Protecting Arctic waters

Joint program researches aspects of responding to oil spill in ice-infested waters

Alan Bailey

Petroleum News

Worldwide interest in the petroleum potential of the Arctic seas has triggered a corresponding focus on the practicalities of responding to an oil spill, were disaster to strike an offshore oil operation. As part of the ramped-up interest in how to deal with an Arctic spill, a joint industry program coordinated by Norwegian research company SINTEF is engaged in a series of research projects covering most aspects of offshore Arctic spill response. The program’s objective is continuing development of tools and technologies for oil spill response in the Arctic and ice-infested waters.

AGIP KCO, Chevron, ConocoPhillips, Shell, Total, BP and Statoil are participating in the program with the expectation that its outcome will improve industry’s ability to protect Arctic environments from oil spills resulting from petroleum exploration, development, production and transportation.

Research results should also help decision making by responsible authorities, SINTEF program documents said.

The program consists of eight project areas, being carried out over a four-year period ending in 2009. They are designed to address key oil spill response issues and scenarios that program participants might have to deal with:

• The fate and behavior of oil spilled in Arctic conditions;

• The in-situ burning of oil in Arctic and ice-infested waters;

• The mechanical recovery of oil in Arctic and ice-infested waters;

• The use of chemical dispersants in Arctic and ice-infested waters;

• Monitoring and remote sensing of oil in or under ice;

• The preparation of a generic oil spill contingency plan;

• Field experiments at Svalbard, Norway, and in offshore ice-infested waters; and

• Program coordination, management, communication and publishing.

Initiated in Halifax

A plan for the program was presented at a workshop in Oslo in April 2006 and the program got under way in September 2006, Sørstrøm said. In addition to industry participants, there are a large number of potential collaborators, including the U.S. Minerals Management Service, Alaska Clean Seas and the Oil Spill Recovery Institute in Cordova. About five people from relevant organizations will ensure that the results of each project include the most up-to-date knowledge, Sørstrøm said.

A major part of the joint industry program consists of adapting existing systems for icy conditions. Equipment vendors have also been developing new concepts for recovering oil from ice-laden water and these concepts will be further tested, Sørstrøm said. In addition to research into the mechanical recovery of oil, the program includes testing of in-situ burning and the use of dispersants, Sørstrøm said.

“The first year has focused on laboratory tests of skimmers, dispersants and burning tests,” Sørstrøm said. “We have also carried out a long-term field experiment at Svalbard studying the weathering properties (of crude oil) as well as a window of opportunity for in-situ burning. Further we have carried out preliminary tests of some remote sensing and oil detecting systems.”

Sørstrøm said that most skimmers have been designed for open-water conditions, rather than for use in ice-laden water.

“Our tests so far have, however, proved that some of these systems may be developed further for operations in ice,” Sørstrøm said.

Adapting and developing systems

Because an oil spill response typically requires a combination of different techniques, the joint industry program is also investigating strategies and tactics for the Arctic, Sørstrøm said. A generic oil spill contingency plan developed in the program will accommodate a range of ice regimes encountered in the circum-polar area of interest.

The program holds two workshops per year, alternating between venues on the European and American continents. These workshops provide program participants with progress updates and also provide an opportunity to discuss oil spill response challenges in the regions where the workshops are held.

The first of these workshops was held in Svalbard in April 2007 and the second will be held in Anchorage on Oct. 15, following the Oct. 10 to 11 International Oil and Ice Workshop (some talks about the joint industry program have been scheduled as part of the international workshop).

Shell: proven techniques

For example, Shell sees in-situ burning of spilled oil as a particularly valuable part of its arsenal of response tactics. But, has in-situ burning actually been demonstrated to work in Arctic waters or in sea ice?

Absolutely, said Al Allen, Shell’s oil spill response consultant. Allen has amassed 40 years of experience in oil spill response and was at one time the manager of Absorb, the organization that later became Alaska Clean Seas, the North Slope oil spill response cooperative.

There have been dozens of situations where people have burned spilled oil in cold climates, and with ice and snow, Allen said. Some current research focuses on expanding knowledge of the limitations of burning, but the technique has been proven to work, he said.

“I’ve done it several times myself,” Allen said. “… When you see the results at high (recovery) efficiencies, you just come away knowing that this is fact. … I know it works. It can be a very effective tool, especially in cold climates.”

Allen was also involved in some tests of in-situ burning, done in sea ice at the West Dock at Prudhoe Bay, in the late 1970s and early 1980s.

“We did a series of tests over about a three-year period,” Allen said. “The spill sizes would vary from just a few gallons to five to 10 drums at a time.”

Skimmers

Sea ice tends to trap the oil on water surface, so that the oil becomes concentrated in a limited area, rather than spreading out to form an extremely thin layer over a wide expanse of open water, Allen said. Skimmers work best when the oil is concentrated rather than spread out. But brush skimmers and rope mop skimmers have been thoroughly tested in the recovery of limited pockets of oil.

“Rope mops (for example) — I’ve used them in a lot of actual spills in cold climates and you can get 95 percent (recovery) efficiencies,” Allen said. “… There are many situation where skimming in ice, handled properly, can be very efficient.”

In fact, the effectiveness of a particular skimming operation depends primarily on the knowledge and experience of the skimmer operators, Allen said.

Allen also emphasized that determining a spill response strategy in a particular situation involves evaluating tradeoffs between the likely recovery effectiveness and potential disadvantages in the use of different techniques such as burning or skimming in that situation.

—Alan Bailey