Geosynthetic Clay Liners

Geosynthetic clay liners (otherwise known as GCLs) are hydraulic barriers typically consisting of a layer of natural or processed sodium bentonite (or similar low-permeability material) ‘sandwiched’ between geotextile fabric and/or other geomembranes.  They are mechanically held together by needle stitching and/or chemical adhesives.

Sodium Bentonite (or just Bentonite) is composed predominantly of montmorillonite or other expansive clay and is the conventional material used in most GC liners. A common GCL installation typically consists of two layers of geotextile stitched together to enclose the bentonite, hence the layer of bentonite is protected by the geotextile on both sides. Once hydrated, the bentonite expands and forms a hydraulic barrier.

The use of a geosynthetic clay liner (GCL) is often seen as an alternative to compacted clay liners. The bentonite in the GCL can swell and form a low permeability layer, providing hydraulic protection equivalent to several feet of compacted clay. This makes the GC liners ideal for composite liner systems, landfills, and reservoir liners.

As the leading GCL manufacturer, IEC Covers has engineered GCL liners for numerous environmental containment applications such as landfills, mining, stormwater, and wastewater retention basins. They provide long-lasting resistance to degradation from both physical and environmental factors and are an excellent alternative to conventional compacted clay liners. They are easy and relatively quick to install, and in most cases provide a better and less expensive alternative when compared to clay.

Typical GC Liner applications include:

• Secondary containment
• Landfill liners and caps
• Mine tailings storage
• Wastewater ponds and lagoons
• Canals, stormwater impoundments and wetlands

Geosynthetic clay liners (GC Liners) pricing can vary depending on project size and location and can be influenced by fluctuating raw material costs. For more information on geosynthetic clay liners (GCLs), please contact IEC.