URBANAAn abandoned well poses one of the greatest threats to groundwater, said Mike Hirschi, University of Illinois Extension water quality specialist. It provides a direct, unhindered route for pollutants to reach an aquiferan underground water supply.
According to Hirschi, the best and only safeguard against this situation is to properly seal all abandoned wells. Sealing a well is generally not an expensive process, but it must be done correctly, preferably by a licensed groundwater professional.
Homeowners have the right to seal their own wells, Hirschi added, as long as they accept all responsibility for sealing the wells in compliance with the Illinois Water Well Construction Code and all pertinent county codes.
In Illinois, an estimated 400,000 private water wells provide drinking water to about 1.3 million people, reports the Illinois Department of Public Health (IDPH). Many of these wells are abandoned every year when the owners either install new wells or switch to a community water supply. Roughly 2,000 abandoned wells are sealed each year in Illinois, the IDPH says.
For those homeowners who intend to take this task on themselves, Hirschi recommends the following eight-step process:
1. Contact the local health department to obtain a water-well sealing plan form. After consulting with the local health department, complete the sealing plan, which includes a description of the particular sealing method, as well as materials and equipment to be used. Then submit the sealing plan to the local health department.
2. After you receive written approval of your plan, notify the local health department at least 48 hours before you begin sealing and make arrangements for an inspector to be present at the time of sealing.
3. Remove all material from the water well, such as the pump, pipe, pump cylinder and electric cable. Be sure to use the proper hoisting equipment, safety devices and safety precautions.
4. Measure the depth and diameter of the well and the static water level. The static water level is the distance from the soil surface to the level of non-pumping water in the well.
5. Make sure there is no foreign matter in the bottom of the well. Remove all debris before sealing.
6. Disinfect the well, following the State of Illinois Water Well Construction Code. You must use the correct amount of chlorine as prescribed by the state codea concentration of 100 parts per million.
7. Seal the well in accordance with an approved plan.
8. Complete the water well sealing affidavit and submit it to the local health department not more than 30 days after a well is sealed.
The type of material used to seal the welland the specific sealing methodall depend on the type of well, Hirschi said. For instance, sealing an abandoned large-diameter bored well will be different than sealing an abandoned small-diameter drilled well.
To obtain information on materials and sealing methods, the best contact is your local public health department.