A geomembrane may sound like a medical experiment gone wrong, but its uses and applications are both varied and fascinating. Geomembranes are synthetic membrane liners or barriers used to control fluid migration in a manmade project, structure, or system. They are made from relatively thin continuous polymeric sheets that are sometimes made from the infusion of geotextiles with asphalt, elastomer, or polymer sprays. This means that their applications to geotechnical engineering and other industrial clients are endless.
Geomembranes are being used in environmental, hydraulic, transportation, and oil and gas applications as well as the waste industry. The most common type are the continuous polymeric sheets. When larger geomembranes are needed, they are thermally or chemically melted together at the seams for strength and durability. The size of the geomembrane is completely customizable, so they are can be as small as a backyard fish pond or as large as a football field if necessary.
Why Might You Need a Geomembrane?
Whether you are managing an industrial site or maintaining a recreational pond, a geomembrane offers significant benefits:
- Environmental Protection: Prevent soil and groundwater contamination from hazardous substances.
- Cost Savings: Reduce maintenance costs by providing a long-term solution to water containment and pollution prevention.
- Regulatory Compliance: Meet stringent environmental regulations and avoid costly penalties.
- Enhanced Water Management: Minimize water loss due to seepage, enhancing overall efficiency in irrigation or water storage.
Common Uses of a Geomembrane Liner
To get a better idea of what you can use a geomembrane for, here are just some of the most common uses:
- As liners for potable or reserve water (e.g., safe shutdown of nuclear facilities)
- As fish pond liners
- As liners for waste liquids (e.g., sewage sludge), radioactive or hazardous waste liquid
- As liners for the agriculture industry
- As liners for various waste conveyance canals
- As liners for primary, secondary, and/or tertiary solid-waste landfills and waste piles
- As linings for emergency spillways
- As waterproofing liners within tunnels and pipelines
- To contain and transport liquids in trucks
- To contain and transport potable water and other liquids in the ocean
- Beneath highways to prevent pollution from deicing salts
- Beneath and adjacent to highways to capture hazardous liquid spills.
Basically, geomembranes are used wherever loss of material cannot be allowed, be that clean water, wastewater, vapor, soil, hazardous materials, or any other substance that doesn’t need to escape its designated space. Because flowing, pooling, frozen, and standing liquids (and even vapors) can be so devastating if not managed properly, these geomembranes have allowed industries to continue to develop and support many more projects than previously done before.
Geomembranes vs. Other Materials
Geomembrane liners, specifically those made from high-density polyethylene (HDPE) or reinforced polyethylene (RPE), offer superior performance compared to traditional liner options like clay or concrete. Their superiority stems from a range of advantageous properties, including their impermeability, durability, cost-effectiveness, and ease of installation.
1. Impermeability
One of the most important functions of any liner is to prevent leakage and seepage. HDPE and RPE geomembranes are engineered to be highly impermeable, creating a robust barrier against liquids and gases. Their low permeability rates are far superior to compacted clay liners, which are prone to cracking and shrinking over time. Concrete can also develop cracks due to temperature changes, chemical attack, or settling. In contrast, HDPE and RPE liners provide a continuous, seamless barrier.
2. Chemical Resistance
Both HDPE and RPE liners have excellent resistance to a broad range of chemicals, making them ideal for use in industrial waste containment, mining operations, and agricultural applications. They resist corrosion and degradation even in harsh environments. Conversely, clay can be eroded by certain chemicals, and concrete is susceptible to acid attack and sulfate damage.
3. Durability and Longevity
HDPE and RPE liners are known for their exceptional durability. They are UV-resistant and can withstand extreme temperatures, ensuring long-term stability even under harsh environmental conditions. Their flexibility allows them to adapt to ground movement and settling without cracking. In contrast, concrete and clay liners are more rigid and can crack under similar conditions, reducing their effectiveness over time.
4. Cost-Effectiveness
From a cost perspective, geomembrane liners offer a more economical solution than concrete. HDPE and RPE liners are lightweight, reducing transportation costs. They can also be prefabricated to specific dimensions, simplifying the installation process and minimizing labor costs. Clay and concrete liners typically require extensive site preparation and skilled labor, driving up costs.
5. Ease of Installation
Installing HDPE and RPE liners is relatively straightforward. They can be welded together to form large, continuous sheets with minimal seams, which reduces the risk of leakage. Installation is also quicker compared to laying concrete or compacting clay layers. This ease of installation translates into significant time savings, particularly for large projects.