| ☒ | QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 | |||||||||||||
| FOR THE QUARTERLY PERIOD ENDED | JUNE 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. | |||||
| June 30, 2026 | December 31, 2025 | ||||||||||
| ASSETS | (unaudited) | ||||||||||
| Current assets: | |||||||||||
| Cash and cash equivalents | $ | 408,357 | $ | 826,315 | |||||||
| Short-term marketable securities | 108,361 | 127,363 | |||||||||
Accounts receivable, net of allowances aggregating $42,892 and $35,991, respectively | 1,276,620 | 1,044,137 | |||||||||
| Unbilled accounts receivable | 186,764 | 160,888 | |||||||||
| Inventories and supplies | 382,935 | 372,088 | |||||||||
| Prepaid expenses and other current assets | 109,203 | 116,452 | |||||||||
| Total current assets | 2,472,240 | 2,647,243 | |||||||||
| Property, plant and equipment, net | 2,636,955 | 2,541,067 | |||||||||
| Other assets: | |||||||||||
| Operating lease right-of-use assets | 257,518 | 255,084 | |||||||||
| Goodwill | 1,672,635 | 1,479,050 | |||||||||
| Permits and other intangibles, net | 749,111 | 653,027 | |||||||||
| Other long-term assets | 48,574 | 48,585 | |||||||||
| Total other assets | 2,727,838 | 2,435,746 | |||||||||
| Total assets | $ | 7,837,033 | $ | 7,624,056 | |||||||
| LIABILITIES AND STOCKHOLDERS’ EQUITY | |||||||||||
| Current liabilities: | |||||||||||
| Current portion of long-term debt | $ | 12,600 | $ | 12,600 | |||||||
| Accounts payable | 518,186 | 506,592 | |||||||||
| Deferred revenue | 84,038 | 81,529 | |||||||||
| Accrued expenses and other current liabilities | 442,435 | 441,788 | |||||||||
| Current portion of closure, post-closure and remedial liabilities | 22,774 | 19,112 | |||||||||
| Current portion of operating lease liabilities | 80,291 | 75,226 | |||||||||
| Total current liabilities | 1,160,324 | 1,136,847 | |||||||||
| Other liabilities: | |||||||||||
Closure and post-closure liabilities, less current portion of $13,177 and $10,290, respectively | 124,554 | 125,038 | |||||||||
Remedial liabilities, less current portion of $9,597 and $8,822, respectively | 83,512 | 86,547 | |||||||||
| Long-term debt, less current portion | 2,759,327 | 2,763,563 | |||||||||
| Operating lease liabilities, less current portion | 182,077 | 184,308 | |||||||||
| Deferred tax liabilities | 384,008 | 384,207 | |||||||||
| Other long-term liabilities | 214,809 | 197,886 | |||||||||
| Total other liabilities | 3,748,287 | 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 52,791,094 and 52,870,599 shares, respectively | 528 | 529 | |||||||||
| Additional paid-in capital | 160,100 | 193,896 | |||||||||
| Accumulated other comprehensive loss | (221,722) | (204,616) | |||||||||
| Retained earnings | 2,989,516 | 2,755,851 | |||||||||
| Total stockholders’ equity | 2,928,422 | 2,745,660 | |||||||||
| Total liabilities and stockholders’ equity | $ | 7,837,033 | $ | 7,624,056 | |||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||
| June 30, | June 30, | |||||||||||||||||||||||||
| 2026 | 2025 | 2026 | 2025 | |||||||||||||||||||||||
| Revenues: | ||||||||||||||||||||||||||
| Service revenues | $ | 1,432,855 | $ | 1,336,948 | $ | 2,680,289 | $ | 2,538,402 | ||||||||||||||||||
| Product revenues | 302,150 | 212,906 | 514,253 | 443,402 | ||||||||||||||||||||||
| Total revenues | 1,735,005 | 1,549,854 | 3,194,542 | 2,981,804 | ||||||||||||||||||||||
| Cost of revenues: (exclusive of items shown separately below) | ||||||||||||||||||||||||||
| Service revenues | 944,568 | 874,919 | 1,790,945 | 1,714,663 | ||||||||||||||||||||||
| Product revenues | 181,657 | 158,578 | 349,400 | 340,718 | ||||||||||||||||||||||
| Total cost of revenues | 1,126,225 | 1,033,497 | 2,140,345 | 2,055,381 | ||||||||||||||||||||||
| Selling, general and administrative expenses | 214,574 | 186,183 | 421,715 | 369,030 | ||||||||||||||||||||||
| Accretion of environmental liabilities | 3,502 | 3,591 | 7,044 | 7,211 | ||||||||||||||||||||||
| Depreciation and amortization | 121,807 | 116,285 | 237,606 | 228,265 | ||||||||||||||||||||||
| Income from operations | 268,897 | 210,298 | 387,832 | 321,917 | ||||||||||||||||||||||
| Other income (expense), net | 430 | (603) | (301) | (1,535) | ||||||||||||||||||||||
Interest expense, net of interest income of $3,628, $5,086, $10,041, and $10,714, respectively | (37,208) | (37,106) | (71,062) | (73,183) | ||||||||||||||||||||||
| Income before provision for income taxes | 232,119 | 172,589 | 316,469 | 247,199 | ||||||||||||||||||||||
| Provision for income taxes | 61,655 | 45,684 | 82,804 | 61,614 | ||||||||||||||||||||||
| Net income | $ | 170,464 | $ | 126,905 | $ | 233,665 | $ | 185,585 | ||||||||||||||||||
| Earnings per share: | ||||||||||||||||||||||||||
| Basic | $ | 3.23 | $ | 2.37 | $ | 4.42 | $ | 3.46 | ||||||||||||||||||
| Diluted | $ | 3.22 | $ | 2.36 | $ | 4.41 | $ | 3.44 | ||||||||||||||||||
