Waste Management, Inc., through its subsidiaries, engages in the provision of environmental solutions to residential, commercial, industrial, and municipal customers in the United States and Canada. It offers collection services, including picking up and transporting waste and recyclable materials from where it was generated to a transfer station, material recovery facility (MRF), or disposal site; and owns and operates transfer stations, as well as owns, develops, and operates landfill facilities that produce landfill gas used as renewable natural gas for generating electricity. As of December 31, 2022, the company owned or operated 254 solid waste landfills, five secure hazardous waste landfills, 97 MRFs, and 337 transfer stations. It also provides materials processing and commodities recycling services at its MRFs, where cardboard, paper, glass, metals, plastics, construction and demolition materials, and other recycling commodities are recovered for resale or redirected for other purposes; recycling brokerage services, such as managing the marketing of recyclable materials for third parties; and other strategic business solutions. In addition, the company offers construction and remediation services; services related with the disposal of fly ash, and residue generated from the combustion of coal and other fuel stocks; in-plant services comprising full-service waste management solutions and consulting services; and specialized disposal services for oil and gas exploration and production operations. The company was formerly known as USA Waste Services, Inc. and changed its name to Waste Management, Inc. in 1998. Waste Management, Inc. was incorporated in 1987 and is headquartered in Houston, Texas.

Republic Services, Inc., together with its subsidiaries, offers environmental services in the United States and Canada. It is involved in the collection and processing of recyclable, solid waste, and industrial waste materials; transportation and disposal of non-hazardous and hazardous waste streams; and other environmental solutions. Its residential collection services include curbside collection of material for transport to transfer stations, landfills, recycling centers, and organics processing facilities; supply of recycling and waste containers; and renting of compactors. The company also engages in the processing and sale of old corrugated containers, old newsprint, aluminum, glass, and other materials; and provision of landfill services. It serves small-container, large-container, and residential customers. The company was incorporated in 1996 and is based in Phoenix, Arizona.

Clean Harbors, Inc. provides environmental and industrial services in the United States and internationally. The company operates through two segments, Environmental Services and Safety-Kleen Sustainability Solutions. The Environmental Services segment collects, transports, treats, and disposes hazardous and non-hazardous waste, such as resource recovery, physical treatment, fuel blending, incineration, landfill disposal, wastewater treatment, lab chemicals disposal, and explosives management services; and offers CleanPack services, including collection, identification, categorization, specialized packaging, transportation, and disposal of laboratory chemicals and household hazardous waste. This segment also provides industrial maintenance and specialty industrial services; and utilizes specialty equipment and resources that performs field services. The Safety-Kleen Sustainability Solutions segment provides pickup and transportation services for hazardous and non-hazardous containerized waste for recycling or disposal; machine cleaning and maintenance, and disposal and replenishment of clean solvent or aqueous fluids; and vacuum services to remove solids, residual oily water, and sludge and other fluids from customers' oil/water separators, sumps, and collection tanks, as well as removes and collects waste fluids found at large and small industrial locations, including metal fabricators, auto maintenance providers, and general manufacturers. This segment also manufactures, formulates, packages, distributes, and markets lubricants and other automotive products. Clean Harbors, Inc. was incorporated in 1980 and is headquartered in Norwell, Massachusetts.

Tetra Tech, Inc. provides consulting and engineering services in the United States and internationally. The company operates through two segments, Government Services Group (GSG) and Commercial/International Services Group (CIG). The GSG segment offers early data collection and monitoring, data analysis and information management, science and engineering applied research, engineering design, project management, and operations and maintenance services; and climate change and energy management consulting, as well as greenhouse gas inventory assessment, certification, reduction, and management services. This segment serves federal, state, and local governments; and development agencies in water resources analysis and water management, environmental monitoring, data analytics, government consulting, waste management, and a range of civil infrastructure master planning and engineering design markets. The CIG segment provides early data collection and monitoring, data analysis and information management, feasibility studies and assessments, science and engineering applied research, engineering design, project management, and operations and maintenance services; and environmental remediation and reconstruction services, and industrial water treatment services. This segment serves natural resources, energy, and utilities markets, as well as sustainable infrastructure master planning and engineering design for facilities, transportation, and local development projects. Tetra Tech, Inc. was founded in 1966 and is headquartered in Pasadena, California.

Fluor Corporation provides engineering, procurement, and construction (EPC); fabrication and modularization; operation and maintenance; asset integrity; and project management services worldwide. The company operates through Energy Solutions, Urban Solutions, Mission Solutions, and Other segments. The Energy Solutions segment provides solutions to the energy transition markets, including asset decarbonization, carbon capture, renewable fuels, waste-to-energy, green chemicals, hydrogen, nuclear power, and other low-carbon energy sources. It also provides consulting services, including feasibility studies, process assessments, and project finance structuring; and a range of services for small modular reactor technologies, conventional and advanced nuclear reactor technologies. This segment serves the production and fuels, chemicals, LNG, power markets, chemicals and petrochemical industries. The Urban Solutions segment offers EPC and project management services to the infrastructure, advanced technologies, life sciences, and mining and metals industries. This segment also provides staffing services to the company and third-party clients with technical, professional, and craft resources on a contract or permanent placement basis. The Mission Solutions segment offers technical solutions to the U.S. and other governments. It also delivers solutions for nuclear security and operation, nuclear waste management, and laboratory management; and operation and maintenance, logistics, EPC, and life support solutions for mission-critical facilities across U.S. military service organizations. This segment offers site management, environmental remediation, and decommissioning for nuclear remediation at governmental facilities, as well as services to commercial nuclear clients. Fluor Corporation was founded in 1912 and is headquartered in Irving, Texas.

