Remediation Services (U.S.) — NAICS 56291

A short investor's primer on the industry group that cleans up contaminated soil, groundwater, and buildings — relevant to both public-market and private investors.

("NAICS" is the North American Industry Classification System, the U.S. government's standard code set for industries. A five-digit code like 56291 is a "NAICS industry"; the six-digit codes beneath it are "national industries.")

1. Overview

Remediation is the business of making contaminated land, water, and structures safe again: pumping and treating polluted groundwater, digging out and hauling off tainted soil, stripping asbestos and lead paint from old buildings, reclaiming former mines, and decommissioning industrial and nuclear sites. It is a "someone has to pay to fix this" industry — most work is driven by law, liability, or a property transaction, not by a customer who wants a nicer product [3].

This page covers NAICS 56291, the five-digit industry level. It exists mainly as a bookkeeping tier in the classification tree — everything meaningful about it lives one level down, in its single child.

2. What's inside — and why this level equals its one child

NAICS 56291 contains exactly one six-digit national industry:

Because there is only one child, 56291 and 562910 are the same industry — identical scope, identical firms, identical statistics. The five-digit tier adds no separate activity; it is a single-child pass-through.

So this page is deliberately short. For the full treatment — what the work is, the value-chain split across other codes, the company-by-company investable universe, deal history, and the PFAS ("forever chemicals," per- and polyfluoroalkyl substances) growth story — read the 562910 leaf primer. Everything below is a condensed rollup; 562910 is the source of record.

3. Size (this level's rollup figures)

Because 56291 equals 562910, the rollup figures for this level are the child's figures — there is nothing else to add up.

Ground-truth federal figures (from our ingested stats for 56291). Employment and payroll are from the Census Bureau's County Business Patterns (CBP) for 2023; receipts, firms, and concentration are from the 2022 Economic Census.

Fragmentation. The industry is extraordinarily fragmented: the top four firms hold just 9.0% of revenue, the top eight 14.3%, the top 20 25.1%, and the top 50 only 37.4% [2]. The Herfindahl-Hirschman Index (HHI, a standard concentration measure running up to 10,000) is 43.2 [2] — one of the lowest readings in any U.S. industry, meaning no player has anything like pricing power over the whole market.

Undercount caveat — important here. The Census $22.74 billion understates how much is actually spent cleaning up contamination in America, and the reasons matter because most of the industry is small and privately held:

1. CBP counts only employer establishments — it excludes non-employer (self-employed) operators and most government crews, so the smallest firms fall outside the count [5].
2. Government does much of the work directly. The U.S. Department of Energy's (DOE) Environmental Management program — the world's largest environmental cleanup effort — runs roughly $8 billion a year on its own, but that flows through federal and professional-services codes, not "Remediation Services" [11].
3. Big diversified firms bury it elsewhere. Waste, engineering, oil, and chemical companies that perform remediation often book it under waste management, engineering, or the parent industry.
4. It excludes the design and dig portions of every project (environmental consulting and site preparation sit under other codes).

The federal data also publish no industry-wide profit margin, backlog, capacity-utilization, or public-vs-private ownership split. Treat $22.74 billion as the size of the stand-alone private remediation-contracting industry, and understand that total U.S. remediation activity — federal, in-house, and contracted — is materially larger.

4. Investable universe (where value concentrates)

Since 56291 is a single-child level, value concentrates exactly where it does in 562910: there is no large listed pure-play and no dedicated exchange-traded fund (ETF). Public exposure is a build-your-own basket of a few focused operators plus diversified firms with remediation arms; the more direct routes are private. Do not assign any company NAICS 56291 market share from its consolidated revenue — each reports substantial adjacent activity.

The most focused listed names are Clean Harbors (CLH; scale plus owned hazardous-waste disposal), Tetra Tech (TTEK; government-heavy environmental engineering), Onterris (ONT; the smaller ex-Montrose Environmental vehicle), and Perma-Fix (PESI; a micro-cap nuclear-waste and PFAS-destruction bet). Diversified exposure runs through the waste majors Republic Services (RSG) and Waste Management (WM) and the federal/nuclear engineers AECOM (ACM), Jacobs (J), Amentum (AMTM), and Fluor (FLR). Most of the actual industry, though, is the ~5,100 private regional contractors, employee-owned specialists, and private-equity-backed platforms. See the 562910 primer for the full table, tickers, scale figures, and private owners [2][15][16].