| Shares used to compute earnings per share - Basic | 52,806 | 53,593 | 52,843 | 53,675 | ||||||||||||||||||||||
| Shares used to compute earnings per share - Diluted | 52,961 | 53,799 | 53,005 | 53,895 | ||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||
| June 30, | June 30, | |||||||||||||||||||||||||
| 2026 | 2025 | 2026 | 2025 | |||||||||||||||||||||||
| Net income | $ | 170,464 | $ | 126,905 | $ | 233,665 | $ | 185,585 | ||||||||||||||||||
| Other comprehensive (loss) income, net of tax: | ||||||||||||||||||||||||||
Unrealized (loss) gain on available-for-sale securities | (21) | 25 | (332) | 95 | ||||||||||||||||||||||
| Unrealized gain (loss) on fair value of interest rate hedges | 5,591 | (1,371) | 8,342 | (4,477) | ||||||||||||||||||||||
| Reclassification adjustment for interest rate hedge amounts realized in net income | (5,585) | (2,610) | (7,457) | (5,193) | ||||||||||||||||||||||
| Pension adjustments | 4 | (32) | 7 | (33) | ||||||||||||||||||||||
| Foreign currency translation adjustments | (8,462) | 24,026 | (17,666) | 24,714 | ||||||||||||||||||||||
| Other comprehensive (loss) income, net of tax | (8,473) | 20,038 | (17,106) | 15,106 | ||||||||||||||||||||||
| Comprehensive income | $ | 161,991 | $ | 146,943 | $ | 216,559 | $ | 200,691 | ||||||||||||||||||
| Six Months Ended | |||||||||||
| June 30, | |||||||||||
| 2026 | 2025 | ||||||||||
| Cash flows from operating activities: | |||||||||||
| Net income | $ | 233,665 | $ | 185,585 | |||||||
| Adjustments to reconcile net income to net cash from operating activities: | |||||||||||
| Depreciation and amortization | 237,606 | 228,265 | |||||||||
| Allowance for doubtful accounts | 5,951 | 3,249 | |||||||||
| Amortization of deferred financing costs and debt discount | 2,610 | 3,352 | |||||||||
| Accretion of environmental liabilities | 7,044 | 7,211 | |||||||||
| Changes in environmental liability estimates | (2,061) | (8,954) | |||||||||
Other expense, net | 301 | 1,535 | |||||||||
| Stock-based compensation | 24,396 | 13,698 | |||||||||
| Environmental expenditures | (7,079) | (7,051) | |||||||||
| Changes in assets and liabilities, net of acquisitions: | |||||||||||
| Accounts receivable and unbilled accounts receivable | (262,255) | (116,399) | |||||||||
| Inventories and supplies | (11,679) | 2,952 | |||||||||
Other current and non-current assets | 10,057 | (13,395) | |||||||||
| Accounts payable | 8,859 | (36,035) | |||||||||
| Other current and long-term liabilities | (1,945) | (54,368) | |||||||||
| Net cash from operating activities | 245,470 | 209,645 | |||||||||
| Cash flows used in investing activities: | |||||||||||
| Additions to property, plant and equipment | (224,638) | (208,724) | |||||||||
| Proceeds from sale and disposal of fixed assets | 3,694 | 4,063 | |||||||||
| Acquisitions, net of cash acquired | (357,593) | — | |||||||||
| Additions to intangible assets including costs to obtain or renew permits | (987) | (777) | |||||||||
| Purchases of available-for-sale securities | (25,853) | (45,622) | |||||||||
| Proceeds from sale of available-for-sale securities | 44,857 | 50,318 | |||||||||
| Net cash used in investing activities | (560,520) | (200,742) | |||||||||
Cash flows used in financing activities: | |||||||||||
| Change in uncashed checks | (5,507) | (2,767) | |||||||||
| Tax payments related to withholdings on vested restricted stock | (11,804) | (10,456) | |||||||||
| Repurchases of common stock | (52,133) | (67,001) | |||||||||
| Proceeds from employee stock purchase plan | 3,611 | 3,360 | |||||||||
| Deferred financing costs paid | (691) | — | |||||||||
| Payments on finance leases | (25,422) | (16,754) | |||||||||
| Principal payments on debt | (6,300) | (7,551) | |||||||||
Net cash used in financing activities | (98,246) | (101,169) | |||||||||
| Effect of exchange rate change on cash | (4,662) | 5,260 | |||||||||
Decrease in cash and cash equivalents | (417,958) | (87,006) | |||||||||
| Cash and cash equivalents, beginning of period | 826,315 | 687,192 | |||||||||
| Cash and cash equivalents, end of period | $ | 408,357 | $ | 600,186 | |||||||
| Supplemental information: | |||||||||||
| Cash payments for interest and income taxes: | |||||||||||
| Interest paid | $ | 75,394 | $ | 76,570 | |||||||
| Income taxes paid, net of refunds | 63,801 | 64,534 | |||||||||
| Non-cash investing activities: | |||||||||||
| Property, plant and equipment accrued | 40,544 | 25,156 | |||||||||
| ROU assets obtained in exchange for operating lease liabilities | 41,492 | 34,867 | |||||||||
| ROU assets obtained in exchange for finance lease liabilities | 45,495 | 57,802 | |||||||||
| 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 | ||||||||||||||||||||||||
| 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 | ||||||||||||||||||||||||
