Disinfection

Hello Nathalie,

disinfection of wells could be very tedious job if contamination is very high. Some time it is better to dig new wells. first step should be to determine the type and level of contaminations. You can simply fallow the guidelines provided by WHO

http://www.who.int/water_sanitation_health/publications/2011/tn1_cleanin...

You should be able to acquire a 3rd party bioassayed system to the USEPA Guidelines for water disinfection utilizing ultraviolet at a cost less than $12,000 USD.  Systems without validations will be less expensive howver you tak the risk to public heath that they are sized correctly and will deliver the disifnection you need.