Liners geological

The primary characteristic necessary for a liner, cover, or cutoff wall is low permeability, which essentially enables them to slow down the seepage or diffusion of chemicals. Clay is therefore the main material used to construct these containment systems. The thickness and chemical compatibility of containment systems are of concern in assessing the performance of a system. For example, clay liners are constructed as a simple liner that is 2 to 5 ft thick. In composite and double liners, the compacted clay layers are usually between 2 and 5 ft thick, depending on the characteristics of the underlying geology and the type of liner to be installed. Regulations specify that the clay used can only allow water to penetrate at a rate of less than 1.2 in./yr. However, the effectiveness of clay liners can be reduced by fractures induced by freeze-thaw cycles, drying out, and the presence of some chemicals. 

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... 

Kayabali, K. 1997. Engineering aspects of a novel landfill liner material bentonite-amended natural zeolite. Eng Geology 46 105-114. 

Finally, if high-level waste is considered to be hazardous waste under RCRA, requirements on construction, operation, and closure of a disposal facility, including the provision of a liner system, leachate collection and removal system, and leak detection system (see Section 4.2.2), would need to be addressed. Such requirements are impractical at a geologic repository for disposal of high-level waste... 

Double-liner systems proposed by the United States Environmental Protection Agency guidelines. The leachate collection layer is also considered to function as the geomembrane protection layer, (a) The flexible membrane liner, FML/composite double liner, (b) FML/compacted soil double liner (after Mitchell, 1986). With the kind permission of the Geological Society. 

Voudrias, E.A. (2002). The concept of a sorption chemical barrier for improving effectiveness of landfill liners. Waste Management and Research, 20 251-258. Wilson, M J. (1986). Mineral weathering processes in podzolic soils on granitic materials and their implications for surface water acidification. Journal of the Geological Society of London, 143 691-697. 

Unstable Areas. Karst terrain will be avoided. Before a landfill can be located in a geologically unstable area it must be demonstrated to the appropriate state agency that the integrity of the liner system and other structural components will not be disrupted. 

Compacted clay layer, an important facility of the landfill liner system, minimizes and even prevents the geological environment from the landfill body pollution. During a landfill operation, the... 

A surfaee impoundment may eonsist of an exeavated pit, a structure formed with dikes, or a eombination thereof The eonstruetion is similar to that discussed above for landfills in that the bottom and walls should be impermeable to liquids and provision must be made for leaehate colleetion. The chemical and mechanical challenges to liner materials in surface impoundments are severe so that proper geological siting and construction with floors and walls composed of low-permeability soil and clay are important in preventing pollution from these installations. 

Mollard, S. j., Jefford, C. E., Staff, M. G. Browning, G. R. J. 1996. Geomembrane landfill liners in the real world. In Bentley, S. P. (ed.) Engineering Geology of Waste Disposal. Geological Society, London, Engineering Geology Special Publications, 11, 165-170. 

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