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Water woes addressed by newly lined reservoir

April 1, 2015

Chowchilla pistachio farm By Raphael Bennett Introduction Situated on 600 acres of pistachio farmland located in the northern San Joaquin Valley of California, this farm management conglomerate wanted a solution to its water accessibility issues. Due to the current water climate in California, the water loss problem with the reservoir as it previously stood had …

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Reconstructing and relining Nottingham Lake high in the Rockies

February 1, 2015

Replacing a 32-year-old liner. By Bart Ewing and Duff Simbec Introduction Nottingham Lake is nestled high in the Rocky Mountains and has been the pride of Avon, Colo., for as long as anyone can remember. Tourists and residents use the lake for winter recreation and for boating, fishing, and swimming in the summer. It serves as …

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Part 1: The first double geomembrane liner 40 years later

First constructed in June 1974 and has been in continuous service since then. By J.P. Giroud and J.P. Gourc Introduction The first double liner with two geomembranes was constructed in June 1974 and has been in continuous service since then. The double-lined structure is a water reservoir located in Pont-de-Claix, near Grenoble in southeastern France. …

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Design considerations for GCLs in leach pad liner systems

October 1, 2014

By Chris Athanassopoulos and Mark Smith Introduction Traditionally, leach pad lining systems have consisted of a single geomembrane liner placed directly over a prepared subgrade of locally available soil or, occasionally, compacted clay. Heap fills are most commonly constructed by placing a layer of highly-permeable drainage stone (overliner) over the geomembrane, usually with perforated drainage …

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Designing to minimize geomembrane leakage

August 1, 2014

By Abigail Beck Introduction Specifying a geomembrane as a barrier system component for a containment facility seems like a straightforward task. Once a geomembrane is specified, the containment facility won’t leak, right? The reality behind geomembrane installations is that the ultimate performance of an installed geomembrane ranges from completely ineffective to highly effective. What creates …

Ohio EPA addresses wrinkles in landfill FML construction

March 14, 2014

Agency issues guidance document Introduction The Ohio Environmental Protection Agency delivered a document via a March 14 news release regarding wrinkles in FMLs used in landfill construction. Rule requirements Flexible membrane liner (FML) is a component of the composite liner system required at municipal, industrial, and residual solid waste landfills. The municipal and industrial solid …

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9090 testing on LLDPE and HDPE

February 1, 2014

From the GMA Techline 9090 testing on LLDPE and HDPE I would like to know if the 9090 testing was done strictly with 40-mil liners or was it done to multiple thickness liners, HDPE or LLDPE? The Pennsylvania Department of Environmental Protection (Pa.DEP) is requiring I produce it with the chemical compatibility chart to get …

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Geomembrane UV protection?

From the GMA Techline RE: Geomembrane UV protection? I have a question regarding geomembranes and I hope you can help. If a geotextile is placed over a geomembrane, is that considered sufficient to provide long-term UV protection for the geomembrane? Any input is greatly appreciated. Thank you, (Walter | Pennsylvania) Reply: It’s good to hear …

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Allowable construction loading on geosynthetics

From the GMA Techline RE: Allowable construction loading on geosynthetics Hello Dr. Koerner, On the question of allowable construction loading on geosynthetics, Daniel and Koerner (2007) state: “If not specifically excluded in the regulations, and if agreed on by the CQA engineer, all-terrain vehicles (ATVs) or equipment with smooth, oversized tires of maximum ground contact …

New installation guidelines from FGI/IAGI

December 5, 2013

For factory-fabricated lightweight geomembranes The Fabricated Geomembrane Institute (FGI) and the International Association of Geosynthetic Installers (IAGI) have collaborated to produce Guidelines for Installation of: Factory Fabricated Lightweight <0.64mm (25 mil) Thickness. The guidelines are arranged in four parts: 1. General: Guideline scope, references, submittals 2. Products: Geomembrane materials, quality control, geomembrane arrival at project …