Company lists · Data refreshed October 2026

Top 25 Environmental consulting companies for oil and gas based in the United States

Name: Environmental consulting companies for oil and gas based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Oct 12, 2026 4,757 companies tracked

RevenueBase identified 4,757 company matches for environmental consulting companies for oil and gas associated with the United States as of October 2026 and tracks 110,678 professional contacts across them, including 43,493 with verified work emails. Houston is the largest hub.

This list covers company matches for environmental consulting companies for oil and gas associated with the United States, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed October 12, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, 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 RevenueBase SmartSearch · Exact Recorded Oct 12, 2026 How this list was built

4,757Companies

110,678Contacts tracked

43,493Verified emails

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

The 25 largest environmental consulting companies for oil and gas based in the United States

Ranked by team size

Top 25 of 4,757 company matches for environmental consulting companies for oil and gas based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Oct 12, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#	Company	RevenueBase SmartSearch	Headquarters	Employees	Contacts
1	Langan Engineering & Environmental Services	Exact match	Parsippany, NJ, United StatesHQ recorded Oct 12, 2026	1,001-5,000	2,402 contacts →
	Exact match “Langan's client-focused, highly entrepreneurial culture cultivates an environment of opportunities in which career growth and teamwork flourish.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
2	Hazen And Sawyer	Exact match	New York, NY, United StatesHQ recorded Oct 12, 2026	1,001-5,000	2,251 contacts →
	Exact match “As Hazen marks 75 years, we celebrate a legacy of absolute commitment to our clients while delivering the best technical work available anywhere.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
3	Civil & Environmental Consultants, INC	Exact match	Moon Township, PA, United StatesHQ recorded Oct 12, 2026	1,001-5,000	2,204 contacts →
	Exact match “Civil & Environmental Consultants, Inc.(CEC) provides comprehensive market-oriented consulting services that advance the strategic business objectives of its clients.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
4	Swca Environmental Consultants	Exact match	Phoenix, AZ, United StatesHQ recorded Oct 12, 2026	1,001-5,000	1,661 contacts →
	Exact match “Founded on a commitment to sound science and creative solutions, SWCA is a leader in environmental and management consulting services.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
5	Atwell, LLC	Exact match	Southfield, MI, United StatesHQ recorded Oct 12, 2026	1,001-5,000	1,499 contacts →
	Exact match “Atwell is a full-service consulting, engineering and construction services firm that delivers a broad range of creative solutions to clients in the real estate and land…” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
6	Partner Engineering & Science, INC	Exact match	Torrance, CA, United StatesHQ recorded Oct 12, 2026	1,001-5,000	1,418 contacts →
	Exact match “Partner Assessment Corp.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
7	PMI	Exact match	Irvine, CA, United StatesHQ recorded Oct 12, 2026	n/a	1,361 contacts →
	Exact match “Training and Development Solutions” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
8	Knight Piesold	Exact match	Denver, CO, United StatesHQ recorded Oct 12, 2026	1,001-5,000	1,326 contacts →
	Exact match “Knight Piésold is an employee-owned, global consulting firm providing specialist services to the mining, power, water resources, and infrastructure industries.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
9	Apex Companies	Exact match	Rockville, MD, United StatesHQ recorded Oct 12, 2026	1,001-5,000	1,266 contacts →
	Exact match “Who is Apex?” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
10	Barr Engineering CO	Exact match	Minneapolis, MN, United StatesHQ recorded Oct 12, 2026	1,001-5,000	1,108 contacts →
	Exact match “Barr provides engineering and environmental consulting services to clients across the Midwest, throughout the Americas, and around the world.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
11	Trinity Consultants	Exact match	Dallas, TX, United StatesHQ recorded Oct 12, 2026	1,001-5,000	1,077 contacts →
	Exact match “Trinity Consultants is a global team of experts helping organizations solve complex challenges in environmental compliance, ecological protection, infrastructure performance, and…” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
12	Alliance Technical Group	Exact match	Decatur, AL, United StatesHQ recorded Oct 12, 2026	1,001-5,000	1,048 contacts →
	Exact match “Alliance is a new kind of environmental services company-powered by innovation, focused on service, and committed to client success.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
13	ATC Group Services LLC	Exact match	Lafayette, LA, United StatesHQ recorded Oct 12, 2026	1,001-5,000	872 contacts →
	Exact match “ATC Group Services LLC is now Atlas.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
14	Montrose Environmental Group	Exact match	Little Rock, AR, United StatesHQ recorded Oct 12, 2026	1,001-5,000	843 contacts →
	Exact match “Onterris (formerly Montrose Environmental Group) was one of the first to see environmental responsibility as not just an imperative but as a strategic asset.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
15	Pioneer Energy Services	Exact match	San Antonio, TX, United StatesHQ recorded Oct 12, 2026	1,001-5,000	814 contacts →
	Exact match “Pioneer Energy Services is now Patterson-UTI” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
16	The Foth Companies	Exact match	De Pere, WI, United StatesHQ recorded Oct 12, 2026	501-1,000	812 contacts →
	Exact match “By combining science, engineering, and technology with a true collaborative spirit, Foth has delivered innovative solutions to our clients since 1938.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
17	DUDEK	Exact match	Encinitas, CA, United StatesHQ recorded Oct 12, 2026	501-1,000	807 contacts →
	Exact match “Dudek is an environmental, planning, and engineering consulting firm.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
18	EDG	Exact match	Metairie, LA, United StatesHQ recorded Oct 12, 2026	501-1,000	736 contacts →
	Exact match “EDG Inc.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
19	Environmental Science Associates	Exact match	San Francisco, CA, United StatesHQ recorded Oct 12, 2026	501-1,000	730 contacts →
	Exact match “ESA is a 100% employee-owned environmental consulting firm.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
20	Antea Group USA	Exact match	St. Paul, MN, United StatesHQ recorded Oct 12, 2026	1,001-5,000	658 contacts →
	Exact match “Antea Group is an international engineering and environmental consulting firm specializing in full-service solutions in the fields of environment, health and safety, and…” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
21	Fesco, LTD	Exact match	Alice, TX, United StatesHQ recorded Oct 12, 2026	1,001-5,000	652 contacts →
	Exact match “FESCO is a diversified energy services company providing quality equipment and experienced personnel since 1949.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
22	Consultec International INC	Exact match	Miami, FL, United StatesHQ recorded Oct 12, 2026	501-1,000	624 contacts →
	Exact match “Somos una empresa multinacional líder en servicios de Consultoría de Oil & Gas, IT, Ingeniería, Recursos Humanos, Head Hunter y Proyectos” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
23	Raba Kistner, INC	Exact match	San Antonio, TX, United StatesHQ recorded Oct 12, 2026	501-1,000	602 contacts →
	Exact match “Founded in 1968, Raba Kistner Inc.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
24	Applied Consultants	Exact match	Longview, TX, United StatesHQ recorded Oct 12, 2026	501-1,000	598 contacts →
	Exact match “Since 1991, Applied Consultants Inc.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase
25	Island Operating Company	Exact match	Scott, LA, United StatesHQ recorded Oct 12, 2026	1,001-5,000	580 contacts →
	Exact match “Improving efficiency and reducing costs, all while meeting safety requirements, is the challenge faced by every operator in the oil and gas industry.” Recorded in the RevenueBase company graph · Oct 12, 2026 · View company records in RevenueBase

