
10.	ACCRUED EXPENSES AND OTHER LONG-TERM LIABILITIES

Accrued expenses and other long-term liabilities consisted of the following as of December 31 (in millions):



	Accrued Expenses				Other Long-Term Liabilities
	2011		2010		2011		2010
Defined benefit plan liabilities (see Note 14)	$	37	$	54	$	796	$	636
Wage and other employee-related liabilities	259		172		79		85
Uncertain income tax position liabilities (see Note 16)	—		—		337		343
Other tax liabilities	—		—		103		106
Environmental liabilities	39		40		235		228
Accrued interest expense	108		116		—		—
Derivative liabilities	25		39		—		—
Insurance liabilities	13		13		79		80
Asset retirement obligations	6		20		81		81
Other	108		136		171		208
Accrued expenses and other long-term liabilities	$	595	$	590	$	1,881	$	1,767

Environmental Liabilities

Changes in our environmental liabilities were as follows (in millions):



	Year Ended December 31,
	2011			2010			2009
Balance as of beginning of year	$	268		$	279		$	297
Pembroke Acquisition	30			—			—
Additions to liability	18			50			21
Reductions to liability	(5		)	(21		)	(5		)
Payments, net of third-party recoveries	(35		)	(42		)	(40		)
Foreign currency translation	(2		)	2			6
Balance as of end of year	$	274		$	268		$	279

In connection with our various acquisitions, we assumed certain environmental liabilities including, but not limited to, certain remediation obligations, site restoration costs, and certain liabilities relating to soil and groundwater remediation. There were no significant environmental liabilities assumed in connection with the Meraux Acquisition.

Asset Retirement Obligations

We have asset retirement obligations with respect to certain of our refinery assets due to various legal obligations to clean and/or dispose of various component parts of each refinery at the time they are retired. However, these component parts can be used for extended and indeterminate periods of time as long as they are properly maintained and/or upgraded. It is our practice and current intent to maintain our refinery assets and continue making improvements to those assets based on technological advances. As a result, we believe that our refineries have indeterminate lives for purposes of estimating asset retirement obligations because dates or ranges of dates upon which we would retire refinery assets cannot reasonably be estimated at this time. When a date or range of dates can reasonably be estimated for the retirement of any component part of a refinery, we estimate the cost of performing the retirement activities and record a liability for the fair value of that cost using established present value techniques.

We also have asset retirement obligations for the removal of underground storage tanks (USTs) for refined products at owned and leased retail locations. There is no legal obligation to remove USTs while they remain in service. However, environmental laws require that unused USTs be removed within certain periods of time after the USTs no longer remain in service, usually one to two years depending on the jurisdiction in which the USTs are located. We have estimated that USTs at our owned retail locations will not remain in service after 25 years of use and that we will have an obligation to remove those USTs at that time. For our leased retail locations, our lease agreements generally require that we remove certain improvements, primarily USTs and signage, upon termination of the lease. While our lease agreements typically contain options for multiple renewal periods, we have not assumed that such leases will be renewed for purposes of estimating our obligation to remove USTs and signage.

Changes in our asset retirement obligations were as follows (in millions).



	Year Ended December 31,
	2011			2010			2009
Balance as of beginning of year	$	101		$	179		$	72
Additions to accrual	4			3			98
Reductions to accrual	—			(34		)	—
Accretion expense	4			7			14
Settlements	(22		)	(54		)	(5		)
Balance as of end of year	$	87		$	101		$	179

There are no assets that are legally restricted for purposes of settling our asset retirement obligations.

Other

Other tax liabilities relate primarily to contingent liabilities for transactional tax claims that are both probable and reasonably estimable.