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57 Ways To Protect Your Home Environment (and Yourself)
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35. Test Your Water For Coliform Bacteria And Nitrate

testing water

The two most common water contaminants are coliform bacteria and nitrate. Municipal water systems regularly test for these contaminants, but if you have a private well, it’s up to you to make sure your water is tested.

The Illinois Department of Public Health charges a nominal fee to test for coliform bacteria and nitrate. This fee varies among local health departments. Annual testing for coliform bacteria and nitrate is a good idea, especially after a heavy spring or summer rainstorm and whenever your well is flooded. You should also disinfect the well and test the water any time you open the well.

septic system diagram

Common sources of bacteria are waste, septic systems, and surface water that gets into the well. Testing for coliform bacteria is important because it is an “indicator organism,” which means that its presence may indicate the existence of other harmful bacteria in your water supply. Using an indicator organism is necessary because testing for all harmful bacteria would be difficult and expensive.
collecting water sample

If your water test shows the presence of coliform bacteria, your water has some degree of contamination. The state cannot require someone with a private water supply to correct the condition, but it will recommend that you disinfect your water system and then submit another sample for analysis. The local department of public health, a licensed well driller, or a pump repairperson can further explain the correct techniques for disinfecting a well. Use bottled water until you are able to bring bacteria levels under control.
fertilizer spreader

Common sources of nitrate in groundwater are fertilizers, septic systems, livestock waste, and naturally occurring nitrate in the soil.
maximum contaminant levels

A water-testing lab will describe nitrate concentrations in one of two ways. The lab may describe the nitrate concentration as the amount of actual “nitrate” or as the amount of “ nitrate-nitrogen.” The maximum contaminant level for nitrate in a public water supply is 44 parts per million (ppm), which is the equivalent of a nitrate-nitrogen concentration of 10 ppm.
testing water

If unacceptable nitrate levels are found in your water, do not boil the water. Boiling water does not eliminate nitrate. In fact, it causes some of the water to evaporate, which increases the concentration of nitrate in the remaining water.
bottled water

Use bottled water until you can treat the well water, eliminate the pollution source, or make repairs (if there is a problem with well construction).
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