During the spring flood or floods in a well or well, flood waters may get, after which they are considered infected.
You can use water from them only after appropriate cleaning and disinfection. This is a responsible and laborious process, so it will be better to order it to conduct a special team.
However, if you are confident in your abilities, then to obtain the necessary result will be best applied for advice to the local sanitary and epidemiological service, which will advise you effective means for disinfecting wells.
In the ring well, you should first determine the depth of water in order to calculate the required amount of disinfection agent.
Then you need to scoop all the water, clean the bottom from silt and cover it with a layer of pure gravel.
Walls and seams between the rings, a bucket, a cable, all the equipment and cover of the well should be treated with a solution of chlorine lime, at the rate of 2 teaspoons diluted in a 10-liter bucket of water.
If you have attracted water drilling at a low price, you should remember that a completely different method is required for their disinfection.
The significant depth of the well does not allow you to mix quite well a disinfecting solution with water. Therefore, in order to reliably rinse the well, it is necessary for a long time to continuously pump out water from it.