Shallow wells typically draw their water from surface water supplies and are often contaminated. Wells may also become contaminated during periods of heavy rain or flooding. These wells cannot be disinfected using the methods outlined below. You must pump the well out for an extended period of time, generally for 12 hours or more. Wait several days and then resample.
Chlorine is a highly corrosive chemical, especially in concentrated form.
Wear safety goggles, rubber gloves, and an apron to protect your clothes from splash. Chlorine can mix with these products to form a highly dangerous gas. While there are formulas for determining the precise amount of chlorine to use for disinfection, many homeowners do not know the depth of their well, making calculations difficult. One gallon of household chlorine bleach or one pound of chlorine tablets will adequately disinfect the average well in our area. If you have an extremely deep well, over 600 feet, you may use an extra half gallon of bleach, or pound of tablets.