Shell expands Arctic exploration plans

By Tim Bradner
Alaska Journal of Commerce – original article here

Shell now has a more expansive exploration strategy for the Beaufort and Chukchi seas than what the company had previously planned.

The company intended to file plans of exploration in early May with the Bureau of Ocean Energy Management, Regulation and Enforcement, or BOEMRE, for up to 10 exploration wells in the Beaufort and Chukchi seas in 2012 and 2013, a Shell spokesman said.

Two drillships would be used.

Previously Shell planned to use one drillship in 2012 in the Beaufort, with an expectation of drilling one to two wells.

“We believe the conversations we are having with regulators and government officials are more positive in view of the safeguards we have put in place, even prior to Macondo,” said Pete Slaiby, Shell’s Alaska vice president. “As a result, we are cautiously optimistic we will be allowed to pursue a multi-well drilling program in 2012 as we have always planned.”

Not all of the wells outlined in the new exploration plans will actually be drilled, company spokesman Curtis Smith said.

“We file for permits for more wells than will actually be drilled so there is flexibility in changing locations depending on new geologic information or ice conditions,” he said.

Smith said the plan is now to use two drillships, with a goal of drilling two wells per year in the Beaufort Sea and three wells per year in the Chukchi Sea, he said.

Each drilling vessel would provide backup for the other in drilling a relief well in the event of a blowout, Smith said.

In the Arctic, offshore drilling must be done during the summer when the ice recedes, creating open water. The exception to this is with wells in near-shore coastal waters, where the depth is shallow enough to build an artificial gravel island.

In the 1980s, drillship were used in several exploration wells farther from shore in the Beaufort Sea, and there also were offshore exploration wells drilled in the Chukchi Sea, including many by Shell in the early 1990s.

No commercial discoveries were made in the 1980s and 1990s, but oil and gas was found in both the Beaufort and Chukchi at locations that are now the prime targets for Shell’s renewed exploration.

The drillships planned for Shell’s 2012 and 2013 work are the Noble Discoverer, which is now under contract to Shell for Arctic exploration but is now being used elsewhere, and the Kulluk, a drilling vessel built for the Arctic that Shell owns.

The Kulluk is now in Dutch Harbor, where it is undergoing modification, Smith said.

The new more aggressive plan represents a change in Shell’s strategy. The company previously planned to drill one to two wells in the Beaufort Sea, with one drillship, in 2012.

Shell will have to file new applications for air quality permits for each ship and for each area of drilling.

An air quality permit for Shell’s existing plan of drilling one well in the Beaufort Sea with a single drillship, previously planned for 2011 or 2012, is still pending with the U.S. Environmental Protection Agency’s Region 10 office in Seattle.

EPA had previously issued the permit but it was appealed by environmental groups to EPA’s internal Environmental Appeals Board. The appeals board kicked the permit back to Region 10 last January with a request for modifications.

The Region 10 office has yet to resubmit the modified air permit back to the appeals board.

Smith could not comment on the status of the permit but said Shell “is having good conversations with EPA and we’re optimistic.”

The air quality permits are similar for both the Beaufort and Chukchi, Smith said. The effort to resolve issued with the initial permit should make it easier with permits that follow.

Shell holds 137 federal OCS leases in the Beaufort Sea and 275 leases in the Chukchi Sea. The company has spent over $3 billion so far in its efforts to secure leases, do environmental work and secure permits for exploring the leases. About $2.2 billion of that was spent in bonus bids paid to the federal government for the Chukchi Sea leases.

Tim Bradner can be reached at

tim.bradner@alaskajournal.com.

Beaufort Sea commercial fishing banned

CBC News Posted: Apr 15, 2011 5:32 PM CT – Original article here

Commercial fishing is off-limits in the Beaufort Sea, according to a new agreement between the federal government and the Inuvialuit people of the western Arctic.

An ulu, a traditional Inuit cutting tool, is seen on a table with Arctic char in Iqaluit in this 2009 photo. Like in the eastern Arctic, char is fished by the Inuvialuit people in the Beaufort Sea.
An ulu, a traditional Inuit cutting tool, is seen on a table with Arctic char in Iqaluit in this 2009 photo. Like in the eastern Arctic, char is fished by the Inuvialuit people in the Beaufort Sea. (Jonathan Hayward/Canadian Press)

The memorandum of understanding, which both parties signed Friday in Inuvik, N.W.T., is the first step towards a comprehensive ocean management plan in the Beaufort Sea.

