■What should the dissolved components be treated with? The main treatment methods for each dissolved component are as follows: 1. Iron: Oxidation through pre-chlorination or aeration followed by filtration 2. Manganese: Oxidation with chlorine or similar substances followed by filtration 3. Nitrate nitrogen: Ion exchange, reverse osmosis, electrodialysis, biological treatment (denitrification) 4. Organic solvents (such as trichloroethylene): Aeration, activated carbon For PFOS and PFOA, methods include adsorption using activated carbon or ion exchange resins, and separation through membrane treatment. ■What does aeration do? It is a treatment that promotes good contact between water and air. In addition to driving volatile organic chlorinated compounds out of the water, it supplies oxygen from the air to the water, facilitating the oxidation of dissolved iron. However, depending on the form of iron, oxidation may not be fully achieved with aeration alone, so caution is necessary. ■There is a reason for the order of treatment! Ultraviolet treatment is only applicable when the turbidity and color of the water being treated do not hinder the process. Therefore, in well water with high turbidity or iron content, it is essential to remove these factors in the preceding stage.

■What to do when contamination is detected? According to the national guidelines for sanitary measures for drinking wells, when it is determined that health hazards may arise from the supplied water, the installer must immediately stop the water supply and follow the instructions of the health department. For wells where contamination has been confirmed, prefectures will encourage the installer to connect to the water supply. ■Switching to a treatment device or water supply Choosing between installing a treatment device or switching to a water supply is a decision that should be compared in terms of water quality and cost. ■Things to confirm before considering treatment 1. Items in the test results that are close to or exceed the standards 2. Whether the components are dissolved or floating as particles 3. The amount used for drinking water and the location where a treatment device can be placed 4. Who will be responsible for maintenance, such as replacing filter media or replenishing chemicals The distinction between dissolved components and particles is key in determining the appropriate treatment. ■What Torii can do Torii offers sodium hypochlorite (for disinfection), activated carbon for adsorption, and filtration devices for iron and manganese removal, among others. Based on the test results, we will assist you in organizing which treatments are necessary. Please feel free to consult with us first.