Storage
Brine ponds used for storage have a different goal than those used for mining - their job is to maintain a stable solution within specific parameters, perhaps for potential re-use in industries like fracking or natural gas storage in salt caverns. In these cases, the focus is on minimizing water loss, and pond covers are often the most reliable and cost-effective solution to achieve that goal. Since these covers are tightly sealed to prevent escape of gases and fumes, they must have the same high chemical resistance and resiliency as the pond liner itself.
Material compatibility
If you’re working with an existing brine pond, it’s possible to install a flexible geomembrane cover even if the materials aren’t the same, but it’s harder to maintain an airtight seal. If you need to ensure air or gas can leak out between the cover and liner, it’s important to use the same material, or ones that are compatible for both elements. Since a complete enclosure for long-term brine control, with minimal evaporation, requires a tight seal. RPE liners and compatible covers can be sealed together with heat or solvent-based adhesives, giving you plenty of options for simplifying installation as much as possible.
Temporary
Even in evaporative brine ponds, removable covers are often used for occasional protection against large amounts of precipitation. A single inch of precipitation in a 1-acre evaporation pond represents a setback of over 27,000 gallons of water that must now be evaporated. To prevent this, flexible, lightweight RPE covers can be quickly and easily deployed, either manually or aided by machine, then secured along the edges temporarily with ballasts or spikes. Sump pumps attached to the liner collect and deflect accumulated rainfall, which never has a chance to reach the pond. In case of severe storms or high winds, these covers can be anchored to the sides of a pond or even paired with floating ball ballasts to prevent shifting or lifting. Other geomembranes aren’t suitable for this use, since they’re heavier, less flexible, and often more prone to tearing and mechanical damage.
Aside from rainfall, another common risk for managers of brine ponds is wind. Whether high winds are a seasonal issue or only show up during storms, wind can create a shearing effect that picks up surface brine and spreads across the surrounding area. If the area includes valuable ecosystems such as rivers, wetlands, or farmland, exposure to toxic spray can lead to fines and expensive, long-term remediation efforts.
Safety
Especially in the case of long-term storage, ponds frequently become attractive to wildlife, specifially birds, seeking a safe refuge to rest. In many parts of the world, irrigation ponds contain such high levels of selenium that water birds are known to pass birth defects on to their offspring. Some salt solutions are so concentrated that they are often toxic even without additional contaminants. In these cases, brine pond covers offer the simplest and most effective solution to problems with wildlife access.
Liners for brine ponds are required almost everywhere, including where dry salt is stored for use on roads during winter weather. Covers are often required as well, although the specs may only stipulate the use of a simple waterproof tarp. BTL Liners impermeable geomembranes more than meet those standards and offer significantly more effective containment.
