The numerical simulation for coal gangue as roadbed material on groundwater nitrate concentration

Abstract

Numerical simulation was used to elaborate temporal and spatial distribution of nitrate concentration in groundwater under one highway,which was constructed with coal gangue based on experiment.Experimental results indicated that the contaminated area spread around over time,but more obviously in horizontal direction,especially in groundwater flow direction.In addition,nitrate concentration decreased gradually in two-axis direction,and contaminated degree decreased with the increasing of distance from the contaminated source caused leaching solution.Numerical simulation suggests that the nitrate concentration (N) in the section will only meet the standard of class III (GB/T14848-93) for groundwater environmental quality after 10 years,although the concentration reaches the standard of class I currently