser parted Trouble started on Thursday, Dec. 27, when the towing hawser between the two vessels parted. Shell has not at this stage provided any insights into why the line broke — the company says that a diagnosis of the reason for the breakage will form part of a subsequent investigation into the Kulluk incident.
“The Aiviq has (previously) towed the Kulluk on a single towline for more than 4,000 miles, including in conditions similar to what we are seeing now in the Gulf of Alaska,” Smith told Petroleum News Jan.2.
Engine failure The initial problems with the towline escalated in the early hours of Dec. 28, at which time all four engines on the Aiviq failed when the Aiviq and the Kulluk were about 50 miles south of Kodiak. The engine failure appears to have resulted from fuel contamination, although that has yet to be confirmed. At about 8 a.m. the crew of the Aiviq succeeded in restoring power to one of the vessel’s engines, thus enabling the use of thrusters to maintain position.
Meantime, with the wind blowing at 40 mph, and with 35-foot seas and worsening sea conditions, the U.S. Coast Guard had dispatched the cutter Alex Haley to the scene to provide assistance. The Alex Haley succeeded in establishing a tandem tow with the Aiviq and the Kulluk. But at about 6:30 a.m. the towline parted and became tangled in the cutter’s port propeller, the Coast Guard said. The cutter subsequently returned to Kodiak for repairs.
The Coast Guard dispatched the cutter Hickory from Homer and the cutter Spar from Kodiak.
Vessels deployed Following the engine failure in the Aiviq, Shell started deploying vessels from its drilling fleet — the Guardsman, a support vessel, set out from Seward, while Shell’s oil spill response vessel, the Nanuq, also headed out.
The Guardsman arrived on scene south of Kodiak in the afternoon of Dec. 28 and succeeded in securing a towline to the Aiviq. In the evening, concerned about the safety of the 18 crew members on the Kulluk, Shell asked the Coast Guard to evacuate the crew. Early the following morning, the unified command authorized the Kulluk’s crew to drop its anchors off the coast of Kodiak, in an attempt to slow the drift of the vessel.
At 5:30 a.m. on Saturday, Dec. 29, the crew of the Guardsman reported that the towline from the Guardsman to the Aiviq had failed. But at 6:30 a.m. the Nanuq arrived and successfully connected a second towline.
Also on the Saturday morning, Coast Guard Jayhawk helicopters from Kodiak delivered engine parts to the Aiviq, to enable the Aiviq’s engines to be repaired. At 9:30 a.m. the Aiviq’s crew managed to restart a second engine.
Crew evacuated Later in the day, the Coast Guard announced that it had succeeded in evacuating all of the Kulluk’s crew by helicopter and that all four of the Aiviq’s engines were running again.
The Alaska Department of Environmental Conservation and a representative from the Kodiak Borough joined the unified command for the response to the incident.
During the morning of Sunday Dec. 30, with the severe weather continuing, the Kulluk remained under tow by the Aiviq and the Nanuq, by then about 20 miles south of Kodiak Island. Shell had also commissioned the tug Alert to join the response effort. The Alert, based in Valdez as part of Alyeska Pipeline Service Co.’s support fleet for the marine terminal at the southern end of the trans-Alaska oil pipeline, arrived on scene on the Sunday afternoon.
Adrift again But by 4:30 p.m. on that same day the towlines between the Kulluk and the Aiviq and the Nanuq had separated, leaving the Kulluk adrift again. At about 12:45 a.m. on Monday, Dec. 31, the Alert was able to attach to the 400-foot line that had become detached from the Aiviq. The Aiviq subsequently reconnected to the drilling rig. And, with the weather improving somewhat, there appeared to be an opportunity to better secure the rig before the next storm moved in.
“The sea state is actually significantly diminished but we anticipate that it’s going to build up again pretty quickly into a severe state,” Smith told Petroleum News at 9:30 a.m. on Dec. 31. “Right now unified command is considering options to further secure the vessel. That includes potentially new towlines, just for redundancy, and/or safe harbor further to the north.”
The Coast Guard briefly deployed technicians to the Kulluk to check the condition of the towlines on the vessel. But winds in excess of 60 mph were forecast for the evening.
Grounded At 4:30 p.m. the Aiviq lost its tow to the Kulluk. In the interests of safety, the towline from the Alert was released at 8:10 p.m. and before long the Kulluk drifted aground on the shore between the north end of Ocean Bay and Partition Cove on Sitkalidak Island.
As responsible party, Shell has said that it will pay for the cost of the response to the Kulluk incident, including costs incurred by the Coast Guard and the State of Alaska. Three people have been injured during the incident, but these injuries were minor in nature, Mehler said on Jan. 1.
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