Company lists · Data refreshed September 2026

Top 25 Offshore environmental consulting based in the United States

Name: Offshore environmental consulting based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 20, 2026 2,465 companies tracked

RevenueBase identified 2,465 offshore environmental consulting headquartered in the United States as of September 2026 and tracks 47,402 professional contacts across them, including 21,337 with verified work emails. Houston is the largest hub.

This list covers offshore environmental consulting headquartered in the United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 20, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 20, 2026 86% judged on-target in blind review

2,465Companies

47,402Contacts tracked

21,337Verified emails

Explore this list → Free signup · no credit card · 500 free credits

The 25 largest offshore environmental consulting based in the United States

Ranked by team size

Top 25 of 2,465 offshore environmental consulting based in the United States, ranked by team size, largest first. Data refreshed Sep 20, 2026. RevenueBase Smart Search rates how each company's information relates to offshore environmental consulting: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Swca Environmental Consultants	Strong evidence	Phoenix, AZ, United StatesHQ checked Sep 20, 2026	1,001-5,000	1,629 contacts →
	Strong evidence “Founded on a commitment to sound science and creative solutions, SWCA is a leader in environmental and management consulting services.” Source: RevenueBase Database · checked Sep 20, 2026
2	Montrose Environmental Group	Partial evidence	Little Rock, AR, United StatesHQ checked Sep 20, 2026	1,001-5,000	1,529 contacts →
	Partial evidence “Onterris (formerly Montrose Environmental Group) was one of the first to see environmental responsibility as not just an imperative but as a strategic asset.” Source: RevenueBase Database · checked Sep 20, 2026
3	Apex Companies	Indirect evidence	Rockville, MD, United StatesHQ checked Sep 20, 2026	1,001-5,000	1,137 contacts →
	Indirect evidence “Who is Apex?” Source: RevenueBase Database · checked Sep 20, 2026
4	Barr Engineering CO	Strong evidence	Minneapolis, MN, United StatesHQ checked Sep 20, 2026	1,001-5,000	1,088 contacts →
	Strong evidence “Barr provides engineering and environmental consulting services to clients across the Midwest, throughout the Americas, and around the world.” Source: RevenueBase Database · checked Sep 20, 2026
5	Trinity Consultants	Partial evidence	Dallas, TX, United StatesHQ checked Sep 20, 2026	1,001-5,000	961 contacts →
	Partial evidence “Trinity Consultants is a global team of experts helping organizations solve complex challenges in environmental compliance, ecological protection, infrastructure performance, and…” Source: RevenueBase Database · checked Sep 20, 2026
6	ATC Group Services LLC	Indirect evidence	Lafayette, LA, United StatesHQ checked Sep 20, 2026	1,001-5,000	865 contacts →
	Indirect evidence “ATC Group Services LLC is now Atlas.” Source: RevenueBase Database · checked Sep 20, 2026
7	Environmental Science Associates	Strong evidence	San Francisco, CA, United StatesHQ checked Sep 20, 2026	501-1,000	732 contacts →
	Strong evidence “ESA is a 100% employee-owned environmental consulting firm.” Source: RevenueBase Database · checked Sep 20, 2026
8	Antea Group USA	Strong evidence	St Paul, MN, United StatesHQ checked Sep 20, 2026	1,001-5,000	658 contacts →
	Strong evidence “Antea Group is an international engineering and environmental consulting firm specializing in full-service solutions in the fields of environment, health and safety, and…” Source: RevenueBase Database · checked Sep 20, 2026
9	EBI Consulting	Indirect evidence	Burlington, MA, United StatesHQ checked Sep 20, 2026	501-1,000	535 contacts →
	Indirect evidence “For 35 years we have been helping investors, lenders, owners, developers, contractors, and property managers reduce risk and optimize their built facilities, infrastructure and…” Source: RevenueBase Database · checked Sep 20, 2026
10	Nova Engineering And Environmental, LLC	Strong evidence	Kennesaw, GA, United StatesHQ checked Sep 20, 2026	501-1,000	518 contacts →
	Strong evidence “Established in 1996, NOVA was originally founded to provide Environmental Consulting, Geotechnical Engineering, and Construction Materials Testing and Inspection services to the…” Source: RevenueBase Database · checked Sep 20, 2026
11	Anchor QEA	Strong evidence	Seattle, WA, United StatesHQ checked Sep 20, 2026	501-1,000	479 contacts →
	Strong evidence “Headquartered in Seattle, Washington, Anchor QEA is a nationally recognized environmental science and engineering consulting firm specializing in aquatic, shoreline, and water…” Source: RevenueBase Database · checked Sep 20, 2026
