| ☒ | QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 | |||||||||||||
| FOR THE QUARTERLY PERIOD ENDED | SEPTEMBER 30, 2026 | |||||||||||||
| OR | ||||||||||||||
| ☐ | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 | |||||||||||||

| Massachusetts | 04-2997780 | |||||||||||||||||||||||||
| (State or Other Jurisdiction of Incorporation or Organization) | (IRS Employer Identification No.) | |||||||||||||||||||||||||
| 42 Longwater Drive | Norwell | MA | 02061-9149 | |||||||||||||||||||||||
| (Address of Principal Executive Offices) | (Zip Code) | |||||||||||||||||||||||||
| Title of each class | Trading Symbol | Name of each exchange on which registered | ||||||||||||
| Common Stock, $0.01 par value | CLH | New York Stock Exchange | ||||||||||||
| Large accelerated filer | ☒ | Accelerated filer | ☐ | ||||||||||||||
| Non-accelerated filer | ☐ | Smaller reporting company | ☐ | ||||||||||||||
| Emerging growth company | ☐ | ||||||||||||||||
| Page No. | |||||
| September 30, 2026 | December 31, 2025 | ||||||||||
| ASSETS | (unaudited) | ||||||||||
| Current assets: | |||||||||||
| Cash and cash equivalents | $ | 423,544 | $ | 826,315 | |||||||
| Short-term marketable securities | 93,010 | 127,363 | |||||||||
Accounts receivable, net of allowances aggregating $51,627 and $35,991, respectively | 1,273,770 | 1,044,137 | |||||||||
| Unbilled accounts receivable | 218,442 | 160,888 | |||||||||
| Inventories and supplies | 407,922 | 372,088 | |||||||||
| Prepaid expenses and other current assets | 96,346 | 116,452 | |||||||||
| Total current assets | 2,513,034 | 2,647,243 | |||||||||
| Property, plant and equipment, net | 2,757,283 | 2,541,067 | |||||||||
| Other assets: | |||||||||||
| Operating lease right-of-use assets | 254,827 | 255,084 | |||||||||
| Goodwill | 1,843,273 | 1,479,050 | |||||||||
| Permits and other intangibles, net | 866,755 | 653,027 | |||||||||
| Other long-term assets | 48,433 | 48,585 | |||||||||
| Total other assets | 3,013,288 | 2,435,746 | |||||||||
| Total assets | $ | 8,283,605 | $ | 7,624,056 | |||||||
| LIABILITIES AND STOCKHOLDERS’ EQUITY | |||||||||||
| Current liabilities: | |||||||||||
| Current portion of long-term debt | $ | 12,600 | $ | 12,600 | |||||||
| Accounts payable | 551,756 | 506,592 | |||||||||
| Deferred revenue | 97,948 | 81,529 | |||||||||
| Accrued expenses and other current liabilities | 525,728 | 441,788 | |||||||||
| Current portion of closure, post-closure and remedial liabilities | 20,312 | 19,112 | |||||||||
| Current portion of operating lease liabilities | 81,345 | 75,226 | |||||||||
| Total current liabilities | 1,289,689 | 1,136,847 | |||||||||
| Other liabilities: | |||||||||||
Closure and post-closure liabilities, less current portion of $9,648 and $10,290, respectively | 131,194 | 125,038 | |||||||||
Remedial liabilities, less current portion of $10,664 and $8,822, respectively | 81,180 | 86,547 | |||||||||
| Long-term debt, less current portion | 2,877,298 | 2,763,563 | |||||||||
| Operating lease liabilities, less current portion | 178,294 | 184,308 | |||||||||
| Deferred tax liabilities | 400,248 | 384,207 | |||||||||
| Other long-term liabilities | 208,488 | 197,886 | |||||||||
| Total other liabilities | 3,876,702 | 3,741,549 | |||||||||
| Commitments and contingent liabilities (See Note 15) | |||||||||||
| Stockholders’ equity: | |||||||||||
Common stock, $0.01 par value: | |||||||||||
Authorized 80,000,000 shares; issued and outstanding 52,728,878 and 52,870,599 shares, respectively | 527 | 529 | |||||||||
| Additional paid-in capital | 143,038 | 193,896 | |||||||||
| Accumulated other comprehensive loss | (223,967) | (204,616) | |||||||||
| Retained earnings | 3,197,616 | 2,755,851 | |||||||||
| Total stockholders’ equity | 3,117,214 | 2,745,660 | |||||||||
| Total liabilities and stockholders’ equity | $ | 8,283,605 | $ | 7,624,056 | |||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||
| September 30, | September 30, | |||||||||||||||||||||||||
| 2026 | 2025 | 2026 | 2025 | |||||||||||||||||||||||
| Revenues: | ||||||||||||||||||||||||||
| Service revenues | $ | 1,529,035 | $ | 1,321,865 | $ | 4,209,324 | $ | 3,860,267 | ||||||||||||||||||
| Product revenues | 340,414 | 227,472 | 854,667 | 670,874 | ||||||||||||||||||||||
| Total revenues | 1,869,449 | 1,549,337 | 5,063,991 | 4,531,141 | ||||||||||||||||||||||
| Cost of revenues: (exclusive of items shown separately below) | ||||||||||||||||||||||||||
| Service revenues | 1,035,103 | 873,744 | 2,826,049 | 2,588,407 | ||||||||||||||||||||||
| Product revenues | 172,911 | 174,746 | 522,310 | 515,464 | ||||||||||||||||||||||
| Total cost of revenues | 1,208,014 | 1,048,490 | 3,348,359 | 3,103,871 | ||||||||||||||||||||||
| Selling, general and administrative expenses | 217,092 | 189,610 | 638,807 | 558,640 | ||||||||||||||||||||||
| Accretion of environmental liabilities | 3,531 | 3,499 | 10,575 | 10,710 | ||||||||||||||||||||||
| Depreciation and amortization | 122,703 | 114,729 | 360,309 | 342,994 | ||||||||||||||||||||||
| Income from operations | 318,109 | 193,009 | 705,941 | 514,926 | ||||||||||||||||||||||
| Other income, net | 1,524 | 3,517 | 1,223 | 1,982 | ||||||||||||||||||||||
Interest expense, net of interest income of $3,838, $6,497, $13,879, and $17,212, respectively | (37,438) | (35,700) | (108,500) | (108,883) | ||||||||||||||||||||||
| Income before provision for income taxes | 282,195 | 160,826 | 598,664 | 408,025 | ||||||||||||||||||||||
| Provision for income taxes | 74,095 | 42,027 | 156,899 | 103,641 | ||||||||||||||||||||||
| Net income | $ | 208,100 | $ | 118,799 | $ | 441,765 | $ | 304,384 | ||||||||||||||||||
| Earnings per share: | ||||||||||||||||||||||||||
| Basic | $ | 3.94 | $ | 2.22 | $ | 8.36 | $ | 5.67 | ||||||||||||||||||
| Diluted | $ | 3.93 | $ | 2.21 | $ | 8.34 | $ | 5.65 | ||||||||||||||||||
| Shares used to compute earnings per share - Basic | 52,752 | 53,518 | 52,812 | 53,659 | ||||||||||||||||||||||
| Shares used to compute earnings per share - Diluted | 52,897 | 53,713 | 52,969 | 53,871 | ||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||
| September 30, | September 30, | |||||||||||||||||||||||||
| 2026 | 2025 | 2026 | 2025 | |||||||||||||||||||||||
