Water Resources Research Act Program

Details for Project ID 2013ND273B

Electron Donor Contributions to Denitrification in the Elk Valley Aquifer, ND

Institute: North Dakota
Year Established: 2013 Start Date: 2013-03-01 End Date: 2014-02-28
Total Federal Funds: $4,811 Total Non-Federal Funds: $14,789

Principal Investigators: Scott Korom

Abstract: Denitrification, the conversion of nitrate to nitrogen gas (N2), can remove nitrate from groundwater.The four general requirements for denitrification are: (1) the presence of N oxides (NO3-, NO2-, NO, and N2O) as terminal electron acceptors, (2) the presence of bacteria possessing the metabolic capacity, (3) suitable electron donors, and (4) anaerobic conditions or restricted O2 ability. The most important requirement for denitrification in aquifers is the presence of suitable electron donors. The three types of electron (e-) donors that contribute to aquifer denitrification are organic carbon, pyrite (FeS2), and ferrous iron minerals. These e- donors are relatively abundant in aquifer sediments in eastern ND. The objective of the proposed research is to study the geochemical evolution of the groundwater in the Elk Valley Aquifer in-situ mesocosm (EVA ISM) during denitrification tracer tests to determine the contributions of e- donors to the denitrification.Is there a cycling among the e- donors and the bacteria that cause denitrification? This research will be the first to study the variation in the contributions of e- donors in aquifer sediments for such a long period of time, nearly eight years. This will be yet another step in predicting aquifer denitrification parameters based on the e- donors present in aquifer sediment. Furthermore, this research will provide insights into which type of e- donor causes the greatest aquifer denitrification rates.