12	Rincon Consultants	Strong evidence	Ventura, CA, United StatesHQ checked Sep 20, 2026	501-1,000	479 contacts →
	Strong evidence “Rincon Consultants is a multi-disciplinary environmental sciences, planning, and engineering consulting firm that provides quality professional services to government and industry.” Source: RevenueBase Database · checked Sep 20, 2026
13	Groundwater & Environmental Services, INC	Partial evidence	Wall Township, NJ, United StatesHQ checked Sep 20, 2026	201-500	447 contacts →
	Partial evidence “We are Groundwater & Environmental Services, Inc, better known as GES.” Source: RevenueBase Database · checked Sep 20, 2026
14	ROUX	Strong evidence	Islandia, NY, United StatesHQ checked Sep 20, 2026	201-500	433 contacts →
	Strong evidence “Founded 40 years ago, Roux is recognized for being a highly effective, client-focused environmental consulting and management firm.” Source: RevenueBase Database · checked Sep 20, 2026
15	Western Ecosystems Technology, Inc. West	Strong evidence	Cheyenne, WY, United StatesHQ checked Sep 20, 2026	201-500	408 contacts →
	Strong evidence “WEST provides environmental and statistical consulting services and contract research nationally and internationally to industry, government, and private organizations.” Source: RevenueBase Database · checked Sep 20, 2026
16	CME Associates	Partial evidence	Parlin, NJ, United StatesHQ checked Sep 20, 2026	201-500	336 contacts →
	Partial evidence “CME Associates, with eight (8) office locations throughout New Jersey, provides a complete range of Environmental, Geotechnical, Engineering, Surveying and Planning services.” Source: RevenueBase Database · checked Sep 20, 2026
17	Environmental Consulting & Technology, Inc. ECT	Strong evidence	Gainesville, FL, United StatesHQ checked Sep 20, 2026	201-500	305 contacts →
	Strong evidence “Environmental Consulting & Technology, Inc.(ECT) is a multi-disciplinary environmental and sustainability consulting firm delivering strategy, permitting, design, and management…” Source: RevenueBase Database · checked Sep 20, 2026
18	Ecology And Environment, INC	Indirect evidence	Lancaster, NY, United StatesHQ checked Sep 20, 2026	5,001-10,000	278 contacts →
	Indirect evidence “E&E is now WSP USA.” Source: RevenueBase Database · checked Sep 20, 2026
19	Crosby Energy Services	Indirect evidence	Cut Off, LA, United StatesHQ checked Sep 20, 2026	201-500	272 contacts →
	Indirect evidence “Founded as C&D Wireline in 1968, with C&D Production Specialist joining the business in 1993, today Crosby Energy Services is a certified Women’s Business Enterprise National…” Source: RevenueBase Database · checked Sep 20, 2026
20	Intera Incorporated	Strong evidence	Austin, TX, United StatesHQ checked Sep 20, 2026	201-500	259 contacts →
	Strong evidence “Established in 1974, INTERA is a geosciences and engineering consulting firm focused on providing water resources and supply, environmental, mining, radioactive waste isolation…” Source: RevenueBase Database · checked Sep 20, 2026
21	GSI Environmental INC	Strong evidence	Houston, TX, United StatesHQ checked Sep 20, 2026	201-500	259 contacts →
	Strong evidence “GSI Environmental, Inc.(GSI), is an environmental engineering and science consulting firm committed to measuring, analyzing, and solving complex environmental problems around the…” Source: RevenueBase Database · checked Sep 20, 2026
22	Environmental Works, INC	Partial evidence	Springfield, MO, United StatesHQ checked Sep 20, 2026	201-500	238 contacts →
	Partial evidence “Environmental Works, Inc.(EWI) offers truly comprehensive environmental solutions for a variety of industries, businesses, and municipalities.” Source: RevenueBase Database · checked Sep 20, 2026
23	Metiri Group	Partial evidence	Clovis, CA, United StatesHQ checked Sep 20, 2026	n/a	233 contacts →
	Partial evidence “Appl Inc is an environmental services company based out of 908 N Temperance Ave, Clovis, CA, United States.” Source: RevenueBase Database · checked Sep 20, 2026
24	Seatrium Amfels, INC	Partial evidence	Brownsville, TX, United StatesHQ checked Sep 20, 2026	1,001-5,000	229 contacts →
	Partial evidence “Seatrium AmFELS is an industry pioneer committed to sustainability by providing cleaner offshore & marine solutions, offshore renewables, and new energy, generating long-term…” Source: RevenueBase Database · checked Sep 20, 2026
25	Kleinschmidt Associates	Partial evidence	Pittsfield, ME, United StatesHQ checked Sep 20, 2026	201-500	218 contacts →
	Partial evidence “At Kleinschmidt, we work primarily with energy companies and government agencies in North America to protect and enhance the environment without compromising performance.” Source: RevenueBase Database · checked Sep 20, 2026

