How much chlorine should be in my treated well water?

Drinking water, if treated with chlorine, should have 1 ppm of free chlorine.

If you have more than 1 ppm of free (residual) chlorine in your drinking water, it is enough to keep your water safe from harmful organisms and bacteria. More than 1 ppm of free chlorine in drinking water can result in off-flavors, burning sensations, as well as harmful side effects. Chlorinated drinking water should not have a strong odor of chlorine.