The Case for Using Specialized Geomembranes in Waste Ponds

For centuries, engineers have overcome environmental challenges by implementing specialized tools and techniques designed for each specific problem. In some cases, new tools are developed as deficiencies in older solutions are discovered. A hammer, for instance, is an effective tool for small-scale constructions, but simply isn’t enough when dealing with something as large as a skyscraper or bridge. The same basic principal applies to waste containment construction projects. While a HDPE geomembrane works wonders for fluid impermeability, specialized geomembranes have been created that are more effective in the long-term for dealing with waste ponds containment and covers.

The benefits of specialized waste pond liner for containment: Integrated Drainage Solution

Waste pond liners take on multiple roles for containment, including basin lining and as a cover to reduce the spread of foul odors and reduce the risk of contamination. For the basin lining itself, options include using clay or geocomposite/geonet materials (if clay is unavailable). Geocomposites and geonet materials provide superior performance and can be cost effective, they introduce challenges from an interface friction, specification conformance, and installation perspective. Some of these challenges can be overcome with AGRU’s Integrated Drainage System (IDS), which is a Subtitle D-compliant containment system that incorporates an advanced drainage structure within the geomembrane component. By combining multiple layers—each with its unique benefits—into one product, you have access to a containment solution that also delivers significant cost savings.

A system like IDS incorporates drainage and environmental containment performance into a single layer and reduces the need for separate drainage materials, representing significant cost savings. IDS also incorporates a higher factor of safety for steep-slope stability and is about 15% faster to install than traditional containment systems. Common applications include double-lined ponds, reservoirs, and pits as well as containment pads for landfills and coal combustion residuals. Because the drainage and liner are integrated into a single product, there are fewer rolls to ship, unload, and store on-site.

The benefits of specialized waste pond liner for containment: Conductive Liner Covers

Reasons to cover a pond include thermal retention, which is useful for keeping the water warm and active during winters, and odor control—the prevention of offensive odors from spreading to the nearby populous. Evaporation protection is essential for waste ponds with fluids that have the potential to evaporate. Dust and particulate protection is necessary to ensure that nearby compounds don’t mix with the waste pond. Finally, some waste ponds rely on floating islands. These floating treatment systems are specially designed to consume organic waste, nitrogen, contaminants, and wastewater.

There are many specialty liners that are well-suited to serve as a pond cover. Covers made with conductive liner carry all the benefits of a HDPE, with the additional benefit of being able to dynamically test for leaks using spark testing per ASTM D7240. The test involves sweeping the area with a brush-like test wand to locate points where the capacitor discharges through a leak. When the system senses the discharge current, it is converted to a visible spark and audible alarm. Conductive liner is implemented for improved quality control processes by removing the reliance on the human eye for post-installation inspections.