Solid Waste Management: USA Lined Landfilling Reliability 1

Historically, municipal solid waste disposal has been conducted by disposal on low-value lands where the wastes were burned in open pits. Beginning in the 1950s, in some more developed areas, the landfilling of municipal and industrial wastes occurred in “sanitary” landfills. Sanitary landfills differed from the open-pit burning and disposal since burning was no longer allowed, and each day’s waste was covered with a thin layer of soil. This soil layer was designed to reduce, but not necessarily eliminate, releases of odor and prevent vermin from entering into the waste. The sanitary landfill does not address the pollution of groundwaters by landfill leachate (garbage juice). Beginning in the 1980s, in some developed countries, the disposal in municipal landfills of large amounts of highly hazardous industrial wastes was prohibited. In the USA, these so-called “hazardous” wastes had to be detoxified and disposed of in lined hazardous waste landfills. The municipal and industrial so-called “non-hazardous” wastes were to be disposed of in municipal landfills. In the early 1990s, the US Environmental Protection Agency (US EPA) adopted Subtitle D landfilling regulations for disposal of municipal solid waste. This approach is being used today, where there is an attempt, through the use of inexpensive bottom liners and landfill covers, to initially isolate the waste from moisture in a “dry tomb” approach. A minimum Subtitle D landfill is a plastic sheeting and compacted clay lined landfill that, at best, only postpones when groundwater pollution occurs. It has been known from the beginning that the “dry tomb” Subtitle D landfill disposal system for municipal solid waste (MSW) is a fundamentally flawed approach for providing groundwater quality and environmental protection from waste-associated constituents for as long as the wastes will be a threat to public health, groundwater quality and the environment. Many of the municipal solid waste components in today’s Subtitle D “dry tomb” landfills will be a threat to public health, groundwater resources and the environment, effectively, forever. With proper construction, the plastic sheeting and compacted clay liners can prevent groundwater pollution for a short period of time compared to the time that the wastes will be a threat to cause pollution. While the US EPA, as part of adopting Subtitle D regulations, assumed without adequate evaluation that the eventual failure of the liner system to prevent leachate from passing through it, leading to groundwater pollution, would be detected by the groundwater monitoring system used, it has been known since the late 1980s that the groundwater monitoring systems used at Subtitle D landfills, which are based on vertical monitoring wells spaced 30 or more meters apart, are highly unreliable in detecting leachate pollution of groundwater before widespread pollution occurs.