You’ll find dozens of mentions of geomembranes in the recommendations and standards for mining facilities in most states, but the exact definition of this term isn’t always clear. It’s not the name of a single product or material, but rather an umbrella term including dozens of different materials with some shared characteristics. Assuming that all geomembranes are interchangeable will only lead to costly failures in the challenging mining environment. Don’t let confusion between various geomembrane liner products slow down your selection. Here’s what you need to know about mining geomembranes to make the right selection.
A Part of the Family of Geosynthetics
Geomembranes are part of a larger family of products known as geosynthetics. Geosynthetics are a full range of polymer-based products designed to stabilize soil in some way. Geomembranes in particular are solid planar sheets of material usually extruded or laminated rather than woven. They’re commonly used as liners and containment pads, but they also work well as covers. These geomembranes tend to offer high levels of impermeability to control seepage and leaks. This is an essential feature when dealing with the ground water contamination risks posed by mining waste. With nearly impermeable construction, these geomembranes are also widely used as covers. In addition to controlling the incoming or outgoing flow of water, these materials are also useful as vapor control barriers for areas where evaporation or gas production is an issue.
While each mining geomembrane product varies in its specific features, there are some shared characteristics among the various materials. Most of these features are essential for determining which formulas and designs are right for your project. Common geomembrane characteristics include:
- Flexibility, which is limited by both stiffness and thickness
- The addition of carbon black as an additive to increase resistance against UV degradation
- Low permeability or near impermeability to reduce water loss through the geomembrane as much as possible
- Surface textures to increase grip against the soil and ballast to prevent collapse or erosion
- Stretch resistance rated to a specific amount of weight per square inch or foot
- Reinforcement through the addition of non-woven and woven layers
- Vapor transmission control.
Common Uses Across Industries
Geomembranes are used for far more than just storing and processing mining materials and waste. These durable liners are also popular for controlling potable water flow and storage since they’re non-reactive and available in appropriate food-safe formulations. Sewage treatment facilities also rely on geomembranes of all kinds to safely store and process hazardous waste mixtures. Agricultural facilities widely use these liners to prevent animal waste and field runoff from reaching the water table underground or nearby waterways. While all of these industries and many others make widespread use of geomembranes, the mining industry accounts for approximately 40% of all liner use.
The Importance of Impermeability
The high level of impermeability offered by the extruded and non-woven geomembrane makes it valuable for a wide range of uses, especially in the mining industry. Leach pads and processing ponds tend to contain high concentrations of minerals and metals that are still in the middle of refining. Permeable liners allow too much water to escape, taking along plenty of valuable chemicals and other components. Geomembranes from BTL Liners are designed to offer impermeable performance to minimize seepage as much as possible. Whether you need to preserve a certain solution saturation or are concerned about risks to the water table, these liners provide the water loss control you need.
Only a handful of the most common geomembrane materials are a good fit for mining uses. Choosing the wrong base material will result in a mining geomembrane that breaks down prematurely or costs more than what’s necessary. Minimize maintenance over the lifespan of the storage or processing pond by selecting the right liner. Reinforced polyethylene (RPE) materials are generally considered one of the best options for these kinds of installations.
Not all geomembranes work well in mining applications. Many are better suited for irrigation canals or fishponds thanks to their specific characteristics. If you’re looking for materials that can handle the specific challenges posed by the mining industry, turn to BTL Liners. Our RPE products, such as ArmorPro liners, are designed to withstand the strongest chemical mixtures and harshest environmental conditions.