The agreement prohibits any new licences from being issued for commercial fishing in the Beaufort Sea at least until the management plan is developed and implemented — a process that could take years.

Commercial fishing does not usually happen in the Beaufort Sea, but melting sea ice have opened up Arctic waterways to more fishing and commercial traffic.

Preventing a fishing rush

For many years, Arctic char and other fish species in the Beaufort Sea and other northern waterways had been protected by thick layers of sea ice that were dangerous for fishing and other marine vessels.

‘We don’t want to wake up some morning … and find a big, rusty Korean fishing boat offshore.’—Burton Ayles

But the Northwest Passage has become more ice-free recently, which has led to more cruise ships, sailboats and commercial shipping and fishing vessels coming north.

The Beaufort Sea fishing ban is being put in place before there is a rush to create a new commercial fishery, according to federal and Inuvialuit officials.

“We don’t want to wake up some morning in [Tuktoyaktuk, N.W.T.] and find a big, rusty Korean fishing boat offshore,” said fisheries scientist Burton Ayles, a member of the Fisheries Joint Management Committee, which consists of federal and Inuvialuit representatives.

With fish stocks in steep decline around the world, Ayles said Inuvialuit and others living near the Beaufort Sea do not want the region to be overfished.

Temporary commercial fishing permits that were issued in the Beaufort Sea over the past 10 years have not worked out well, Ayles said.

“They didn’t always report back properly on what they were harvesting,” he said.

Fragile ecosystem

Nellie Cournoyea, chair of the Inuvialuit Regional Corp., said the Beaufort Sea ecosystem is too fragile to accommodate large boats with fishing nets.

The Canadian Coast Guard icebreaker Louis S. St-Laurent makes its way through the ice in Baffin Bay in 2008. Arctic waterways have increasingly become ice-free in recent years, opening them up to more marine traffic.
The Canadian Coast Guard icebreaker Louis S. St-Laurent makes its way through the ice in Baffin Bay in 2008. Arctic waterways have increasingly become ice-free in recent years, opening them up to more marine traffic. (Jonathan Hayward/Canadian Press)

Cournoyea said not much is known about fish populations in the area, but people in the area do know that fish is a vital food source for other marine species.

“There’s a cautionary approach to this because it all has to come into balance,” she said.

“You wouldn’t want to create a fishery that would take away from that food stock of the whales or the seals or the other species that live offshore.”

Frank Pokiak of the Inuvialuit Game Council said people in the region would rather see Inuvialuit people participating in small-scale traditional fisheries than large-scale commercial fisheries.

“They’re willing to keep the doors open for Inuvialuit beneficiaries to do small-scale fisheries,” he said. “I know some people, at this time right now, they do harvest some of the fish species for selling … dry fish and things like that.”

Russia Embraces Offshore Arctic Drilling

By ANDREW E. KRAMER and CLIFFORD KRAUSS Published: February 15, 2011 in the New York Times – Original article here

The Prirazlomnaya oil platform was brought to the Arctic seaport of Murmansk, 906 miles north of Moscow, to be adjusted.

MOSCOW — The Arctic Ocean is a forbidding place for oil drillers. But that is not stopping Russia from jumping in — or Western oil companies from eagerly following.

Russia, where onshore oil reserves are slowly dwindling, last month signed an Arctic exploration deal with the British petroleum giant BP, whose offshore drilling prospects in the United States were dimmed by the Gulf of Mexico disaster last year. Other Western oil companies, recognizing Moscow’s openness to new ocean drilling, are now having similar discussions with Russia.

New oil from Russia could prove vital to world supplies in coming decades, now that it has surpassed Saudi Arabia as the world’s biggest oil producer, and as long as global demand for oil continues to rise.

But as the offshore Russian efforts proceed, the oil companies will be venturing where other big countries ringing the Arctic Ocean — most notably the United States and Canada — have been wary of letting oil field development proceed, for both safety and environmental reasons.

After the BP accident in the gulf last year highlighted the consequences of a catastrophic ocean spill, American and Canadian regulators focused on the special challenges in the Arctic.

The ice pack and icebergs pose various threats to drilling rigs and crews. And if oil were spilled in the winter, cleanup would take place in the total darkness that engulfs the region during those months.

