Disinfection with a chlorine solution will usually eliminate bacteria and viruses if they entered the well during construction or repair of the well. Disinfection or treatment will not provide a permanent solution if the contamination is caused by faulty well construction, a failing septic system, surface water contamination or some other ongoing problem. In that case, it will be necessary to repair the well, construct a new well, or remove the source of contamination.
Step 1: Put any type of water treatment systems, such as water softeners, iron removing equipment, in-line filters, etc., on by-pass. This is done to prevent the small screens in these units to become plugged up with possible debris and minerals that will become loose during the chlorination process.
Step 2: Shut off power to well. Remove well cap or seal from top of well casing. Submersible pumps may be suspended from some types of well caps and well seals. If you are unsure of the wellhead type, contact a pump installer or driller to chlorinate the system.
Step 3: Mix the granulated chlorine with 2-5 gallons of water. Then slowly pour the proper concentration of chlorine into well (See Table 1). Care must be taken to prevent chlorine solution from splashing and coming in contact with skin or eyes. It can be hazardous putting dry chlorine base products into the confined space of a well – a violent reaction may occur.
Step 4: Once all chlorine is poured into well, wait 20-30 minutes for chlorine to settle in the well. Then turn power back on and attach a gardening hose to an outside spigot. With water running, place hose into well and run for 20-30 minutes until the scent of chlorine is detected coming from discharge end of the hose. This indicates chlorine has circulated throughout the well system. If a strong chlorine odor is not present at this point, it may be necessary to add additional chlorine.
Step 5: Now, with chlorinated water coming from the hose, rinse the inside of the well casing and the top of the pitless adapter. This process will wash any bacteria down into the chlorinated water. Allow an additional 30 minutes of circulation.
Step 6: Open the cold water faucets in the house (bathroom, kitchen, etc.) one at a time, until chlorine is detected. This will disinfect the plumbing system in your house. Chlorine should remain in the well for a period of (24) hours for bacteria or (8) hours for water quality problem and well/pump system repairs. Do not consume the water, do laundry, or bathe while chlorine remains in your system. Limited toilet flushing is permissible.
Step 7: After the suggested time for disinfection has expired, run an outside hose to free the well of all the chlorine. Do not run chlorine into your septic system. Run the water at a rate of approximately five (5) gallons per minute & monitor the end of the hose throughout the flushing process to verify continued flow. Debris may temporarily plug up the outside hose spigot. If this occurs, open & close the valve quickly to dislodge debris & continue flushing. Run water away from any vegetation.
Note: Clearing well of all traces (odor) of chlorine can take from 3 to 48+ hours. For the next few days you may notice some discoloration and particles in the water. This is normal and will clear with water usage. After flushing all chlorine and sediment from the well, you may place your softener back in service.
Aqua Well & Pump Systems, Inc.
“Accredited Water Specialists”