Study On The Pollution And Migration Of Volatile Halogenated Hydrocarbons In Groundwater In A Chemical Plant

The problem of groundwater pollution by volatile halogenated hydrocarbons has been very serious all over the world.In many cities in northern China,groundwater pollution is found in the groundwater pollution investigation,which is a great threat to people's life and health.Distribution in the aquifer space of volatile halogenated hydrocarbons,and underground water flow field and aquifer structure are closely related,once entered into the aquifer,want to go out when it is difficult in the short time,and the organic matter with time and diffusion in groundwater,the adjacent groundwater aquifer pose a huge threat.Therefore,it is significant to study the scope of pollution,the cause of pollution and the way of pollution.In this paper,a typical contaminated site as an example,with comprehensive analysis,evaluation of groundwater pollution and pollution of halogenated hydrocarbons migration analysis method,the carbon tetrachloride as the research object,research and analysis of groundwater flow field evolution trend of carbon tetrachloride source,migration and spatial distribution.It provides a theoretical basis for groundwater pollution management and groundwater remediation of small chemical plants in the next research area.The main research results of this paper are as follows:(1)the main lithology of the inner layer of the region is the Quaternary and the Taishan rock group,the groundwater flow is generally from the northeast to the southwest,the southern topography is relatively low,the only way for surface water and groundwater discharge.(2)in the research area of chemical plants sampled in 2016 monitoring results show that the organic pollution of groundwater is very serious with carbon tetrachloride,trichloroethylene,1,1,2-three and 1,2-two chloroethane chloride,carbon tetrachloride and exceed the standard time of maximum,near the small chemical plant due to serious pollution of groundwater volatile halogenated hydrocarbons.(3)by the supply of fissure water on both sides of the mountain,the carbon tetrachloride pollution range is mainly distributed in the valley area,the scope of the dispersion is not large,and the pollution degree of the main runoff zone is high.The range of over standard pollution of carbon tetrachloride is about 73225.9m2,and the shape of the pollution plume is approximately elliptical.The distribution of pollution concentration in space is generally low in the southwest direction and high in the northeast.The most polluted well point was also transferred from the well JD003 point in 2014 to the well No.49 in the year of 2016,which moved about 585 m.(4)the study area groundwater pollution by volatile halogenated hydrocarbons is increasing with time,pollution,volatile halogenated hydrocarbons in groundwater will develop to the small chemical plant in southwest and South direction.Due to the density of volatile halogenated hydrocarbons are larger than the water,the vertical direction of gravity,the aquifer from top to bottom,the concentration of organic pollutants gradually increased.(5)from the organic pollutants monitoring data of the monitoring points near the study area,although the content of organic pollutants in 2016 compared to 2014 the same wells has been reduced,but its concentration is much higher than the national standard limit,the safety of drinking water for the surrounding residents still constitute a great threat.