The Analysis Of Water Quality Evaluation Regular Pattern And The Pollution Trend Prediction Of Groundwater In Dawu Well Field, Zibo City

Zibo city of Shandong province takes groundwater as the main soiree of watersupply. Due to the historical reasons Qilu Petrochemical Corporation and many otherlarge chemical enterprises are located in the叩stream of Dawu well ifeld，petroleumproducts are easily leaked out dicing the process of production, storage andtransportation, the oil organic pollutants that leaked into imderground will occur aseries of physical, chemical, and biological reactions water source in soil environmentand cause serious pollutions to the groundwater environmental system. Zibo Dawuwell ifeld can be said to be the epitome of petrochemical works, oil leakage and otherpetroleum contaminated sites, and the pollution characteristics is very typical due toits location in karst ifssure region. So the analysis of water quality evaluation regularpattern and the pollution trend prediction of ground water are very important. Also theresearch could be help ifll to groundwater management and protection in the area.In this study, by researching on the changes of groundwater quality in Dawu areaevery year, study on water quality evaluation regular pattern in the area, and build thenumerical simulation model，using quantitative description about the oil pollutants inthe migration rule, in order to predict the trend of petroleum pollution in thegroundwater.In this paper the main research results are as follows:（1）Researches show that before ethylene new district set up and20years afterthat, great changes have taken place to groundwater type in Dawu area. The entiregroundwater chemical types built by HCO₃-Ca-Mg type before the district built,andgradually transformed into coexistence state of HCO₃-Cl-Ca-Mg and SO₄-C1-Ca-Mgatfer set up20years later. Ca，Mg have been little increased when the naturalbackground value is higher，CI showed a sharp irse，so that it inferred Dawu area hasbeen inlfuenced by ethylene district leakage pollution, and the pollution is increasedyear by year.（2）Researches have shown that although the concentration of Dawu groundwaterorganic pollutants are individual annual decline in recent years, but it’s a rising trendon the whole. Combined with the monitoring points, oil pollutants in the groundwater is higher in the west and lower in the east has been analyzed out.The highest pollutantconcentration monitoring point is located in ethylene new district, and the pollutantconcentration in ethylene new district premises generally higher than the outside offactory,so it infers that oil pollutants leakage in ethylene new district is the mainpollution soiree of the research area.（3） Based on the simulation of benzene, chloroform and carbon tetrachloride,found that all of these three leaked pollutants will enter into the Dawu well fieldconcentrated water period in ethylene district atfer transported40years later. Theresults also showed that the formed pollutants from benzene in the process oftransport are bigger than the pollutions formed rfom chloroform and carbontetrachloride,that means the excessive area of benzene is greater than the excessivearea of chloroform and carbon tetrachloride, the result is also matched with the actualwater quality situation from monitoirng points in2009.