5. How the money works

Economics look like engineering and field services, not a product company, and are identical to 562910:

• Backlog and book-to-bill drive revenue visibility; a book-to-bill above 1.0 means the pipeline refills faster than work burns off.
• Contract type sets the risk — time-and-materials (lowest risk when contamination is uncertain), cost-plus (common on big federal jobs), or fixed-price (contractor eats overruns). Federal nuclear cleanup has a long, Government Accountability Office (GAO)-documented history of cost and schedule overruns.
• Vertical integration into disposal — owning incinerators or hazardous landfills (as Clean Harbors and Republic/US Ecology do) captures treatment and tipping-fee margin on top of field work, the main edge the big players hold over pure contractors.
• Recurring vs. event-driven — long-term groundwater monitoring and multi-year consent-decree cleanups produce annuity-like revenue, prized because it is sticky and non-discretionary; emergency spills and demolitions are one-off.

There is no industry-wide margin or utilization figure — use company disclosures. Full detail is in the 562910 primer.

6. Demand drivers

The same forces that drive 562910 drive this level:

• Regulation and liability — the base driver; CERCLA ("Superfund"), RCRA, and state programs make cleanup non-optional, and enforcement intensity moves demand directly.
• Emerging contaminants, above all PFAS — the biggest secular tailwind. The Environmental Protection Agency (EPA) designated PFOA and PFOS as CERCLA hazardous substances in 2024 and retained it in 2025 [9], turning thousands of sites into cleanup candidates; third-party forecasters put the PFAS-remediation niche at roughly $1.2 billion in 2025 rising toward ~$2 billion by 2030 [14].
• Federal funding — the 2021 Infrastructure Investment and Jobs Act put $3.5 billion into Superfund and $1.5 billion-plus into Brownfields [10]; DOE's ~$8-billion-a-year cleanup program funds the nuclear end [11].
• Real-estate redevelopment (brownfields), industrial and energy activity, emergency response, and nuclear decommissioning round out the demand base.

7. Regulation

Remediation is downstream of environmental law — the statutes essentially create the industry. The key regimes are CERCLA/Superfund (strict, retroactive, joint-and-several liability on potentially responsible parties) [6], RCRA (cradle-to-grave hazardous-waste rules) [7], the federal Brownfields grant program, TSCA (asbestos, lead, PCBs), and OSHA HAZWOPER (the Hazardous Waste Operations and Emergency Response safety standard, a compliance cost and barrier to entry) [8]. Regulation cuts both ways for investors: tighter rules and new contaminant listings (PFAS) expand the market, while deregulation or slower enforcement shrinks mandated spending — and the PFAS designation itself faces ongoing litigation. Full detail is in 562910.

8. Consolidation

The defining feature is fragmentation (top-four share of 9%, HHI of 43 [2]), which is exactly what attracts financial buyers. Private equity is rolling up the long tail, forming platforms and bolting on specialists in PFAS treatment, wastewater, and brownfields [18]. Strategics are integrating vertically — recent deals include Republic Services' $2.2 billion purchase of US Ecology (2022), Clean Harbors' ~$400 million HEPACO acquisition (2024), and Veolia's ~$3 billion Clean Earth completion (2026) [15][16][17]. Federal cleanup is oligopolistic at the top, with multi-billion-dollar DOE contracts won by joint ventures of a few large firms [12]. Likely trajectory: a slowly consolidating middle, with a large tail of small local operators persisting because much of the work is inherently local.

9. Risks

Identical to 562910: government-funding and political risk (demand leans on federal appropriations and enforcement posture); regulatory two-sidedness (new listings grow the market, deregulation shrinks it — and the PFAS rule is in litigation); fixed-price execution risk (contamination is often less understood than the bid assumes); safety and incident risk (handling hazardous and radioactive material); labor risk (scarce licensed, safety-certified crews); disposal-capacity risk; cyclicality in event- and redevelopment-linked work; client/contract concentration for federal-heavy contractors; acquisition and integration risk in roll-ups; working-capital drag from slow-paying clients; and disclosure risk — private operators disclose little and public parents give only limited segment detail, so pure-industry visibility is poor.

10. How to invest and the outlook

Because 56291 equals 562910, so does the playbook. Public routes are a build-your-own basket where the quality of exposure matters more than the label — Clean Harbors and Tetra Tech for the most focused liquid exposure, Onterris and Perma-Fix as smaller/faster-growing bets, and the waste majors and federal engineers for diversified exposure. Private routes are the more direct way into the pure industry, since ~5,100 of the firms are private [2]: backing a PE roll-up platform, directly owning a regional contractor, or a specialist PFAS-treatment play.

