News blog

Arctic oil drilling begins in Chukchi Sea

On 9 September, oil company Shell began drilling off the coast of Alaska in what is the first offshore exploratory arctic drilling in the Chukchi Sea for more than 20 years (see Oil exploration ramps up in US Arctic).

Shell has received permission to drill three exploratory wells in the Chukchi Sea, but can only drill in oil-bearing zones until 24 September to give adequate time to drill a relief well, if required, before the threat of encroaching sea ice would make it impossible. Shell has requested an extension of almost three weeks, as they expect that sea ice movement in the area will be later than usual this year — on 26 August, Arctic sea ice reached its lowest extent ever recorded.

The first pilot test hole, on which drilling began Sunday, is about 22cm wide and is intended to reach an oil reservoir at a depth of more than 2,400 metres. Drilling however is currently only allowed to 427m, as permission to penetrate oil-bearing layers is contingent on an oil-spill barge and equipment arriving at the site, which is anticipated to take several more weeks.

Sea ice frequently covers the area by mid-November, and last year an early November storm pounded the Chukchi coast with hurricane force winds that ripped roofs off houses and blew out windows in a nearby village onshore. Environmental organizations have expressed concern about sea ice movements and inclement weather late in the season, when drilling a relief well would be difficult or impossible.

Regulatory approval has also been granted for Shell to drill two exploratory wells in the Beaufort Sea, where sea ice restrictions come into effect more than a month later than in the Chukchi, but drilling has been halted there since 25 August until the traditional subsistence whale hunt is finished.

Unless an extension is granted, only the upper portions of wells in both the Chukchi and Beaufort Sea are likely to be completed this year, with drilling to resume in July 2013. Shell has announced its intention to complete ten test wells in the Chukchi and Beaufort by the end of the 2013 drilling season.

Comments

Comments are closed.