Simulation Study On The Migration Of Ammonia Nitrogen In The Underground Water In Coastal Area Of Fengnan In Tangshan City

Emissions of ammonia nitrogen far beyond the environmental capacity of the receiving water has become one of the most important problems in water ecological environment protection in our country, there are serious pollution phenomenon of ammonia nitrogen in the research area of Fengnan coastal areas in Tangshan City.It is a good indicator to reflect the early pollution of groundwater that the change of ammonia nitrogen concentration. One is because ammonia nitrogen is easy to soluble in water, it will prior to other pollutants reflected in indicators of water quality when the groundwater is pollutioned; On the other hand is that the ammonia nitrogen pollutants exist widely in groundwater. Therefore,through the study of ammonia nitrogen pollution of groundwater and puts forward some effective measures of prevention is one of the environmental problems to be solved in current witch.Groundwater is an important drinking water source in Fengnan coastal area of Tangshan City. In recent years, with the development of economy and urbanization process speeding up, the environmental problems caused by the discharge of “three wastes”increasingly, through the investigation of 9 shallow wells in Fengnan coastal area of Tangshan City, and 6 wells of ammonia nitrogen exceed the standard which the exceed the standard ratio of 1.71 ~ 5.83, shallow groundwater nitrogen pollution in the study area is more serious.Tangshan City has emerged signs of groundwater pollution,due to groundwater contamination undetected and is difficult to control and recovery, so early detection is the best way to avoid groundwater pollution.Based on the field survey of the study area, by the research of the hydrogeological conditions, recharge conditions, aquifer types, and at the same time,through pumping test and seepage test to obtain hydrogeological parameters of this area respectively in the field, summarize the aquifer in the study area,and use of Visual Modflow software to establish the groundwater flow and solute transport numerical model, research on the phreatic nitrogen migration rule, the results of the study show that the phreatic aquifer groundwater of Quaternary in study area flow mainly from north to south and the coefficient of the aquifer permeability is small, the migration of the ammonia nitrogen in the water move from north to south, because the study area of shallow aquifer hydraulic gradient is relatively small, so the migration of ammonia nitrogen with the water flow is slow, and the migration process is not easy diffusion. It has important theoretical and practical significance of this topic research for the prevention and control of ammonia nitrogen pollution of the underground water in Fengnan coastal zone of Tangshan City.