PROPERTY, PLANT AND EQUIPMENT

3 Months Ended

Mar. 31, 2022

PROPERTY, PLANT AND EQUIPMENT.

PROPERTY, PLANT AND EQUIPMENT

3. PROPERTY, PLANT AND EQUIPMENT

	Net Book Value of Property Plant and Equipment at March 31, 2022
(thousands of dollars)	Alabama		Corporate		Total
Mineral rights and properties	$	8,972	$	—	$	8,972
Other property, plant and equipment		4,525		28		4,553
Construction in progress		18,138		—		18,138
Total	$	31,635	$	28	$	31,663

	Net Book Value of Property Plant and Equipment at December 31, 2021
(thousands of dollars)	Alabama		Corporate		Total
Mineral rights and properties	$	8,972	$	—	$	8,972
Other property, plant and equipment		4,462		28		4,490
Construction in progress		1,017		—		1,017
Total	$	14,451	$	28	$	14,479

Construction in Progress

Construction in progress represents assets that are not ready for service or are in the construction stage. Assets are depreciated once they are placed in service.

During the three months ended March 31, 2022, the manufacturing of equipment, for which the Company made cash deposits of $2.7 million as of December 31, 2022, began.  As such, the deposit as of December 31, 2021 is now reflected as construction in progress as of March 31, 2022.

Impairment of Property, Plant and Equipment

The Company reviews and evaluates its long-lived assets for impairment on an annual basis or more frequently when events or changes in circumstances indicate that the related carrying amounts may not be recoverable. For the three months ended March 31, 2022 and March 31, 2021, no events or changes in circumstance are believed to have impacted recoverability of the Company’s long-lived assets. Accordingly, it was determined that no interim impairment was necessary.