ASSET RETIREMENT OBLIGATIONS

6 Months Ended

Jun. 30, 2021

ASSET RETIREMENT OBLIGATIONS [Abstract]

Note 9: Asset Retirement Obligations

Asset retirement obligations (AROs) are legal obligations associated with the retirement of long-lived assets resulting from the acquisition, construction, development and/or normal use of the underlying assets, including legal obligations for land reclamation at both owned properties and mineral leases. Recognition of a liability for an ARO is required in the period in which it is incurred at its estimated fair value. The associated asset retirement costs are capitalized as part of the carrying amount of the underlying asset and depreciated over the estimated useful life of the asset. The liability is accreted through charges to operating expenses. If the ARO is settled for other than the carrying amount of the liability, we recognize a gain or loss on settlement.

ARO operating costs related to accretion of the liabilities and depreciation of the assets are as follows:



	Three Months Ended		Six Months Ended
	June 30		June 30
in thousands	2021	2020	2021	2020
ARO Operating Costs
Accretion	$ 3,259	$ 3,247	$ 6,455	$ 6,155
Depreciation	2,664	2,063	5,325	3,899
Total	$ 5,923	$ 5,310	$ 11,780	$ 10,054

ARO operating costs are reported in cost of revenues. AROs are reported within other noncurrent liabilities in our accompanying Condensed Consolidated Balance Sheets.

Reconciliations of the carrying amounts of our AROs are as follows:



	Three Months Ended		Six Months Ended
	June 30		June 30
in thousands	2021	2020	2021	2020
Asset Retirement Obligations
Balance at beginning of period	$ 285,401	$ 263,445	$ 283,163	$ 210,323
Liabilities incurred	0	0	938	0
Liabilities settled	(2,260)	(3,354)	(4,953)	(8,588)
Accretion expense	3,259	3,247	6,455	6,155
Revisions, net	35	410	832	55,858
Balance at end of period	$ 286,435	$ 263,748	$ 286,435	$ 263,748

ARO revisions during the first six months of 2020 primarily include increases in estimated costs at two aggregates locations, including reclamation activities required under a development agreement at an aggregates site on owned property in Southern California. The reclamation required under the development agreement will result in the restoration of previously mined property to conditions suitable for retail and commercial development.