Thursday, October 7, 2010

The Challenges of Oil Spill Response in the Arctic

This draft report from the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling describes some of the difficulties of spill response in the Arctic.

In the staff’s view, response challenges in the Arctic are important for the Commission to consider in its recommendations for the future of offshore drilling. This paper provides background information regarding the status of offshore drilling in Arctic waters, identifies problems with responding to oil spills in Arctic waters, and highlights areas for further Commission inquiry with respect to Arctic drilling. The two locations of offshore drilling in the Arctic, the Beaufort Sea and the Chukchi Sea, present different drilling conditions and response issues.

The Beaufort Sea drilling sites are situated on man-made gravel islands located two to fifteen miles offshore, in water depths up to approximately 100 feet.2 They are often linked to onshore facilities and are close to land and shoreline resources. The majority of the construction of the offshore gravel islands, however, needs to be completed during the winter ice season when an ice road exists between the site and the mainland.

The locations of drilling interest in the Chukchi Sea are much further offshore and, consequently, much less accessible. This area had until recently generated less interest from industry as a result of its lack of shoreline infrastructure and the consequent heightened cost of drilling. The current applications from the Shell Oil Company and StatOil are for seismic exploration and exploratory drilling at least sixty miles off the coast that would take place during the open water season from July to October.

These differences in environmental conditions and drilling proposals mean that spill response in the Beaufort Sea would potentially be more straightforward than spill response in the Chukchi. The Beaufort region has more developed and proximate infrastructure, so access to a spill area might be easier. However, the Beaufort drilling sites are closer to both the sensitive shoreline and the areas traversed by bowhead whales and whale hunters.

A spill or blowout in the Chukchi Sea area would be more difficult to access, let alone contain and clean up. Although Shell has pre-positioned assets dedicated to potential spill response in the Chukchi Sea, bringing any assets, both the pre-staged equipment and any additional resources brought from elsewhere, to bear on a spill in the Arctic would be more difficult than in the Gulf of Mexico. And once the winter freeze occurs, any spill would be impossible to access for purposes of response. On the other hand, any spill in the Chukchi Sea would be far from coastal resources, and oil trapped beneath sea ice would be unlikely to spread into marine ecosystems until the ice began to melt.

The Arctic areas also stand in contrast with the Gulf of Mexico in terms of the issues posed by deepwater drilling. The Deepwater Horizon containment efforts were complicated immensely by the depth of the wellhead and the high well pressures encountered at the Macondo well. Wells in both the Chukchi and the Beaufort Seas would be in far shallower water, which could make it easier to contain a blowout or riser leak. Shell asserts that well pressures in the Chukchi and Beaufort Seas would be approximately one third to one half of the pressures faced by BP at the Macondo well.

Finally, although wells in the Chukchi would be similar to the Macondo well in terms of distance from shore, the human uses of the shoreline of the Gulf Coast are much more expansive than the human uses of the North Slope Coast.

The contrasts between these regions and between open water and ice conditions affect the nature of spill response and spill response planning. Many of the issues highlighted in this paper apply to both the Beaufort and the Chukchi Seas, but the different conditions should be kept in mind.

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