Earlier this month, Royal Dutch Shell postponed plans for drilling off Alaska’s Arctic coast, as the company continued to face hurdles from wary Washington regulators.

The Russians, who control far more prospective drilling area in the Arctic Ocean than the United States and Canada combined, take a far different view.

As its Siberian oil fields mature, daily output in Russia, without new development, could be reduced by nearly a million barrels by the year 2035, according to the International Energy Agency. With its economy dependent on oil and gas, which make up about 60 percent of all exports, Russia sees little choice but to go offshore — using foreign partners to provide expertise and share the billions of dollars in development costs.

And if anything, the gulf disaster encouraged Russia to push ahead with BP as its first partner. In the view of Russia’s prime minister, Vladimir V. Putin, BP is the safest company to hire for offshore work today, having learned its lesson in the gulf.

“One beaten man is worth two unbeaten men,” Mr. Putin said, citing a Russian proverb, after BP signed its Arctic deal with Rosneft, the Russian state-owned oil company. The joint venture calls for the companies to explore three sections in the Kara Sea, an icebound coastal backwater north of central Russia.

The BP agreement touched off little public reaction in Russia, in part because the environmental movement is weak but also because opposition politicians have no way to block or hinder the process.

The Arctic holds one-fifth of the world’s undiscovered, recoverable oil and natural gas, the United States Geological Survey estimates. According to a 2009 report by the Energy Department, 43 of the 61 significant Arctic oil and gas fields are in Russia. The Russian side of the Arctic is particularly rich in natural gas, while the North American side is richer in oil.

While the United States and Canada balk, other countries are clearing Arctic space for the industry. Norway, which last year settled a territorial dispute with Russia, is preparing to open new Arctic areas for drilling.

Last year Greenland, which became semi-autonomous from Denmark in 2009, allowed Cairn Energy to do some preliminary drilling. Cairn, a Scottish company, is planning four more wells this year, while Exxon MobilChevron and Shell are also expected to drill in the area over the next few years.

But of the five countries with Arctic Ocean coastline, Russia has the most at stake in exploring and developing the region.

“Russia is one of the fundamental building blocks in world oil supply,” said Daniel Yergin, the oil historian and chairman of IHS Cambridge Energy Research Associates. “It has a critical role in the global energy balance. The Arctic will be one of the critical factors in determining how much oil Russia is producing in 15 years and exporting to the rest of the world.”

Following the template of the BP deal, Rosneft is negotiating joint venture agreements with other major oil companies shut out of North America and intent on exploring the Arctic continental shelf off Russia’s northern coast. That includes Shell, its chief executive said last month. Rosneft’s chief executive, Eduard Y. Khudainatov, said other foreign oil company representatives were lining up outside his office these days.

Artur N. Chilingarov, a polar explorer, has embodied Moscow’s sweeping Arctic ambitions ever since he rode in a minisubmarine and placed a Russian flag on the bottom of the ocean under the North Pole, claiming it for Russia, in a 2007 expedition.

“The future is on the shelf,” Mr. Chilingarov, a member of Russia’s Parliament, the Duma, said in an interview. “We already pumped the land dry.”

Russia has been a dominant Arctic oil power since the Soviet Union began making important discoveries in the land-based Tazovskoye field on the shore of the Ob Bay in Siberia in 1962. The United States was not far behind with the discovery of the shallow-water Prudhoe Bay field in Alaska five years later.

What is new is the move offshore.

The waters of the Arctic are particularly perilous for drilling because of the extreme cold, long periods of darkness, dense fogs and hurricane-strength winds. Pervasive ice cover for eight to nine months out of the year can block relief ships in case of a blowout. And, as environmentalists note, whales, polar bears and other species depend on the region’s fragile habitats.

Such concerns have blocked new drilling in Alaska’s Arctic waters since 2003, despite a steep decline in oil production in the state and intensive lobbying by oil companies.

In Canada, Arctic offshore drilling is delayed as the National Energy Board is reviewing its regulations after the gulf spill.

Mr. Chilingarov placed a Russian flag on the bottom of the ocean under the North Pole, claiming the area for Russia, in a 2007 polar expedition.

But Russia is pressing ahead. The central decision opening the Russian Arctic easily passed Parliament in 2008, as an amendment to a law on subsoil resources. It allowed the ministry of natural resources to transfer offshore blocks to state-controlled oil companies in a no-bid process that does not involve detailed environmental reviews.

