SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2025

As of December 31, 2025 and 2024, the Company had total marketable securities as follows (in thousands):


	December 31, 2025		December 31, 2024
Commercial paper	$	3,988	$	4,035
Corporate notes and bonds	1,601		—
Total cash equivalents	5,589		4,035



Commercial paper	9,942		17,489
Corporate notes and bonds	117,421		85,145
Total marketable securities	127,363		102,634
Total	$	132,952	$	106,669

Schedule of Activity in Allowance for Doubtful Accounts

The following table reflects the activity in the allowance for doubtful accounts and revenue allowance (in thousands):


	Allowance for Doubtful Accounts						Revenue Allowance
	2025		2024		2023		2025		2024		2023
Balance at January 1,	$	22,908	$	22,568	$	24,659	$	24,334	$	19,641	$	20,594
Additions charged to earnings	8,079		8,129		5,956		45,021		48,301		46,467
Deductions from reserves, net of recoveries	(9,831)		(7,789)		(8,047)		(54,520)		(43,608)		(47,420)
Balance at December 31,	$	21,156	$	22,908	$	22,568	$	14,835	$	24,334	$	19,641

Schedule of Activity in Revenue Allowance

The following table reflects the activity in the allowance for doubtful accounts and revenue allowance (in thousands):


	Allowance for Doubtful Accounts						Revenue Allowance
	2025		2024		2023		2025		2024		2023
Balance at January 1,	$	22,908	$	22,568	$	24,659	$	24,334	$	19,641	$	20,594
Additions charged to earnings	8,079		8,129		5,956		45,021		48,301		46,467
Deductions from reserves, net of recoveries	(9,831)		(7,789)		(8,047)		(54,520)		(43,608)		(47,420)
Balance at December 31,	$	21,156	$	22,908	$	22,568	$	14,835	$	24,334	$	19,641

Schedule of Asset Classification and Estimated Useful Life

The Company depreciates and amortizes the capitalized cost of these assets, using the straight-line method as follows:


Asset Classification						Estimated Useful Life
Buildings and building improvements
Buildings						20-42 years
Leasehold and building improvements						2-45 years
Vehicles						2-15 years
Equipment
Capitalized software and computer equipment						3-5 years
Containers and railcars						8-16 years
All other equipment						4-30 years
Furniture and fixtures						5-8 years

Property, plant and equipment consisted of the following (in thousands):


	December 31, 2025		December 31, 2024
Land	$	193,438	$	184,191
Asset retirement costs (non-landfill)	40,232		38,705
Landfill assets	278,700		258,138
Buildings and improvements (1)	753,404		719,439

Vehicles (2)	1,583,387		1,455,530
Equipment (3)	2,652,027		2,600,085

Construction in progress	90,182		70,305
	5,591,370		5,326,393
Less - accumulated depreciation and amortization	3,050,303		2,878,452
Total property, plant and equipment, net	$	2,541,067	$	2,447,941

___________________________________

(1) Balances inclusive of gross ROU assets classified as finance leases of $8.0 million in both periods.

(2) Balances inclusive of gross ROU assets classified as finance leases of $294.2 million and $230.5 million, respectively.

(3) Balances inclusive of gross ROU assets classified as finance leases of $17.4 million and $9.2 million, respectively.

Schedule of Active Landfill Sites

As of December 31, 2025, the Company had eight active landfill sites (including the Company's non-commercial landfill), which have estimated remaining lives (based on anticipated waste volumes and the remaining highly probable airspace) as follows:


Facility Name	Location	Remaining Lives (Years)	Permitted Remaining Highly Probable Airspace (cubic yards) (in thousands)
Buttonwillow	California	17	4,597
Deer Trail	Colorado	16	1,271
Grassy Mountain	Utah	36	4,133
Kimball	Nebraska	21	496
Lambton	Ontario, Canada	41	3,983
Lone Mountain	Oklahoma	52	13,528
Ryley	Alberta, Canada	47	5,475
Sawyer	North Dakota	59	3,136
			36,619

Schedule of Remaining Highly Probable Airspace

The following table presents the remaining highly probable airspace from January 1, 2024 through December 31, 2025 (in thousands of cubic yards):


	2025	2024
Remaining capacity, beginning of year	26,951	27,753
Changes in highly probable airspace, net	10,909	—

Consumed	(1,241)	(802)
Remaining capacity, end of year	36,619	26,951

CLEAN HARBORS INC 10-K