| Net income | $ | 208,100 | $ | 118,799 | $ | 441,765 | $ | 304,384 | ||||||||||||||||||
| Other comprehensive (loss) income, net of tax: | ||||||||||||||||||||||||||
Unrealized (loss) gain on available-for-sale securities | (202) | 69 | (534) | 164 | ||||||||||||||||||||||
| Unrealized (loss) gain on fair value of interest rate hedges | (1,825) | 524 | 6,517 | (3,953) | ||||||||||||||||||||||
| Reclassification adjustment for interest rate hedge amounts realized in net income | 1,814 | (2,630) | (5,643) | (7,823) | ||||||||||||||||||||||
| Pension adjustments | — | 13 | 7 | (20) | ||||||||||||||||||||||
| Foreign currency translation adjustments | (2,032) | (10,547) | (19,698) | 14,167 | ||||||||||||||||||||||
| Other comprehensive (loss) income, net of tax | (2,245) | (12,571) | (19,351) | 2,535 | ||||||||||||||||||||||
| Comprehensive income | $ | 205,855 | $ | 106,228 | $ | 422,414 | $ | 306,919 | ||||||||||||||||||
| Nine Months Ended | |||||||||||
| September 30, | |||||||||||
| 2026 | 2025 | ||||||||||
| Cash flows from operating activities: | |||||||||||
| Net income | $ | 441,765 | $ | 304,384 | |||||||
| Adjustments to reconcile net income to net cash from operating activities: | |||||||||||
| Depreciation and amortization | 360,309 | 342,994 | |||||||||
| Allowance for doubtful accounts | 9,571 | 6,520 | |||||||||
| Amortization of deferred financing costs and debt discount | 3,930 | 5,024 | |||||||||
| Accretion of environmental liabilities | 10,575 | 10,710 | |||||||||
| Changes in environmental liability estimates | (2,218) | (8,933) | |||||||||
| Other income, net | (1,223) | (1,982) | |||||||||
| Stock-based compensation | 36,141 | 22,620 | |||||||||
| Environmental expenditures | (9,756) | (10,960) | |||||||||
| Changes in assets and liabilities, net of acquisitions: | |||||||||||
| Accounts receivable and unbilled accounts receivable | (276,946) | (113,131) | |||||||||
| Inventories and supplies | (35,736) | 8,301 | |||||||||
Other current and non-current assets | 31,230 | (5,467) | |||||||||
| Accounts payable | 22,517 | (35,492) | |||||||||
| Other current and long-term liabilities | 74,514 | (12,956) | |||||||||
| Net cash from operating activities | 664,673 | 511,632 | |||||||||
| Cash flows used in investing activities: | |||||||||||
| Additions to property, plant and equipment | (397,480) | (303,169) | |||||||||
| Proceeds from sale and disposal of fixed assets | 8,483 | 15,250 | |||||||||
| Acquisitions, net of cash acquired | (689,044) | — | |||||||||
| Additions to intangible assets including costs to obtain or renew permits | (2,830) | (1,528) | |||||||||
| Purchases of available-for-sale securities | (37,665) | (62,108) | |||||||||
| Proceeds from sale of available-for-sale securities | 71,927 | 74,968 | |||||||||
| Net cash used in investing activities | (1,046,609) | (276,587) | |||||||||
Cash flows used in financing activities: | |||||||||||
| Change in uncashed checks | 1,716 | (2,639) | |||||||||
| Tax payments related to withholdings on vested restricted stock | (15,612) | (13,833) | |||||||||
| Repurchases of common stock | (77,133) | (117,001) | |||||||||
| Proceeds from employee stock purchase plan | 3,611 | 3,360 | |||||||||
| Deferred financing costs paid | (691) | — | |||||||||
| Payments on finance leases | (38,096) | (25,088) | |||||||||
| Principal payments on debt | (9,450) | (11,327) | |||||||||
| Borrowing from revolving credit facility | 120,000 | — | |||||||||
Net cash used in financing activities | (15,655) | (166,528) | |||||||||
| Effect of exchange rate change on cash | (5,180) | 3,488 | |||||||||
| (Decrease) increase in cash and cash equivalents | (402,771) | 72,005 | |||||||||
| Cash and cash equivalents, beginning of period | 826,315 | 687,192 | |||||||||
| Cash and cash equivalents, end of period | $ | 423,544 | $ | 759,197 | |||||||
| Supplemental information: | |||||||||||
| Cash payments for interest and income taxes: | |||||||||||
| Interest paid | $ | 114,037 | $ | 133,520 | |||||||
| Income taxes paid, net of refunds | 97,644 | 93,531 | |||||||||
| Non-cash investing activities: | |||||||||||
| Property, plant and equipment accrued | 45,391 | 36,604 | |||||||||
| ROU assets obtained in exchange for operating lease liabilities | 55,559 | 51,736 | |||||||||
| ROU assets obtained in exchange for finance lease liabilities | 60,586 | 59,937 | |||||||||
| Common Stock | Accumulated Other Comprehensive Loss | ||||||||||||||||||||||||||||||||||
| Number of Shares | $0.01 Par Value | Additional Paid-in Capital | Retained Earnings | Total Stockholders’ Equity | |||||||||||||||||||||||||||||||
| Balance at January 1, 2026 | 52,871 | $ | 529 | $ | 193,896 | $ | (204,616) | $ | 2,755,851 | $ | 2,745,660 | ||||||||||||||||||||||||
| Net income | — | — | — | — | 63,201 | 63,201 | |||||||||||||||||||||||||||||
| Other comprehensive loss | — | — | — | (8,633) | — | (8,633) | |||||||||||||||||||||||||||||
| Stock-based compensation | — | — | 9,578 | — | — | 9,578 | |||||||||||||||||||||||||||||
| Issuance of common stock for restricted share vesting, net of employee tax withholdings | 49 | — | (9,303) | — | — | (9,303) | |||||||||||||||||||||||||||||
| Repurchases of common stock | (87) | (1) | (24,999) | — | — | (25,000) | |||||||||||||||||||||||||||||
| Balance at March 31, 2026 | 52,833 | 528 | 169,172 | (213,249) | 2,819,052 | 2,775,503 | |||||||||||||||||||||||||||||
| Net income | — | — | — | — | 170,464 | 170,464 | |||||||||||||||||||||||||||||
| Other comprehensive loss | — | — | — | (8,473) | — | (8,473) | |||||||||||||||||||||||||||||
| Stock-based compensation | — | — | 14,818 | — | — | 14,818 | |||||||||||||||||||||||||||||
| Issuance of common stock for restricted share vesting, net of employee tax withholdings | 25 | 1 | (2,502) | — | — | (2,501) | |||||||||||||||||||||||||||||
| Repurchases of common stock | (84) | (1) | (24,999) | — | — | (25,000) | |||||||||||||||||||||||||||||
| Employee stock purchase plan | 17 | — | 3,611 | — | — | 3,611 | |||||||||||||||||||||||||||||
| Balance at June 30, 2026 | 52,791 | 528 | 160,100 | (221,722) | 2,989,516 | 2,928,422 | |||||||||||||||||||||||||||||