| Three Months Ended June 30, 2026 | ||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Corporate | Total | |||||||||||||||||||||||
| Primary Geographical Markets | ||||||||||||||||||||||||||
| United States | $ | 1,311,522 | $ | 259,315 | $ | — | $ | 1,570,837 | ||||||||||||||||||
| Canada | 133,010 | 31,158 | — | 164,168 | ||||||||||||||||||||||
| Total third-party revenues | $ | 1,444,532 | $ | 290,473 | $ | — | $ | 1,735,005 | ||||||||||||||||||
| Sources of Revenue | ||||||||||||||||||||||||||
| Technical Services | $ | 544,910 | $ | — | $ | — | $ | 544,910 | ||||||||||||||||||
Industrial Services and Other | 358,929 | — | — | 358,929 | ||||||||||||||||||||||
| Field and Emergency Response Services | 249,020 | — | — | 249,020 | ||||||||||||||||||||||
| Safety-Kleen Environmental Services | 291,673 | 87,738 | — | 379,411 | ||||||||||||||||||||||
| Safety-Kleen Oil | — | 202,735 | — | 202,735 | ||||||||||||||||||||||
| Total third-party revenues | $ | 1,444,532 | $ | 290,473 | $ | — | $ | 1,735,005 | ||||||||||||||||||
| Three Months Ended June 30, 2025 | ||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Corporate | Total | |||||||||||||||||||||||
| Primary Geographical Markets | ||||||||||||||||||||||||||
| United States | $ | 1,208,770 | $ | 194,110 | $ | 89 | $ | 1,402,969 | ||||||||||||||||||
| Canada | 121,289 | 25,596 | — | 146,885 | ||||||||||||||||||||||
| Total third-party revenues | $ | 1,330,059 | $ | 219,706 | $ | 89 | $ | 1,549,854 | ||||||||||||||||||
| Sources of Revenue | ||||||||||||||||||||||||||
| Technical Services | $ | 463,421 | $ | — | $ | — | $ | 463,421 | ||||||||||||||||||
Industrial Services and Other | 361,580 | — | 89 | 361,669 | ||||||||||||||||||||||
| Field and Emergency Response Services | 242,791 | — | — | 242,791 | ||||||||||||||||||||||
| Safety-Kleen Environmental Services | 262,267 | 72,463 | — | 334,730 | ||||||||||||||||||||||
| Safety-Kleen Oil | — | 147,243 | — | 147,243 | ||||||||||||||||||||||
| Total third-party revenues | $ | 1,330,059 | $ | 219,706 | $ | 89 | $ | 1,549,854 | ||||||||||||||||||
| Six Months Ended June 30, 2026 | ||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Corporate | Total | |||||||||||||||||||||||
| Primary Geographical Markets | ||||||||||||||||||||||||||
| United States | $ | 2,462,630 | $ | 459,588 | $ | — | $ | 2,922,218 | ||||||||||||||||||
| Canada | 224,350 | 47,974 | — | 272,324 | ||||||||||||||||||||||
| Total third-party revenues | $ | 2,686,980 | $ | 507,562 | $ | — | $ | 3,194,542 | ||||||||||||||||||
| Sources of Revenue | ||||||||||||||||||||||||||
| Technical Services | $ | 993,942 | $ | — | $ | — | $ | 993,942 | ||||||||||||||||||
Industrial Services and Other | 661,669 | — | — | 661,669 | ||||||||||||||||||||||
| Field and Emergency Response Services | 479,270 | — | — | 479,270 | ||||||||||||||||||||||
| Safety-Kleen Environmental Services | 552,099 | 165,468 | — | 717,567 | ||||||||||||||||||||||
| Safety-Kleen Oil | — | 342,094 | — | 342,094 | ||||||||||||||||||||||
| Total third-party revenues | $ | 2,686,980 | $ | 507,562 | $ | — | $ | 3,194,542 | ||||||||||||||||||
| Six Months Ended June 30, 2025 | ||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Corporate | Total | |||||||||||||||||||||||
| Primary Geographical Markets | ||||||||||||||||||||||||||
| United States | $ | 2,325,037 | $ | 394,129 | $ | 186 | $ | 2,719,352 | ||||||||||||||||||
| Canada | 212,060 | 50,392 | — | 262,452 | ||||||||||||||||||||||
| Total third-party revenues | $ | 2,537,097 | $ | 444,521 | $ | 186 | $ | 2,981,804 | ||||||||||||||||||
| Sources of Revenue | ||||||||||||||||||||||||||
| Technical Services | $ | 889,626 | $ | — | $ | — | $ | 889,626 | ||||||||||||||||||
Industrial Services and Other | 683,938 | — | 186 | 684,124 | ||||||||||||||||||||||
| Field and Emergency Response Services | 458,493 | — | — | 458,493 | ||||||||||||||||||||||
| Safety-Kleen Environmental Services | 505,040 | 137,364 | — | 642,404 | ||||||||||||||||||||||
| Safety-Kleen Oil | — | 307,157 | — | 307,157 | ||||||||||||||||||||||
| Total third-party revenues | $ | 2,537,097 | $ | 444,521 | $ | 186 | $ | 2,981,804 | ||||||||||||||||||
| (in thousands) | June 30, 2026 | December 31, 2025 | ||||||||||||
| Receivables | $ | 1,276,620 | $ | 1,044,137 | ||||||||||
| Contract assets (unbilled receivables) | 186,764 | 160,888 | ||||||||||||
| Contract liabilities (deferred revenue) | 84,038 | 81,529 | ||||||||||||
At May 13, 2026 | |||||
| Accounts receivable, including unbilled receivables | $ | 6,855 | |||
| Inventories and supplies | 148 | ||||
| Prepaid expenses and other current assets | 1,844 | ||||
| Property, plant and equipment | 18,781 | ||||
| Permits and other intangible assets | 91,400 | ||||
| Operating lease right-of-use assets | 160 | ||||
| Other long-term assets | 10 | ||||
| Accounts payable | (3,225) | ||||
| Accrued expenses and other current liabilities | (796) | ||||
