dfills may be publicly or privately owned.
             In 1992, the Environmental Protection Agency estimated that municipal landfills, those owned by municipalities or which accepted municipal waste, constituted 20 percent of the sites on the National Priorities List, and that municipalities were otherwise "involved" as generators, transporters or arrangers of 25 percent of the National Priorities List sites. The sites on the list represent national localities that pose a hazard to the environment. Another study showed that of the 163 MSW landfills studied 90 percent had groundwater contamination and 45 percent had surface water contamination. These figures demonstrated the need for stricter federal regulation and enforcement of municipal solid waste landfills.
             The main emphasis of federal regulations has shifted to protect ground water and prevent pollution from inadequately designed and operated municipal solid waste landfills. Landfills are an important part of our nation's system for managing garbage and wastes, the government must ensure their safe and efficient operation. While federal regulation was formerly in the background, beginning in 1993, the EPA regulations under Resource Conservation and Recovery Act, set forth in 40 CFR Part 258, became effective to govern all privately and publicly-owned municipal solid waste landfill units. MSWL
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