| Net income | — | — | — | — | 208,100 | 208,100 | |||||||||||||||||||||||||||||
| Other comprehensive loss | — | — | — | (2,245) | — | (2,245) | |||||||||||||||||||||||||||||
| Stock-based compensation | — | — | 11,745 | — | — | 11,745 | |||||||||||||||||||||||||||||
| Issuance of common stock for restricted share vesting, net of employee tax withholdings | 20 | — | (3,808) | — | — | (3,808) | |||||||||||||||||||||||||||||
| Repurchases of common stock | (82) | (1) | (24,999) | — | — | (25,000) | |||||||||||||||||||||||||||||
| Balance at September 30, 2026 | 52,729 | $ | 527 | $ | 143,038 | $ | (223,967) | $ | 3,197,616 | $ | 3,117,214 | ||||||||||||||||||||||||
| Common Stock | Accumulated Other Comprehensive Loss | ||||||||||||||||||||||||||||||||||
| Number of Shares | $0.01 Par Value | Additional Paid-in Capital | Retained Earnings | Total Stockholders’ Equity | |||||||||||||||||||||||||||||||
| Balance at January 1, 2025 | 53,833 | $ | 538 | $ | 421,749 | $ | (213,635) | $ | 2,364,877 | $ | 2,573,529 | ||||||||||||||||||||||||
| Net income | — | — | — | — | 58,680 | 58,680 | |||||||||||||||||||||||||||||
| Other comprehensive loss | — | — | — | (4,932) | — | (4,932) | |||||||||||||||||||||||||||||
| Stock-based compensation | — | — | 7,635 | — | — | 7,635 | |||||||||||||||||||||||||||||
| Issuance of common stock for restricted share vesting, net of employee tax withholdings | 59 | 1 | (8,689) | — | — | (8,688) | |||||||||||||||||||||||||||||
| Repurchases of common stock | (256) | (3) | (54,997) | — | — | (55,000) | |||||||||||||||||||||||||||||
| Balance at March 31, 2025 | 53,636 | 536 | 365,698 | (218,567) | 2,423,557 | 2,571,224 | |||||||||||||||||||||||||||||
| Net income | — | — | — | — | 126,905 | 126,905 | |||||||||||||||||||||||||||||
| Other comprehensive income | — | — | — | 20,038 | — | 20,038 | |||||||||||||||||||||||||||||
| Stock-based compensation | — | — | 6,063 | — | — | 6,063 | |||||||||||||||||||||||||||||
| Issuance of common stock for restricted share vesting, net of employee tax withholdings | 24 | — | (1,768) | — | — | (1,768) | |||||||||||||||||||||||||||||
| Repurchases of common stock | (62) | — | (11,755) | — | — | (11,755) | |||||||||||||||||||||||||||||
| Employee stock purchase plan | 16 | — | 3,360 | — | — | 3,360 | |||||||||||||||||||||||||||||
| Balance at June 30, 2025 | 53,614 | 536 | 361,598 | (198,529) | 2,550,462 | 2,714,067 | |||||||||||||||||||||||||||||
| Net income | — | — | — | — | 118,799 | 118,799 | |||||||||||||||||||||||||||||
| Other comprehensive loss | — | — | — | (12,571) | — | (12,571) | |||||||||||||||||||||||||||||
| Stock-based compensation | — | — | 8,922 | — | — | 8,922 | |||||||||||||||||||||||||||||
| Issuance of common stock for restricted share vesting, net of employee tax withholdings | 25 | — | (3,377) | — | — | (3,377) | |||||||||||||||||||||||||||||
| Repurchases of common stock | (208) | (2) | (49,998) | — | — | (50,000) | |||||||||||||||||||||||||||||
| Balance at September 30, 2025 | 53,431 | $ | 534 | $ | 317,145 | $ | (211,100) | $ | 2,669,261 | $ | 2,775,840 | ||||||||||||||||||||||||
| Three Months Ended September 30, 2026 | ||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Corporate | Total | |||||||||||||||||||||||
| Primary Geographical Markets | ||||||||||||||||||||||||||
| United States | $ | 1,410,767 | $ | 297,503 | $ | — | $ | 1,708,270 | ||||||||||||||||||
| Canada | 127,671 | 33,508 | — | 161,179 | ||||||||||||||||||||||
| Total third-party revenues | $ | 1,538,438 | $ | 331,011 | $ | — | $ | 1,869,449 | ||||||||||||||||||
| Sources of Revenue | ||||||||||||||||||||||||||
| Technical Services | $ | 507,222 | $ | — | $ | — | $ | 507,222 | ||||||||||||||||||
Industrial Services | 336,681 | — | — | 336,681 | ||||||||||||||||||||||
| Field and Emergency Response Services | 401,189 | — | — | 401,189 | ||||||||||||||||||||||
| Safety-Kleen Environmental Services | 293,346 | 88,614 | — | 381,960 | ||||||||||||||||||||||
| Safety-Kleen Oil | — | 242,397 | — | 242,397 | ||||||||||||||||||||||
| Total third-party revenues | $ | 1,538,438 | $ | 331,011 | $ | — | $ | 1,869,449 | ||||||||||||||||||
| Three Months Ended September 30, 2025 | ||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Corporate | Total | |||||||||||||||||||||||
| Primary Geographical Markets | ||||||||||||||||||||||||||
| United States | $ | 1,194,300 | $ | 202,483 | $ | — | $ | 1,396,783 | ||||||||||||||||||
| Canada | 124,280 | 28,274 | — | 152,554 | ||||||||||||||||||||||
| Total third-party revenues | $ | 1,318,580 | $ | 230,757 | $ | — | $ | 1,549,337 | ||||||||||||||||||
| Sources of Revenue | ||||||||||||||||||||||||||
| Technical Services | $ | 490,768 | $ | — | $ | — | $ | 490,768 | ||||||||||||||||||
Industrial Services | 332,102 | — | — | 332,102 | ||||||||||||||||||||||
| Field and Emergency Response Services | 232,262 | — | — | 232,262 | ||||||||||||||||||||||
| Safety-Kleen Environmental Services | 263,448 | 76,601 | — | 340,049 | ||||||||||||||||||||||
| Safety-Kleen Oil | — | 154,156 | — | 154,156 | ||||||||||||||||||||||
| Total third-party revenues | $ | 1,318,580 | $ | 230,757 | $ | — | $ | 1,549,337 | ||||||||||||||||||
| Nine Months Ended September 30, 2026 | ||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Corporate | Total | |||||||||||||||||||||||
| Primary Geographical Markets | ||||||||||||||||||||||||||
| United States | $ | 3,873,397 | $ | 757,091 | $ | — | $ | 4,630,488 | ||||||||||||||||||
| Canada | 352,021 | 81,482 | — | 433,503 | ||||||||||||||||||||||
| Total third-party revenues | $ | 4,225,418 | $ | 838,573 | $ | — | $ | 5,063,991 | ||||||||||||||||||
| Sources of Revenue | ||||||||||||||||||||||||||
| Technical Services | $ | 1,501,164 | $ | — | $ | — | $ | 1,501,164 | ||||||||||||||||||
Industrial Services | 998,350 | — | — | 998,350 | ||||||||||||||||||||||
| Field and Emergency Response Services | 880,459 | — | — | 880,459 | ||||||||||||||||||||||
| Safety-Kleen Environmental Services | 845,445 | 254,082 | — | 1,099,527 | ||||||||||||||||||||||
| Safety-Kleen Oil | — | 584,491 | — | 584,491 | ||||||||||||||||||||||
| Total third-party revenues | $ | 4,225,418 | $ | 838,573 | $ | — | $ | 5,063,991 | ||||||||||||||||||
