Ecolab Inc. provides water, hygiene, and infection prevention solutions and services in the United States and internationally. The company operates through three segments: Global Industrial; Global Institutional & Specialty; and Global Healthcare & Life Sciences. The Global Industrial segment offers water treatment and process applications, and cleaning and sanitizing solutions to manufacturing, food and beverage processing, transportation, chemical, metals and mining, power generation, pulp and paper, commercial laundry, petroleum, refining, and petrochemical industries. Its Global Institutional & Specialty segment provides specialized cleaning and sanitizing products to the foodservice, hospitality, lodging, government and education, and retail industries. The Global Healthcare & Life Sciences segment offers specialized cleaning and sanitizing products to the healthcare, personal care, and pharmaceutical industries, such as infection prevention and surgical solutions, and end-to-end cleaning and contamination control solutions under the Ecolab, Microtek, and Anios brand names. In addition, the company provides pest elimination services to detect, eliminate, and prevent pests, such as rodents and insects in restaurants, food and beverage processors, hotels, grocery operations, and other commercial segments including education, life sciences, and healthcare customers. Further, it offers colloidal silica for binding and polishing applications in semiconductor, catalyst, and aerospace component manufacturing, as well as chemical industries; and products and services that manage wash process through custom designed programs, premium products, dispensing equipment, water and energy management, and reduction, as well as real time data management. It sells its products through field sales and corporate account personnel, distributors, and dealers. Ecolab Inc. was founded in 1923 and is headquartered in Saint Paul, Minnesota.

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.

Exponent, Inc., together with its subsidiaries, operates as a science and engineering consulting company in the United States and internationally. The company operates in two segments, Engineering and Other Scientific, and Environmental and Health. The Engineering and Other Scientific segment provides services in the areas of biomechanics, biomedical engineering and sciences, buildings and structures, civil engineering, construction consulting, data sciences, electrical engineering and computer science, human factors, materials and corrosion engineering, mechanical engineering, polymer science and materials chemistry, thermal sciences, and vehicle engineering. The Environmental and Health segment offers services in the areas of chemical regulation and food safety, ecological and biological sciences, environmental and earth sciences, and health sciences. The company offers approximately 90 technical disciplines to solve pressing and complicated challenges facing stakeholders. It serves clients in chemical, construction, consumer products, energy, food, beverage and nutrition, government, life sciences, insurance, manufacturing, technology, industrial equipment, transportation, and other sectors of the economy. The company was formerly known as The Failure Group, Inc. and changed its name to Exponent, Inc. in 1998. The company was founded in 1967 and is headquartered in Menlo Park, California.

Bowman Consulting Group Ltd. provides a range of real estate, energy, infrastructure, and environmental management solutions in the United States. It offers civil and site engineering services, such as conceptual land planning, environmental consulting and permitting, planning/zoning and entitlements, roadway and highway designs, erosion and sediment designs, stormwater management designs, construction administration, traffic studies, floodplain studies, and utility relocation designs; and commissioning and energy efficiency services comprise construction observation, direct systems functional performance testing, system development readiness checklist, post occupancy review, review of construction documents, deferred/seasonal functional testing, final commissioning report, and commissioning review of submittals. The company also provides construction management services, including constructability review, value engineering, budgeting and cost estimating, interagency and utility coordination, onsite observation and report evaluation, public communication and outreach, and resident engineer services, as well as bid solicitation, documentation, and preparation services; and environmental consulting services consisting of wetlands and waters of the U.S. delineations, natural resources inventories, wildlife and vegetation surveys, threatened and endangered species surveys, endangered species conservation and management, wetland creation and enhancement design, NEPA documentation, section 404/401 permitting and compliance, NPDES permitting, and phase I environmental site assessment. In addition, it offers landscape architecture, land procurement and right-of-way acquisition, structural engineering, surveying and geospatial engineering, and transportation and water resources engineering services, as well as mechanical, electrical, and plumbing engineering services. The company was incorporated in 1995 and is headquartered in Reston, Virginia.

Mistras Group, Inc. provides technology-enabled asset protection solutions in the United States, other Americas, Europe, and the Asia-Pacific. The company offers non-destructive testing services; inline inspection for pipelines; and plant condition management software. It also provides maintenance and light mechanical services, such as corrosion removal, mitigation and prevention, insulation installation and removal, electrical, heat tracing, industrial cleaning, pipefitting, and welding; engineering consulting services primarily for process equipment, technologies, and facilities; and utilizes scaffolding and rope access to access at-height and confined assets. In addition, the company offers certified divers for subsea inspection and maintenance; unmanned aerial, land-based, and subsea systems for inspection applications; online condition-monitoring solutions; quality assurance and quality control solutions for new and existing metal and alloy components, materials, and composites. Further, it builds monitoring systems, as well as provides inspection, maintenance, monitoring and data services; and Web-based solutions. Additionally, the company designs, manufactures, and sells acoustic emission sensors, instruments, and turnkey systems for monitoring and testing materials, pressure components, processes, and structures; and ultrasonic testing equipment. It serves oil and gas, aerospace and defense, fossil and nuclear power, power generation and transmission, civil infrastructure, manufacturing, industrial, public infrastructure, petrochemical, transportation, and other process industries, as well as infrastructure, research, and engineering industries. Mistras Group, Inc. was founded in 1978 and is headquartered in Princeton Junction, New Jersey.

Perma-Fix Environmental Services, Inc., through its subsidiaries, operates as an environmental and technology know-how company in the United States. The company through Treatment and Services segments. The Treatment segment offers nuclear, low-level radioactive, mixed waste, hazardous and non-hazardous waste treatment, and processing and disposal services through treatment and storage facilities. This segment is also involved in the research and development activities to identify, develop, and implement waste processing techniques for problematic waste streams. The Services segment provides technical services, including professional radiological measurement and site survey of government and commercial installations; health physics services; integrated occupational safety and health services; and consulting, engineering, project and waste management, environmental, decontamination and decommissioning (D&D) field, technical and management personnel and services; and waste management services. This segment also offers nuclear services, including D&D of government and commercial facilities, including engineering, technology applications, specialty services, logistics, transportation, processing, and disposal; and license termination support, such as project management, planning, characterization, waste stream identification and delineation, remediation/demolition, compliance demonstration, final status survey, reporting, transportation, disposal and emergency response. In addition, it maintains, services, maintains, calibrates, and sources health physics, IH and customized nuclear, environmental, and occupational safety and health instruments. The company provides its services to research institutions, commercial companies, public utilities, and governmental agencies through direct sales to customers or through intermediaries. Perma-Fix Environmental Services, Inc. was incorporated in 1990 and is headquartered in Atlanta, Georgia.