In-Situ Remediation of Chlorinated Solvents using Zero Valent Iron and Clay Mixtures: A Case History

This paper presents the results of a case history involving the use of the zero valent iron and clay (ZVI-Clay) technology for remediation of chlorinated solvents at a DuPont plant located in Martinsville, Virginia. The ZVI-Clay technology is an in-situ approach to chlorinated solvent remediation that involves addition, via soil mixing, of a stabilizing agent (i.e., kaolin clay) and zero valent iron directly into the source zone. The result is two-fold: decreased mobility of contaminants and degradation of chlorinated solvents via reaction with the zero valent iron. Application of the ZVI-Clay technology to a site in Martinsville, Virginia, contaminated primarily with carbon tetrachloride has resulted in greater than 99% degradation of all chlorinated compounds, including by-products. In addition to describing this case history, current and future research efforts aimed at further developing the technology are described briefly.