Water Resources Research Act Program

Details for Project ID 2014TN105B

Underground Reactive Barrier to Attenuate Contaminants from Agricultural Drainage

Institute: Tennessee
Year Established: 2014 Start Date: 2014-03-01 End Date: 2016-02-28
Total Federal Funds: $10,000 Total Non-Federal Funds: $20,000

Principal Investigators: Jaehoon Lee, John Buchanan, Jennifer DeBruyn, Shawn Hawkins, Andrea Ludwig, Forbes Walker

Abstract: There is a great need for cost-effective and proven best management practices to mediate contaminants (e.g. excess nutrients, pathogens, veterinary pharmaceuticals, etc.) in agricultural drainage. One technology for remediating agricultural chemicals, such as nitrogen (N), is promoting denitrification using denitrification beds, also called underground reactive barriers. A denitrification bed is constructed by mixing an organic carbon (C) source (typically sawdust or woodchips) into soil below water table in order to intercept groundwater flow. The increased and continued supply of C to denitrifiers enhances denitrification of the water, thus reduced NO3- in the discharge. The purpose of this proposal is to carry out field studies evaluating an advanced underground reactive barrier using combination of woodchips and charcoal/biochar. Our preliminary study showed that addition of biochar/charcoal was very effective to remove P as well as veterinary antibiotics which are emerging contaminants. We propose to install underground reactive barriers in the new UT Little River Animal and Environmental Unit located in Walland, TN. The research and education center is bounded by streams on three sides and lies in the floodplain of a state-declared exceptional waterway. This is a unique opportunity, because the data from this study will enable us to advance the underground reactive barrier technology to treat various contaminants in agricultural drainage while utilizing byproducts from bio-energy production. We will determine if these barriers will help to reduce N, P, veterinary antibiotics as well as pathogen/fecal bacteria.