Design Methodology of Granular Iron Content to CVOCs Contaminated Ground in Consideration of Mixture Heterogeneity and Field Application
Keijiro ITO, Junichi KAWAVATA and Masashi KAMON
Abstract:Remediation method using zero-valent granular iron is one of the most popular in-situ remediation technologies, and is designed to eliminate contaminant migration beyond the boundaries of the contaminated site by constructing a Permeable Reactive Barrier (PRB) using an iron sand mixture. In contrast, direct in-situ mixing of zero-valent iron with the actual contaminated soil using a higher mixing ratio has been proposed to effectively clean up in a short period of time. For this direct mixing method a proper design methodology should be devised. To propose this design methodology, we conducted a batch test, a column test, a three-dimension advection-dispersion-attenuation analysis, and a field test. The results were as follows. The design based on a batch test was confirmed that it coincided with a column test and the clean-up result in a field test. The safety factor of a granular iron mixture ratio was evaluated from the numerical analysis, in which the heterogeneity of granular iron mixture was taken into consideration. Example of evaluating the heterogeneity of granular iron mixture was shown in the field test. Key Words:Remediation method, Granular iron, Contaminated ground, Field application, Numerical analysis