Improving Performance of Geosynthetics for Containment of Volatile Organic Compounds through the Use of Ethylene Vinyl Alcohol (EVOH)

The inclusion of ethylene vinyl alcohol (EVOH) copolymer by coextrusion into geosynthetic liners would greatly reduce diffusive migration of volatile organic compounds (VOC's). The primary function of a geosynthetic liner system in a geoenvironmental application is containment of liquids and vapor that should not migrate into the surrounding environment. Existing monolithic geomembranes comprised of polypropylene, polyethylene and polyvinylchloride are excellent hydraulic and heavy metal barriers, but are not good barriers to volatile organic compounds that pose a threat to soil, water and air quality. In a composite with polyethylene or polypropylene, EVOH would dramatically improve the capability of geosynthetics to control the diffusion of gases, hydrocarbons and solvents in applications ranging from waste landfills, secondary containment, radon and vapor intrusion barriers and brown field remediation. A comparison of the properties and performance of model geosynthetics incorporating EVOH showed that EVOH improves VOC barrier properties by several orders of magnitude without substantially affecting key form and functionality of existing geomembranes.