| Nine Months Ended September 30, 2025 | ||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Corporate | Total | |||||||||||||||||||||||
| Primary Geographical Markets | ||||||||||||||||||||||||||
| United States | $ | 3,519,337 | $ | 596,612 | $ | 186 | $ | 4,116,135 | ||||||||||||||||||
| Canada | 336,340 | 78,666 | — | 415,006 | ||||||||||||||||||||||
| Total third-party revenues | $ | 3,855,677 | $ | 675,278 | $ | 186 | $ | 4,531,141 | ||||||||||||||||||
| Sources of Revenue | ||||||||||||||||||||||||||
| Technical Services | $ | 1,380,394 | $ | — | $ | — | $ | 1,380,394 | ||||||||||||||||||
Industrial Services and Other | 1,016,040 | — | 186 | 1,016,226 | ||||||||||||||||||||||
| Field and Emergency Response Services | 690,755 | — | — | 690,755 | ||||||||||||||||||||||
| Safety-Kleen Environmental Services | 768,488 | 213,965 | — | 982,453 | ||||||||||||||||||||||
| Safety-Kleen Oil | — | 461,313 | — | 461,313 | ||||||||||||||||||||||
| Total third-party revenues | $ | 3,855,677 | $ | 675,278 | $ | 186 | $ | 4,531,141 | ||||||||||||||||||
| (in thousands) | September 30, 2026 | December 31, 2025 | ||||||||||||
| Receivables | $ | 1,273,770 | $ | 1,044,137 | ||||||||||
| Contract assets (unbilled receivables) | 218,442 | 160,888 | ||||||||||||
| Contract liabilities (deferred revenue) | 97,948 | 81,529 | ||||||||||||
At September 18, 2026 | |||||
| Accounts receivable, including unbilled receivables | $ | 16,503 | |||
| Inventories and supplies | 300 | ||||
| Prepaid expenses and other current assets | 449 | ||||
| Property, plant and equipment | 23,230 | ||||
| Permits and other intangible assets | 126,500 | ||||
| Operating lease right-of-use assets | 4,192 | ||||
| Accounts payable | (4,694) | ||||
| Accrued expenses and other current liabilities | (3,243) | ||||
| Current portion of operating lease liabilities | (865) | ||||
| Operating lease liabilities, less current portion | (3,327) | ||||
| Total identifiable net assets | 159,045 | ||||
| Goodwill | 141,704 | ||||
| Total purchase price | $ | 300,749 | |||
| At Acquisition Date As Reported June 30, 2026 | Measurement Period Adjustments | At Acquisition Date As Reported September 30, 2026 | |||||||||||||||
| Accounts receivable, including unbilled receivables | $ | 6,855 | $ | 72 | $ | 6,927 | |||||||||||
| Inventories and supplies | 148 | — | 148 | ||||||||||||||
| Prepaid expenses and other current assets | 1,844 | 212 | 2,056 | ||||||||||||||
| Property, plant and equipment | 18,781 | 8,497 | 27,278 | ||||||||||||||
| Permits and other intangible assets | 91,400 | (5,000) | 86,400 | ||||||||||||||
| Operating lease right-of-use assets | 160 | — | 160 | ||||||||||||||
| Other long-term assets | 10 | — | 10 | ||||||||||||||
| Accounts payable | (3,225) | 4 | (3,221) | ||||||||||||||
| Accrued expenses and other current liabilities | (796) | (90) | (886) | ||||||||||||||
| Current portion of operating lease liabilities | (118) | — | (118) | ||||||||||||||
| Operating lease liabilities, less current portion | (42) | — | (42) | ||||||||||||||
| Deferred tax liabilities | — | (16,227) | (16,227) | ||||||||||||||
| Closure and post-closure liabilities | — | (14) | (14) | ||||||||||||||
| Total identifiable net assets | 115,017 | (12,546) | 102,471 | ||||||||||||||
| Goodwill | 110,756 | 12,153 | 122,909 | ||||||||||||||
| Total purchase price | $ | 225,773 | $ | (393) | $ | 225,380 | |||||||||||
| At Acquisition Date As Reported June 30, 2026 | Measurement Period Adjustments | At Acquisition Date As Reported September 30, 2026 | |||||||||||||||
| Inventories and supplies | $ | 177 | $ | — | $ | 177 | |||||||||||
| Property, plant and equipment | 13,386 | 1,723 | 15,109 | ||||||||||||||
| Permits and other intangible assets | 33,800 | — | 33,800 | ||||||||||||||
| Operating lease right-of-use assets | 5,634 | — | 5,634 | ||||||||||||||
| Accrued expenses and other current liabilities | (180) | (1,735) | (1,915) | ||||||||||||||
| Current portion of operating lease liabilities | (1,128) | — | (1,128) | ||||||||||||||
| Operating lease liabilities, less current portion | (4,506) | — | (4,506) | ||||||||||||||
| Closure and post-closure liabilities | — | (1,723) | (1,723) | ||||||||||||||
| Total identifiable net assets | 47,183 | (1,735) | 45,448 | ||||||||||||||
| Goodwill | 84,637 | 2,420 | 87,057 | ||||||||||||||
| Total purchase price | $ | 131,820 | $ | 685 | $ | 132,505 | |||||||||||
| September 30, 2026 | December 31, 2025 | ||||||||||
| Supplies | $ | 223,624 | $ | 217,028 | |||||||
| Oil and oil related products | 149,312 | 123,883 | |||||||||
| Solvent and solutions | 12,840 | 11,589 | |||||||||
| Other | 22,146 | 19,588 | |||||||||
| Total inventories and supplies | $ | 407,922 | $ | 372,088 | |||||||
| September 30, 2026 | December 31, 2025 | ||||||||||
| Land | $ | 233,061 | $ | 193,438 | |||||||
| Asset retirement costs (non-landfill) | 41,807 | 40,232 | |||||||||
| Landfill assets | 285,720 | 278,700 | |||||||||
Buildings and improvements (1) | 799,711 | 753,404 | |||||||||
Vehicles (2) | 1,718,391 | 1,583,387 | |||||||||
Equipment (3) | 2,755,823 | 2,652,027 | |||||||||
| Construction in progress | 159,004 | 90,182 | |||||||||
| 5,993,517 | 5,591,370 | ||||||||||
| Less - accumulated depreciation and amortization | 3,236,234 | 3,050,303 | |||||||||
| Total property, plant and equipment, net | $ | 2,757,283 | $ | 2,541,067 | |||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Totals | |||||||||||||||
| Balance at January 1, 2026 | $ | 1,297,478 | $ | 181,572 | $ | 1,479,050 | |||||||||||
| Increase from current period acquisitions | 351,670 | 14,306 | 365,976 | ||||||||||||||
| Foreign currency translation | (1,244) | (509) | (1,753) | ||||||||||||||
| Balance at September 30, 2026 | $ | 1,647,904 | $ | 195,369 | $ | 1,843,273 | |||||||||||
| September 30, 2026 | December 31, 2025 | ||||||||||||||||||||||||||||||||||
| Cost | Accumulated Amortization | Net | Cost | Accumulated Amortization | Net | ||||||||||||||||||||||||||||||
| Permits | $ | 197,686 | $ | 137,239 | $ | 60,447 | $ | 196,224 | $ | 132,308 | $ | 63,916 | |||||||||||||||||||||||
Customer and supplier relationships | 933,316 | 305,131 | 628,185 | 698,381 | 292,813 | 405,568 | |||||||||||||||||||||||||||||
