Open-cast mine operators must restore the landscape after minerals have been extracted. Although this can be a cost-intensive process, repurposing existing excavators and conveyors to transport overburden and topsoil can be a wise commercial decision.
By Andreas Scholz
Open-cast mining is essential for extracting materials like copper, gold, iron, limestone and gravel, but it does result in disturbed landscapes that need to be returned to close to their original condition. The approach to recultivation has evolved considerably: once it was acceptable to create lakes for recreation, now the emphasis has shifted towards the reinstatement of agricultural land and encouraging biodiversity.
Millions of tonnes of loess soil and overburden are required to recultivate an open-cast mine. Restoring the site to its original condition may take decades. It requires a significant investment, but the financial burden can be alleviated by adapting existing mining equipment such as bucket excavators, spreaders, and conveyor systems for restoration purposes.
Recultivation represents an opportunity to repurpose existing mining equipment and use it to redevelop the site following the cessation of mining operations. There are clear parallels between the material movements in a working mine and those involved in the recultivation of the land. For example:
Together, these mining systems can stabilise the terrain, create smooth slopes, and layer topsoil where necessary, forming the foundation for reforestation, agricultural rehabilitation, or other land restoration efforts.
Utilising mining equipment in recultivation projects brings multiple benefits for mine operators. Key advantages include:
Redeploying mining machinery like excavators, spreaders, and conveyors can be more cost-effective than employing trucks for soil transportation. Reusing existing infrastructure minimises the need for new capital investment, reducing overall project costs and carbon footprint.
There is no need for additional truck fleets, manpower, or training if you reuse mining equipment. The existing workforce is large enough to implement your recultivation plan and they have the necessary skills to operate the equipment safely and efficiently.
Mining equipment like bucket wheel excavators and spreaders is designed for heavy-duty operations and can last for decades, attributes necessary for long-term recultivation projects. Reliability is proven as this equipment has served for years before being used for the purpose of recultivation.
European legislation, such as Directive 2006/21/EC, is creating the impetus for the recultivation of open-cast mines to create a valuable asset. This is being driven by multiple global factors, including climate change and food security, which make the recovery of agricultural land and the improvement of biodiversity increasingly important.
Mining operators are already benefiting from the use of mine equipment in a recultivation context. One example is the Hambuch open-cast mine in Germany. Hambach produces 40 million tonnes of lignite per year and will remain operational until 2030, but recultivation is already taking place alongside mining operations. Integrating both processes allows unconsolidated sediments to be transported via conveyor from the active mine to the areas where recultivation is already underway. These sediments are used to refill the mine so that new recultivation landscapes can be created in parallel with coal extraction. Agriculture, reforestation and the creation of special habitats, including waterways, are all part of the plan.
Using large-scale, automated mining equipment in recultivation projects is a pragmatic and cost-efficient way of aligning with economic, environmental, and legislative priorities. It minimises the need for new capital investment and ensures that disturbed landscapes are effectively restored, supporting ecological balance and providing valuable land for future generations.
