摘要
Excessive groundwater withdrawal from the Ordovician karstified limestone aquifer near the city of Xingtai in China has created many cones of depression in piezometric levels of the groundwater (>100 m of drawdown), potentially affecting groundwater-dependent environments and threatening urban water supplies. Groundwater investigations and numerical modeling were undertaken to determine the factors that have caused groundwater depletion in the region so that groundwater protection measures could be developed and implemented. These investigations found the major cause of groundwater depletion was water drainage from iron ore mines in the region which had the largest effect on piezometric levels in the aquifer. Based on the integrated study, comprehensive methods of controlling depletion are proposed and tested successfully for groundwater protection in the region. These methods mainly include: outcrop recharging the aquifer; optimization in usage and allocation of water resources regionally; the use of curtain grouting in iron ore mines to reduce drainage of the aquifer; and drainage control in mining operations. Applying these methods, piezometric levels in the aquifer have increased by more than 30 m and previously dry springs are now flowing on a seasonal basis.