M&A activity snapshot
Environmental consulting is in the middle of its largest consolidation wave. Environmental Business Journal counts 80 U.S. firms with more than $100 million in environmental revenue, holding 76% of the market in 2024. EBJ says global strategics and PE platforms are buying capabilities in PFAS, resilience, energy transition, data centers and permitting.
The market itself is large and still growing. EBJ sizes U.S. environmental consulting and engineering at $49 billion in 2024, with growth moderating to 6-7% in 2025 and 6-8% in 2026. That is a step down from the double-digit years funded by infrastructure money, PFAS and ESG work.
Deal volume is recovering after a soft 2025. Capstone Partners counted 61 environmental, health and safety (EHS) transactions in the first half of 2026, up 15.1%, after full-year 2025 volume hit a five-year low. Capstone's EHS category is broader than consulting alone, so treat it as a proxy for this vertical.
This page covers environmental consulting (NAICS 541620), Phase I and II site assessment, compliance and permitting, and remediation services. Civil design, geotechnical testing and surveying are covered on their own pages.
Who is buying
PE-backed environmental platforms. Sponsors made 71 deals and a record 48.3% of EHS M&A in 2025. Verdantas is a typical example: when Sterling Investment Partners bought it in 2024, it had acquired 18 companies since 2020 and employed over 1,450 staff. Its add-ons include Project Navigator, a CERCLA and state Superfund site coordination specialist.
New platform investments. Large platforms are trading between sponsors. Ridgemont Equity Partners bought ENTACT, a remediation and geotechnical contractor with 18 offices and approximately 900 associates, in August 2026. Veritas Capital agreed to buy Trinity Consultants from Oak Hill, which will reinvest and remain a minority shareholder.
Small-firm add-ons. Platforms also buy very small compliance shops. ALL4, owned by Levine Leichtman, acquired Tora Consulting, an air permitting firm with 15 experienced environmental professionals.
Public environmental and industrial services companies. Montrose Environmental Group changed its name to Onterris on April 17, 2026. Its 10-K cites over 70 acquisitions since its inception in 2012. It made no acquisitions in 2025 or the first half of 2026. In August 2026 its board opened a strategic review that includes evaluating acquisition interest in the company. Clean Harbors bought remediation and emergency response provider HEPACO from Gryphon Investors for $400 million in cash.
Global engineering strategics. Montrose's 10-K names the environmental arms of ERM, Ramboll, Geosyntec, WSP, Tetra Tech and AECOM among its competitors. These firms buy specialists to add technical depth or regional reach.
What buyers look for
Recurring, regulation-driven revenue. Buyers prize compliance, testing and monitoring because it repeats. Montrose reported that clients generating approximately 96% of 2024 revenue repeated in 2025. By contrast, its remediation segment, 33.4% of 2025 revenue, earns mostly through project-based, fixed-price work.
PFAS capability with staying power. EBJ says PFAS work is shifting from emergency sampling into multi-year treatment design and utility capex. The federal rules are mixed. EPA has proposed rescinding limits for PFHxS, PFNA, GenX and a PFBS hazard-index mixture. Yet PFOA and PFOS limits stay at 4.0 ppt, with an optional extension to 2031.
CERCLA liability work. EPA chose to retain the CERCLA hazardous substance designation for PFOA and PFOS in September 2025. The D.C. Circuit then denied industry petitions against it on August 18, 2026. That keeps PFAS inside Superfund cost recovery, investigation and remediation for years.
Transaction-driven site assessment. Phase I work is anchored in federal rules. EPA's All Appropriate Inquiries rule recognizes ASTM E1527-21 as a way to qualify for CERCLA liability protection, such as bona fide prospective purchaser status. Phase I volume follows real estate and lending activity, so buyers look past one strong year.
What makes a strong company
An environmental firm that draws premium interest typically has:
- A majority of revenue from recurring compliance, permitting, monitoring or multi-year programs, not one-off projects.
- Documented PFAS experience (sampling, treatment design, litigation support) tied to clients with ongoing obligations.
- Credentialed technical staff who sign reports, such as Phase I environmental professionals and licensed engineers or geologists, committed beyond closing.
- A client mix across industrial, utility, federal and state customers, with no single program dominating.
- Clean insurance and claims history, since remediation and assessment errors create long-tail liability.
- Lab accreditations, permits and contract vehicles that transfer to a new owner.
Valuation and deal structure
Most small and mid-sized firms trade in mid-single-digit EBITDA multiples. Rusk O'Brien Gido's 2025 study of engineering, architecture and environmental consulting deals shows a median of 5.30 and an upper quartile of 6.77 EV/EBITDA. That sample mixes engineering and architecture firms, so it is a proxy, not an environmental-only figure.
Larger deals clear higher. HEPACO brought $400 million on about $36 million of 2023 adjusted EBITDA, roughly 11.1x before cost savings (Axia arithmetic). Clean Harbors presented it as 7.1 times after an expected $20 million in cost savings. Most platform deals, including ENTACT and Trinity, do not disclose terms.
Earnouts and rollover are standard. Montrose paid $17.8 million of contingent consideration in 2025, part of it in stock. It disclosed up to $17.6 million in further earn-out payments in 2026 and 2027. In sponsor deals, sellers often roll equity, as Verdantas management and employees did in retaining significant equity. To see where your own numbers sit, use the valuation tool.
Outlook
Expect sponsor-led consolidation to continue through 2027, with buyers paying most for recurring compliance and PFAS program work. Federal funding is mixed. EPA announced $248 million in Brownfields Multipurpose, Assessment, and Cleanup grants to 190 communities in June 2026. FY2026 Superfund appropriations fell to $282.8 million, 47.4% below FY2025.
EPA plans to use a projected $1.60 billion from Superfund tax receipts for remedial and emergency response work, and IIJA advance appropriations end after FY2026. Project-heavy firms also face volatility: Onterris cut 2026 adjusted EBITDA guidance to $117.0 million to $120.0 million on lower emergency response revenue. Owners with recurring, regulation-driven revenue are best placed for a sale in the next 12-24 months.
Own an environmental consulting or remediation firm and want a sense of its value before you talk to anyone? Run the valuation tool. See also: how buyers build an M&A target list and the Engineering & Environmental Services M&A overview.