ASSET RETIREMENT OBLIGATIONS (Tables)

6 Months Ended

Jun. 30, 2018

ASSET RETIREMENT OBLIGATION

Schedule of Asset Retirement Obligations

Aggregate carrying amounts of asset retirement obligations are as follows (dollars in thousands):

	June 30,
	2018
Asset retirement obligations at beginning of period	$	56,855
Liabilities incurred		1,181
Liabilities settled		(1,975)
Accretion expense		2,223
Change in cash flow estimate		(456)
Total asset retirement obligations at end of period	$	57,828
Less current asset retirement obligations at end of period		(2,999)
Long-term asset retirement obligations at end of period	$	54,829