Double-liner and leachate collection system

FIGURE 26.1 Schematic of a double-liner and leachate collection system for a hazardous landfill. (Adapted from U.S. EPA, Training Module Introduction to Land Disposal Units, EPA530-K-05-014, U.S. Environmental Protection Agency, Washington, DC, September 2005.)... 

Double Liners and Leachate Collection Systems for Hazardous Waste Disposal Units Subparts M, N, and O Land Treatment, Landfills, and Incinerators... 

Waste disposal is a serious problem for many chemical plants. The EPA initiative that has greatly curtailed land disposal has had a great effect on waste disposal. The 1984 Resource Conservation and Recovery Act (RCRA) amendments have also made it more difficult to dispose of solid wastes. In addition, RCRA required all interim status hazardous-waste facilities to meet ground-water monitoring and insurance requirements by late 1985. This included hazardous-waste surface impoundments. Since 1988, a double liner and leachate collection system have also been required. 

The site conditions for an on-site landfill, such as location, geology, hydrogeology, physiography, climate, and so on, should also be suitable. Landfill should meet the minimum technology requirements and regulations for hazardous waste landfills such as double liners and leachate collection and removal systems, leak detection systems, closure procedures and final cover, and construction quality assurance.59... 

Modem hazardous-waste landfills typically have dual leachate collection systems, one located between the two impermeable liners required for the bottom and sides of the landfill, and another just above the top liner of the double-liner system. The upper leachate collection system is called the primary leachate collection system, and the bottom is called the secondary leachate collection system. Leachate is collected in perforated pipes that are embedded in granular drain material. 

The numerical results indicate superior performance of composite liner systems over CCLs in preventing hazardous constituent migration out of the unit and maximizing leachate collection and removal. Consequently, owners of new units subject to the double-liner requirement of FISWA are now installing composite bottom liners or double composite liner systems.3... 

The landfill must have a double liner system that can prevent any migration of wastes out of the landfill to the adjacent soil, groundwater, or surface water. The liner system must include a leachate collection and removal system between the two liners. 

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