The United Soybean Board (USB) is funding research with North Carolina State University (NCSU) to evaluate a method for treating nitrate-impacted groundwater with soybean oil.

Groundwater in large communities has become enriched with nitrate nitrogen from a variety of sources, including chemical fertilizer application as well as human and animal wastes.

A surface barrier will be installed to stimulate biological denitrification by injecting a soybean oil-in-water emulsion through wells installed perpendicular to groundwater flow. As water moves through the barrier, a small portion of the emulsified soybean oil will dissolve, stimulating nitrogen reduction.

Groundwater monitor wells, installed up- and down-gradient of the barrier, will track nitrate removal before groundwater is discharged to the surface.

“Pressure from regulators on animal waste operators to clean up nitrate-contaminated groundwater is growing,” says Robert Borden, primary researcher on the project. “If the soybean oil barriers are successful and remain cost-competitive, regulators are much more likely to require clean up of these sites.”