RevenueBase Smart Search

RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: offshore environmental consulting. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.

Strong evidence: The company's own public description of its business names offshore environmental consulting.
Partial evidence: Its own public description names part of offshore environmental consulting, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name offshore environmental consulting. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.

RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.

Showing 25 of 2,465 offshore environmental consulting based in the United States

See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 21,337 reachable decision-makers.

Free signup · no credit card

View the full list →

Offshore environmental consulting based in the United States at a glance

As of Sep 20, 2026

45.0%Verified-email coverage

19.2Average contacts per company

1-10Median size (employees)

6.2%Largest-city concentration · Houston

Sep 20, 2026Page data refreshed

Companies by employee count

1-10

1,329

11-50

838

51-200

216

201-500

501-1,000

1,001-5,000

5,001-10,000

10001+

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 2,465 companies.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among offshore environmental consulting, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies: Companies headquartered in the United States whose own description of what they do matches “offshore environmental consulting”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search: RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names offshore environmental consulting), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude: Companies whose own description does not clearly place them among offshore environmental consulting, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
Match quality: In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
Ranking: Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification: Every listed company carries at least one verified work email, 21,337 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh: This page's figures were pulled from the company graph on September 20, 2026. Lists refresh periodically as the graph is re-checked.
Corrections: Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Offshore environmental consulting by metro

Offshore environmental consulting in Houston153
Offshore environmental consulting in Seattle38

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names offshore environmental consulting, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many offshore environmental consulting are there based in the United States?

RevenueBase identified 2,465 offshore environmental consulting headquartered in the United States as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Swca Environmental Consultants, headquartered in Phoenix, tops this list with the largest team on record.

Which city has the most offshore environmental consulting?

Houston leads with 153 headquartered companies, followed by Seattle (38) and Austin (22).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 21,337 verified decision-maker contacts tracked across these 2,465 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 20, 2026.

Ready to reach these companies? Verified emails and direct dials for all 2,465 offshore environmental consulting based in the United States. Start with a free account, no credit card.

Download this list →

Related lists

Offshore environmental consulting by geography

Browse the directory

About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.