What is a Temporary Exposed Geomembrane Cover?
Temporary Exposed Geomembrane Covers (TEGCs) block rainfall from infiltrating into buried waste and generating leachate. RhinoSkin® from Owens Corning®, in particular, is a high-strength geomembrane with high-density polyethylene scrims and both sides are coated with flexible, waterproof low-density polyethylene (LDPE).
What are the benefits to landfills of using these covers?
First and foremost, reduce water treatment costs. Leachate treatment often represents a significant operating cost. TEGCs are synthetic barrier materials with reliable performance and durability to shed precipitation away from contributing to leachate quantity.
Are they easy to install?
They are very easy to install because TEGCs can be prefabricated. More specifically, 12-foot-wide RhinoSkin™ rolls are heat-fusion welded in factory conditions, as opposed to having to measure, cut and weld these in the field. Prefabrication greatly reduces the number of field welds required, thereby reducing the time and labor spent in the field. In addition, the overall weld quality improves with TEGCs by taking advantage of controlled conditions. Once complete, the lightweight and flexible properties of the RhinoSkin™ material allows it to be folded, rerolled and transported to the job site. Depending on the thickness of material used, TEGCs can be fabricated to cover up to an acre with no additional field welding required.
What is the typical service life?
The typical service life is much longer than an alternative daily cover, but significantly easier and less expensive than a final closure cover system. A TEGC has a “sweet spot” between two and seven years of service life with a compelling payback. Typically placed atop a reduced layer of cover soil, a TEGC can be designed for multi-year life expectancy and strategically positioned to cordon off large sloped and flat areas until a permanent closure solution is required.
What results have you seen these systems provide?
RhinoSkin™ has been installed on landfills all over the world. At our own landfill at the Owens Corning Insulation Plant in Newark, Ohio, we could clearly track the specific benefits straight to our operating cost. The rapid and easy installation of the prefabricated RhinoSkin™ panels reduced the estimated time of field sewing or welding by almost 40 percent and offered the added assurance of higher quality seams. The most significant benefit was leachate reduction in excess of 75 percent. The RhinoSkin™ TEGCs were effective in blocking and diverting rainfall that would otherwise infiltrate and generate leachate.
Identifying the right area to use the TEGC, and then making the right choices in design and product selection, can lead to substantial cost savings. There are usually plenty of areas of an operational solid waste management facility that can truly benefit from placement of a TEGC.