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.

Waste Connections, Inc. provides non-hazardous waste collection, transfer, disposal, and resource recovery services in the United States and Canada. It offers collection services to residential, commercial, municipal, industrial, and exploration and production (E&P) customers; landfill disposal services; and recycling services for various recyclable materials, including compost, cardboard, mixed paper, plastic containers, glass bottles, and ferrous and aluminum metals. The company owns and operates transfer stations that receive compact and/or load waste to be transported to landfills or treatment facilities through truck, rail, or barge; and intermodal services for the rail haul movement of cargo and solid waste containers in the Pacific Northwest through a network of intermodal facilities. In addition, it provides E&P waste treatment, recovery, and disposal services for waste resulting from oil and natural gas exploration and production activity, such as drilling fluids, drill cuttings, completion fluids, and flowback water; production wastes and produced water during a well's operating life; contaminated soils that require treatment during site reclamation; and substances, which require clean-up after a spill, reserve pit clean-up, or pipeline rupture. Further, the company offers leasing services to its customers. Waste Connections, Inc. was founded in 1997 and is based in Woodbridge, Canada.

American Water Works Company, Inc., through its subsidiaries, provides water and wastewater services in the United States. It offers water and wastewater services to approximately 1,700 communities in 14 states serving approximately 3.5 million active customers. The company serves residential customers; commercial customers, including food and beverage providers, commercial property developers and proprietors, and energy suppliers; fire service and private fire customers; industrial customers, such as large-scale manufacturers, mining, and production operations; public authorities comprising government buildings and other public sector facilities, such as schools and universities; and other utilities and community water and wastewater systems. It also provides water and wastewater services on military installations; and undertakes contracts with municipal customers, primarily to operate and manage water and wastewater facilities, as well as offers other related services. In addition, the company operates approximately 80 surface water treatment plants; 540 groundwater treatment plants; 175 wastewater treatment plants; 53,700 miles of transmission, distribution, and collection mains and pipes; 1,200 groundwater wells; 1,700 water and wastewater pumping stations; 1,100 treated water storage facilities; and 74 dams. The company was founded in 1886 and is headquartered in Camden, New Jersey.

Watts Water Technologies, Inc., together with its subsidiaries, supplies products and solutions that manage and conserve the flow of fluids and energy into, through, and out of buildings in the commercial, industrial, and residential markets in the Americas, Europe, the Asia-Pacific, the Middle East, and Africa. The company offers residential and commercial flow control and protection products, including backflow preventers, water pressure regulators, temperature and pressure relief valves, thermostatic mixing valves, leak detection and protection products, commercial washroom solutions, and emergency safety products and equipment for plumbing and hot water applications. It also provides heating, ventilation, and air conditioning and gas products comprising commercial boilers; water heaters and heating solutions; hydronic and electric heating systems for under-floor radiant applications; custom heat and hot water solutions; hydronic pump groups for boiler manufacturers and alternative energy control packages; and flexible stainless-steel connectors for natural and liquid propane gas in commercial food service and residential applications. In addition, the company offers drainage and water re-use products, such as drainage products, engineered rainwater harvesting solutions for commercial, industrial, marine, and residential applications; connected roof drain systems; and water quality products that include point-of-use and point-of-entry water filtration, conditioning, and scale prevention systems for commercial, marine, and residential applications. The company sells its products to plumbing, heating, and mechanical wholesale distributors and dealers; original equipment manufacturers; specialty product distributors; and do-it-yourself and retail chains, as well as wholesalers and private label accounts. Watts Water Technologies, Inc. was founded in 1874 and is headquartered in North Andover, Massachusetts.

Select Water Solutions, Inc., together with its subsidiaries, provides water management and chemical solutions to the energy industry in the United States. The company operates through three segments: Water Services, Water Infrastructure, and Chemical Technologies. The Water Services segment provides water-related services, including water sourcing, water transfer, flowback and well testing, water containment, fluids hauling, water monitoring, and water network automation; technology solutions comprising hydrographic mapping, water volume and quality monitoring, remote pit and tank monitoring, leak detection, asset and fuel tracking, and automated-equipment services, as well as various surface rental equipment and workforce accommodation services. The Water Infrastructure segment engages in the recycling, gathering, transferring, and disposal of water through a network of permanent pipeline infrastructure, semi-permanent pipeline infrastructure, water recycling facilities, earthen pits, water sources, and SWDs; provides solids management services; and develops, builds, and operates semi-permanent and permanent infrastructure solutions. The Chemical Technologies segment provides technical solutions, products, and services related to chemical applications in the oil and gas industry. This segment develops, manufactures, and manages logistics; and provides chemicals used in hydraulic fracturing, stimulation, cementing, and well completions for pressure pumpers and oil and gas producers, as well as offers production chemical solutions for underperforming wells, corrosion and scale monitoring, chemical inventory management, well failure analysis, and lab services. It primarily serves oil and gas producers. The company was formerly known as Select Energy Services, Inc. and changed its name to Select Water Solutions, Inc. in May 2023. Select Water Solutions, Inc. was incorporated in 2016 and is headquartered in Houston, Texas.

Pure Cycle Corporation provides wholesale water and wastewater services in the United States. It operates in two segments, Wholesale Water and Wastewater Services; and Land Development. The company engages in the wholesale water production, storage, treatment, and distribution systems; wastewater collection and treatment systems; development of master-planned community; and construction and leasing of single-family homes. It serves domestic, commercial, and industrial customers. The company was incorporated in 1976 and is based in Watkins, Colorado.

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.

Quest Resource Holding Corporation, together with its subsidiaries, provides solutions for the reuse, recycling, and disposal of various waste streams and recyclables in the United States. The company provides disposal and recycling services for motor oil and automotive lubricants, oil filters, scrap tires, oily water, goods destruction, food waste, meat renderings, cooking oil and grease trap waste, plastics, cardboard, metal, glass, mixed paper, construction debris, as well as a large variety of regulated and non-regulated solid, liquid, and gas wastes. It offers antifreeze and windshield washer fluid, dumpster and compacting equipment, and other minor ancillary services. In addition, the company offers landfill diversion services. Its services focus on the waste streams and recyclables from big box, grocers, and other retailers; automotive maintenance, quick lube, dealerships, and collision repair; transportation, logistics, and internal fleet operators; manufacturing plants; multi-family and commercial properties; restaurant chains and food operations; and construction and demolition projects. The company markets its services to automotive, manufacturing, hospitality and retail, construction and demolition, and commercial and multi-family property management industries through direct sales force and strategic partnerships. The company was formerly known as Infinity Resources Holdings Corp. and changed its name to Quest Resource Holding Corporation in October 2013. Quest Resource Holding Corporation is headquartered in The Colony, Texas.