Water Resources Research Act Program

Details for Project ID 2002AZ3B

Microbial Mediated Mobilization of Arsenic from Drinking Water Treatment Residuals in Landfills

Institute: Arizona
Year Established: 2002 Start Date: 2002-03-01 End Date: 2003-02-28
Total Federal Funds: $11,996 Total Non-Federal Funds: $41,068

Principal Investigators: James Field, A. Gandolfi

Project Summary: The ultimate goal is to obtain the scientific knowledge required to assess the suitability of non-hazardous landfilling as a safe method for the disposal of As residuals. The study results will indicate the likelihood of the microbial mediated mobilization of arsenate adsorbed onto drinking water treatment residuals and disposed into landfills. Microbial mediated mobilization is expected to result from the direct bioconversion of arsenate via reduction/methylation to arsenite and arsine and their methylated counterparts. Or microbial mediated mobilization can result from indirect dissolution of the residual adsorbant (ferrihydrite), releasing adsorbed arsenate. The insights gained will be used to design an appropriate protocol for estimating the hazard of As residuals in landfills (to replace the currently inadequate Toxicity Characteristic Leaching Procedure). Additionally, the research results will aid in the development of strategies and guidelines for the safe disposal of As residuals in landfills. For example guidelines recommending disposal of As residuals in landfills free of (or low in) organic wastes may be required.