Abstract
In the winter of 2009-2010, seven ice tracking beacons were deployed in two separate arrays in the ExxonMobil/Imperial Oil lease known as Ajurak in the Canadian sector of the Beaufort Sea. The Ajurak lease lies 100 to 160 km north of the Mackenzie Delta, in water depths ranging from 60 m to 600 m. The purpose of the deployment was to assess the fate of a hypothetical under-ice well blow-out. The purpose of this paper is to describe the planning process prior to field operations including a Health, Safety and Environmental (HSE) plan and a Safe Operations Plan (SOP), the deployment, the data analysis and the resulting drift tracks and velocity statistics. Satellite imagery was used to monitor ice conditions prior to deployment to assess the competence of the ice cover, and also to chart the development of land fast ice throughout the winter. An array of beacons deployed in early December followed the expected pattern of westerly drift with periods of rapid drift and occasional reversals and stationary periods. The leading beacon passed Point Barrow, 750 km west of Ajurak, in 4 months. By July, this beacon had drifted well into the Chukchi Sea, a total of 1370 km from its deployment location. The second array of beacons, deployed in mid-January, remained within the Canadian Beaufort Sea.
The longest surviving beacon in this array drifted about 200 km west of Ajurak and stopped reporting in late April. Drift of this array appeared to be impeded by the development of large seaward extensions in the land fast ice adjacent to the Alaskan coast, as well as a series of onshore movements of the polar pack ice.
