Project ID: 2002AZ3B

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

Project Type: Research

Focus Categories: Toxic Substances, Hydrogeochemistry

Keywords: Arsenic, Bioconversion Metals, Sanitary Landfills, Mobilization, Toxic Substances, Residuals Disposal, Anaerobic, Leaching, Pollutants, Toxic Substances, Waste Disposal

Start Date: 03/01/2002

End Date: 02/28/2003

Federal Funds: $11,996

Non-Federal Matching Funds: $41,068

Congressional District: 5

Principal Investigators:
James Field
University of Arizona

A. Jay Gandolfi
University of Arizona

Abstract

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.

Progress/Completion Report PDF