XML 23 R12.htm IDEA: XBRL DOCUMENT v3.7.0.1
ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE
 6 Months Ended
Jun. 30, 2017
Asset Retirement Obligation Disclosure [Abstract]  
ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE
ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE
Accrued final capping, closure and post-closure costs include the current and non-current portion of costs associated with obligations for final capping, closure and post-closure of our landfills. We estimate our future final capping, closure and post-closure costs in order to determine the final capping, closure and post-closure expense per ton of waste placed into each landfill. The anticipated time frame for paying these costs varies based on the remaining useful life of each landfill, as well as the duration of the post-closure monitoring period.
A summary of the changes to accrued final capping, closure and post-closure liabilities follows:
 
Six Months Ended
June 30,
 
2017
 
2016
Beginning balance
$
44,207

 
$
41,041

Obligations incurred
1,310

 
1,143

Revisions in estimates (1)
9,598

 
(56
)
Accretion expense
1,939

 
1,782

Obligations settled (2)
(307
)
 
(432
)
Ending balance
$
56,747

 
$
43,478

 
(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 our Southbridge landfill associated with the Southbridge landfill closure. See Note 8, Commitments and Contingencies and Note 11, Other Items and Charges for disclosure regarding the matter.
(2)
Includes amounts that are being processed through accounts payable as a part of our disbursement cycle.