Abstract
Mine closure planning is typically performed separately after a completed life of mine plan. The separation of knowledge, technology, and responsibilities between these plans prevents a holistic approach to mine planning, and opportunities to improve the value of the project as it moves towards closure are rarely explored or realized.
The key objective for this case study was to determine the best “planning for closure” case for an operation with less than five years remaining production. Detailed physicals for landform rehabilitation were quantified and costed using modern mining software and integrated with the mine, processing, and closure plans to form a base case scenario. The base case provided a consistent auditable platform upon which to explore value-adding options and assess overall project values for various “what if “ scenarios.
Scenarios were run to test cashflow sensitivity to the sale price, mine phase sequencing, haulage cost, and “as-dumped” landform design. The underlying aim for each case was to minimize dump reshaping cost, reduce the closure footprint, and maximize overall “real” cashflow .
This paper demonstrates that by integrating planning tools into the whole mining value chain, all the way through to final closure, practical and informed decisions can be made many years before final rehabilitation is initiated. This process adds real value to the mining operations and enables informed decisions to be made on future investments, and guides future cash flow management strategies.