TY  - JOUR
AU  - Humphrey, Charles 
AU  - Pradhan, Sushama 
AU  - Bean, Eban 
AU  - O’Driscoll, Michael 
AU  - Iverson, Guy 
PY  - 2015
TI  - Preliminary Evaluation of a Permeable Reactive Barrier for Reducing Groundwater Nitrate Transport from a Large Onsite Wastewater System
JF  - American Journal of Environmental Sciences
VL  - 11
IS  - 4
DO  - 10.3844/ajessp.2015.216.226
UR  - https://thescipub.com/abstract/ajessp.2015.216.226
AB  - A permeable reactive barrier was installed between a large Onsite Wastewater System (OWS) and a monitoring well located down-gradient from the OWS. Groundwater samples from the well had shown elevated and increasing concentrations of NO3--N (>20 mg L-1 for 2 years). The barrier was constructed using woodchips from various tree species that were placed in a trench excavated to approximately the same depth as the well which was experiencing elevated NO3--N concentrations. Groundwater samples (5) were collected from the well between two weeks and four months after the barrier was installed. Groundwater NO3--N concentrations dropped by an average of 5 mg L-1, while Dissolved Organic Carbon (DOC) concentrations increased by 11 mg L-1 and Cl concentrations stayed relatively stable (<2 mg L-1 increase). The data suggest that denitrification fueled by the DOC from the barrier may be contributing to the lower NO3--N concentrations. Monitoring will continue at the site to determine the longer-term water quality trends. More research should be conducted to evaluate the applicability of permeable barriers as a best management practice for non-point sources of pollution in nutrient sensitive areas.