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Alaska a surprise, says Joey Hall Pioneer’s Oooguruk project manager learns ‘new lesson’ in Alaska, brings valuable deepwater experience to offshore Arctic Ray Tyson For Petroleum News
Joey Hall assumed managing Pioneer Natural Resources’ $500 million Oooguruk project offshore Alaska’s North Slope would be a walk in the park compared to the challenges he faced working on Pioneer’s deepwater program in the Gulf of Mexico.
“I thought I’d go up to Alaska and catch a few fish, kick my feet back and have a nice easy project,” Hall recalled. “Well, I’ve learned a new lesson. The offshore Arctic is equally and even more challenging in many ways than deepwater.”
However, Hall discovered that “many of the things we learned in deepwater we’re now applying in the offshore Arctic. I think in the years to come you’re going to be hearing a lot more about the things … going on in the offshore Arctic.”
As Hall and Intec Engineering representatives John Stearns and Glenn Lanan pointed out during a panel discussion May 2 at the Offshore Technology Conference in Houston, Texas, one huge lesson learned from the deepwater is the tricky business of constructing and installing sub-sea pipelines in a safe and reliable manner.
Pioneer’s Oooguruk oil pipeline is being designed by Intec and will be the second export pipeline ever installed offshore Arctic. The first was installed as part of BP’s Northstar oil project east of Oooguruk and north of Prudhoe Bay. Like the Northstar line, Oooguruk’s will be buried in a trench to protect against sea ice.
“Important to the pipeline design is the affect on sub-sea soil,” said John Stearns, vice-president of Intec’s Marine Pipeline Systems division.
Oooguruk’s “three-phase pipe bundle system,” stretching 5.7 miles from shore to a six-acre man-made gravel island supporting a drilling rig, 40 to 60 production and injection wells and related facilities, “is really the most challenging part of this project,” Pioneer’s Hall said. “This is the thing that keeps me up at night.”
The Oooguruk line is actually two pipelines in one, with the main oil line wrapped in a protective outer shell that would contain any leaks from the primary line. The entire line will then be wrapped in insulation to keep heat from the oil from melting the surrounding permafrost.
In deepwater, this pipeline system is traditionally used for its insulating value, but for the shallow water Oooguruk pipeline the mission is actually two-fold.
“First and most important is leak detection,” Hall said. “The Arctic is a very pristine environment and we have to at all costs protect the environment. The other thing it does is that if we did have a leak in the inner pipe, it provides containment. Cleaning up a spill in the Arctic is extremely challenging.”
The pipeline bundle also includes separate lines for water and gas injection, plus a diesel line to support drilling operations on the island, which rests in just 4.5 feet of water. The entire package will be buried in a six-foot trench.
“Because it is shallow water and every winter the ice freezes to the bottom, if the pipeline puts out too much heat it can actually melt some of the ice on the top,” Intec’s Stearns said. “While this may not in itself hurt the pipeline, it is disruptive to the environment and can cause weak spots in the ice.”
Island completed in April The six-acre island was completed in late April, requiring three months and 22,000 dump truck loads of gravel to finish the job. Winter ice roads were used to haul the gravel to the site.
“Building the island was quite a feat in itself,” Hall said, noting that the island rises 23 feet from the ocean floor and was designed to withstand impacts from shifting ice.
Hall said the gravel island is expected to “subside” or settle about four feet, a process he said would normally take about two and a half years. To speed up the process, 3,000 holes were drilled on the island to a depth of around 50 feet, allowing the underlying sand to be manipulated by forcing water downhole, rather than off to the sides if allowed to settle naturally. “We hope to accelerate the subsiding to about nine months,” he said.
Oooguruk is expected to come on-stream in late 2007 or early 2008, pumping at peak rates of 15,000 to 20,000 barrels of oil per day. From a shore base, the oil will be transported via an over land pipeline 2.4 miles for processing at the ConocoPhillips-operated Kuparuk production facility.
Nabors’ 19-E will be modified Nabors’ 19-E drilling rig, located on the North Slope, will undergo “significant modifications” this summer and then be moved to the island next winter, Hall said, adding that 19-E will remain on the island during Oooguruk’s entire “three-year drilling cycle.”
Hall said the project is on schedule but cautioned that “like everywhere else, we’re dealing with manpower issues up on the North Slope. The workforce is aging and there aren’t any younger people taking their place.”
Although 25 percent of the world’s undiscovered reserves are thought to be in the Arctic, capturing them offshore will be expensive, requiring various technologies to fit the vast array of Arctic conditions around the globe, noted Lanan, Intec’s pipeline engineering discipline manager.
Lanan said hydrocarbon targets above the Arctic Circle, such as the Barents Sea offshore Norway and Russia, are free of ice year round. In contrast, the high Arctic region near the pole is constantly locked in ice and offers “no opportunity to move floating equipment to do your construction work.”
“The Caspian Sea is well south of the Arctic Circle, but it has a lot of ice in the winter time that would affect developments in Russia and Kazakhstan,” Lanan said.
More interest at $70 Because of the expense, there is obviously more industry interest in the Arctic when oil is $70 per barrel versus $10 per barrel, Lanan said. “Having been in offshore Arctic pipelines for over 25 years, you can see the interest goes up and down with the price of oil. We’re in a high period now.”
He said offshore Arctic “has several interesting features,” most notably the difficulty in transporting workers, equipment and supplies to remote construction sites, as well as extracting the oil and moving it to market. “Pipelines are actually a very key part of that,” he added.
“In terms of the environment, the climate is quite cold with total darkness in the winter time,” he said. “The key issue is sea ice. The soils on the bottom have permafrost, which has implications when you try to chain things to it. It can cause ice heaves. The ice moves and imposes large forces on structures that are on the surface and actually can have significant impacts on the sea bed.”
Sub-sea installations also are subject to strudel-scour in shallow water and ice-gouging in deeper water.
In the summer, when there may be no ice, “you’ve got the waves to contend with,” Lanan said. “And you can get very significant wave activity in these areas.”
Despite the huge expense and technical challenges, offshore Arctic provides “quite an opportunity” to develop new technologies, Lanan said.
Deepwater technology similar He added: “One of the things we can draw on is very similar to the development of technology for deepwater: how that advanced over the past decade, the progression of how deepwater is defined and the technology applied for development of structures — pipelines, transportation systems and choice of equipment.”
Lanan said the future of Arctic development hinges on how industry applies existing and new technologies to such things as extended reach drilling, sub-sea developments and “where you can avoid having structures coming to the surface.”
He said that from man-made gravel islands such as Oooguruk and Northstar, offshore development in the Arctic could evolve into steel and concrete-based structures, and ultimately to floating structures and sub-sea field development, as the hunt for oil and gas moves into deeper waters.
Another potential stumbling block as industry moves into deepwater Arctic is the Jones Act, which prohibits the use of non-U.S.-flag vessels from operating between U.S ports, Lanan said, noting that currently there are no U.S.-flag vessels capable of operating in ice-clogged environments.
“There are limited vessels available in the world that can do this,” he said. “And if you have to have a U.S.-flag vessel that has a major impact on both the cost and schedule of a lot of the project planning.”
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