Archives

GCL Overlaying

April 1st, 2025

Q: Can you provide information about overlaying a new GCL on hydrated and damaged GCL? A: This is more complex than one might first think—particularly from the standpoint of instability. The friction angle (ASTM D5321) of hydrated GCL to new GCL might be in the single digits (i.e., 8+/-2 degrees residual or less). Depending on […]

Read More

The GMA Techline

October 1st, 2020

Moderated by George R. Koerner Puncture after NDT Q: I would like your opinion on the fate of punctures in the air channel leftover from nondestructive air channel tests (NDTs), specifically in regard to sealing the air channels to prevent leachate or water ingress. We are particularly concerned with this situation on a landfill cover […]

Read More

The GMA Techline answers all

August 1st, 2018

UV Weathering of Geotextiles Q: My firm is providing construction quality assurance services for a landfill cell expansion. We are having an issue with our contractor and are going to be in a position of having 8 ounces/square yard (271 g/m2) of nonwoven geotextile exposed for a period of time, which exceeds the seven-day limit […]

Read More