ALPS-Treated Water Ocean Discharge Begins — First in History for Fukushima

On August 24, 2023, TEPCO began the first ocean discharge of ALPS-treated water through an undersea tunnel extending 1 km offshore. The initial release rate was ~460 m³ per day, diluted with seawater to achieve tritium concentrations below 1,500 Bq/L (~1/40 of the WHO drinking water guideline and 1/7 of Japan's regulatory limit). China immediately banned all Japanese seafood imports; Hong Kong and Macau followed with partial bans. Protests occurred in China, South Korea, and Japan. Japan and IAEA deployed offshore environmental monitors that initially detected no abnormal radioactivity.