Electrical Liner Integrity Survey

	Electrical Liner Integrity Survey Electrical liner integrity surveys, also known as leak location surveys are a post-installation quality control method of detecting leaks in geomembranes. Geomembranes are typically used for large-scale containment of liquid or solid waste. These electrical survey techniques are widely embraced as the state-of-the-art methods of locating leaks in installed geomembranes, which is imperative for the long-term protection of groundwater and the maintenance of water resources. Increasingly specified by environmental regulations, the methods are also applied voluntarily by many site owners as responsible environmental stewards and to minimize future liability. History Electrical liner integrity surveys were initially developed at Southwest Research Institute through funding provided by the U.S. Environmental Protection Agency as a response to the need to control the quality of geomembrane installations. Three technical papers describing the method were published and presented by Southw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Geomembranes A geomembrane is very low permeability synthetic membrane liner or barrier used with any geotechnical engineering related material so as to control fluid (liquid or gas) migration in a human-made project, structure, or system. Geomembranes are made from relatively thin continuous polymeric sheets, but they can also be made from the impregnation of geotextiles with asphalt, elastomer or polymer sprays, or as multilayered bitumen geocomposites. Continuous polymer sheet geomembranes are, by far, the most common. Manufacturing The manufacturing of geomembranes begins with the production of the raw materials, which include the polymer resin, and various additives such as antioxidants, plasticizers, fillers, carbon black, and lubricants (as a processing aid). These raw materials (i.e., the "formulation") are then processed into sheets of various widths and thickness by extrusion, calendering, and/or spread coating. Geomembranes dominate the sales of geosynthetic products, at US$1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Groundwater Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock become completely saturated with water is called the water table. Groundwater is recharged from the surface; it may discharge from the surface naturally at springs and seeps, and can form oases or wetlands. Groundwater is also often withdrawn for agricultural, municipal, and industrial use by constructing and operating extraction wells. The study of the distribution and movement of groundwater is hydrogeology, also called groundwater hydrology. Typically, groundwater is thought of as water flowing through shallow aquifers, but, in the technical sense, it can also contain soil moisture, perma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Geonets A geonet is a geosynthetic material similar in structure to a geogrid, consisting of integrally connected parallel sets of ribs overlying similar sets at various angles for in-plane drainage of liquids or gases. Geonets are often laminated with geotextiles on one or both surfaces and are then referred to as drainage geocomposites. They are competitive with other drainage geocomposites having different core configurations. Manufacturing Geonets are formed by a continuous extrusion process into a netlike configuration of parallel sets of homogeneously interconnected ribs. There are three categories of geonets. The following are illustrated: * ''Biplanar geonets:'' These are the original and most common types and consist of two sets of intersecting ribs at different angles and spacings. The ribs themselves are of different sizes and shapes for different styles. * ''Triplanar geonets:'' These have parallel central ribs with smaller sets of ribs above and beneath mainly for geome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Geocomposites Geocomposite is a composition / combination of two or more geosynthetic materials to perform multiple number of geosynthetic functions for specific civil engineering application(s) the purpose of providing this composition is to minimize the application costs whereas the technical properties of the soil or the geotechnical structure are enhanced. There are five basic functions that can be provided: separation, reinforcement, filtration, drainage, and containment. Geotextile-geonet composites When a geotextile is used on one or both sides of a geonet, the separation and filtration functions are always satisfied, but the drainage function is vastly improved in comparison to geotextiles by themselves. Such geocomposites are regularly used in intercepting and conveying leachate in landfill liner and cover systems and for conducting vapor or water beneath pond liners of various types. These drainage geocomposites also make excellent drains to intercept water in a capillary zone where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Geosynthetic Clay Liner Different types of fabric used for geosynthetic clay liners. Geosynthetic clay liners (GCLs) are factory manufactured hydraulic barriers consisting of a layer of bentonite or other very low-permeability material supported bgeotextilesand/or geomembranes, mechanically held together by needling, stitching, or chemical adhesives. Due to environmental laws, any seepage from landfills must be collected and properly disposed of, otherwise contamination of the surrounding ground water could cause major environmental and/or ecological problems. The lower the hydraulic conductivity the more effective the GCL will be at retaining seepage inside of the landfill. Bentonite composed predominantly (>70%) of montmorillonite or other expansive clays, are preferred and most commonly used in GCLs. A general GCL construction would consist of two layers of geosynthetics stitched together enclosing a layer of natural or processed sodium bentonite. Typically, woven and/or non-woven textile geosyn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]