Waste Management, Inc. is a holding company. The Company, through its subsidiaries, provides waste management environmental services. The Company's Solid Waste business is operated and managed locally by its subsidiaries that focus on geographic areas and provides collection, transfer, recycling and resource recovery, and disposal services. The Company develops, operates and owns landfill gas-to-energy facilities in the United States. The Company's segments include Tier 1, which comprises areas in the Southern United States; Tier 2, which comprises areas located in the Midwest and Northeast United States, and Tier 3, which encompasses the remaining areas, including the Northwest and Mid-Atlantic regions of the United States and Eastern Canada. The Company owns or operates 252 landfill sites. It manages 298 transfer stations that consolidate, compact and transport waste.