TECHNOLOGICAL RESEARCH ON SAFETY EVALUATION OF PUMPING WELL APPROACHING TO HIGH CONFINED AQUIFER IN NORTH CHINA— A CASE STUDY OF XUECUN COALMINE IN FENGFENG MINING AREA
Abstract：Lack of suitable norms or codes to observe made it difficult for scholars to evaluate hydrogeological conditions for safe advance of the pumping well approaching to high confined aquifer in Xuecun coal mine，Fengfeng mining area，the heavy water mining area. To solve the problem，the authors take advantage of pressure-tunnel model，key stratum theory，the relationship of permeability vs. strain and numerical simulation methods to evaluate the safety of pumping well approaching to the strong Ordovician limestone aquifers based on hydrogeological condition analyses. The same conclusions from all the above methods were drawn that the failure area is far away from the strong aquifer and the advancing engineering is safe. The authors considered that water inrush coefficients of floor strata given by the regulations were not suitable for pumping well in hydrogeological evaluation. Water inrush would not take place during the well advancing even though the inrush coefficient excesses the limit given by the regulations. The methodology given in the paper explored a way for pumping well safety evaluation in hydrogeology for North China typed coal mines.
