If you would like to disinfect your well, please do the following. It is critical that each step be performed properly:

Mix ½ gallon of household bleach (such as Clorox) in a bucket of water and pour it into the well.

Attach a hose to a tap beyond the pressure tank and run the water into the well for about 15 minutes. This circulates the bleach through the well.

Open all the cold water taps in the house and allow the water to run until you smell chlorine at each tap. This usually takes about 30 minutes.

Turn off the water and let it sit in the plumbing for at least 3 hours, preferably overnight.

You can then run the water at each individual tap until the strong chlorine odor is gone and then use the water as you normally would. The water should not be tested until all the chlorine is gone, which can take anywhere from 10 to 20 total hours of running time. You can run the water off more quickly by attaching a hose and draining the water outside, but you will get the truest indication if the disinfection was effective by waiting 2 to 3 weeks to retest. If you water still tests positive you should contact a plumber to discuss treatment options.