The Influence of pH on Subsurface Denitrification Stimulated with Emulsified Vegetable Oil

Treatment of nitrate rich groundwater using permeable reactive barriers (PRBs) established with injection emulsified vegetable oil is receiving attention in areas where discharges contribute to eutrophication (e.g., Cape Cod, MA). To better understand the biogeochemical process kinetics when (EVO) used stimulate denitrification within subsurface, microcosm experiments and process-based modeling were conducted for pH conditions ranging from 4 8. Biomass variability soil variations found affect denitrification, limited reduction observed below 5.0. Different rates associated biomass suggest that a greater characterization indigenous biological community may improve PRB design operation. Process-based employed activated sludge model No 3 (AMS3) framework assumes as two-step anoxic dependent primarily on heterotrophic bacteria, soluble substrate, nitrate, nitrite. Experimental data calibrate under neutral low pH, resulting robust set equations can be coupled transport future research effectiveness.