Asset retirement obligations (“ARO”)

9 Months Ended

Sep. 30, 2012

Asset Retirement Obligation Disclosure [Abstract]

Asset retirement obligations (“ARO”)

Asset retirement obligations (“ARO”)

Our asset retirement obligations consist primarily of costs associated with the disposal of spent pot liner used in the reduction cells of our domestic facilities.

The reconciliation of the changes in the asset retirement obligations is presented below:

	Nine months ended September 30,			Year ended December 31, 2011
Beginning balance, ARO liability	$	15,171		$	14,274
Additional ARO liability incurred	874			1,110
ARO liabilities settled	(1,035		)	(1,315		)
Accretion expense	875			1,102
Ending balance, ARO liability	$	15,885		$	15,171

Certain conditional AROs related to the disposal costs of fixed assets at our primary aluminum facilities have not been recorded because they have an indeterminate settlement date. These conditional AROs will be initially recognized in the period in which sufficient information exists to estimate their fair value.