Alternative Materials Used As Embankment Fill In Sustainable Engineering Landscape Applications

A suitability study of the use of alternative materials in the construction of a vegetated bund has been carried out by the authors. Basic Oxygen Steel Slag (BOS) and Construction, Demolition and Excavation Waste (CD&EW) were selected as bund core materials based on their local availability and production volume as industrial by-products. A third core section of local sub-soil was also used as a control. The bund was covered with a 200mm thick topsoil layer, mulch, a standard grass mix and a selected range of indigenous shrubs and trees. The key areas studied were the ability of each core material to sustain vegetation, moisture retention and the potential for leachate generation, and potential effects on the local ground and surface waters. The results from tensiometer data and vegetation assessments indicate that BOS and CD&EW are suitable construction materials when used as unbound fill in the core of vegetated bunds. There are no clear discrepancies in the health or growth of vegetation on these alternative materials over conventional sub-soil. An assessment of the leaching characteristics of the materials utilised in the bund also indicate that they present no significant environmental risk in this application.