Other intangible assets | 124,945 | 66,441 | 58,504 | 121,030 | 57,438 | 63,592 | |||||||||||||||||||||||||||||
Total amortizable permits and other intangible assets | 1,255,947 | 508,811 | 747,136 | 1,015,635 | 482,559 | 533,076 | |||||||||||||||||||||||||||||
Trademarks and trade names | 119,619 | — | 119,619 | 119,951 | — | 119,951 | |||||||||||||||||||||||||||||
Total permits and other intangible assets | $ | 1,375,566 | $ | 508,811 | $ | 866,755 | $ | 1,135,586 | $ | 482,559 | $ | 653,027 | |||||||||||||||||||||||
| Years Ending December 31, | Expected Amortization | ||||
| 2026 (three months) | $ | 19,888 | |||
| 2027 | 75,533 | ||||
| 2028 | 65,863 | ||||
| 2029 | 60,257 | ||||
| 2030 | 54,565 | ||||
| Thereafter | 471,030 | ||||
| $ | 747,136 | ||||
| September 30, 2026 | December 31, 2025 | ||||||||||
| Accrued compensation and benefits | $ | 148,816 | $ | 144,689 | |||||||
| Accrued insurance | 126,077 | 116,675 | |||||||||
| Accrued income, real estate, sales and other taxes | 93,416 | 42,082 | |||||||||
| Accrued interest | 29,561 | 30,893 | |||||||||
| Accrued other | 127,858 | 107,449 | |||||||||
| $ | 525,728 | $ | 441,788 | ||||||||
| Landfill Retirement Liability | Non-Landfill Retirement Liability | Total | |||||||||||||||
| Balance at January 1, 2026 | $ | 59,763 | $ | 75,565 | $ | 135,328 | |||||||||||
| Liabilities assumed in acquisitions | — | 1,737 | 1,737 | ||||||||||||||
| New asset retirement obligations | 3,014 | — | 3,014 | ||||||||||||||
| Accretion | 3,643 | 4,312 | 7,955 | ||||||||||||||
| Changes in estimates recorded to consolidated statement of operations | (1,895) | (1,007) | (2,902) | ||||||||||||||
| Changes in estimates recorded to consolidated balance sheet | (1,515) | 367 | (1,148) | ||||||||||||||
| Expenditures | (1,983) | (357) | (2,340) | ||||||||||||||
| Currency translation and other | (103) | (699) | (802) | ||||||||||||||
| Balance at September 30, 2026 | $ | 60,924 | $ | 79,918 | $ | 140,842 | |||||||||||
| Remedial Liabilities for Landfill Sites | Remedial Liabilities for Inactive Sites | Remedial Liabilities (Including Superfund) for Non-Landfill Operations | Total | ||||||||||||||||||||
| Balance at January 1, 2026 | $ | 1,928 | $ | 54,523 | $ | 38,918 | $ | 95,369 | |||||||||||||||
| Accretion | 70 | 1,690 | 860 | 2,620 | |||||||||||||||||||
| Changes in estimates recorded to consolidated statement of operations | 18 | 523 | 143 | 684 | |||||||||||||||||||
| Expenditures | (35) | (3,683) | (3,698) | (7,416) | |||||||||||||||||||
| Currency translation and other | — | 5 | 582 | 587 | |||||||||||||||||||
| Balance at September 30, 2026 | $ | 1,981 | $ | 53,058 | $ | 36,805 | $ | 91,844 | |||||||||||||||
| September 30, 2026 | December 31, 2025 | ||||||||||
| Current Portion of Long-Term Debt: | |||||||||||
| Secured senior term loans | $ | 12,600 | $ | 12,600 | |||||||
| Long-Term Debt: | |||||||||||
Secured senior term loans due October 9, 2032 (“2032 Term Loans”) | $ | 1,237,950 | $ | 1,247,400 | |||||||
Unsecured senior notes, at 5.125%, due July 15, 2029 (“2029 Notes”) | 300,000 | 300,000 | |||||||||
Unsecured senior notes, at 6.375%, due February 1, 2031 (“2031 Notes”) | 500,000 | 500,000 | |||||||||
Unsecured senior notes, at 5.750%, due October 15, 2033 (“2033 Notes”) | 745,000 | 745,000 | |||||||||
| Revolving credit facility | 120,000 | — | |||||||||
| Long-term debt, at par | $ | 2,902,950 | $ | 2,792,400 | |||||||
| Unamortized debt issuance costs and discount, net | (25,652) | (28,837) | |||||||||
| Long-term debt, at carrying value | $ | 2,877,298 | $ | 2,763,563 | |||||||
| Three Months Ended September 30, | Nine Months Ended September 30, | ||||||||||||||||||||||
| 2026 | 2025 | 2026 | 2025 | ||||||||||||||||||||
| Numerator for basic and diluted earnings per share: | |||||||||||||||||||||||
| Net income | $ | 208,100 | $ | 118,799 | $ | 441,765 | $ | 304,384 | |||||||||||||||
| Denominator: | |||||||||||||||||||||||
| Weighted-average shares outstanding, basic | 52,752 | 53,518 | 52,812 | 53,659 | |||||||||||||||||||
| Dilutive impact of equity awards | 145 | 195 | 157 | 212 | |||||||||||||||||||
Weighted-average shares outstanding, diluted | 52,897 | 53,713 | 52,969 | 53,871 | |||||||||||||||||||
| Basic earnings per share: | $ | 3.94 | $ | 2.22 | $ | 8.36 | $ | 5.67 | |||||||||||||||
| Diluted earnings per share: | $ | 3.93 | $ | 2.21 | $ | 8.34 | $ | 5.65 | |||||||||||||||
| Foreign Currency Translation Adjustments | Unrealized Gain (Loss) on Available-For-Sale Securities | Unrealized Gain on Fair Value of Interest Rate Hedges | Unrealized Loss on Pension | Total | |||||||||||||||||||||||||
| Balance at January 1, 2026 | $ | (214,514) | $ | 157 | $ | 9,933 | $ | (192) | $ | (204,616) | |||||||||||||||||||
| Other comprehensive (loss) income before reclassifications | (19,698) | (676) | 8,927 | 7 | (11,440) | ||||||||||||||||||||||||
| Amounts reclassified out of accumulated other comprehensive loss | — | — | (7,730) | — | (7,730) | ||||||||||||||||||||||||
| Tax benefit (provision) | — | 142 | (323) | — | (181) | ||||||||||||||||||||||||
| Other comprehensive (loss) income | (19,698) | (534) | 874 | 7 | (19,351) | ||||||||||||||||||||||||
| Balance at September 30, 2026 | $ | (234,212) | $ | (377) | $ | 10,807 | $ | (185) | $ | (223,967) | |||||||||||||||||||
| Component of Accumulated Other Comprehensive Loss | Three Months Ended September 30, 2026 | Nine Months Ended September 30, 2026 | Location | |||||||||||||||||
| Unrealized Gain on Fair Value of Interest Rate Hedges | $ | 2,617 | $ | 7,730 | Interest expense, net of interest income | |||||||||||||||
| Restricted Stock | Number of Shares | Weighted Average Grant-Date Fair Value | |||||||||
| Balance at January 1, 2026 | 313,820 | $ | 176.06 | ||||||||
| Granted | 86,604 | 273.83 | |||||||||
| Vested | (123,840) | 166.41 | |||||||||
| Forfeited | (13,932) | 189.14 | |||||||||
| Balance at September 30, 2026 | 262,652 | $ | 212.15 | ||||||||
| Performance Stock | Number of Shares | Weighted Average Grant-Date Fair Value | |||||||||
| Balance at January 1, 2026 | 147,404 | $ | 182.63 | ||||||||
| Granted | 83,920 | 260.39 | |||||||||
| Vested | (27,275) | 106.60 | |||||||||
