Difficulties associated with the construction and maintenance of conventional landfill barrier caps has prompted a number of alternative capping solutions. One particular example is an evapotranspiration (ET) landfill cap. These covers rely on the manipulation of water balance components rather than a barrier approach in order to minimise the infiltration of water into the landfill. The overall ET cover design philosophy and process is significantly different from that employed in the construction of conventional covers.

Currently Hanson Australia, in collaboration with Melbourne University, is working through the design and research of an ET cover at Wollert landfill in Victoria. This paper presents the background and objectives of the project, a summary of the progress to date and intended future research. An insight is given into cover material and plant selection and required field, laboratory and glasshouse trials.