Implementation

How we do it…

Our goal is to reduce the cost and environmental risk from mining waste landforms. We do this by providing a high quality service in the manner and timescale required by our Clients. To be successful, a DumpSolver waste dump plan requires a close partnership with each client. Our objective is to provide a meaningful and practical waste dump solution, which minimises costs and environmental risk but takes full account of each client’s specific requirements within appropriate safety and environmental guidelines.

A site visit is strongly recommended, particularly for work undertaken on an existing mining operation. In such cases, it is important that mine planning and environmental personnel on site have joint ownership in the process and DumpSolver thoroughly understand all potential issues.

For a project that is still in the planning stage, the potential rock dump footprints must be optimised as soon as possible to evaluate their interaction with and impact on other surface infrastructure. As a rule of thumb, adding a kilometre haul to a waste dump site may increase the mine operating cost by $0.50 per cubic metre. This may be offset by additional capital costs to establish other permanent infrastructure elsewhere. There is a balance and DumpSolver’s powerful constraint engine will rapidly and quantifiably assess the possible permutations and combinations to help find the best solution.

Constraints may vary over time. An area that is a restricted dump site today may become available in a few years time. One such example could be a pit void that has been worked out, and at some point become available for backfill. Another could be a delay in dump permitting.

The computation for finding the overall lowest cost dumping solution, that complies with all environmental requirements and physical constraints to dumping, can be complex but is based on rigorous evaluation of haul truck performance and costs as well as other fixed and area costs. Area costs relate to required pre- and post-mining activities on the landform. DumpSolver handles all of the inputs and variables to derive the lowest cost, environmentally compliant but practical solution.

A conceptual waste dump plan may be presented as a block model or as crest and toe strings that depict the final landform. A detailed dump plan is usually presented as a sequenced block model which relates to the waste mining schedule. The sequenced blocks are used to prepare crest and toe strings for quarterly or annual increments to define dump layouts which incorporate appropriate and practical haul ramp strategies. Dumping plans may involve encapsulation requirements, and such things as rock armouring. The subsequent designs and reports are intended to guide the operators through the required production process.

Invariably the volumes and nature of the waste rock actually coming out of the pit will vary to some extent from that originally planned. DumpSolver’s planning process includes an assessment of the risk of potential variation in the quantity, quality and timing of waste and, where possible, makes allowances to provide a low risk, flexible dumping plan.

Finally, we recognise that the best dump plan will have failed if it is not followed. To ensure the dump plans become an integral part of the mining operation and the savings are locked in, we provide an on-going service to monitor the progressive dump layout by comparing it to an actual dump survey, or aerial fly-over. Since mine plans always change, the dump layout must be flexible to account for minor changes. If the dump is being continually monitored during construction, the mitigation risk and closeout costs will be more closely understood. The overall cost reduction achieved will more than offset the small ongoing cost of our monitoring service.