1. What are Reinforced Composite Polyethylene (RCPE) and Woven Coated Polyethylene (WCPE) geomembranes?
Reinforced Composite Polyethylene geomembranes are built from a HDPE woven scrim core and coated with an engineered LLDPE/LDPE coating. Depending on the application and project needs, different thicknesses of products can be manufactured. The last coating is the lamination of an LDPE film to the core to improve performance. Specifiers and end users can rely on the Geosynthetic Research Institute’s GRI-GM30 to define RCPE products and minimum manufacturing quality control requirements. A sister product to the RCPE is the Woven Coated Polyethylene (WCPE) barrier which does not include a film and can be produced in thicknesses ranging from 12-40 mils.
2. Where are RCPEs and WCPEs installed in the landfill industry?
RCPE and WCPE products can be broken into two categories based on thickness. RCPE geomembranes, which are greater than 30 mils in thickness, are best suited for stormwater and wastewater storage liner applications and, in some instances, may be used in landfill final cover applications. WCPE barriers, which are less than 30 mils in thickness, are best suited for alternative daily cover applications and temporary rain covers.
3. What are the benefits and why do they work in these applications?
First, RCPE & WCPE membranes are extremely durable, often with double the puncture strength that you would get from a polymeric-style product. Second, these products can be prefabricated in a controlled environment, thereby reducing the on-site installation and deployment time by about a third or less. This delivers installation cost savings for the owner and more material per truckload compared to traditional materials.
4. How do RCPEs and WCPEs deliver these benefits?
Large panels up to an acre in size (depending on the thickness) can be created in a factory. The unique structure of the RCPE/WCPE barrier or membrane allows the product to be folded and rolled without damaging it. Upon deployment, these large panels can be installed quickly, covering large areas and minimizing field seaming and testing. The speed of installation reduces the contractor’s risk and expedites the construction process.
5. Are RCPEs and WCPEs validated by independent industry professionals?
RCPE geomembranes are supported by a number of industry specifications, such as GRI-GM30, which specifies the manufacturing quality control requirements, and GRI-GM19b, which describes the minimum seam strengths. In addition to these specifications, there are numerous ASTM methods that can be used to measure the properties of RCPE/WCPE geomembranes and barriers. There are also supporting test methods such as air lance testing (ASTM D4437) and peel and shear strength tests (ASTM D7747) to evaluate the seams.
To learn more about these products, go to rhinoskin.com. Owens Corning strives to work with our fabricator network to deliver materials on-site in as little as one week. For a list of fabricators, visit the Fabricated Geomembrane Institute website at fabricatedgeomembrane.com.