Forfeited (1) | (45,079) | 189.70 | |||||||||
| Balance at September 30, 2026 | 158,970 | $ | 234.72 | ||||||||
| For the Three Months Ended September 30, 2026 | |||||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Segment Revenues | Corporate | Total Consolidated Revenues | |||||||||||||||||||||||||
| Third-party revenues | $ | 1,538,438 | $ | 331,011 | $ | 1,869,449 | $ | — | $ | 1,869,449 | |||||||||||||||||||
| Intersegment revenues (expense), net | 12,683 | (12,683) | — | — | — | ||||||||||||||||||||||||
| Direct revenues | $ | 1,551,121 | $ | 318,328 | $ | 1,869,449 | $ | — | $ | 1,869,449 | |||||||||||||||||||
| For the Three Months Ended September 30, 2025 | |||||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Segment Revenues | Corporate | Total Consolidated Revenues | |||||||||||||||||||||||||
| Third-party revenues | $ | 1,318,580 | $ | 230,757 | $ | 1,549,337 | $ | — | $ | 1,549,337 | |||||||||||||||||||
| Intersegment revenues (expense), net | 12,720 | (12,720) | — | — | — | ||||||||||||||||||||||||
| Direct revenues | $ | 1,331,300 | $ | 218,037 | $ | 1,549,337 | $ | — | $ | 1,549,337 | |||||||||||||||||||
| For the Nine Months Ended September 30, 2026 | |||||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Segment Revenues | Corporate | Total Consolidated Revenues | |||||||||||||||||||||||||
| Third-party revenues | $ | 4,225,418 | $ | 838,573 | $ | 5,063,991 | $ | — | $ | 5,063,991 | |||||||||||||||||||
| Intersegment revenues (expense), net | 34,792 | (34,792) | — | — | — | ||||||||||||||||||||||||
| Direct revenues | $ | 4,260,210 | $ | 803,781 | $ | 5,063,991 | $ | — | $ | 5,063,991 | |||||||||||||||||||
| For the Nine Months Ended September 30, 2025 | |||||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Segment Revenues | Corporate | Total Consolidated Revenues | |||||||||||||||||||||||||
| Third-party revenues | $ | 3,855,677 | $ | 675,278 | $ | 4,530,955 | $ | 186 | $ | 4,531,141 | |||||||||||||||||||
| Intersegment revenues (expense), net | 36,771 | (36,771) | — | — | — | ||||||||||||||||||||||||
| Direct revenues | $ | 3,892,448 | $ | 638,507 | $ | 4,530,955 | $ | 186 | $ | 4,531,141 | |||||||||||||||||||
| For the Three Months Ended September 30, 2026 | |||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Reportable Segments | |||||||||||||||
| Direct Revenues | $ | 1,551,121 | $ | 318,328 | $ | 1,869,449 | |||||||||||
| Cost of Revenues | 1,014,061 | 173,343 | 1,187,404 | ||||||||||||||
| Selling, General and Administrative Expenses | 111,668 | 18,503 | 130,171 | ||||||||||||||
| Total Reportable Segment Adjusted EBITDA | $ | 425,392 | $ | 126,482 | $ | 551,874 | |||||||||||
| For the Three Months Ended September 30, 2025 | |||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Reportable Segments | |||||||||||||||
| Direct Revenues | $ | 1,331,300 | $ | 218,037 | $ | 1,549,337 | |||||||||||
| Cost of Revenues | 871,487 | 158,545 | 1,030,032 | ||||||||||||||
| Selling, General and Administrative Expenses | 102,584 | 18,555 | 121,139 | ||||||||||||||
| Total Reportable Segment Adjusted EBITDA | $ | 357,229 | $ | 40,937 | $ | 398,166 | |||||||||||
| For the Nine Months Ended September 30, 2026 | |||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Reportable Segments | |||||||||||||||
| Direct Revenues | $ | 4,260,210 | $ | 803,781 | $ | 5,063,991 | |||||||||||
| Cost of Revenues | 2,810,171 | 490,618 | 3,300,789 | ||||||||||||||
| Selling, General and Administrative Expenses | 328,142 | 60,707 | 388,849 | ||||||||||||||
| Total Reportable Segment Adjusted EBITDA | $ | 1,121,897 | $ | 252,456 | $ | 1,374,353 | |||||||||||
| For the Nine Months Ended September 30, 2025 | |||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Reportable Segments | |||||||||||||||
| Direct Revenues | $ | 3,892,448 | $ | 638,507 | $ | 4,530,955 | |||||||||||
| Cost of Revenues | 2,592,300 | 476,550 | 3,068,850 | ||||||||||||||
| Selling, General and Administrative Expenses | 292,134 | 54,455 | 346,589 | ||||||||||||||
| Total Reportable Segment Adjusted EBITDA | $ | 1,008,014 | $ | 107,502 | $ | 1,115,516 | |||||||||||
| Three Months Ended | Nine Months Ended | ||||||||||||||||||||||
| September 30, | September 30, | ||||||||||||||||||||||
| 2026 | 2025 | 2026 | 2025 | ||||||||||||||||||||
| Adjusted EBITDA: | |||||||||||||||||||||||
| Environmental Services | $ | 425,392 | $ | 357,229 | $ | 1,121,897 | $ | 1,008,014 | |||||||||||||||
| Safety-Kleen Sustainability Solutions | 126,482 | 40,937 | 252,456 | 107,502 | |||||||||||||||||||
| Total Reportable Segment Adjusted EBITDA | 551,874 | 398,166 | 1,374,353 | 1,115,516 | |||||||||||||||||||
| Reconciliation to Consolidated Statements of Operations: | |||||||||||||||||||||||
Corporate Costs(1) | 95,786 | 78,007 | 261,387 | 224,266 | |||||||||||||||||||
| Accretion of environmental liabilities | 3,531 | 3,499 | 10,575 | 10,710 | |||||||||||||||||||
| Stock-based compensation | 11,745 | 8,922 | 36,141 | 22,620 | |||||||||||||||||||
| Depreciation and amortization | 122,703 | 114,729 | 360,309 | 342,994 | |||||||||||||||||||
| Income from operations | 318,109 | 193,009 | 705,941 | 514,926 | |||||||||||||||||||
| Other income, net | (1,524) | (3,517) | (1,223) | (1,982) | |||||||||||||||||||
| Interest expense, net of interest income | 37,438 | 35,700 | 108,500 | 108,883 | |||||||||||||||||||
| Income from operations before provision for income taxes | $ | 282,195 | $ | 160,826 | $ | 598,664 | $ | 408,025 | |||||||||||||||
| Summary of Operations | |||||||||||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | September 30, | ||||||||||||||||||||||||||||||||||||||||||||||
| 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||
Direct Revenues (1): | |||||||||||||||||||||||||||||||||||||||||||||||
| Environmental Services | $ | 1,551,121 | $ | 1,331,300 | $ | 219,821 | 16.5% | $ | 4,260,210 | $ | 3,892,448 | $ | 367,762 | 9.4% | |||||||||||||||||||||||||||||||||
| Safety-Kleen Sustainability Solutions | 318,328 | 218,037 | 100,291 | 46.0 | 803,781 | 638,507 | 165,274 | 25.9 | |||||||||||||||||||||||||||||||||||||||
Corporate | — | — | — | N/M | — | 186 | (186) | N/M | |||||||||||||||||||||||||||||||||||||||
