Replace Heterotrophic with Hydrogenotrophic Denitrification System to Solve Nitrate Contamination in Long Island, New York

Nitrate contamination is currently the greatest threat to groundwater on Long Island, New York - the one and only source of drinking water for the residents. The maximum allowed nitrogen contaminant concentration in a bottle of water is 10 mg/L, but groundwater in some areas of the island now reaches the level of 30 mg/L. Long exposure to nitrate will cause gastric cancer, methemoglobinemia in infants (blue baby disease), sclerosis and decreased functioning of the thyroid gland. New York legislators aim to replace poor household cesspools and septic systems with I/A OWTS technology to prevent untreated wastewater from leaking and heading to groundwater underneath. However, we considered the solution to be costly yet ineffective. Here we hypothesize to replace the heterotrophic denitrification component in I/A OWTS with a cheaper yet effective hydrogenotrophic denitrification component for septic systems in less affected areas. The new system utilizes hydrogen, an inexpensive and common gas, to be pumped into the tank by a reactor. Dissolved hydrogen ions serve as electron donors that participate in a redox reaction with nitrate ions to cancel the negative charge, converting nitrate into nitrogen gas and releasing it into the atmosphere with no production of secondary pollutants. We anticipate our research to be the building block for further investigation in applying this technology to modern septic systems.

Project Mentor: Annette Hilton

Faculty Advisor: Scott Jasechko