Elemental mercury has a very high volatility allowing easy dissipation from water or soil into air. To better understand how the kinetics of diffusion of elemental mercury through a medium, which is soil in this study, a mercury diffusion column experiment was done. The correlation between temperature and equilibrium concentrations of mercury in standardized soil samples and a pure mercury standard were determined. Total mercury concentrations were analysed using CVAFS. The effect of time and soil depth to the kinetics of mercury diffusion were determined. Differences in mercury concentrations at different sampling probes were observed during the first few gas phase analyses. Equilibrium was reached through the column after 72 hours.
Laboratory analytical results of 22 sets of hydrophobic adsorbent coils containing surface soil-vapor and two soil samples collected by conventional intrusive method from each boring location at two active dry cleaning facilities in the State of Illinois, U.S.A, were presented to evaluate the performance of soil-vapor survey. The most critical factor to determine the effectiveness of soil-vapor survey is the distance from the soil-vapor sampling device to the actual contamination, which is a function of soil porosity, permeability, primary lithology, and other geological and hydrogeological site-specific parameters. Also this factor can be affected by the history of contaminant-generating operations. The laboratory analytical results in this study showed longer drycleaning operation history (i.e., 50 years) and presence of fine sand at the beneath Site B allow the contaminants to migrate farther and deeper over a fixed time compared to Site A(i.e., 35 years and silty clay) so that the soil-vapor survey is not likely the most effective environmental site investigation method alone for Site B. However, for Site A, the soil-vapor survey successfully screened the site to identify the location reporting the highest soil concentration of chlorinated solvents.
본 연구는 토양 및 지하수 오염의 정화방법으로써 토양증기 추출법을 이용할 경우, 이의 효율적 운용을 위하여 추출공 주변에 차단벽을 설치할 경우, 추출펌프유량의 크기 및 펌프가동의 형태 등이 제거효율에 미치는 영향을 평가하기 위하여 수치해석을 이용하여 검토하였다. 그 결과 추출공 주위에 차단벽을 설치할 경우 및 추출펌프의 운용을 단속적으로 실시하였을 경우, 추출공 주변에 고농도의 가스분포를 밀집시킴으로 인해 고농도의 가스를 제거할 수 있게 되어 제거율이