| Total | 1,869,449 | 1,549,337 | 320,112 | 20.7 | 5,063,991 | 4,531,141 | 532,850 | 11.8 | |||||||||||||||||||||||||||||||||||||||
Cost of Revenues (2): | |||||||||||||||||||||||||||||||||||||||||||||||
| Environmental Services | 1,014,061 | 871,487 | 142,574 | 16.4 | 2,810,171 | 2,592,300 | 217,871 | 8.4 | |||||||||||||||||||||||||||||||||||||||
| Safety-Kleen Sustainability Solutions | 173,343 | 158,545 | 14,798 | 9.3 | 490,618 | 476,550 | 14,068 | 3.0 | |||||||||||||||||||||||||||||||||||||||
Corporate | 20,610 | 18,458 | 2,152 | N/M | 47,570 | 35,021 | 12,549 | N/M | |||||||||||||||||||||||||||||||||||||||
| Total | 1,208,014 | 1,048,490 | 159,524 | 15.2 | 3,348,359 | 3,103,871 | 244,488 | 7.9 | |||||||||||||||||||||||||||||||||||||||
Selling, General & Administrative Expenses (3): | |||||||||||||||||||||||||||||||||||||||||||||||
| Environmental Services | 111,668 | 102,584 | 9,084 | 8.9 | 328,142 | 292,134 | 36,008 | 12.3 | |||||||||||||||||||||||||||||||||||||||
| Safety-Kleen Sustainability Solutions | 18,503 | 18,555 | (52) | (0.3) | 60,707 | 54,455 | 6,252 | 11.5 | |||||||||||||||||||||||||||||||||||||||
Corporate | 75,176 | 59,549 | 15,627 | 26.2 | 213,817 | 189,431 | 24,386 | 12.9 | |||||||||||||||||||||||||||||||||||||||
| Total | 205,347 | 180,688 | 24,659 | 13.6 | 602,666 | 536,020 | 66,646 | 12.4 | |||||||||||||||||||||||||||||||||||||||
| Adjusted EBITDA: | |||||||||||||||||||||||||||||||||||||||||||||||
| Environmental Services | 425,392 | 357,229 | 68,163 | 19.1 | 1,121,897 | 1,008,014 | 113,883 | 11.3 | |||||||||||||||||||||||||||||||||||||||
| Safety-Kleen Sustainability Solutions | 126,482 | 40,937 | 85,545 | 209.0 | 252,456 | 107,502 | 144,954 | 134.8 | |||||||||||||||||||||||||||||||||||||||
Corporate | (95,786) | (78,007) | (17,779) | (22.8) | (261,387) | (224,266) | (37,121) | (16.6) | |||||||||||||||||||||||||||||||||||||||
| Total | $ | 456,088 | $ | 320,159 | $ | 135,929 | 42.5% | $ | 1,112,966 | $ | 891,250 | $ | 221,716 | 24.9% | |||||||||||||||||||||||||||||||||
| Adjusted EBITDA as a % of Direct Revenues: | |||||||||||||||||||||||||||||||||||||||||||||||
Environmental Services (4) | 27.4 | % | 26.8 | % | 0.6 | % | 26.3 | % | 25.9 | % | 0.4 | % | |||||||||||||||||||||||||||||||||||
Safety-Kleen Sustainability Solutions (4) | 39.7 | % | 18.8 | % | 20.9 | % | 31.4 | % | 16.8 | % | 14.6 | % | |||||||||||||||||||||||||||||||||||
Corporate (5) | (5.1) | % | (5.0) | % | (0.1) | % | (5.2) | % | (4.9) | % | (0.3) | % | |||||||||||||||||||||||||||||||||||
| Total | 24.4 | % | 20.7 | % | 3.7 | % | 22.0 | % | 19.7 | % | 2.3 | % | |||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | 2026 over 2025 | September 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Direct revenues | $ | 1,551,121 | $ | 1,331,300 | $ | 219,821 | 16.5 | % | $ | 4,260,210 | $ | 3,892,448 | $ | 367,762 | 9.4 | % | ||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | 2026 over 2025 | September 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Direct revenues | $ | 318,328 | $ | 218,037 | $ | 100,291 | 46.0 | % | $ | 803,781 | $ | 638,507 | $ | 165,274 | 25.9 | % | ||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | 2026 over 2025 | September 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Cost of revenues | $ | 1,014,061 | $ | 871,487 | $ | 142,574 | 16.4 | % | $ | 2,810,171 | $ | 2,592,300 | $ | 217,871 | 8.4 | % | ||||||||||||||||||||||||||||||||||
| As a % of Direct revenues | 65.4 | % | 65.5 | % | (0.1) | % | 66.0 | % | 66.6 | % | (0.6) | % | ||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | 2026 over 2025 | September 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Cost of revenues | $ | 173,343 | $ | 158,545 | $ | 14,798 | 9.3 | % | $ | 490,618 | $ | 476,550 | $ | 14,068 | 3.0 | % | ||||||||||||||||||||||||||||||||||
| As a % of Direct revenues | 54.5 | % | 72.7 | % | (18.2) | % | 61.0 | % | 74.6 | % | (13.6) | % | ||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | 2026 over 2025 | September 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| SG&A expenses | $ | 111,668 | $ | 102,584 | $ | 9,084 | 8.9 | % | $ | 328,142 | $ | 292,134 | $ | 36,008 | 12.3 | % | ||||||||||||||||||||||||||||||||||
| As a % of Direct revenues | 7.2 | % | 7.7 | % | (0.5) | % | 7.7 | % | 7.5 | % | 0.2 | % | ||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | 2026 over 2025 | September 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| SG&A expenses | $ | 18,503 | $ | 18,555 | $ | (52) | (0.3) | % | $ | 60,707 | $ | 54,455 | $ | 6,252 | 11.5 | % | ||||||||||||||||||||||||||||||||||
| As a % of Direct revenues | 5.8 | % | 8.5 | % | (2.7) | % | 7.6 | % | 8.5 | % | (0.9) | % | ||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | 2026 over 2025 | September 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| SG&A expenses | $ | 75,176 | $ | 59,549 | $ | 15,627 | 26.2 | % | $ | 213,817 | $ | 189,431 | $ | 24,386 | 12.9 | % | ||||||||||||||||||||||||||||||||||
| As a % of Total Company Direct revenues | 4.0 | % | 3.8 | % | 0.2 | % | 4.2 | % | 4.2 | % | — | % | ||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||
| September 30, | September 30, | |||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | 2026 | 2025 | ||||||||||||||||||||||
| Net income | $ | 208,100 | $ | 118,799 | $ | 441,765 | $ | 304,384 | ||||||||||||||||||
| Accretion of environmental liabilities | 3,531 | 3,499 | 10,575 | 10,710 | ||||||||||||||||||||||
| Stock-based compensation | 11,745 | 8,922 | 36,141 | 22,620 | ||||||||||||||||||||||
| Depreciation and amortization | 122,703 | 114,729 | 360,309 | 342,994 | ||||||||||||||||||||||
| Other income, net | (1,524) | (3,517) | (1,223) | (1,982) | ||||||||||||||||||||||
| Interest expense, net of interest income | 37,438 | 35,700 | 108,500 | 108,883 | ||||||||||||||||||||||
| Provision for income taxes | 74,095 | 42,027 | 156,899 | 103,641 | ||||||||||||||||||||||
| Adjusted EBITDA | $ | 456,088 | $ | 320,159 | $ | 1,112,966 | $ | 891,250 | ||||||||||||||||||
| As a % of direct revenues | 24.4 | % | 20.7 | % | 22.0 | % | 19.7 | % | ||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | 2026 over 2025 | September 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Depreciation of fixed assets and amortization of landfills and finance leases | $ | 106,039 | $ | 101,292 | $ | 4,747 | 4.7 | % | $ | 314,488 | $ | 302,532 | $ | 11,956 | 4.0 | % | ||||||||||||||||||||||||||||||||||
