Japan temporarily halted the discharge of treated wastewater from the Fukushima Daiichi Nuclear Power Plant after a powerful offshore earthquake (around magnitude 7.5–7.6) struck the country’s northeastern coast, triggering tsunami warnings and widespread safety checks.
The stoppage, confirmed by plant operator Tokyo Electric Power Company (TEPCO), was described as a precautionary measure and not the result of any system failure.
“This is a standard safety protocol carried out immediately following major seismic activity,” TEPCO said.
Earthquake and Tsunami Alerts Raised Fears
The earthquake struck off the coast of Aomori Prefecture, prompting the Japan Meteorological Agency (JMA) to issue tsunami warnings of up to 3 metres in parts of northeastern Japan. Tens of thousands of residents were urged to evacuate as authorities monitored coastal conditions.
Actual tsunami waves observed later ranged between 20 and 70 centimetres, and warnings were eventually downgraded and lifted.
No Abnormalities Found at Fukushima Plant
Despite the strength of the tremor, Japan’s Nuclear Regulation Authority and TEPCO confirmed:
- No structural damage to nuclear facilities
- No leakage of radioactive materials
- No malfunction in wastewater treatment systems
However, authorities ordered the temporary suspension of ocean discharge activities until full safety diagnostics were completed.
Why Fukushima Wastewater Is Being Released
Since the 2011 Fukushima nuclear disaster, contaminated water has been stored and treated using the Advanced Liquid Processing System (ALPS) to remove most radioactive elements. The treated water, heavily diluted, has been released gradually into the Pacific Ocean under international safety guidelines from the International Atomic Energy Agency (IAEA). World Nuclear Association
Japan plans to release over 1 million tonnes of treated water over the coming decades. The process remains controversial, particularly among neighboring countries and fishing communities.
Global and Regional Reactions
China and several Pacific nations have previously raised concerns over the environmental impact of the discharge. However, independent testing by international and regional laboratories has consistently shown no abnormal radioactive levels in sampled seawater and marine life.
Recently, China began easing restrictions on Japanese seafood imports after independent verification of water safety.
What This Pause Means
Important clarification for the public:
✅ The halt was not caused by a leak
✅ It was a preventive safety action
✅ The system functioned as designed during the emergency
Operational pauses like this are part of Japan’s reinforced safety culture following the 2011 nuclear disaster.
Looking Ahead
Japan continues to monitor seismic activity in the region, with authorities warning that strong aftershocks may still occur. Wastewater discharge is expected to resume once inspections are fully completed and safety is confirmed.
References
- Reuters. (2025, December 9). Japan lifts tsunami warning after 7.5-magnitude earthquake. Reuters
- Reuters. (2025, December 8). Powerful 7.5-magnitude earthquake strikes Japan’s northeast. Reuters
- Associated Press (AP). (2025, December 8). Magnitude 7.5 quake in northern Japan injures 23 people and triggers tsunami. AP News
- Xinhua / The Star Malaysia. (2025, December 9). Ocean discharge of Fukushima nuclear-tainted wastewater halted after 7.6-magnitude quake hits northeastern Japan. The Star
- International Atomic Energy Agency (IAEA). (2025). Fukushima Daiichi ALPS treated water discharge – Safety reviews. IAEA
- International Atomic Energy Agency (IAEA). (2025). Timeline of safety reviews for ALPS-treated water. IAEA
- Ministry of Economy, Trade and Industry (Japan). (2025, September 16). IAEA review on the safety of ALPS-treated water discharge. Ministry of Economy, Trade and Industry
- Korean Broadcasting System (KBS World). (2025, July 30). TEPCO halts wastewater release after tsunami warning. KBS World Radio
- International Atomic Energy Agency (IAEA). (2025, December). Tritium level far below Japan’s operational limit in ALPS-treated water. IAEA
- Reuters. (2023, August 24). Fukushima: Why is Japan releasing treated water and is it safe? Reuters
