ERT技术在无机酸污染场地调查中的应用

Application of ERT Technology to Investigate Inorganic Polluted Sites

利用高密度电阻率法对硫酸废液污染的场地进行污染调查,由于硫酸废液侵入土壤,使其介质的溶质浓度发生了改变,导致SO42-与地表潜水作用,电传导性提高,被污染土壤含盐量增加,但是电阻率降低与未被硫酸废液侵入的土层形成了一定的电性差异.通过二维和三维电阻率层析成像(ERT)技术,圈定硫酸废液侵入土壤中的分布范围、侵蚀深度以及扩散羽流等,并对ERT结果进行土工试验异常验证.结果表明:硫酸废液污染土壤的视电阻率小于6.0Ω.m,污染区域长度达25.0m,深度约4.0m;地表土污染长度为12.0m,表面宽度约4.0m,污染土壤的总体积约为222.0m3.

High-density resistivity method was used to investigate a site contaminated by abandoned sulfuric acid. This method was based on the fact that, after abandoned sulfilric acid penetrates the soil, the change of medium concentration causes a reaction between SO4^2- and surface water, which results in increased electrical conductivity and soil salinity. These changes result in an electrical difference between contaminated and uncontaminated soil. The range of contaminated soil, the erosion depth and the spread of the plume were delineated by 2D or 3D electrical resistivity tomography （ERT） technology, and the anomalies were also verified. The results showed that the resistivity of soil contaminated by abandoned sulfuric acid was less than 6.0 Ω· m ; the plane of contaminated area was 25.0 m long and about 4.0 m deep; the contaminated surface soil was 12.0 m long and 4.0 m wide, and the volume of contaminated soil reached 222.0 m^3 .