Schaefferstown Pa And the Nitrates in the Water 2004
...ugh the soil. The extra nitrate is carried through the soil and into the groundwater supplies, contaminating the water. Humans consume nitrates in the plants and animals they eat and the water they drink. In Schaefferstown, the nitrates in the water are mostly a result of runoff from agricultural lands. The agricultural lands use the nitrates in fertilizers for their soil and the nitrates are also found in animal waste (picture A1), which they also use on their soil. The total amounts of nitrogen needed on a farm through manure production and/or thorough fertilizers are usually more than the crop needs. Also, storage of manure in open fields with no protection from rain, overflows, and leaks all contribute to the contamination of the groundwater (pictures A1 and A2) (Agriculture Practices…). Good nitrogen management is needed when storing and applying fertilizers (Household Water…). The nitrates seep into the groundwater or runoff into streams contaminating the drinking water like what happened in Schaefferstown. At the time, when the nitrates got into the water in Schaefferstown, they stayed there and were not taken out. The town was over the maximum limit of 10 milligrams per liter of water, which was set in 1962 by the Public Health Service Drinking Water Standards (Contaminant Removal…). “In the United States more public water supplies have been closed due to the violation of drinking water standards for nitrate than from any other contaminant” (Agricultural Practices…). When nitrate in a public water supply, like Schaefferstown, reaches or exceeds the drinking water standards, costly measures must be taken. To remove the nitrates, the town got a Nitrate Removal System as seen in picture A7. If high amounts of nitrates are consumed it could be dangerous especially in infants. The most dangerous and talked about problem is called blue baby syndrome, also known as methemoglobinemia. In infants under six months, nitrates can have a toxic effects because the nitrate is broken down to nitrite in the infant’s stomach whereas in adults and older children have stronger stomach acid content which kills the bacteria (Nitrates and Coliform…). Nitrite reduces oxygen and could suffocate the baby. Some symptoms of nitrate poisoning can be confused with other illnesses and are usually subtle. These symptoms include vomiting, diarrhea and strenuous breathing. In other cases, infants will start to show obvious symptoms such as the skin, lips or nailbeds turning a grayish bluish color (Nitrates and Drinking…). These nitrates can also be harmful to certain adults and small children. Pregnant women can pass methemoglobin on to their developing baby and young children have shown delayed reactions to light and sound stimuli from drinking highly nitrated water (Nitrates in Drinking…). It is also said that there is a link between high nitrates in drinking water and gastrointestinal cancer however it is controversial (Nitrates and Coliform…). A 2001 study by Peter Weyer and his colleagues found that nitrates in drinking water at a level of 2.5 milligrams per liter (one-fourth the EPA standard of 10 milligrams per liter) increases the risk of bladder cancer (Miller, G. Tyler). Livestock can also get nitrate poisoning, especially cattle. Aborted calves and lowered milk production are two signs that of nitrate poisoning. Livestock can withstand much higher nitrate levels than that of humans (Nitrates and Coliform…). None of these problems have been found in Schaefferstown though. Before the nitrate removal system, Schaefferstown had no way of cleaning their water from the nitrates. The community was consuming these toxic materials and being endangered of getting ill. “Nitrate is a very soluble substance, easily dissolved in water and extremely hard to remove. Treatment for nitrate is, therefore, very complicated and expensive” (Household Water…). With the nitrate removal system, the nitrates are removed from the water by an “exchange process” where nitrate ions in the water are replaced by chloride (picture A8) ions from the resin bed (Contaminant Removal…). The resin bed is enclosed in an ion exchanger which consists of the tanks, piping, valves, monitors and controllers needed to operate the process as seen in the pictures A5, A6, A7 and A8 (Contaminant Removal…). This process does not break up the nitrate or turn it into something else. It simply removes it from the water and deposits it in the water brine. The nitrate removal system is similar to those used for home water softeners. This system has very low maintenance requirements. Operator time required to run the system is not more than a couple hours a week. The operators do not require highly specialized skills but should understand fundamental chemistry and be able to perform accurate nitrate analyses and be familiar with pumps, contro...