Coal Combustion Residuals Application Solutions

Tough Products for Tough Demands

Studies have shown that coal combustion residual(CCR) leachates are more chemically severe than what what was previously studied a decade ago. This means new technologies are needed to safely contain these harsher leachates. 


Touch leachates require tough products.



What are coal combustion residuals?

Commonly known as coal ash, CCRs are created during the power generation process and can include fly ash, bottom ash, boilerslag, and flue gas desulfurization (FGD) waste. CCRs contain trace concentrations of heavy metals and therefore cannot be dumped or stored where rainwater can leach the metals. Liner systems are typically used to contain the coal combustion by-products and protect them from leaching into the environment.

As utilities look for solutions that will mitigate groundwater contamination, GCLs have become an essential part of the solution.

Industry-leading solutions

As the worldwide leader in geosynthetic clay liner (GCL) production and innovation, CETCO is using our proprietary products to tackle coal ash. A GCL is an engineered hydraulic barrier consisting of high-swelling sodium bentonite clay bonded to a geosynthetic material or encapsulated between layers of geosynthetic materials. Mass-produced under factory-controlled conditions ensures a uniform product that consistently performs and exceeds the quality of conventional compacted clay barriers.


GCLs can extend the construction season beyond that previously attainable with CCLs. A number of studies have revealed that CCLs can undergo increases of several orders of magnitude change in hydraulic conductivity when exposed to freeze-thaw cycling. Upon thawing, CCLs can create cracks whereas GCLs can withstand 20 freeze-thaw cycles with no deterioration in hydraulic conductivity. 


Featuring our proprietary, high-density needlepunching construction, CETCO GCLs encapsulate high-quality bentonite or our patented polymer-modified bentonite between geotextiles to produce GCLs with industry-leading shear strength performance to meet the demands commonly found in coal ash applications. CETCO GCLs outperform compacted clay liners in both performance and ease-of-installation. 

Expansive and customizable solutions

GCLs offer coal ash landfills with superior protection over compacted clay liners (CCLs). As the pioneer in geosynthetic clay liners, utilities are relying on CETCO GCLs for protection: 

  • RESISTEX® GCL: Polymer-modified bentonite GCLs are engineered to provide the highest level of chemical compatibility for hydraulic barrier performance in extremely aggressive leachate environments. Our RESISTEX GCL family offers compatibility with a wide range of pH, electrical conductivity, and ionic strengths that are common to mining liquids. CETCO recommends project-specific compatibility testing for the proper selection from the RESISTEX family of GCLs.
  • BENTOMAT®  GCL: Sodium bentonite-based GCLs provide an excellent hydraulic barrier in applications where leachate in direct contact with the GCL is relatively non-aggressive, or in composite lining applications where the GCL is overlain by a thermally welded geomembrane and hydrates from the uptake of innocuous moisture from the subgrade. 

The insight and help you need

Our experience and application knowledge provide you insight into project design. In addition to offering high quality products, CETCO provides unparalleled technical support. Our multi-disciplinary technical staff are recognized subject matter experts, fluent in our products and technologies with application experience throughout the world.


Our expertise includes:

  • Leachate sampling and analysis
  • Compatibility testing
  • Equivalency calculations
  • Shear strength testing
  • QA/QC testing
  • Specification development
  • Product selection


CETCO can partner with the owner or engineer to provide meaningful assistance and guidance during the design process. Contact us to get started. 

CETCO - Pioneer and leader in environmental products

CETCO is the leader and pioneer in cutting-edge environmental solutions. Around the globe for the last half-century, our innovative teams of clay mineralogists, chemists, and polymer scientists transform ordinary minerals into extraordinary technology to solve day-to-day problems worldwide.



    Drop-In Spec
    We build all of our GCLs to be compliant with GRI-GCL3 and their guide specifications can be found for use on the Geosynthetic Institute website.