| Current portion of operating lease liabilities | (118) | ||||
| Operating lease liabilities, less current portion | (42) | ||||
| Total identifiable net assets | 115,017 | ||||
| Goodwill | 110,756 | ||||
| Total purchase price | $ | 225,773 | |||
| At Acquisition Date As Reported March 31, 2026 | Measurement Period Adjustments | At Acquisition Date As Reported June 30, 2026 | |||||||||||||||
| Inventories and supplies | $ | 177 | $ | — | $ | 177 | |||||||||||
| Property, plant and equipment | 15,000 | (1,614) | 13,386 | ||||||||||||||
| Permits and other intangible assets | 40,000 | (6,200) | 33,800 | ||||||||||||||
| Operating lease right-of-use assets | 5,634 | — | 5,634 | ||||||||||||||
| Accrued expenses and other current liabilities | (180) | — | (180) | ||||||||||||||
| Current portion of operating lease liabilities | (1,128) | — | (1,128) | ||||||||||||||
| Operating lease liabilities, less current portion | (4,506) | — | (4,506) | ||||||||||||||
| Total identifiable net assets | 54,997 | (7,814) | 47,183 | ||||||||||||||
| Goodwill | 76,823 | 7,814 | 84,637 | ||||||||||||||
| Total purchase price | $ | 131,820 | $ | — | $ | 131,820 | |||||||||||
| June 30, 2026 | December 31, 2025 | ||||||||||
| Supplies | $ | 221,142 | $ | 217,028 | |||||||
| Oil and oil related products | 128,467 | 123,883 | |||||||||
| Solvent and solutions | 13,379 | 11,589 | |||||||||
| Other | 19,947 | 19,588 | |||||||||
| Total inventories and supplies | $ | 382,935 | $ | 372,088 | |||||||
| June 30, 2026 | December 31, 2025 | ||||||||||
| Land | $ | 198,839 | $ | 193,438 | |||||||
| Asset retirement costs (non-landfill) | 40,065 | 40,232 | |||||||||
| Landfill assets | 282,066 | 278,700 | |||||||||
Buildings and improvements (1) | 765,986 | 753,404 | |||||||||
Vehicles (2) | 1,665,439 | 1,583,387 | |||||||||
Equipment (3) | 2,713,543 | 2,652,027 | |||||||||
| Construction in progress | 136,555 | 90,182 | |||||||||
| 5,802,493 | 5,591,370 | ||||||||||
| Less - accumulated depreciation and amortization | 3,165,538 | 3,050,303 | |||||||||
| Total property, plant and equipment, net | $ | 2,636,955 | $ | 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 | 195,393 | — | 195,393 | ||||||||||||||
| Foreign currency translation | (1,283) | (525) | (1,808) | ||||||||||||||
| Balance at June 30, 2026 | $ | 1,491,588 | $ | 181,047 | $ | 1,672,635 | |||||||||||
| June 30, 2026 | December 31, 2025 | ||||||||||||||||||||||||||||||||||
| Cost | Accumulated Amortization | Net | Cost | Accumulated Amortization | Net | ||||||||||||||||||||||||||||||
| Permits | $ | 195,809 | $ | 135,362 | $ | 60,447 | $ | 196,224 | $ | 132,308 | $ | 63,916 | |||||||||||||||||||||||
Customer and supplier relationships | 804,861 | 294,037 | 510,824 | 698,381 | 292,813 | 405,568 | |||||||||||||||||||||||||||||
Other intangible assets | 120,942 | 62,710 | 58,232 | 121,030 | 57,438 | 63,592 | |||||||||||||||||||||||||||||
Total amortizable permits and other intangible assets | 1,121,612 | 492,109 | 629,503 | 1,015,635 | 482,559 | 533,076 | |||||||||||||||||||||||||||||
Trademarks and trade names | 119,608 | — | 119,608 | 119,951 | — | 119,951 | |||||||||||||||||||||||||||||
Total permits and other intangible assets | $ | 1,241,220 | $ | 492,109 | $ | 749,111 | $ | 1,135,586 | $ | 482,559 | $ | 653,027 | |||||||||||||||||||||||
| Years Ending December 31, | Expected Amortization | ||||
| 2026 (six months) | $ | 32,195 | |||
| 2027 | 59,362 | ||||
| 2028 | 57,996 | ||||
| 2029 | 56,919 | ||||
| 2030 | 46,444 | ||||
| Thereafter | 376,587 | ||||
| $ | 629,503 | ||||
| June 30, 2026 | December 31, 2025 | ||||||||||
| Accrued insurance | $ | 125,157 | $ | 116,675 | |||||||
| Accrued compensation and benefits | 117,605 | 144,689 | |||||||||
| Accrued income, real estate, sales and other taxes | 57,273 | 42,082 | |||||||||
| Accrued interest | 30,157 | 30,893 | |||||||||
| Accrued other | 112,243 | 107,449 | |||||||||
| $ | 442,435 | $ | 441,788 | ||||||||
| Landfill Retirement Liability | Non-Landfill Retirement Liability | Total | |||||||||||||||
| Balance at January 1, 2026 | $ | 59,763 | $ | 75,565 | $ | 135,328 | |||||||||||
| New asset retirement obligations | 2,129 | — | 2,129 | ||||||||||||||
| Accretion | 2,439 | 2,830 | 5,269 | ||||||||||||||
| Changes in estimates recorded to consolidated statement of operations | (1,934) | (998) | (2,932) | ||||||||||||||
| Changes in estimates recorded to consolidated balance sheet | — | 366 | 366 | ||||||||||||||
| Expenditures | (1,393) | (230) | (1,623) | ||||||||||||||
| Currency translation and other | (104) | (702) | (806) | ||||||||||||||
| Balance at June 30, 2026 | $ | 60,900 | $ | 76,831 | $ | 137,731 | |||||||||||
| 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 | 47 | 1,141 | 587 | 1,775 | |||||||||||||||||||
