Deep Groundwater Flow Patterns Induced by Mine Water Injection Activity

Ge Chen; Zhimin Xu; Dmytro Rudakov; Yajun Sun; Xin Li

doi:10.3390/ijerph192315438

Deep Groundwater Flow Patterns Induced by Mine Water Injection Activity

Int J Environ Res Public Health. 2022 Nov 22;19(23):15438. doi: 10.3390/ijerph192315438.

Authors

Ge Chen¹, Zhimin Xu¹, Dmytro Rudakov², Yajun Sun¹, Xin Li¹

Affiliations

¹ School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China.
² Department of Hydrogeology and Engineering Geology, Dnipro University of Technology, av. Dmytra Yavornytskoho, 19, 49005 Dnipro, Ukraine.

Abstract

Mine water injection into deep formations is one of the effective approaches for reducing the drainage from coal mines in the arid and semi-arid region of the Ordos basin, China. Many coal mines are attempting to execute the related projects. Under the influence of groundwater protection, the understanding of regional groundwater flow is becoming highly important to the mine water monitoring, whereas quite few academic research teams focus on the deep groundwater flow pattern by mine water injection. This paper reveals the spatial distribution of Liujiagou Formation that is in positive correlation with the terrain, and its local thickness is influenced by the dominant W-E and NE-SW directions of geological structures. Only a part of sandstone rocks consists of aquifers, the rest 61.9% of relatively dry rock provide the enhanced storage space and partial mudstone aquicludes decrease the possibility of the vertical leakage for mine water. The dynamic storage capacity is evaluated at 2.36 Mm³ per 1 km² and over 25.10 billion m³ in this study area. Two hydrogeologic cross-sections of basin-scale identify the W-E and N-S regional groundwater flow directions, with the lower Yellow River catchment becoming the discharged region. The hierarchically and steadily nested flow systems containing coal mining claims are influenced by coal mining activity. The groundwater depression cone in a shallow coal measure aquifer is caused by mine water drainage whereas the groundwater mound in Liujiagou Formation is generated by mine water injection activity. The numerical simulation revealed that the groundwater head rebound is slightly decreased and will not recover to its initial baseline within 500 years due to its low porosity and permeability. This study elucidates the deep groundwater flow patterns induced by mine water injection and provides a practical methodology for the management and pollution monitoring of mine water injection activity.

Keywords: Liujiagou Formation; deep groundwater flow; mine water injection; storage capacity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Coal / analysis
Coal Mining*
Environmental Monitoring / methods
Groundwater* / chemistry
Water
Water Pollutants, Chemical* / analysis

Substances

Water
Coal
Water Pollutants, Chemical

Grants and funding

This work was funded by the National Key Research and Development Project of China, grant number 2019YFC1805400; the Fundamental Research Funds for the Central Universities, grant number 2022QN1061; the Natural Science Foundation of Jiangsu Province, grant number BK20210524, and National Natural Science Foundation of China, grant number 42202268.