Groundwater Vulnerability Assessment In Hexi Area Of Nanchong Chemical Industrial Park

In view of the fact that the problem of groundwater pollution caused by accelerated industrialization and population growth has become a key factor restricting sustainable development,this paper takes the Hexi area of Nanchong Chemical Industrial Park in Sichuan as an example to identify the regional groundwater vulnerability and then plan.Groundwater vulnerability zoning,in order to provide technical support for the management departments of Sichuan Nanchong Chemical Industrial Park to guide enterprises to improve groundwater environmental protection measures,is of great significance for the protection of groundwater environment in China.1.Based on the concept of groundwater vulnerability and groundwater vulnerability assessment at home and abroad,combined with the actual situation of the study area,the paper analyzes the regional natural geography,meteorological hydrology,geological conditions and human activities.Based on the traditional DRASTIC model evaluation factor,the evaluation factors affected by human activities,namely the status of land use and the degree of groundwater exploitation,were added to establish an optimized and improved DRASTIC model.Groundwater vulnerability assessment was carried out by combining ArcGIS and groundwater vulnerability assessment models.2.The paper uses the traditional DRASTIC model index weight determination method and the principal component-factor analysis method,correlation analysis method and analytic hierarchy process to determine the weight of the evaluation index,and forms two evaluation methods.The evaluation results are consistent: the evaluation results indicate that the river terraces are The Quaternary areas are highly vulnerable,and the fragility of other areas is relatively low,showing a certain regularity.The groundwater vulnerability is gradually weakened from the west to the eastern Jialing River.3.According to the distribution of water quality over-punctuation points in the sampling points,the two evaluation results are tested.The test shows that the two evaluation sub-graphs basically meet the test criteria of the test area’s vulnerability and the water quality of the sampling points in the area.It was found that the improved DRASTIC model has a better effect on the groundwater vulnerability assessment than the traditional DRASTIC model,which can reflect the integrity of the groundwater system and reduce the influence of human subjective judgment,making the weight value more reasonable.At the end of the paper,based on the evaluation results,it is suggested that when a groundwater infiltration risk facility is built in a highly vulnerable area,anti-seepage measures must be taken.If necessary,the anti-seepage level should be increased to minimize the environmental risk accident of pollutant leakage.