Subsidence is common over underground mines. Inefficient subsidence management may lead to fatal injury of miners while surface subsidence may affect the environment such as changing morphology of land settlements, interrupting the hydrologic environment as well as damaging infrastructures and surrounded residents.
The Company integrates subsidence management into mine plans and then submits to related government agencies for approval. Since the mine subsidence movement can be predicted, Centennial, a subsidiary of the Company operating underground mines in Australia, has frequently performed risk assessment on subsidence. The assessment results are then integrated with a geological model to formulate the subsidence management plan to minimize possible subsidence impact. Through the implementation, subsidence monitoring has been undertaken over the application areas to access subsidence impacts. The actual impacts have been compared against the estimated impacts and used further to refine the subsidence model and finally improve the subsidence management plan.