PLANT, PIPELINE AND EQUIPMENT (Tables)

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Schedule of Plant, Pipeline and Equipment

Plant, pipeline and equipment include the following at December 31:
	2020		2019
	(thousands of dollars)
Platinum catalyst	$	1,580	$	1,580
Catalyst	4,325		4,095
Land	5,428		5,428
Plant, pipeline and equipment	270,149		258,651
Construction in progress	6,422		5,052
Total plant, pipeline and equipment	287,904		274,806
Less accumulated depreciation	(100,800)		(85,887)
Net plant, pipeline and equipment	$	187,104	$	188,919