| Changes in estimates recorded to consolidated statement of operations | 12 | 498 | 361 | 871 | |||||||||||||||||||
| Expenditures | (24) | (2,796) | (2,636) | (5,456) | |||||||||||||||||||
| Currency translation and other | — | — | 550 | 550 | |||||||||||||||||||
| Balance at June 30, 2026 | $ | 1,963 | $ | 53,366 | $ | 37,780 | $ | 93,109 | |||||||||||||||
| June 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”) | $ | 1,241,100 | $ | 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 | |||||||||
| Long-term debt, at par | $ | 2,786,100 | $ | 2,792,400 | |||||||
| Unamortized debt issuance costs and discount, net | (26,773) | (28,837) | |||||||||
| Long-term debt, at carrying value | $ | 2,759,327 | $ | 2,763,563 | |||||||
| Three Months Ended June 30, | Six Months Ended June 30, | ||||||||||||||||||||||
| 2026 | 2025 | 2026 | 2025 | ||||||||||||||||||||
| Numerator for basic and diluted earnings per share: | |||||||||||||||||||||||
| Net income | $ | 170,464 | $ | 126,905 | $ | 233,665 | $ | 185,585 | |||||||||||||||
| Denominator: | |||||||||||||||||||||||
| Weighted-average shares outstanding, basic | 52,806 | 53,593 | 52,843 | 53,675 | |||||||||||||||||||
| Dilutive impact of equity awards | 155 | 206 | 162 | 220 | |||||||||||||||||||
Weighted-average shares outstanding, diluted | 52,961 | 53,799 | 53,005 | 53,895 | |||||||||||||||||||
| Basic earnings per share: | $ | 3.23 | $ | 2.37 | $ | 4.42 | $ | 3.46 | |||||||||||||||
| Diluted earnings per share: | $ | 3.22 | $ | 2.36 | $ | 4.41 | $ | 3.44 | |||||||||||||||
| 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 | (17,666) | (415) | 6,319 | 7 | (11,755) | ||||||||||||||||||||||||
| Amounts reclassified out of accumulated other comprehensive loss | — | — | (5,113) | — | (5,113) | ||||||||||||||||||||||||
| Tax benefit (provision) | — | 83 | (321) | — | (238) | ||||||||||||||||||||||||
| Other comprehensive (loss) income | (17,666) | (332) | 885 | 7 | (17,106) | ||||||||||||||||||||||||
| Balance at June 30, 2026 | $ | (232,180) | $ | (175) | $ | 10,818 | $ | (185) | $ | (221,722) | |||||||||||||||||||
| Component of Accumulated Other Comprehensive Loss | Three Months Ended June 30, 2026 | Six Months Ended June 30, 2026 | Location | |||||||||||||||||
| Unrealized Gain on Fair Value of Interest Rate Hedges | $ | 2,548 | $ | 5,113 | 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 | 71,563 | 266.07 | |||||||||
| Vested | (104,930) | 167.73 | |||||||||
| Forfeited | (9,498) | 190.33 | |||||||||
| Balance at June 30, 2026 | 270,955 | $ | 202.56 | ||||||||
| Performance Stock | Number of Shares | Weighted Average Grant-Date Fair Value | |||||||||
| Balance at January 1, 2026 | 147,404 | $ | 182.63 | ||||||||
| Granted | 82,793 | 259.98 | |||||||||
| Vested | (14,031) | 114.61 | |||||||||
Forfeited (1) | (38,392) | 181.91 | |||||||||
| Balance at June 30, 2026 | 177,774 | $ | 224.17 | ||||||||
| For the Three Months Ended June 30, 2026 | |||||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Segment Revenues | Corporate | Total Consolidated Revenues | |||||||||||||||||||||||||
| Third-party revenues | $ | 1,444,532 | $ | 290,473 | $ | 1,735,005 | $ | — | $ | 1,735,005 | |||||||||||||||||||
| Intersegment revenues (expense), net | 12,031 | (12,031) | — | — | — | ||||||||||||||||||||||||
| Direct revenues | $ | 1,456,563 | $ | 278,442 | $ | 1,735,005 | $ | — | $ | 1,735,005 | |||||||||||||||||||
| For the Three Months Ended June 30, 2025 | |||||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Segment Revenues | Corporate | Total Consolidated Revenues | |||||||||||||||||||||||||
| Third-party revenues | $ | 1,330,059 | $ | 219,706 | $ | 1,549,765 | $ | 89 | $ | 1,549,854 | |||||||||||||||||||
| Intersegment revenues (expense), net | 21,976 | (21,976) | — | — | — | ||||||||||||||||||||||||
| Direct revenues | $ | 1,352,035 | $ | 197,730 | $ | 1,549,765 | $ | 89 | $ | 1,549,854 | |||||||||||||||||||
| For the Six Months Ended June 30, 2026 | |||||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Segment Revenues | Corporate | Total Consolidated Revenues | |||||||||||||||||||||||||
| Third-party revenues | $ | 2,686,980 | $ | 507,562 | $ | 3,194,542 | $ | — | $ | 3,194,542 | |||||||||||||||||||
| Intersegment revenues (expense), net | 22,109 | (22,109) | — | — | — | ||||||||||||||||||||||||
| Direct revenues | $ | 2,709,089 | $ | 485,453 | $ | 3,194,542 | $ | — | $ | 3,194,542 | |||||||||||||||||||
| For the Six Months Ended June 30, 2025 | |||||||||||||||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Segment Revenues | Corporate | Total Consolidated Revenues | |||||||||||||||||||||||||
| Third-party revenues | $ | 2,537,097 | $ | 444,521 | $ | 2,981,618 | $ | 186 | $ | 2,981,804 | |||||||||||||||||||
| Intersegment revenues (expense), net | 24,051 | (24,051) | — | — | — | ||||||||||||||||||||||||
