Which of the following is NOT a very common method of disinfection at wastewater treatment facilities?

In wastewater treatment facilities, common disinfection methods include chlorine, ozone, and UV light, all of which are widely used due to their effectiveness in eliminating pathogens and ensuring water safety. Chlorine has been traditionally used for its strong disinfectant properties and ease of use. Ozone is also an effective disinfectant, known for its ability to oxidize and kill a range of microorganisms without leaving harmful residues behind. UV light disinfection is gaining popularity due to its ability to effectively inactivate pathogens through exposure to ultraviolet radiation, making it a chemical-free option.

In contrast, xenon is not typically employed as a method for disinfection in wastewater treatment processes. While xenon does produce ultraviolet light, its application is not as consistent or practical compared to UV light systems designed specifically for this purpose. Therefore, the choice of xenon as a disinfection method is not common in wastewater treatment facilities, differentiating it from the other options.