Ethanol‐Stimulated Bioremediation of Nitrate‐Contaminated Ground Water

Abstract

Abstract Extensive characterization of a nitrate‐contaminated site at a Canadian airport revealed that natural attenuation of the plume was limited due to aerobic conditions. However, nitrate removal rates as high as 1.4 mg‐N/(L/day) were observed in batch tests carried out under denitrifying conditions with an added carbon source. On the basis of these results, a field denitrification pilot test using a setup of vertical withdrawal and injection wells was carried out. Ethanol was used as a carbon source to stimulate the growth and activity of indigenous denitrifying bacterial populations. Denitrification rates of up to 1.2 mg‐N/(L/day) were achieved during the test. The test confirmed the feasibility of the technology, which uses the indigenous bacterial populations for denitrification and transforms the aquifer into a subsurface bioreactor.