| Direct revenues | $ | 2,561,148 | $ | 420,470 | $ | 2,981,618 | $ | 186 | $ | 2,981,804 | |||||||||||||||||||
| For the Three Months Ended June 30, 2026 | |||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Reportable Segments | |||||||||||||||
| Direct Revenues | $ | 1,456,563 | $ | 278,442 | $ | 1,735,005 | |||||||||||
| Cost of Revenues | 943,730 | 162,639 | 1,106,369 | ||||||||||||||
| Selling, General and Administrative Expenses | 106,729 | 22,810 | 129,539 | ||||||||||||||
| Total Reportable Segment Adjusted EBITDA | $ | 406,104 | $ | 92,993 | $ | 499,097 | |||||||||||
| For the Three Months Ended June 30, 2025 | |||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Reportable Segments | |||||||||||||||
| Direct Revenues | $ | 1,352,035 | $ | 197,730 | $ | 1,549,765 | |||||||||||
| Cost of Revenues | 880,871 | 140,567 | 1,021,438 | ||||||||||||||
| Selling, General and Administrative Expenses | 94,970 | 18,850 | 113,820 | ||||||||||||||
| Total Reportable Segment Adjusted EBITDA | $ | 376,194 | $ | 38,313 | $ | 414,507 | |||||||||||
| For the Six Months Ended June 30, 2026 | |||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Reportable Segments | |||||||||||||||
| Direct Revenues | $ | 2,709,089 | $ | 485,453 | $ | 3,194,542 | |||||||||||
| Cost of Revenues | 1,796,110 | 317,275 | 2,113,385 | ||||||||||||||
| Selling, General and Administrative Expenses | 216,474 | 42,204 | 258,678 | ||||||||||||||
| Total Reportable Segment Adjusted EBITDA | $ | 696,505 | $ | 125,974 | $ | 822,479 | |||||||||||
| For the Six Months Ended June 30, 2025 | |||||||||||||||||
| Environmental Services | Safety-Kleen Sustainability Solutions | Total Reportable Segments | |||||||||||||||
| Direct Revenues | $ | 2,561,148 | $ | 420,470 | $ | 2,981,618 | |||||||||||
| Cost of Revenues | 1,720,813 | 318,005 | 2,038,818 | ||||||||||||||
| Selling, General and Administrative Expenses | 189,550 | 35,900 | 225,450 | ||||||||||||||
| Total Reportable Segment Adjusted EBITDA | $ | 650,785 | $ | 66,565 | $ | 717,350 | |||||||||||
| Three Months Ended | Six Months Ended | ||||||||||||||||||||||
| June 30, | June 30, | ||||||||||||||||||||||
| 2026 | 2025 | 2026 | 2025 | ||||||||||||||||||||
| Adjusted EBITDA: | |||||||||||||||||||||||
| Environmental Services | $ | 406,104 | $ | 376,194 | $ | 696,505 | $ | 650,785 | |||||||||||||||
| Safety-Kleen Sustainability Solutions | 92,993 | 38,313 | 125,974 | 66,565 | |||||||||||||||||||
| Total Reportable Segment Adjusted EBITDA | 499,097 | 414,507 | 822,479 | 717,350 | |||||||||||||||||||
| Reconciliation to Consolidated Statements of Operations: | |||||||||||||||||||||||
Corporate Costs(1) | 90,073 | 78,270 | 165,601 | 146,259 | |||||||||||||||||||
| Accretion of environmental liabilities | 3,502 | 3,591 | 7,044 | 7,211 | |||||||||||||||||||
| Stock-based compensation | 14,818 | 6,063 | 24,396 | 13,698 | |||||||||||||||||||
| Depreciation and amortization | 121,807 | 116,285 | 237,606 | 228,265 | |||||||||||||||||||
| Income from operations | 268,897 | 210,298 | 387,832 | 321,917 | |||||||||||||||||||
| Other (income) expense, net | (430) | 603 | 301 | 1,535 | |||||||||||||||||||
| Interest expense, net of interest income | 37,208 | 37,106 | 71,062 | 73,183 | |||||||||||||||||||
| Income from operations before provision for income taxes | $ | 232,119 | $ | 172,589 | $ | 316,469 | $ | 247,199 | |||||||||||||||
| Summary of Operations | |||||||||||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | June 30, | ||||||||||||||||||||||||||||||||||||||||||||||
| 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||
Direct Revenues (1): | |||||||||||||||||||||||||||||||||||||||||||||||
| Environmental Services | $ | 1,456,563 | $ | 1,352,035 | $ | 104,528 | 7.7% | $ | 2,709,089 | $ | 2,561,148 | $ | 147,941 | 5.8% | |||||||||||||||||||||||||||||||||
| Safety-Kleen Sustainability Solutions | 278,442 | 197,730 | 80,712 | 40.8 | 485,453 | 420,470 | 64,983 | 15.5 | |||||||||||||||||||||||||||||||||||||||
Corporate | — | 89 | (89) | N/M | — | 186 | (186) | N/M | |||||||||||||||||||||||||||||||||||||||
| Total | 1,735,005 | 1,549,854 | 185,151 | 11.9 | 3,194,542 | 2,981,804 | 212,738 | 7.1 | |||||||||||||||||||||||||||||||||||||||
Cost of Revenues (2): | |||||||||||||||||||||||||||||||||||||||||||||||
| Environmental Services | 943,730 | 880,871 | 62,859 | 7.1 | 1,796,110 | 1,720,813 | 75,297 | 4.4 | |||||||||||||||||||||||||||||||||||||||
| Safety-Kleen Sustainability Solutions | 162,639 | 140,567 | 22,072 | 15.7 | 317,275 | 318,005 | (730) | (0.2) | |||||||||||||||||||||||||||||||||||||||
Corporate | 19,856 | 12,059 | 7,797 | N/M | 26,960 | 16,563 | 10,397 | N/M | |||||||||||||||||||||||||||||||||||||||
| Total | 1,126,225 | 1,033,497 | 92,728 | 9.0 | 2,140,345 | 2,055,381 | 84,964 | 4.1 | |||||||||||||||||||||||||||||||||||||||
Selling, General & Administrative Expenses (3): | |||||||||||||||||||||||||||||||||||||||||||||||
