Water Resources Research Act Program

Details for Project ID 2011NJ281B

Release of Hazardous Metals into Surface and Groundwater by Microbial Oxidation of Sulfide Minerals

Institute: New Jersey
Year Established: 2011 Start Date: 2011-03-01 End Date: 2012-02-29
Total Federal Funds: $5,000 Total Non-Federal Funds: $10,001

Principal Investigators: Alexandra Walczak, Lily Young

Project Summary: Microorganisms can gain energy for growth by oxidizing reduced sulfide minerals. These sulfide minerals can serve as a sink for toxic trace metals such as arsenic, lead, cadmium, nickel, and mercury in ground and surface water. Through oxidation of the solid sulfide mineral, microorganisms can release and remobilize the associated metals into the aquatic ecosystem. This increased mobility of the metal ions can potentially serve as a non-point source for hazardous metals in surface and ground water. By determining the activities of these sulfide oxidizing microorganisms, their effect on metal mobilization can be monitored and assessed. Strain WAO isolated from the Lockatong formation based on its ability to oxidize the arsenic and sulfur in arsenopyrite will be used as a representative organism for this study. Initial studies show that this organism can also oxidize the sulfide in galena (PbS) and greenockite (CdS). We expect that a stoichiometric release of metal ions to sulfate production will be observed in this study. Additionally, microscopic analysis of the microbe-mineral interactions will show us the extent of colonization of the mineral by WAO. We anticipate that this study will elucidate the role of sulfide respiring organisms in the release of metals into ground and surface water, and allow for advanced modeling and mitigation strategies.