Until recently Russia regarded the Kara Sea, where BP and Rosneft intend to drill, as primarily an icy dump. For years, the Soviet navy released nuclear waste into the sea, including several spent submarine reactors that were dropped overboard at undisclosed locations.

Rosneft executives say their exploration drilling will not stir up radiation.

But in any case, Mr. Chilingarov, the advocate for Russian polar claims, said a little radiation was nothing to worry about. He said that his son was born on Novaya Zemlya, an Arctic testing site for nuclear weapons during the cold war, and is now “a bit taller than me.”

“In small doses,” Mr. Chilingarov said, “radiation is good for growth.”

Andrew E. Kramer reported from Moscow and Clifford Krauss from Houston.

This article has been revised to reflect the following correction:

Correction: February 19, 2011
A chart on Wednesday with an article about Russia’s eagerness to drill for oil in the Arctic Ocean gave an incorrect unit of measurement for estimates of natural gas reserves in the region. The shaded areas in the chart are believed to hold more than 100 trillion cubic feet of natural gas, not cubic tons. The unit of measurement was correct in an online version of the chart, available at nytimes.com/business.

BP Hopes For Alaska Arctic Oil Production In Beaufort Sea In 2013

BECKY BOHRER   02/ 1/11 Huffington Post, original article here

JUNEAU, Alaska — BP PLC estimates that it could begin producing oil off Alaska’s coast in 2013, despite the fact that construction of the massive Liberty rig has been suspended indefinitely.

BP said last fall that it was suspending construction of the rig to review its engineering and design plans, and ensure the Liberty project can be done safely.

The unusual project calls for using a manmade gravel island in the Beaufort Sea as a drilling base. A rig would drill horizontally for six to eight miles to tap what BP estimates is a 100-million-barrel reserve of recoverable oil.

BP Alaska spokesman Steve Rinehart says the project review is progressing but he couldn’t say when it would be complete or when construction would resume.

Shell gets conditional OK for Beaufort exploratory drilling

I am sorry, but Hornorkesteret and Anchorage Daily News do not see eye to eye on this one. See also earlier post about “unconventional ‘tight’ shales, sands, carbonates and hydrocarbon ‘source’ rocks.”
Anchorage Daily News: Our view: Good call
Original article here

Shell Alaska’s plans to drill an exploratory well just offshore in the Beaufort Sea this summer is a go — pending another safety review by federal regulators.

Interior Secretary Ken Salazar said offshore Arctic exploration would proceed “with utmost caution.” Close scrutiny of Shell’s plans and performance should be no damper on 2011 exploration plans.

Shell scaled back its original 2011 program, leaving disputed Chukchi Sea development to be resolved in court to focus on the Beaufort project. The more modest enterprise will give the company, regulators and North Slope leaders a chance to narrow their focus and make sure everything is done right.

While it’s still a little tentative, the Obama administration’s endorsement reflects the decision it made about Alaska development before the Deepwater Horizon disaster in April. That decision was to nix exploration near the rich salmon fishery of Bristol Bay, but to explore and develop with care in the Arctic.

That made sense then and still does.

Rear Adm. Christopher Clovis, commander of the Coast Guard in Alaska, said last month that he has confidence in Shell’s exploration plans for 2011. He said actual production — which is the goal of exploration, after all — presents more problems. But there’s time to address those.

Let Shell go to work in 2011 to explore for oil — and also restore faith in the industry’s ability and will to do it right, to tap Alaska’s oil and gas treasure while abiding by the highest and environmental and safety standards on the planet.

That’s the challenge. We need the oil. We need the jobs. And we need to provide them while protecting the Arctic environment and its communities.

BOTTOM LINE: Feds’ conditional blessing of Shell’s Beaufort exploration is good news.

Arctic Drilling Poses Untold Risks, Study Concludes

The idiocy continues.
Hornfar

Original article here in The New York Times “Green” blog

By LESLIE KAUFMAN

An image of a an oil-spill response vessel from a Shell commercial promoting Arctic drilling.

Green: Science

Now that the moratorium on deep-sea oil and gas drilling has been lifted by the Obama administration, the battle for the Arctic is heating up again.

The suspension of deep-sea drilling was of course a reaction to the disastrous blowout in the Gulf of Mexico that gushed from April to July, producing the biggest offshore oil spill in the nation’s history. The moratorium was lifted last month, about six weeks before a Nov. 30 expiration date.

