Engineering Considerations and Case Histories of Landfill Intermediate Covers

Installation of intermediate covers on landfills prior to final closure has gained significant attention in the solid waste industry due to stringent regulations on landfill gas emissions and increased costs associated with leachate treatment during landfill operations. The main purposes of installing an intermediate cover are to control landfill odors, reduce stormwater infiltration, and improve landfill gas collection efficiency. The soil cover and exposed geomembrane cover are commonly used as landfill intermediate covers, and recently, the engineered turf intermediate cover has been developed as another alternative. A comparison is made to show the advantages and disadvantages of each type of intermediate cover. Major engineering considerations associated with intermediate covers are discussed. The results of wind tunnel tests conducted on the engineered turf and exposed geomembrane intermediate covers are presented to support the wind uplift evaluation. Case histories of the engineered turf intermediate cover are provided for the first time in the literature.