Demand for Clean Harbors’ (NYSE: CLH) disposal and recycling network drove a record second quarter for the Norwell, Massachusetts-based environmental services provider.
The company cited healthy volumes, along with remediation and PFAS-related project work, as the primary driver of its Environmental Services segment’s results.
Clean Harbors reported $1.74 billion in second-quarter revenue, up 12% from $1.55 billion in Q2 2025.
“Our record second-quarter results demonstrate the substantial momentum we achieved in both of our operating segments,” said Mike Battles, Co-CEO.
Battles pointed to the disposal and recycling network’s volumes, along with pricing initiatives to offset inflation and fuel costs, as key contributors within Environmental Services.
Segment growth
The company’s Environmental Services segment generated $1.46 billion in direct revenue for the quarter, up from $1.35 billion a year earlier.
Clean Harbors’ Environmental Services segment spans the company’s core disposal and recycling infrastructure, including Technical Services (hazardous waste incineration, landfill disposal and recycling), Safety-Kleen Environmental Services (containerized waste collection, vacuum services and parts washers), Field Services (emergency response and on-site industrial cleaning) and Industrial Services.
The segment also houses Clean Harbors’ newly introduced data center offering, which includes mechanical flushing, chemical passivation and water filtration services.
The segment’s adjusted EBITDA rose to $406.1 million from $376.2 million, with margin up to 27.9% from 27.8%. This is the 17th consecutive quarter of year-over-year margin expansion and the 19th straight quarter of EBITDA growth for the segment, according to Co-CEO Eric Gerstenberg.
“With ES, demand for our disposal assets and vast collection network remain strong, reflecting the scarcity of disposal capacity across the industry,” Gerstenberg told analysts on the company’s earnings call.
Technical Services revenue grew 18% on demand for disposal and recycling services, including a large PFAS-related filtration project that stemmed from earlier emergency response work; Gerstenberg said that project alone accounted for more than $30 million of Q2 revenue.
Safety-Kleen Environmental Services revenue within the segment rose 11% on pricing and growth in containerized waste collection and vacuum services, with the unit performing 236,000 parts washer services during the quarter. Gerstenberg attributed the growth roughly 60% to pricing and 40% to volume, and said the company is “certainly getting tighter with customers” and taking market share in the business.
Incineration utilization, including the newly ramping Kimball incinerator, reached 91%, up from 86% in the second quarter of 2025, while landfill volumes rose 7% year over year. Field Services revenue grew 3%, a comparison Gerstenberg called difficult given large emergency response projects in the prior-year period.
SKSS results
For the company’s re-refining and used oil segment, Safety Kleen Sustainability Solutions , revenue jumped 41% to $278.4 million from $197.7 million in Q2 2025, and adjusted EBITDA more than doubled, up 143% to $93 million from $38.3 million, with segment margin up more than 70% from a year earlier.
Battles attributed the results to global supply disruptions in refined products out of the Middle East and Asia, along with the company’s push into Group III base oil production and blended volume sales.
Clean Harbors collected 61 million gallons of waste oil in the quarter, down from 64 million gallons in the second quarter of 2025, while growing revenue from its used oil collection services. Battles said the collections team actively managed both volumes and costs on the front end of the re-refining spread, and that current supply conditions are expected to extend into the third quarter.
CFO Eric Dugas said the company’s “consolidated Q2 adjusted EBITDA margin was 23.6%, representing the highest quarterly margin in our company’s history.”
Contracts and M&A
Clean Harbors disclosed a new 10-year disposal contract, covering incineration waste and complex wastewater volumes, with a manufacturer expanding its US operations.
The company estimates the contract’s value at $600 million over its term, with options to expand in scope. It’s set to begin in the fourth quarter and reach full capacity in 2030 as the customer ramps up multiple manufacturing sites.
“This customer selected Clean Harbors as a long-term partner because of the vast capabilities, scale and redundancy of our disposal network,” Gerstenberg said, adding that the deal reflects broader US reshoring trends.
Separately, Clean Harbors signed a definitive agreement to acquire ES&H, a Gulf Coast environmental and emergency response provider, for $305 million in cash.
The Louisiana-based company operates 13 service branches, most in coastal locations supporting maritime response work, and holds the Coast Guard’s highest Oil Spill Response Organization classification. This is the same designation Clean Harbors holds.
ES&H generates about $90 million in annual base revenue and $30 million in adjusted EBITDA, according to the company.
Battles said ES&H “has built an outstanding reputation with its customers over a 30-year history.”
Clean Harbors expects roughly $5 million in cost synergies after the acquisition’s first full year. The deal is expected to close in the second half of 2026, pending regulatory approval, according to the company.
Outlook
Gerstenberg cited a US Manufacturing PMI that stayed above 50, signaling expansion, through the first six months of 2026, along with a growing PFAS pipeline in the US and Canada spanning private and government customers.
Clean Harbors’ PFAS-related business spans treatment and remediation, incineration-based destruction, and filtration projects for both government and private customers.
Gerstenberg said the company’s PFAS growth has accelerated to more than 30% year over year, up from an earlier 20% pace, aided in part by the Department of Defense lifting its moratorium on incineration.
He noted that Industrial Services is introducing a new offering targeting data centers that’s expected to support growth in the years ahead, while multiple large emergency response events already underway should support third-quarter growth in Field Services.
On data centers specifically, Gerstenberg said the company has “already won work on 10 sites” and is bidding on a dozen more.
Clean Harbors expects third-quarter adjusted EBITDA to grow 24% to 28% year over year. The company raised the midpoint of its full-year adjusted EBITDA guidance by $110 million and its adjusted free cash flow guidance midpoint by $30 million.
For the full year, Clean Harbors now expects adjusted EBITDA of $1.35 billion to $1.41 billion, up from prior guidance of $1.24 billion to $1.30 billion, and adjusted free cash flow of $520 million to $580 million, up from $490 million to $550 million, based on anticipated net cash from operating activities of $890 million to $1.01 billion.
Q2 2026 highlights:
- Revenue: $1.74 billion, up 12% year over year, from $1.55 billion Q2 2025
- Net income: $170.5 million, up 34%, from $126.9 million Q2 2025
- Adjusted EBITDA: $409.0 million, up 22%, from $336.2 million Q2 2025
- Adjusted EBITDA margin: 23.6%, up 190 basis points, from 21.7% Q2 2025
- Adjusted free cash flow: $135.7 million, up 2%, from $133.2 million Q2 2025
- Environmental Services adjusted EBITDA: $406.1 million, up 8%, from $376.2 million Q2 2025
- SKSS adjusted EBITDA: $93.0 million, up 143%, from $38.3 million Q2 2025
