ASSET RETIREMENT OBLIGATIONS

12 Months Ended

Dec. 31, 2022

ASSET RETIREMENT OBLIGATIONS

ASSET RETIREMENT OBLIGATIONS

20.ASSET RETIREMENT OBLIGATIONS

The following table presents the activity affecting the asset retirement and mine closing liability:

	Year Ended December 31,
	2022		2021
	(in thousands)
Beginning balance	$	131,099	$	127,898
Accretion expense		3,731		3,688
Payments		(2,445)		(1,383)
Allocation of liability associated with mine development and change in assumptions		17,428		896
Ending balance	$	149,813	$	131,099

For the year ended December 31, 2022, the allocation of liability associated with mine development and change in assumptions increased by $17.4 million. The increase was largely attributable to higher cost assumptions as well as the expansion of refuse disposal facilities at certain mines.

For the year ended December 31, 2021, the allocation of liability associated with mine development and change in assumptions was immaterial.

The impact of discounting our estimated cash flows resulted in reducing the accrual for asset retirement obligations by $110.4 million and $98.3 million at December 31, 2022 and 2021, respectively. Estimated payments of asset retirement obligations as of December 31, 2022 are as follows:

Year Ended
December 31,	(in thousands)
2023	$	7,559
2024		4,936
2025		1,935
2026		1,569
2027		3,182
Thereafter		241,065
Aggregate undiscounted asset retirement obligations		260,246
Effect of discounting		(110,433)
Total asset retirement obligations		149,813
Less: current portion		(7,559)
Non-current asset retirement obligations	$	142,254

As of December 31, 2022 and 2021, we had approximately $174.3 million and $173.9 million, respectively, in surety bonds outstanding to secure the performance of our reclamation obligations.  

See Note 2 – Summary of Significant Accounting Policies for more information on our accounting policy for asset retirement obligations.