Traditional landfill final cover systems work well at many sites. However, alternative cover systems are often considered to reduce closure and/or maintenance costs or to delay permanent closure of the landfill until a later date when waste settlement and gas generation rates have decreased significantly.
This presentation is related to using exposed geomembrane covers at landfill facilities either as long-term interim covers or as final covers.This presentation provides a brief overview of the history of using exposed geomembrane covers at landfill sites starting with an exposed geomembrane cover that was constructed in Delaware in 1997. The evolution of exposed geomembrane covers including development of solar caps and geomembranes overlain by synthetic turf is briefly discussed. The presentation focuses on the technical, regulatory, and financial feasibility of utilizing exposed geomembrane covers for closure of landfills. In particular, details, advantages, and limitations of exposed geomembrane covers are discussed. The advantages of exposed geomembrane covers include lower capital and maintenance costs, reduced greenhouse gas emissions, fewer issues with cover slope stability and settlement, better stromwater quality, and ability to capture airspace created by waste settlement in the future. Designers and manufacturers have also made significant progress in addressing concerns with exposed geomembranes including concerns with aesthetics, limited cover access, limited design life, anchoring to resist wind uplift, increased runoff volumes and velocities, and potential for damage by hail and birds. These concerns and available solutions are discussed in the presentation.