| Environmental Services | 106,729 | 94,970 | 11,759 | 12.4 | 216,474 | 189,550 | 26,924 | 14.2 | |||||||||||||||||||||||||||||||||||||||
| Safety-Kleen Sustainability Solutions | 22,810 | 18,850 | 3,960 | 21.0 | 42,204 | 35,900 | 6,304 | 17.6 | |||||||||||||||||||||||||||||||||||||||
Corporate | 70,217 | 66,300 | 3,917 | 5.9 | 138,641 | 129,882 | 8,759 | 6.7 | |||||||||||||||||||||||||||||||||||||||
| Total | 199,756 | 180,120 | 19,636 | 10.9 | 397,319 | 355,332 | 41,987 | 11.8 | |||||||||||||||||||||||||||||||||||||||
| Adjusted EBITDA: | |||||||||||||||||||||||||||||||||||||||||||||||
| Environmental Services | 406,104 | 376,194 | 29,910 | 8.0 | 696,505 | 650,785 | 45,720 | 7.0 | |||||||||||||||||||||||||||||||||||||||
| Safety-Kleen Sustainability Solutions | 92,993 | 38,313 | 54,680 | 142.7 | 125,974 | 66,565 | 59,409 | 89.2 | |||||||||||||||||||||||||||||||||||||||
Corporate | (90,073) | (78,270) | (11,803) | (15.1) | (165,601) | (146,259) | (19,342) | (13.2) | |||||||||||||||||||||||||||||||||||||||
| Total | $ | 409,024 | $ | 336,237 | $ | 72,787 | 21.6% | $ | 656,878 | $ | 571,091 | $ | 85,787 | 15.0% | |||||||||||||||||||||||||||||||||
| Adjusted EBITDA as a % of Direct Revenues: | |||||||||||||||||||||||||||||||||||||||||||||||
Environmental Services (4) | 27.9 | % | 27.8 | % | 0.1 | % | 25.7 | % | 25.4 | % | 0.3 | % | |||||||||||||||||||||||||||||||||||
Safety-Kleen Sustainability Solutions (4) | 33.4 | % | 19.4 | % | 14.0 | % | 25.9 | % | 15.8 | % | 10.1 | % | |||||||||||||||||||||||||||||||||||
Corporate (5) | (5.2) | % | (5.1) | % | (0.1) | % | (5.2) | % | (4.9) | % | (0.3) | % | |||||||||||||||||||||||||||||||||||
| Total | 23.6 | % | 21.7 | % | 1.9 | % | 20.6 | % | 19.2 | % | 1.4 | % | |||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | 2026 over 2025 | June 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Direct revenues | $ | 1,456,563 | $ | 1,352,035 | $ | 104,528 | 7.7 | % | $ | 2,709,089 | $ | 2,561,148 | $ | 147,941 | 5.8 | % | ||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | 2026 over 2025 | June 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Direct revenues | $ | 278,442 | $ | 197,730 | $ | 80,712 | 40.8 | % | $ | 485,453 | $ | 420,470 | $ | 64,983 | 15.5 | % | ||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | 2026 over 2025 | June 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Cost of revenues | $ | 943,730 | $ | 880,871 | $ | 62,859 | 7.1 | % | $ | 1,796,110 | $ | 1,720,813 | $ | 75,297 | 4.4 | % | ||||||||||||||||||||||||||||||||||
| As a % of Direct revenues | 64.8 | % | 65.2 | % | (0.4) | % | 66.3 | % | 67.2 | % | (0.9) | % | ||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | 2026 over 2025 | June 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Cost of revenues | $ | 162,639 | $ | 140,567 | $ | 22,072 | 15.7 | % | $ | 317,275 | $ | 318,005 | $ | (730) | (0.2) | % | ||||||||||||||||||||||||||||||||||
| As a % of Direct revenues | 58.4 | % | 71.1 | % | (12.7) | % | 65.4 | % | 75.6 | % | (10.2) | % | ||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | 2026 over 2025 | June 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| SG&A expenses | $ | 106,729 | $ | 94,970 | $ | 11,759 | 12.4 | % | $ | 216,474 | $ | 189,550 | $ | 26,924 | 14.2 | % | ||||||||||||||||||||||||||||||||||
| As a % of Direct revenues | 7.3 | % | 7.0 | % | 0.3 | % | 8.0 | % | 7.4 | % | 0.6 | % | ||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | 2026 over 2025 | June 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| SG&A expenses | $ | 22,810 | $ | 18,850 | $ | 3,960 | 21.0 | % | $ | 42,204 | $ | 35,900 | $ | 6,304 | 17.6 | % | ||||||||||||||||||||||||||||||||||
| As a % of Direct revenues | 8.2 | % | 9.5 | % | (1.3) | % | 8.7 | % | 8.5 | % | 0.2 | % | ||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | 2026 over 2025 | June 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| SG&A expenses | $ | 70,217 | $ | 66,300 | $ | 3,917 | 5.9 | % | $ | 138,641 | $ | 129,882 | $ | 8,759 | 6.7 | % | ||||||||||||||||||||||||||||||||||
| As a % of Total Company Direct revenues | 4.0 | % | 4.3 | % | (0.3) | % | 4.3 | % | 4.4 | % | (0.1) | % | ||||||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||
| June 30, | June 30, | |||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | 2026 | 2025 | ||||||||||||||||||||||
| Net income | $ | 170,464 | $ | 126,905 | $ | 233,665 | $ | 185,585 | ||||||||||||||||||
| Accretion of environmental liabilities | 3,502 | 3,591 | 7,044 | 7,211 | ||||||||||||||||||||||
| Stock-based compensation | 14,818 | 6,063 | 24,396 | 13,698 | ||||||||||||||||||||||
| Depreciation and amortization | 121,807 | 116,285 | 237,606 | 228,265 | ||||||||||||||||||||||
| Other (income) expense, net | (430) | 603 | 301 | 1,535 | ||||||||||||||||||||||