RevenueBase SmartSearch

Describe a niche business in your own words. RevenueBase SmartSearch compares the meaning of your description with company business descriptions compiled in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit.

This list uses Exact for “environmental consulting companies for oil and gas”. Each Exact match badge shows membership in that saved search; it is not an individual similarity score or a service-quality rating. Recorded descriptions are shown where available.

Showing 25 of 4,757 environmental consulting companies for oil and gas based in the United States

See the full list, filter by size, metro and specialty, and access 43,493 tracked professional contacts with verified work emails. Direct dials are available where recorded.

Free signup · no credit card

View the full list →

Environmental consulting companies for oil and gas based in the United States at a glance

As of Oct 12, 2026

39.3%Verified-email coverage

23.3Average contacts per company

11-50Median size (employees)

10.4%Largest-city concentration · Houston

Oct 12, 2026Page data refreshed

Companies by employee count

1-10

2,368

11-50

1,605

51-200

550

201-500

140

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 4,757 companies.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies: Company records associated with the United States whose business descriptions match “environmental consulting companies for oil and gas” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch: Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview: The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality: RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
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 displayed company carries at least one verified work email. RevenueBase tracks 43,493 professional contacts with verified work emails across the full matched dataset. 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 October 12, 2026. Lists refresh periodically as the graph is re-checked.
Record context: Company records and descriptions can change. Check the company's website for its current services and locations.

Environmental consulting companies for oil and gas by metro

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “environmental consulting companies for oil and gas”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many environmental consulting companies for oil and gas are there based in the United States?

RevenueBase identified 4,757 company matches for environmental consulting companies for oil and gas associated with the United States as of October 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Langan Engineering & Environmental Services tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most environmental consulting companies for oil and gas?

Houston leads with 497 company records, followed by Denver (87) and Midland (73).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 43,493 professional contacts with verified work emails tracked across these 4,757 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on October 12, 2026.

Ready to reach these companies? Verified emails and direct dials for all 4,757 environmental consulting companies for oil and gas based in the United States. Start with a free account, no credit card.

Download this list →

Related lists

Environmental consulting companies for oil and gas 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 SmartSearch, 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.