FINAL CAPPING, CLOSURE AND POST-CLOSURE COSTS (Tables)

12 Months Ended

Dec. 31, 2019

Asset Retirement Obligation Disclosure [Abstract]

Changes to Accrued Capping, Closure and Post-Closure Liabilities

The changes to accrued final capping, closure and post-closure liabilities are as follows:

	Fiscal Year Ended December 31,
	2019		2018
Beginning balance	$	73,075	$	62,290
Obligations incurred	2,549		3,713
Revisions in estimates (1)	(1,538)		5,095
Accretion expense	6,227		5,556
Obligations settled (2)	(8,386)		(3,579)
Ending balance	$	71,927	$	73,075

(1)Relates to changes in estimates and assumptions concerning anticipated waste flow, cost and timing of future final capping, closure and post-closure activities at certain landfills, including the Subtitle D landfill in Southbridge, Massachusetts ("Southbridge Landfill"), as well as changes to expansion airspace at other landfills. See Note 17, Other Items and Charges for disclosure regarding Southbridge Landfill.

(2)Includes amounts paid and amounts that are being processed through accounts payable as a part of our disbursement cycle.