Base case: a low-to-mid-single-digit-growth core industry with a genuine higher-growth option embedded in PFAS and emerging contaminants — steady, regulation-anchored demand; a heavily private and consolidating supplier base; and a small, indirect public opportunity set. For the full company table, diligence checklist, and near-term watch items, see the 562910 primer — this five-digit level adds nothing beyond it.

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Sources

This is a rollup page; sources are drawn from the 562910 child primer and our ground-truth federal stats for 56291.

1. U.S. Census Bureau, County Business Patterns (2023), NAICS 562910 — establishments (5,826), employment (91,239), annual payroll ($7.057B), Q1 payroll ($1.670B). https://www.census.gov/programs-surveys/cbp.html
2. U.S. Census Bureau, 2022 Economic Census — receipts and concentration, NAICS 562910 — receipts ($22.739B), firms (5,115), CR4 9.0% / CR8 14.3% / CR20 25.1% / CR50 37.4%, HHI 43.2. https://www.census.gov/programs-surveys/economic-census.html
3. U.S. Census Bureau / NAICS, 2022 NAICS 562910 Remediation Services — definition and cross-references. https://www.census.gov/naics/?details=562910&year=2022
4. U.S. Census Bureau, County Business Patterns — About / coverage (employer establishments only; excludes non-employers and most government). https://www.census.gov/programs-surveys/cbp/about.html
5. Congressional Research Service / U.S. EPA, CERCLA ("Superfund") overview and liability. https://www.epa.gov/superfund/superfund-cercla-overview
6. U.S. EPA, Resource Conservation and Recovery Act (RCRA) Overview. https://www.epa.gov/rcra/resource-conservation-and-recovery-act-rcra-overview
7. Occupational Safety and Health Administration, HAZWOPER standards (29 CFR 1910.120). https://www.osha.gov/emergency-preparedness/hazardous-waste-operations/standards
8. U.S. EPA, PFOA and PFOS designated CERCLA hazardous substances (April 2024) and Brownfields FAQs / 2025 retention. https://www.epa.gov/brownfields/faqs-what-epas-designation-pfoa-and-pfos-cercla-hazardous-substances-means-epas
9. U.S. EPA, Infrastructure Investment and Jobs Act — $3.5B Superfund remedial and ~$1.5B Brownfields; Superfund excise tax reinstated (2022–2031). https://www.epa.gov/infrastructure/cleaning-superfund-sites-highlights-infrastructure-investment-and-jobs-act-funding
10. U.S. Department of Energy, FY 2025 Budget in Brief — Environmental Management (~$8B, "largest environmental cleanup program"). https://www.energy.gov/sites/default/files/2024-03/doe-fy-2025-budget-in-brief.pdf
11. ANS Nuclear Newswire / Nuclear Engineering International, DOE Hanford tank-waste (~$45B) and Central Plateau cleanup contract awards. https://www.ans.org/news/article-5832/doe-again-awards-45-billion-hanford-tank-contract-to-h2c/
12. Virtue Market Research / Exactitude Consultancy, PFAS Remediation Market — ~$1.2B (2025) to ~$2B (2030), ~10–13% CAGR (private forecast). https://virtuemarketresearch.com/report/pfas-remediation-market
13. Clean Harbors, Inc., Third-Quarter 2025 Financial Results and 2025 Form 10-K. https://ir.cleanharbors.com/news-releases/news-release-details/clean-harbors-announces-third-quarter-2025-financial-results
14. Tetra Tech, Inc., Fourth Quarter and Fiscal 2025 Results — revenue $5.44B. https://investor.tetratech.com/news/news-details/2025/Tetra-Tech-Reports-Strong-Fourth-Quarter-and-Fiscal-2025-Results/default.aspx
15. Republic Services / Waste Dive — US Ecology acquisition ($2.2B, 2022); Environmental Solutions segment and 2025 volume softness. https://www.wastedive.com/news/republic-services-us-ecology-environmental-solutions/618561/
16. Clean Harbors, Clean Harbors Completes ~$400M Acquisition of HEPACO (2024). https://www.cleanharbors.com/2024/clean-harbors-completes-acquisition-of-hepaco
17. Veolia, Veolia Completes Clean Earth Deal (~$3B, June 2026), Doubling Its U.S. Hazardous-Waste Business. https://www.veolia.com/en/our-media/press-releases/veolia-completes-clean-earth-deal-doubling-its-us-hazardous-waste-business
18. Capstone Partners, Industrial & Environmental Services M&A Update — PE roll-ups in PFAS, wastewater, brownfields, 2025. https://www.capstonepartners.com/insights/article-industrial-environmental-services-market-update/