Study on overburden environmental capacity loss control in multi-horizon mining of coal-associated resources

This study aims to elucidate the mechanisms and control pathways of overburden environmental capacity loss during multi horizon mining of coal associated resources. In response to the coordinated development of coal, uranium, coalbed methane, and oil and gas resources in typical basins, the responses to overburden environmental disturbances induced by multi horizon resource development were analyzed. The concept of overburden environmental capacity was introduced to characterize the response limit and stability capacity of the geological environment under multi-horizon mining. A theoretical and technical framework for controlling environmental capacity loss was developed around the key processes of identification, assessment, control, and decision making. The results show that repeated mining and high-intensity disturbance intensify overburden movement, fracture propagation, and surface subsidence, thereby inducing instability of key strata load-bearing structures. The coupled evolution of stress, fracture, seepage, and energy fields further weakens the environmental carrying capacity of the overburden. A three-tier evaluation system was established by integrating near, intermediate, and far field disturbance criteria, capacity grading assessment, and identification of strongly disturbed zones. A technical pathway combining comprehensive assessment of capacity loss with global sensitivity analysis was developed. With minimization of environmental capacity loss as the optimization objective, the proposed framework supports optimization of mining layouts and proactive risk prevention and control. This study provides a theoretical basis and technical support for the safe, efficient, and coordinated development of coal associated resources and for green and low carbon mining.