The 1990 EPA National Survey of Drinking Water Wells found that approximately 57 percent of the private wells tested contained detectable levels of nitrates. However, only 2.4 percent exceeded the EPA maximum contaminant level. In Colorado, nitrate contamination above the MCL occurs mainly in rural areas overlying vulnerable aquifers.
Protecting your drinking water supply from contamination is important for health and to protect property values and minimize potential liability. High nitrate levels often are associated with poorly constructed or improperly located wells. Locate new wells uphill and at least 100 feet away from feedlots, septic systems, barnyards and chemical storage facilities. Properly seal or cap abandoned wells.
Manage nonpoint sources of water pollution (fields, lawns) to limit the loss of excess water and plant nutrients. Match fertilizer and irrigation applications to precise crop uptake needs in order to minimize groundwater contamination
Best Management Practices for Fertilizer Use
Careful fertilizer management can reduce nitrate leaching to groundwater. Consider the following practices in planning your fertilizer program:
• Use soil and water analysis to determine exact nitrogen needs of crop (see fact sheet 0.500, Soil Sampling).
• Set a realistic yield goal for each field. Take the five-year average production of your field and add 5 percent to get an attainable yield goal.
• Credit all sources of nitrogen available to the crop, including manures, water, organic matter, legumes and residual subsoil nitrate.
• Split nitrogen fertilizer into as many separate applications as feasible (see 0.514, Nitrogen and Irrigation Management).
The high levels of nitrogen in groundwater are the increases incidence of methemoglobinemia or blue-baby disease. it caused by the child to develop a bluish or grayish tint around the extremities. If left untreated the baby will not receive enough oxygen...