As soon as it was lifted, my colleague Cliff Krauss reported last week, Royal Dutch Shell began lobbying eagerly to get final approval for its long-delayed plans for exploratory drilling in Alaska’s Beaufort Sea. The petro-giant is paying for national advertising as part of a campaign to convince the public and the government that it is taking safety precautions that would prevent the kind of catastrophe that unfolded in the gulf from happening in the Arctic.

Yet the Arctic is well known to be more fragile ecologically than the gulf. And on Thursday, the Pew Environment Group released a detailed report brimming with charts and maps that explores the question of how well the government and industry would be equipped to deal with a blowout and spill there. The report concludes, not so well. And here are some word-for-word highlights on why:

  • The Arctic Ocean is a unique operating environment, and the characteristics of the Arctic OCS [outer continental shelf] — its remote location, extreme climate and dynamic sea ice—exacerbate the risks and consequences of oil spills while complicating cleanup.
  • Oil spill contingency plans often underestimate the probability and consequence of catastrophic blowouts, particularly for frontier offshore drilling in the U.S. Arctic Ocean.
  • The impact of an oil well blowout in the U.S. Arctic Ocean could devastate an already stressed ecosystem, and there is very little baseline science upon which to anticipate the impact or estimate damage.
  • Oil spill cleanup technologies and systems are unproved in the Arctic Ocean, and recent laboratory and field trials (including the Joint Industry Project) have evaluated only discrete technologies under controlled conditions.
  • Certain environmental and weather conditions would preclude an oil spill response in the Arctic Ocean, yet an Arctic spill response gap is not incorporated into existing oil spill contingency plans or risk evaluations.

So the researchers concluded that far more study is needed of the Arctic marine ecosystem. Modeling should be devised to project the trajectory of oil flow in sea ice conditions should a spill occur, they added.

And deployment exercises should be conducted to determine how effective a spill response would be in such a remote, sparsely populated region “before introduction of new offshore oil spill risks,” the report said. (The study includes a detailed critique of Shell’s planning scenarios in the Chukchi and Beaufort Seas.)

In other words, the study’s message is that the Arctic is not ready for such deep-sea drilling operations.

Asked about the Pew report’s conclusions, a Shell spokeswoman, Kelly op de Weegh, said in an e-mail that the company had “taken extraordinary steps to compensate for the harsh conditions we expect to encounter in the Arctic, and that is evident in all aspects of our program, including ice management, a commitment to oil spill response and new baseline science.”

“Our Arctic exploration plan has been scrutinized by regulators, stakeholders and the courts, and we look forward to demonstrating once again that we can operate safely and responsibly in the Arctic,” she added.

The study’s conclusion was also disputed by lawmakers who support the drilling. “I disagree with Pew’s insistence on an unspecified moratorium on Arctic development, because the perfect set of conditions simply never occurs,” Senator Mark Begich, Democrat of Alaska, said in a statement. “I’ll continue to push the Obama administration for responsible Arctic development now to help meet America’s energy, national and economic security.”

Meeting the challenges of arctic offshore pipelines and subsea systems

Arctic drilling – obviously not a good idea. As we burn more oil and melt more of the polar icecaps, ironically, more and more oil and gas becomes available. It seems like we won’t be able to stop this madness before we have dug our own graves and fallen in. Prepare for gigantic arctic oil spills that are too dangerous to clean up.

Beware of slanted new-speak like “unique challenges”, “acceptable levels of risk” and “high technology readiness level”. This is obviously madness – what is an acceptable risk level in our precious arctic?

Hornfar.

—–

Original article here, at offshore-mag.com.

Duane DeGeer

Published: Nov 1, 2010

INTECSEA

Editor’s note: This is the second in a series about the unique challenges encountered when attempting to design, engineer, install, and operate offshore oil and gas facilities in the Arctic. The next installment will be on engineering arctic topsides facilities.

Production pipelines and flowlines in the North American Arctic have begun to move offshore in the past decade, as engineering companies draw upon a trove of environmental, geotechnical, and operational data accumulated during the past 30-plus years. During this time, engineers have been able to develop new design processes, introduce pioneering construction methods, and develop first-in-class subsea solutions to deal with the extreme loading conditions posed by the region’s ice and sub-freezing temperatures.

