Risk Assessment on Groudwater Contamination Accompanying with Soil Adsorption

根据以下研究完成了研究项目；(1)土壤颗粒、孔隙结构和吸附能力。(2)各污染物的吸附特性；(3)环境风险评价的质量控制。第一项活动给出结论；(1)土壤吸附与含水饱和度无关，呈恒定值，而分散性随含水饱和度的降低而增加。(2)提出了一种利用注入空气的透气性试验估算砂土孔隙大小的新方法。第二项活动的结果是；(1)溶质组分的分布系数随其他共存组分浓度的增加而减小；(2)竞争吸附模型表明，少量污染物的吸附不会改变本底组分的吸附特性，但少量污染物的吸附在本底组分吸附后有所减少。三是通过水槽模型的水量估算和土壤隔室模型的水质估算。模拟结果表明，土壤吸附和生物反应等相关参数对土壤中肥料的迁移具有重要影响，可用于环境风险评价。

Research projects were accomplishied according to the following studies ; (1) Soil Particle, Pore Structure and Adsorption Capacity. (2) Adsorption Characteristics of Each Contaminants, and (3) Quality control for Environmental Risk Assessment.The first activity gave the conclusions ; (1) Soil adsorption took a constant value independent on water saturation, on the other hand, dispersibility increased with decreasing water saturation. (2) A new method was proposed to estimate the pore size of sand using an air permeability test with air injection.The results of the second activity were that ; (1) Distribution coefficient for a solute components took a small value with increasing the concentration of the other coexisting components, and (2) Modeling of competitive adsorption indicates that no change took place in adsorption characteristics of background components due to a small amount of contaminants adsorption, however, a small amount of contaminants adsorption decreased after background components adsorption.The third was performed by water quantity estimation of tank model and water quality of soil compartment model. The simulation results showed that the parameter relating to soil adsorption and biological reaction play an important role on transport of fertilizer for the environmental risk assessment.