Mirion Technologies, Inc. provides radiation detection, measurement, analysis, and monitoring products and services in the United States, Canada, the United Kingdom, France, Germany, Finland, China, Belgium, Netherlands, Estonia, South Korea, and Japan. It operates through two segments, Medical and Technologies. The Medical segment offers radiation oncology quality assurance and dosimetry solutions; patient safety solutions for diagnostic imaging and radiation therapy centers; radiation therapy quality assurance solutions for calibrating and verifying imaging and treatment accuracy; and radionuclide therapy products for nuclear medicine applications, such as shielding, product handling, medical imaging furniture, and rehabilitation products. This segment supports applications in medical diagnostics, cancer treatment, practitioner safety, and rehabilitation. The Technologies segment focuses on addressing critical radiation safety, measurement, and analysis applications; and provides personal radiation detection, identification equipment, and analysis tools. The company's products and solutions also include nuclear medicines, dosimeters, contamination and clearance monitors, reactor instrumentation and control equipment and systems, medical and industrial imaging systems and related accessories, alpha spectroscopy instruments, alpha/beta counting instruments, and gamma spectroscopy detector systems; and electrical penetration, cancer diagnostics, software, and other services. It serves hospitals, clinics and urgent care facilities, dental and veterinary offices, radiation treatment facilities, OEMs for radiation therapy, laboratories, military organizations, government agencies, industrial companies, power and utility companies, reactor design firms, and NPPs. The company was formerly known as Global Monitoring Systems, Inc. and changed its name to Mirion Technologies, Inc. in January 2006. The company was incorporated in 2005 and is headquartered in Atlanta, Georgia.

NV5 Global, Inc. provides technology, conformity assessment, consulting solutions, and software applications to public and private sector clients in the infrastructure, utility services, construction, real estate, environmental, and geospatial markets in the United States and internationally. It operates through three segments: Infrastructure; Building, Technology & Sciences; and Geospatial Solutions. The company offers site selection and planning, design, water resources, structural engineering, land development, surveying, power delivery, building code compliance, and other services. It is also involved in the construction of highways, bridges and tunnels; development of rail and light rail systems; provision of services related to street and roadway construction; and construction materials testing and engineering, geotechnical engineering and consulting, and forensic consulting services. In addition, the company provides governmental outsourcing and consulting, and technical outsourcing services; and geospatial data analytic and mapping services, as well as remote sensing services. Further, it offers mechanical, electrical, and plumbing design; commissioning; energy performance, management, and optimization; climate change and reducing CO2 emissions; building program management; acoustical design consulting; and audiovisual–security and surveillance–information technology–data center services. Additionally, the company provides various services, such as investigating and analyzing environmental conditions, and recommending corrective measures and procedures; occupational health and safety services; radiation exposure and protection, and nuclear safety and industrial hygiene analyses services; hydrogeological modeling and environmental programs. The company was formerly known as NV5 Holdings, Inc. and changed its name to NV5 Global, Inc. in December 2015. NV5 Global, Inc. was founded in 1949 and is headquartered in Hollywood, Florida.

Montrose Environmental Group, Inc. operates as an environmental services company in the United States, Canada, and internationally. The company operates in three segments: Assessment, Permitting and Response; Measurement and Analysis; and Remediation and Reuse. The Assessment, Permitting and Response segment provides scientific advisory and consulting services to support environmental assessments; environmental emergency response and recovery; toxicology consulting and environmental audits and permits for current operations; facility upgrades; new projects; decommissioning projects; and development projects. This segment also offers technical advisory and consulting services, including regulatory compliance support and planning, environmental, ecosystem and toxicological assessments, and support during responses to environmental disruptions. The Measurement and Analysis segment tests and analyzes air, water, and soil to determine concentrations of contaminants, as well as the toxicological impact of contaminants on flora, fauna, and human health. Its services include source and ambient air testing and monitoring, leak detection, and advanced analytical laboratory services, such as storm water, wastewater, and drinking water analysis. The Remediation and Reuse segment provides engineering, design, implementation, and operations and maintenance services primarily to treat contaminated water, remove contaminants from soil, or create biogas from waste. The company serves financial, oil and gas, utilities, construction, automotive, real-estate, midstream energy, manufacturing, commodities, petrochemical, food and beverage, telecommunications, and engineering industries, as well as local, state, provincial, and federal government entities. Montrose Environmental Group, Inc. was founded in 2012 and is headquartered in North Little Rock, Arkansas.