Which action should be taken to ensure that the water introduced into a well during construction is safe?

To ensure the safety of water introduced into a well during construction, it is crucial that the water is clean and potable. This means that the water should meet health standards for drinking water, free from harmful contaminants and pathogens that could compromise the safety of the well water supply.

Using clean and potable water reduces the risk of introducing bacteria, viruses, or chemical pollutants into the well. If contaminated water is used, it can lead to potential health hazards not only for users of the well but also for the surrounding environment. Thus, ensuring the initial water quality is of utmost importance in the construction process.

While chlorination, boiling, and filtration are methods used to treat water, they are unnecessary if the water being used from the outset is already clean and potable. These methods are typically employed in situations where the water's safety is questionable or when there is an existing contamination issue, rather than for construction activities. Therefore, starting with water that is verified as clean and potable forms the best practice for well construction.