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Removal of Nitrate from Ground Water using Metals Objective & Scope 1. Gain mechanistic insight into the reduction of nitrate by metal Main Contents Nitrate is a common groundwater contaminant in the United States. Anthropogenic sources such as nitrogen fertilizers, animal wastes, and septic systems account for most nitrate contamination of groundwater. Irrigation and storm runoffs from farmlands often carry high levels of nitrate, which eventually reaches the groundwater. Nitrate itself is relatively non-toxic; however, it can be microbially reduced to nitrite, which poses several health threats to humans including methemoglobinemia, liver damage, and cancers. Nitrite causes methemoglobinemia by oxidized (Fe3+) hemoglobin, called methemoglobin, is incapable of binding oxygen. For a number of reasons, methemoglobinemia occures mostly in infants and is also known as "blue-baby syndrome". Current technologies to remove nitrate from water include ion exchange, reverse osmosis, biological denitrification, and chemical reduction. Reverse osmosis and ion exchange are not selective for nitrate and requires frequent regeneration of the media. Both processes do not destroy nitrate and generate secondary brine wastes. Biological cenitrification is unfavorable because it requires intensive maintenance and constant supply of organic substrates. Additional drawdacks include biomass sludge disposal and treatment (areation and disinfection) of denitrified water. Moreover, these microbial processes are generally slow and sometimes incomplete compared to chemical reduction. This study has been undertaken to evaluate the effectiveness of chemical reduction of nitrate in aqueous solution using metals. Specifically, we are studing the kinetics of nitrate transformation in the presence of iron metal under various pH conditions. Our objective is to evaluate the treatment feasibility of the technology and to gain mechanistic insight into the reduction of nitrate by zero-valent iron. (If you find any false information hear, please contact webmaster!)