Iron-based abiotic destruction of chlorinated pesticides in groundwater

From July 1, 1995, to June 30, 1996, Prof. Eykholt and his graduate students, Doug Davenport, Greg Lowry, and Chris Sosnowski, evaluated the reactions of chlorinated herbicides with granular cast-iron metal. The central purpose was to screen one grade of iron with waters containing chlorinated solvents, pesticides, and herbicides to find evidence of reductive dechlorination reactions. If loss could be attributed to dechlorination, the effective reaction rates and rate kinetics would be determined. The original project goal was to perform batch and column tests with spiked site groundwater.

Reactive barrier technology has been applied to remove and contain chlorinated solvents, such as TCE, but there is evidence that other compounds, such as nitroaromatic compounds and the pesticide dichlorobromopentane (DCBP) can also be reduced upon contact with granular iron metal. Most of the reactions inferred are first-order with respect to the contaminant.

The goal of this report is to summarize the key findings of this Pesticide Research Project. Full detail of the literature review, experimental and analytical work has been reported within the M.S. Thesis of Mr. Doug Davenport (1996). This thesis has been submitted with this report, and electronic copies can also be obtained from Prof. Eykholt.

Davenport, Douglas T. (1996), Degradation and sorption of select triazine, analide, and carboxylic acid herbicides using zero-valent iron. M.S. Thesis, Civil and Environmental Engineering, University of Wisconsin – Madison