Water Resources Research Act Program

Details for Project ID 2007ND146B

Analysis of Associated Bedrock-Aquifer System Sediments:Origins of Electron Donor-Rich Aquifers in Eastern North Dakota

Institute: North Dakota
Year Established: 2007 Start Date: 2007-03-01 End Date: 2008-02-29
Total Federal Funds: $9,600 Total Non-Federal Funds: $19,200

Principal Investigators: Scott Korom

Abstract: Nitrate pollution has long been recognized as the most prevalent form of groundwater pollution. The only effective process to remediate nitrate contaminants is denitrification, typically through natural attenuation. This process reduces nitrate (NO3-) to harmless nitrogen gas. The process occurs naturally, requiring only an oxygen-limited environment, the presence of nitrogen digesting bacteria, and the availability of electron donors. The three most common electron donors are organic carbon, sulfide (typically as pyrite, FeS2), and ferrous iron minerals. Research has also shown that the controlling factor in this reaction has typically been the availability of suitable electron donors within the aquifer sediments. The objective of this research is to establish a link between the denitrification capacity of North Dakota aquifers with the electron donor composition of the surrounding bedrock, including pyrite, organic carbon, and ferrous iron. Once this relationship is more clearly defined, a qualitative index (low, medium, and high) of aquifer denitrification capacity may be developed, based on the probable source of parent material. This index could then be used to focus, in a cost-effective fashion, more extensive and expensive geochemical analysis on specific aquifers or zones in specific aquifers.