Arctic pipeline design proficiency has progressed steadily since the spike in oil prices brought on by the 1973 Arab Oil Embargo and, coupled with discovery of giant Prudhoe Bay field on Alaska’s North Slope, provided the economic and strategic impetus to design and construct the first large-scale arctic pipeline project, the Trans Alaska Pipeline System (TAPS), commissioned in 1977. TAPS engineers developed many practical solutions to a range of technical, logistical, and environmental challenges stemming mainly from permafrost thaw potential and low environmental temperatures in the difficult, isolated terrain.

Still in operation, TAPS has provided experience in operating long-distance (800 mi/1,287 km), large-diameter (48 in./122 cm) transmission lines in the unique arctic environment, and has allowed other proposed gas transmission lines, such as the Mackenzie Gas Pipeline and trans-Alaska gas pipeline, to proceed with a higher level of design, construction, and operational confidence. Tempering these technical and strategic successes, however, is the realization that the huge financial investment required – to conduct initial feasibility studies and front-end engineering to determine the viability of a proposed arctic development; to design and install facilities that can recover resources from remote arctic locations; and to transport production to distant markets – means that only the very largest, high-volume discoveries are destined to be developed.

The Arctic remains among the high-cost production areas in the world because the unique environment magnifies the complex problems that must be analyzed and solved when planning a grass roots field development in the region. Not only is inordinate advanced planning required; the designs of facilities, installation strategies and methods, and maintenance and operating programs must be developed on essentially a project-by-project basis. Yet, the growing body of knowledge about arctic conditions coupled with improvements in material behavior, advances in analytical techniques, wider acceptance of a strain-based design philosophy, and, finally, implementation of a reliability-based approach to the operation of arctic pipeline systems, enable some of these offshore prospects to be developed.

The first subsea arctic oil production pipeline in the North American Arctic was installed in 2000 by BP in about 37 ft (11 m) of water to connect Northstar production facilities on Seal Island, about 6 mi (9.7 km) offshore Alaska in the Beaufort Sea. Twin specially designed, 10-in. (25 ½-cm) diameter steel pipelines comprise the heart of the Northstar system, which was buried 7-to-10 ft below the sea floor to avoid ice scour and is equipped with three leak-detection systems. Northstar crude is transported overland to TAPS through an elevated pipeline.

The second subsea arctic production pipeline to be installed is at the Oooguruk field, about 6 mi offshore Alaska in the Beaufort Sea near the Colville River delta. Installed in the winter of early 2007, the Oooguruk flowline system consists of a three-phase, 12-in. x 16-in. (30 ½- x 41-cm) pipe-in-pipe (PIP) production flowline bundled with an 8-in. (20-cm) water-injection line, 6-in. (15-cm) gas lift/injection line, 2-in. (5-cm) diesel fuel line, and power and communications cables. The location of the Oooguruk flowline system, in less than seven feet of water at the mouth of the eastern distributary of the largest river drainage system on the Alaskan North Slope, presented unique loading conditions and thermal interactions, imposing additional design requirements to integrate with solutions for more conventional arctic conditions. The Oooguruk production flowline represents the first application of PIP flowline technology offshore Alaska.

More recently, the Nikaitchuq flowline bundle was installed and is scheduled to begin operation in early 2011.

Offshore arctic challenges

Aside from standard operating pressure containment, the primary loading conditions to be considered in the design and construction of offshore arctic pipeline and subsea systems include ice gouging or scour, upheaval buckling, permafrost thaw settlement and/or frost heave, and strudel scour.

Ice gouging or scour is the most significant and most unpredictable environmental loading condition influencing arctic offshore pipeline design. The accepted solution to protect a subsea pipeline from this threat is to bury the line deeper than the maximum gouge depth expected over the design life of the pipeline. For pipeline systems, research into safe burial depth finds that soil below the scouring keel of the ice will deform, imposing high shear and bending loads on the buried line. More recently, research to reduce overall uncertainty associated with ice keel interactions with the seabed has been directed towards understanding ice keel gouging and integrating these data with historical seabed mapping data. Upheaval buckling potential, caused by differences between installation and operating temperatures, also can be influenced by careful selection of burial depth. Subsea systems must also be protected from the extremely high ice loads. Off the east coast of Canada, glory holes are excavated on the sea floor so drill centers and subsea equipment can sit below the seabed elevation, thereby offering protection from ice impact.

