Methane gas geomembrane permeability

April 1, 2022  |  Q&A: GMA Techline

Q: What is the least permeable geomembrane to methane gas? Regarding the permeability of geomembranes to methane gas, could you send me some technical guidelines?
High pH effects geogrids?

April 1, 2022  |  Q&A: GMA Techline

Q: Can you tell me whether the high pH of curing portland cement (typically ~12.4) might have any impact on the long-term performance of geogrids?
LCC curing effect on geogrids

April 1, 2022  |  Q&A: GMA Techline

Q: Can you tell me whether modest warming of geogrids (e.g., due to heat generated by the curing of lightweight cellular concrete [LCC]) might impact the long-term strength or long-term modulus of geogrids?
Calendared nonwoven geotextiles

April 1, 2022  |  Q&A: GMA Techline

Q: What is the difference between normal nonwoven and calendared nonwoven (both needlepunched) geotextiles? Where can we use calendared nonwoven geotextiles?
GCL-GM geocomposite: Which end is up?

April 1, 2022  |  Q&A: GMA Techline

Q: In a geosynthetic clay liner-geomembrane (GCL-GM) geocomposite, does it make any difference which side of the geocomposite is up: GM or clay?
Impregnation of GCLs

April 1, 2022  |  Q&A: GMA Techline

Q: We are confused with the term “impregnation” as it relates to seaming geosynthetic clay liners (GCLs). There are two types of impregnations: (1) Edge impregnation, and (2) complete nonwoven (cap layer) impregnation of GCLs. How does a manufacturer do this?
NSF 61-certified HDPE geomembranes

April 1, 2022  |  Q&A: GMA Techline

Q: Hi, we are looking for options for NSF 61-certified high-density polyethylene (HDPE) liners for installation in a potable water tank, 95th-percentile concentration of free chlorine in the tank is 1.2 ppm (1.2 mg/L). The current liner (60-mil [1.5-mm] textured HDPE, installed in 1999) is damaged a…
Welding HDPE geomembranes with biogas present

April 1, 2022  |  Q&A: GMA Techline

Q: We are a Brazilian company specializing in biogas plants. We have built a big lagoon biodigester with a high-density polyethylene (HDPE) geomembrane cover. Now the cover is leaking liquid contained in the lagoon: We are organizing the repair procedure, and we would like to first investigate state…
GMA new and renewing members

April 1, 2022  |  Industry News, News

To find out more about these companies and other IFAI members, visit the member directory at www.ifai.com/members.
ACE Geosynthetics wins IAAs in the geosynthetics category

April 1, 2022  |  Industry News

The northern part of a highway interchange project in the Middle East is adjacent to a developing industrial park; a densely populated city is located to the west of the jobsite, and a planned residential area is to the east. Before construction, the roads in this area were always congested. An inte…