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Fact Sheet Nitrates in Drinking Water Nitrate (as NO3-N) is a colorless, odorless, and tasteless compound. It is the naturally occurring form of nitrogen that is found in soil and available for use by plants. It is also a highly soluble form of nitrogen and can leach, moving quickly with water through the soil and into groundwater. In moderate amounts, nitrate is a harmless constituent of food and water. The major human intake of nitrate is from food, rather than from water. The Environmental Protection Agency has established a MCL (maximum contaminant level) of 10 mg/l or ppm of nitrate (as NO3-N) in drinking water. The MCL was adopted chiefly to protect young infants. Levels exceeding the MCL have been associated with methemoglobinemia, commonly referred to as blue baby which usually only effects young infants. Water supply wells should be tested yearly at a qualified laboratory. Tests results higher than the MCL should be verified. Nitrate levels often vary seasonably and retesting every few months may be warranted if levels are elevated. Sustained high levels may indicate the need for treatment. Water treatments for nitrogen include distillation, reverse osmosis, ion exchange or blending. Prevention is the best way to protect your health and your property. Identifying and treating potential sources is a first step to prevention. High nitrate levels can be associated with poorly constructed or improperly developed wells. Highly permeable aquifers are especially susceptible to contamination from land use activities. Maintaining acceptable setbacks, properly sealing and capping abandoned wells, and properly developing new wells will help minimize your risk of contamination from sources such as agricultural land uses and septic systems. Decisions about your water should be based on reliable information. A responsible sampling program is the first step. ---PAGE BREAK--- Management Options Distillation: water is boiled and the resulting steam is caught, condensed and used for drinking. Nitrates and other minerals are left in the boiling container and disposed of in an acceptable manner. Reverse Osmosis: water is forced under pressure through a membrane that filters out minerals and nitrate (including about half the volume of water). Ion exchange: water passes through an exchange unit and over special resin beads that are charged with another ion such as chloride. When the water passes over the beads, they give up the chloride and take up nitrate. The beads are recharged as needed. Blending: water with low levels of nitrate can be mixed with high nitrate water to lower the overall concentration to an acceptable level. New Well: drilling a new well in a less susceptible location or drilling to deeper water with lower nitrate levels may be feasible. Bottled Water: using bottled water for drinking and cooking may be the simplest option. Public Water: if not already available, extending public water supplies to affected households may be a viable long-term solution. For information about your water supply well, call the Cortland County Health Department at 753-5035. For information about groundwater resources and nonpoint source pollution contact Cortland County SWCD at 753-0851 x3.