Permafrost thaw settlement and frost heave can impose long-term displacement-controlled bending on a subsea pipeline, and can contribute to a pipeline being strained outside the elastic limit into the plastic region of the material deformation; thus the need for strain-based design. These unique arctic loads can be present along a buried subsea pipeline route, especially near shore where shallow permafrost is likely to exist; and also onshore, where a buried line may traverse continuous or discontinuous permafrost.

Strudel scour can occur in early spring if seasonal river outflows precede the thawing of winter sea ice, with the result that water flows on top of the sea ice. If river water atop sea ice flows into depressions or cracks in the ice, it can penetrate the ice cover and initiate a powerful downward jet of water that can erode the sea floor. Erosion by this strudel scouring may expose long sections of a buried subsea pipeline.

Burial depths sufficient to guard against ice gouging might be adequate protection from strudel scour, and some designers consider the probability of strudel scour at the location of a subsea pipeline to be quite low. However, if heat escapes during operation of a subsea flowline in shallow water and warms the sea water above the line, that fugitive heat dissipation might prevent the ice above the line from becoming as thick during winter. In the spring, such artificially thin ice could be susceptible to early cracking and, in turn, strudel scour.

Pipelines, flowlines, and subsea systems must operate within an acceptable thermal regime, and provide the necessary containment and monitoring to ensure acceptable levels of risk. For example, visual monitoring is not always a reliable way to detect strudel scours or pipeline exposure locations, and the pipeline itself must not exceed certain allowable strains. Using PIP flowlines on both the Oooguruk and Nikaitchuq bundles allows for double containment and an annulus in which insulation (vacuum or other) can be used. In addition, a thermal monitoring system can detect operational thermal changes as well as thermal changes from pipe exposed to cooler seawater, possibly signaling an issue with upheaval buckling or strudel scour. In these cases, analysis and design of the flowline system must consider these design/operation aspects in an integrated manner.

Looking ahead

As our understanding of the unique loading conditions of the arctic develops, as subsea equipment reliability and performance advances, and as our computational expertise in flow assurance and system operability improves, other arctic development concepts are becoming possible. Subsea tiebacks now exceed 100 km (62 mi) in length, offering possible arctic subsea completions without a permanent host structure. All-electric subsea technology, full subsea separation and water re-injection, seafloor chemical storage and injection, and gas re-injection technical advancements have made possible the concept of full subsea completions in the Arctic. Depending on reservoir conditions, some development options are at a high technology readiness level, some even field-proven in non-arctic regions.

Advancements in trenching and dredging methods and equipment make it possible to consider fast, efficient pipeline trenching operations and glory hole excavations in as much as 150 m (492 ft) water depth. Development of cost-effective mechanical protection of subsea equipment also progresses, providing an economical compromise between glory hole dredging and structural resistance to iceberg scour.

Arctic offshore pipeline design, subsea equipment technology, subsea system operating practices, and understanding of arctic environmental conditions continues to advance and, as a result, the options available for Arctic and cold regions field development grow. Ice and metocean conditions, seabed bathymetry, soil conditions, presence of permafrost, reservoir conditions and layout, and development location all play important roles in selecting an arctic production facility. These factors must be considered integrally, and the design philosophy must provide the framework necessary to consider all aspects of Arctic development in one overall life-cycle design system. This, in turn, will optimize levels of risk and ensure consistent personnel and environmental safety over the lifetime of an Arctic field development.

References

1. Paulin, Michael J., Nixon, Derrick, Lanan, Glenn A., and McShane, Brian, “Environmental Loadings & Geotechnical Considerations for the Northstar Offshore Pipelines,” August 2001, Proceedings of the 16th International Conference on Port and Ocean Engineering under Arctic Conditions.

2. Lanan, Glenn A., Cowin, Todd G., Hazen, Beez, Maguire, David H., Hall, J.D., and Perry, Conrad, “Oooguruk Offshore Arctic Flowline Design and Construction,” (OTC 19353), May 2008, Offshore Technology Conference.

3. INTECSEA Quarterly Journal, 2nd Q., 2010

About the author

Duane DeGeer serves currently as manager of Arctic Projects at INTECSEA and is based at the company’s head office in Houston. DeGeer has more than 24 years of experience in a variety of engineering activities and program initiatives relating to marine and onshore pipelines, downhole tubulars, arctic pipeline and structural research, riser integrity, and numerous large scale experimental programs. He has been responsible for a number of technical developmental initiatives over the years, and has managed specialized engineering departments focused on pipeline engineering and structural integrity.