TITLE:
Classification of Karst Water Disasters beneath the Lower Coal Group and Prevention and Control Technologies in the Huaibei and Huainan Coalfields
AUTHORS:
Zhigang Xie, Feng Han, Shancheng Chen, Hai Ding, Guangquan Xu, Haitao Zhang
KEYWORDS:
Huaibei and Huainan Coalfields, Karst Water Disaster, Prevention and Control Technology, Dewatering and Depressurization, Grouting Reinforcement, Grouting and Sealing
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.14 No.4,
April
3,
2026
ABSTRACT: The karst water disasters pose a significant threat to the safe mining of the lower coal group in the Huaibei and Huainan Coalfields. Based on the karst hydrogeological characteristics, the classification of karst water disasters and the prevention and control technologies were studied. Results show that the floor of the lower coal group in the Huaibei and Huainan Coalfields comprises a sequence of karst aquifers, including (from top to bottom) the C3I, C3II, and C3III groups of the Taiyuan Formation and the Ordovician System (referred to as “C3I”, “C3II”, “C3III” and “O”, respectively). On the basis of the degree of hydraulic connectivity, water yield property, permeability, and drainability, the karst aquifer system beneath the lower coal group is divided into a three-layer structure: the C3I-C3II aquifer, the lower aquiclude of the Taiyuan Formation, and the C3III-O aquifer. Based on the differences in aquifer characteristics and water-filling type between the C3I-C3II and C3III-O aquifers, karst water disasters are classified into two types: direct water inrush from thin-bedded limestone (DT-type) and indirect water inrush from thick-bedded limestone (IT-type). Furthermore, due to the contrasting drainability of the C3I-C3II aquifer in the Huaibei and Huainan Coalfields, the DT-type is subdivided into the drainable type (D-type) and the undrainable type (U-type). For three types of karst water disasters, three typical prevention and control technologies are proposed: dewatering and depressurization of the aquifer (DDA), grouting reinforcement of the aquifer (GRA), and grouting and sealing of water-conducting channels (GSC). DDA is a direct approach applicable to the C3I-C3II aquifer in the Huainan Coalfield. GRA is also a direct approach, characterized by full coverage, and applicable to the C3I-C3II aquifer in the Huaibei Coalfield. GSC is an indirect approach, focused on detecting and sealing water-conducting channels, and applicable to the C3III-O aquifer in the Huaibei and Huainan Coalfields. The technologies described above are also applicable to other coalfields with similar geological and hydrogeological conditions in North China.