| Interest expense, net of interest income | 37,208 | 37,106 | 71,062 | 73,183 | ||||||||||||||||||||||
| Provision for income taxes | 61,655 | 45,684 | 82,804 | 61,614 | ||||||||||||||||||||||
| Adjusted EBITDA | $ | 409,024 | $ | 336,237 | $ | 656,878 | $ | 571,091 | ||||||||||||||||||
| As a % of direct revenues | 23.6 | % | 21.7 | % | 20.6 | % | 19.2 | % | ||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | 2026 over 2025 | June 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 | $ | 106,324 | $ | 102,573 | $ | 3,751 | 3.7 | % | $ | 208,449 | $ | 201,240 | $ | 7,209 | 3.6 | % | ||||||||||||||||||||||||||||||||||
| Permits and other intangibles amortization | 15,483 | 13,712 | 1,771 | 12.9 | 29,157 | 27,025 | 2,132 | 7.9 | ||||||||||||||||||||||||||||||||||||||||||
| Total depreciation and amortization | $ | 121,807 | $ | 116,285 | $ | 5,522 | 4.7 | % | $ | 237,606 | $ | 228,265 | $ | 9,341 | 4.1 | % | ||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | 2026 over 2025 | June 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Interest expense, net of interest income | $ | 37,208 | $ | 37,106 | $ | 102 | 0.3 | % | $ | 71,062 | $ | 73,183 | $ | (2,121) | (2.9) | % | ||||||||||||||||||||||||||||||||||
| Three Months Ended | Six Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
| June 30, | 2026 over 2025 | June 30, | 2026 over 2025 | |||||||||||||||||||||||||||||||||||||||||||||||
| (in thousands, except percentages) | 2026 | 2025 | Change | % Change | 2026 | 2025 | Change | % Change | ||||||||||||||||||||||||||||||||||||||||||
| Provision for income taxes | $ | 61,655 | $ | 45,684 | $ | 15,971 | 35.0 | % | $ | 82,804 | $ | 61,614 | $ | 21,190 | 34.4 | % | ||||||||||||||||||||||||||||||||||
| Effective tax rate | 26.6 | % | 26.5 | % | 0.1 | % | 26.2 | % | 24.9 | % | 1.3 | % | ||||||||||||||||||||||||||||||||||||||
| Six Months Ended | ||||||||||||||
| June 30, | ||||||||||||||
| (in thousands) | 2026 | 2025 | ||||||||||||
| Net cash from operating activities | $ | 245,470 | $ | 209,645 | ||||||||||
| Net cash used in investing activities | (560,520) | (200,742) | ||||||||||||
| Net cash used in financing activities | (98,246) | (101,169) | ||||||||||||
| For the Six Months Ended | ||||||||||||||
| June 30, | ||||||||||||||
| (in thousands) | 2026 | 2025 | ||||||||||||
| Net cash from operating activities | $ | 245,470 | $ | 209,645 | ||||||||||
| Additions to property, plant and equipment | (224,638) | (208,724) | ||||||||||||
Cash investments in strategic growth projects (1) | 35,322 | 12,436 | ||||||||||||
| Proceeds from sale and disposal of fixed assets | 3,694 | 4,063 | ||||||||||||
Adjusted free cash flow | $ | 59,848 | $ | 17,420 | ||||||||||
(in millions, except dates) | 2025 Expenditures | First Six Months of 2026 Expenditures | 2026 Expected Expenditures | Expected Full Project Cost | Expected Completion Date | |||||||||||||||||||||||||||
| SDA unit | $30.4 | $17.8 | $85 | $210 - 220 | 2028 | |||||||||||||||||||||||||||
Fleet expansion project | — | 17.5 | 25 | 50 | 2027 | |||||||||||||||||||||||||||
| Data center strategy investment | — | — | 10 | 50 | 2028 | |||||||||||||||||||||||||||
| (in thousands, except percentages) | June 30, 2026 | December 31, 2025 | Change | % Change | ||||||||||||||||||||||
| Closure and post-closure liabilities | $ | 137,731 | $ | 135,328 | $ | 2,403 | 1.8 | % | ||||||||||||||||||
| Remedial liabilities | 93,109 | 95,369 | (2,260) | (2.4) | ||||||||||||||||||||||
| Total environmental liabilities | $ | 230,840 | $ | 230,697 | $ | 143 | 0.1 | % | ||||||||||||||||||
| 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) | |||||||||||||||||||
| April 1, 2026 through April 30, 2026 | 4,665 | $ | 290.04 | — | $ | 574,384 | |||||||||||||||||
| May 1, 2026 through May 31, 2026 | 85,000 | 297.70 | 84,023 | 549,384 | |||||||||||||||||||
| June 1, 2026 through June 30, 2026 | 3,000 | 281.00 | — | 549,384 | |||||||||||||||||||
| Total | 92,665 | $ | 296.77 | 84,023 | |||||||||||||||||||
| Item No. | Description | |||||||
| 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: | July 29, 2026 | ||||||||||
| By: | /s/ ERIC W. GERSTENBERG | ||||||||||
| Eric W. Gerstenberg | |||||||||||
| Co-Chief Executive Officer and Co-President | |||||||||||
| Date: | July 29, 2026 | ||||||||||
| By: | /s/ ERIC J. DUGAS | ||||||||||
| Eric J. Dugas | |||||||||||
| Executive Vice President and Chief Financial Officer | |||||||||||
| Date: | July 29, 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: | July 29, 2026 | Co-Chief Executive Officer and Co-President | |||||||||
| By: | /s/ ERIC W. GERSTENBERG | ||||||||||
| Eric W. Gerstenberg | |||||||||||
| Date: | July 29, 2026 | Co-Chief Executive Officer and Co-President | |||||||||
| By: | /s/ ERIC J. DUGAS | ||||||||||
| Eric J. Dugas | |||||||||||
| Date: | July 29, 2026 | Executive Vice President and Chief Financial Officer | |||||||||