In the double-liner system shown in Figure 17.11, what is the layer of geotextile over the geonet in the leak detection, collection, and removal (LDCR) system used for?
Explanation
This question requires interpretation of a diagram of a modern landfill liner and understanding the specific function of the geotextile when used in conjunction with a geonet in a drainage layer.
Other questions
What is the liquid called that forms when waste materials in a landfill interact with moisture from rainfall and snow?
According to the U.S. Environmental Protection Agency (EPA), what is the maximum required hydraulic conductivity (k) for clay liners in solid-waste disposal sites?
Which of the following is NOT listed as a criterion specified by the U.S. Environmental Protection Agency (EPA) for soil used in clay liners?
What is the term for fabric-like material made from polymers such as polyester, polyethylene, and polypropylene, used in civil engineering construction?
Which of the following is NOT listed as one of the five major functions of geosynthetics?
What are geotextiles formed from filaments or short fibers arranged in a loose web and then bonded together called?
What term is used to express the cross-plane drainage capability of a geotextile, calculated as the hydraulic conductivity for cross-plane flow divided by the geotextile's thickness?
What term is used to express the in-plane drainage capability of a geotextile, calculated as the hydraulic conductivity for in-plane flow multiplied by the geotextile's thickness?
What is the typical range of hydraulic conductivity for geomembranes, leading them to be considered 'essentially impermeable'?
What is the primary function of geonets in landfill applications?
Before about 1982, what was a primary characteristic and limitation of single clay liner systems for landfills?
In a modern double-liner system, what is the system located between the primary and secondary liners called?
In a double-liner system, what is the maximum leachate head that the primary leachate collection system must generally be able to maintain?
If a granular drainage layer is used in a primary leachate collection system or LDCR system, what is its required minimum thickness according to general guidelines?
What is the minimum required hydraulic conductivity (k) for a granular drainage layer or a geosynthetic used in a leachate collection system?
What is a composite liner, as described in the context of modern landfill design, made of?
What is the typical minimum grade provided for the bottom of a large landfill site to allow leachate to flow to a sump by gravity?
What is the primary purpose of placing a cap on a landfill after it is complete?
The schematic diagram of a landfill cap layering system in Figure 17.17 shows a compacted clay cap with a hydraulic conductivity less than or equal to what value?
For how long does the U.S. Environmental Protection Agency (EPA) recommend that leachate removal continue for hazardous-waste landfill sites after closure?
For a given compaction effort, how does the hydraulic conductivity (k) of a clay liner change as the molding moisture content increases towards the optimum moisture content?
According to the research by Benson and Daniel (1990), how does the magnitude of hydraulic conductivity (k) of a compacted clayey soil change with the size of the clods for a similar compaction effort?
What is the minimum percentage of fines (fine silt and clay-sized particles) that soil for a clay liner should have, according to U.S. Environmental Protection Agency (EPA) criteria?
What is the recommended lower limit for the Plasticity Index (PI) for soils used in clay liners, and above what approximate PI value do soils become difficult to work with in the field?
Which specific type of nonwoven geotextile is described in the text as being thick and having high in-plane hydraulic conductivity?
What is the primary purpose of the filtration function when a geotextile is placed between a coarse-grained and a fine-grained soil layer?
Which type of field seam for geomembranes involves using a solvent adhesive to overlap two sheets, followed by applying roller pressure?
In a double hot air or wedge seam, what approximate temperature should be reached to melt the opposing surfaces of the geomembrane before applying pressure?
What is the minimum required thickness for geomembranes used for landfill lining?
What is the first step in the procedure developed by Daniel and Benson (1990) to establish moisture content-unit weight criteria for clayey soils to meet hydraulic conductivity requirements?
Which of the four major categories of waste material was generated in the largest quantity in the United States in 1984, according to Table 17.1?
According to Table 17.1, what was the approximate quantity of hazardous waste generated in the United States in 1984?
When compacting a clay soil for a liner, if two samples have a similar dry unit weight, which one will have a lower hydraulic conductivity?
Which category of geosynthetic is formed by the continuous extrusion of polymeric ribs at acute angles to each other and has large openings in a netlike configuration?
What is one of the main materials from which geotextiles are usually made, due to the rapid decay of natural fabrics?
What component is placed over the gravel layer in a single clay liner system to protect the holes in the perforated pipes?
In the secondary leak detection, collection, and removal (LDCR) system shown in Figure 17.14, which liner does the plastic pipe penetrate for the removal of leachate by means of pumping?
For gravity monitoring of the leak detection, collection, and removal (LDCR) system as shown in Figure 17.15, which liner does the monitoring pipe penetrate?
In the landfill cap layering system shown in Figure 17.17, what is the minimum thickness specified for the geomembrane?
What is a typical value for the permittivity (P) of geotextiles, which measures cross-plane hydraulic capability?
What is a typical transmissivity (T) value for a nonwoven geotextile, which measures in-plane drainage capability?
Which of the following polymer types is listed in Section 17.5 as a thermoplastic polymer used for geomembranes?
Which field seam type for geomembranes is described as being mostly used in dense thermoset material, such as isoprene-isobutylene?
In an extrusion weld lap seam, what is extruded between the two surfaces to be joined?
What issue during the construction of a compacted clay liner can cause a substantial increase in the overall hydraulic conductivity, as demonstrated by the Houston trial pad where the value increased from about 10 to the power of -8 to 10 to the power of -4 cm/sec?
What is the maximum size for particles or chunks of rock that should be contained in soil intended for use as a clay liner, according to the U.S. Environmental Protection Agency (EPA) criteria?
Which of the four major uses of geotextiles involves increasing the load-bearing capacity of the soil?
In a modern double-liner system as shown in Figure 17.10, the Leak Detection, Collection, and Removal (LDCR) system is made of what material?
According to the schematic in Figure 17.17 for a landfill cap, what is the required hydraulic conductivity for the drainage layer?