Site Closure Designs

Pilbara, Western Australia (WA)

OKC was appointed by an iron ore mine to create final landform designs for six waste dumps at the site. OKC developed a waste sampling plan to collect samples from the dumps. The collected materials were analysed for geochemical and geotechnical characteristics to confirm erosional stability and check for the presence of reactive materials. Based on the material properties and local climate data, OKC designed a series of store-and-release type landforms to reduce reliance on surface water drainage post-closure.

The configurations of outer embankments comprised short-linear slopes on small dumps and a long-concave profiles for a larger landform.  Erosion modelling confirmed the design met closure criteria over long time frames. Earthworks were optimised using specialist landform design software and used to provide detailed reshaping material quantities and closure liability estimates.