Research Of Migration Law Of Poisonous Meta In Soil In Sewage Irrigation Area

Sewage irrigation is using domestic sewage and industrial wastewater by harmless treatment for farmland irrigation,gardens irrigation,groundwater reservoir recharge directly of indirectly.Because of kinds of contaminating material, using the sewagewater for irrigation has caused the deterioration of soil environment. How to understanding the siol harm caused by sewage, It’s a question needed solve quickly.The research is based on "Groundwater pollution evalution in North China Plain", taking Xiao River sewage area in luancheng that the Shijiazhuang urban sewage flowing through. Research a profile perpendicular to Xiao River, drilling15groundwater monitoring wells,sampling137soil samples and28groundwater samples.Research the migration law and distribution characteristics of poisonous metals arsenic,chromium,cadmium,lead and mercury in soil and groundwater, throughing soil and groundwater samples, investigating lithologic structure, and the influnce of poisonous metals in sewage to soil groundwater and riverbed-soil.Main conclusions are as follows:(1) Lithology has an effect on the enrichment of poisonous metals in soil. Metals migrate fast in silty soil and silty clay, but migrate slow in sand.(2) Different metals have different vertical migration law. Accoding to the test data of poisonous metals in soil, the migration ability from weak to strong are Cr, Pb, Hg, Cd, As.(3) The river seepage has some influence on the distribution of poisonous metals. Poisonous metals enrich in the soil near the river. A preliminary analysis on the range of influence is150meters.(4) Poisonous metals in sewage enrich in riverbed-soil mostly, and the content of poisonous metals in the soil which buried deep less than3m is severe than the deeper soil by sewage irrigation. The content of poisonous metals are low in groundwater.