Severe erosion compromises Florida road

April 1, 2014  |  Products

TRM called on for erosion control in reconstruction of St. Joe Road By Jill Pack Introduction As Tropical Storm Debby made its way to Florida in June 2012, residents prepared for the power outages, supply shortages, and flooding that typically accompany storms of this predicted magnitude. As Debby m…
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Ohio EPA addresses wrinkles in landfill FML construction

March 14, 2014  |  Products

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 mu…
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NCMA’s Design Manual for Segmental Retaining Walls

February 1, 2014  |  Products

Submittal requirements for polyester geogrid reinforcement By R. Lance Carter and Michael Bernardi Adopted by the NCMA Segmental Retaining Wall & Hardscape Products Committee Editor’s note Lance Carter and Michael Bernardi, although competitors, felt the need to remind geosynthetic users, …
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Geocomposite drain flow capacity: ISO VS. ASTM

February 1, 2014  |  Products

From the GMA Techline RE: Geocomposite drain flow capacity: ISO VS. ASTM We are evaluating geocomposite drain products for underdrainage beneath geomembrane-lined ponds. This is an international project—we are considering non-North American products for which the hydraulic properties are based…
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Apparent opening size (ASTM D4751) for geotextiles

February 1, 2014  |  Products

From the GMA Techline RE: Apparent opening size (ASTM D4751) for geotextiles Our specification calls for a geotextile with an AOS of #50 U.S. sieve (0.3mm). I understand that unlike the rest of the technical property values, AOS is specified by the maximum value (i.e., MaxARV not MARV). Please advis…
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Silt fence

February 1, 2014  |  Products

GMA techline answers from Bob Koerner RE: Silt fence I have read M288 and understand the different levels of material specifications for highway applications. Is there another category that can be sold to the public that does not have to meet the specifications for highway applications? For example,…
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More silt fence

February 1, 2014  |  Products

From the GMA Techline RE: More silt fence Also, I have another question regarding geo properties and their specifications. Permittivity is an indicator of how well water can flow through the fabric. AOS is an indicator of the soil particle size held back by the fabric. The permittivity specification…
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9090 testing on LLDPE and HDPE

February 1, 2014  |  Products

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 …
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Cover veneer stability and freezing

February 1, 2014  |  Products

From the GMA Techline RE: Cover veneer stability and freezing I received a question recently from a regulator on whether freezing conditions could result in reduced interface shear strength between a geocomposite drainage layer and a geomembrane for a cover system with three feet of overlying soil. …
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Geomembrane UV protection?

February 1, 2014  |  Products

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, (Wal…
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