| Permits and other intangibles amortization | 16,664 | 13,437 | 3,227 | 24.0 | 45,821 | 40,462 | 5,359 | 13.2 | ||||||||||||||||||||||||||||||||||||||||||
| Total depreciation and amortization | $ | 122,703 | $ | 114,729 | $ | 7,974 | 7.0 | % | $ | 360,309 | $ | 342,994 | $ | 17,315 | 5.0 | % | ||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | 2026 over 2025 | September 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Interest expense, net of interest income | $ | 37,438 | $ | 35,700 | $ | 1,738 | 4.9 | % | $ | 108,500 | $ | 108,883 | $ | (383) | (0.4) | % | ||||||||||||||||||||||||||||||||||
| Three Months Ended | Nine Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| September 30, | 2026 over 2025 | September 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Provision for income taxes | $ | 74,095 | $ | 42,027 | $ | 32,068 | 76.3 | % | $ | 156,899 | $ | 103,641 | $ | 53,258 | 51.4 | % | ||||||||||||||||||||||||||||||||||
| Effective tax rate | 26.3 | % | 26.1 | % | 0.2 | % | 26.2 | % | 25.4 | % | 0.8 | % | ||||||||||||||||||||||||||||||||||||||
| Nine Months Ended | ||||||||||||||
| September 30, | ||||||||||||||
| (in thousands) | 2026 | 2025 | ||||||||||||
| Net cash from operating activities | $ | 664,673 | $ | 511,632 | ||||||||||
| Net cash used in investing activities | (1,046,609) | (276,587) | ||||||||||||
| Net cash used in financing activities | (15,655) | (166,528) | ||||||||||||
| For the Nine Months Ended | ||||||||||||||
| September 30, | ||||||||||||||
| (in thousands) | 2026 | 2025 | ||||||||||||
| Net cash from operating activities | $ | 664,673 | $ | 511,632 | ||||||||||
| Additions to property, plant and equipment | (397,480) | (303,169) | ||||||||||||
Cash investments in strategic growth projects (1) | 107,305 | 24,340 | ||||||||||||
| Proceeds from sale and disposal of fixed assets | 8,483 | 15,250 | ||||||||||||
Adjusted free cash flow | $ | 382,981 | $ | 248,053 | ||||||||||
(in millions, except dates) | 2025 Expenditures | First Nine Months of 2026 Expenditures | 2026 Expected Expenditures | Expected Full Project Cost | Expected Completion Date | |||||||||||||||||||||||||||
| SDA unit | $30.4 | $28.4 | $50 | $210 - 220 | 2028 | |||||||||||||||||||||||||||
Fleet expansion project | — | 22.2 | 25 | 50 | 2027 | |||||||||||||||||||||||||||
| L.A. Hub | — | 54.5 | 55 | 55 | 2026 | |||||||||||||||||||||||||||
| Data center strategy investment | — | 2.1 | 15 | 70 | 2028 | |||||||||||||||||||||||||||
| (in thousands, except percentages) | September 30, 2026 | December 31, 2025 | Change | % Change | ||||||||||||||||||||||
| Closure and post-closure liabilities | $ | 140,842 | $ | 135,328 | $ | 5,514 | 4.1 | % | ||||||||||||||||||
| Remedial liabilities | 91,844 | 95,369 | (3,525) | (3.7) | ||||||||||||||||||||||
| Total environmental liabilities | $ | 232,686 | $ | 230,697 | $ | 1,989 | 0.9 | % | ||||||||||||||||||
| Period | Total Number of Shares Purchased (1) | Average Price Paid Per Share (2) | Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs | Approximate Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs (in thousands) (3) | |||||||||||||||||||
| July 1, 2026 through July 31, 2026 | 27,386 | $ | 290.26 | 17,328 | $ | 544,384 | |||||||||||||||||
| August 1, 2026 through August 31, 2026 | 65,556 | 311.52 | 64,248 | 524,384 | |||||||||||||||||||
| September 1, 2026 through September 30, 2026 | 1,428 | 313.83 | — | 524,384 | |||||||||||||||||||
| Total | 94,370 | $ | 305.25 | 81,576 | |||||||||||||||||||
| Item No. | Description | |||||||
| 4.1 | Indenture, dated October 1, 2026, among Clean Harbors, Inc., the guarantors party thereto and U.S. Bank Trust Company, National Association, as trustee (incorporated by reference to Exhibit 4.1 to the Company’s Current Report on Form 8-K filed on October 5, 2026). | |||||||
| 4.2 | Form of Note (incorporated by reference to Exhibit 4.2 to the Company’s Current Report on Form 8-K filed on October 5, 2026). | |||||||
| 31.1+ | ||||||||
| 31.2+ | ||||||||
| 31.3+ | ||||||||
| 32† | ||||||||
| 101.SCH+ | Inline XBRL Taxonomy Extension Schema Document | |||||||
| 101.CAL+ | Inline XBRL Taxonomy Extension Calculation Linkbase Document | |||||||
| 101.LAB+ | Inline XBRL Taxonomy Extension Label Linkbase Document | |||||||
| 101.PRE+ | Inline XBRL Taxonomy Extension Presentation Linkbase Document | |||||||
| 101.DEF+ | Inline XBRL Taxonomy Extension Definition Linkbase Document | |||||||
| 104+ | Cover Page Interactive Data File (formatted as inline XBRL with applicable taxonomy extension information contained in Exhibits 101) | |||||||
| CLEAN HARBORS, INC. | |||||||||||
| By: | /s/ MICHAEL L. BATTLES | ||||||||||
| Michael L. Battles | |||||||||||
| Co-Chief Executive Officer and Co-President | |||||||||||
| Date: | October 28, 2026 | ||||||||||
| By: | /s/ ERIC W. GERSTENBERG | ||||||||||
| Eric W. Gerstenberg | |||||||||||
| Co-Chief Executive Officer and Co-President | |||||||||||
| Date: | October 28, 2026 | ||||||||||
| By: | /s/ ERIC J. DUGAS | ||||||||||
| Eric J. Dugas | |||||||||||
| Executive Vice President and Chief Financial Officer | |||||||||||
| Date: | October 28, 2026 | ||||||||||
| /s/ MICHAEL L. BATTLES | |||||
| Michael L. Battles | |||||
| Co-Chief Executive Officer and Co-President | |||||
| /s/ ERIC W. GERSTENBERG | |||||
| Eric W. Gerstenberg | |||||
| Co-Chief Executive Officer and Co-President | |||||
| /s/ ERIC J. DUGAS | |||||
| Eric J. Dugas | |||||
| Executive Vice President and Chief Financial Officer | |||||
| By: | /s/ MICHAEL L. BATTLES | ||||||||||
| Michael L. Battles | |||||||||||
| Date: | October 28, 2026 | Co-Chief Executive Officer and Co-President | |||||||||
| By: | /s/ ERIC W. GERSTENBERG | ||||||||||
| Eric W. Gerstenberg | |||||||||||
| Date: | October 28, 2026 | Co-Chief Executive Officer and Co-President | |||||||||
| By: | /s/ ERIC J. DUGAS | ||||||||||
| Eric J. Dugas | |||||||||||
| Date: | October 28, 2026 | Executive Vice President and Chief Financial Officer | |||||||||