Numerical Simulation Of The Trnsport Of Chemical Pollutants In Groundwater Enviroment

In recent years,hazardous chemical leakage accidents occur frequently,which often lead to the spread of dangerous chemicals into the soil or groundwater environment due to untimely disposal or excessive leakage.This will cause potential harm to the people's life and drinking water safety in the vicinity of the leak area.At present,the prediction of solute diffusion in soil and groundwater environment mainly depends on numerical simulation.In order to predict the distance and range of hazardous chemical transport and diffusion in a certain period of time,it is necessary to establish a model according to the field situation and analyze the pollutant diffusion.This method usually has some limitations.This is because the actual hydrological and geological conditions are usually very complex.Modeling work often requires a large number of researches and analysis of relevant data,and it takes a long time also to be inefficient.It is difficult to provide timely help for short-term treatment after the accident.In this paper,the environment below the surface is divided into unsaturated and saturated conditions.Solute transport under different geological,hydrological and meteorological conditions is simulated by HYDRUS and GMS.The experiment of solute diffusion in unsaturated soil and the experiment of solute diffusion in saturated soil were carried out at first.Comparing the experimental results with the simulation results,the relative error was found to be within 10%,which verified the reliability of the model used in the simulation.In this paper,HYDRUS and GMS are used to simulate the steady rainfall,fixed head boundary,and other solute transport processes in unsaturated and saturated environments,respectively.Five critical time points for solute diffusion are defined.According to these five time points,the solute diffusion law is obtained,and the above time nodes are fitted to the solute migration and diffusion conditions.In this paper,HYDRUS and GMS are used to simulate solute transport processes in the steady rainfall,fixed head boundary,and other conditions in unsaturated and saturated environments.Five critical time points for solute diffusion are defined.According to these five time points,the solute diffusion law is obtained,and the five time points are fitted to the solute migration and diffusion conditions.When the hydrological,geological and meteorological environmental conditions of pollutant diffusion meet the conditions in this paper,the basic conditions of solute diffusion can be obtained directly from the above environmental parameters.It is convenient for the personnel concerned to respond quickly and formulate the emergency plan to minimize the damage to the environment caused by the accident as much as possible.