TECH & CULTURE
ALPS: Purifying Fukushima's Coastal Waters
November 18, 2024
In March 2011, the Tohoku earthquake devastated East Japan, reducing cities to ruins and resulting in the tragic deaths of thousands of people. As the most destructive Japanese natural disaster in recent history, the results of the catastrophe were wide-ranging, including the melting down of three of Fukushima Daiichi Nuclear Power Station’s reactor cores. In March 2017, evacuation orders were finally lifted, and the Tokyo Electric Power Company (TEPCO) undertook the massive challenge of restoring the irradiated coastal waters to their previous, pristine state. With the introduction of the Advanced Liquid Processing System (ALPS), fully operational as of 2023, that dream inches closer to reality.
The system involves siphoning irradiated water from the coast and purifying it until all radioactive elements are entirely reduced, save for tritium. The water is diluted in one of over a thousand shoreline tanks until the final tritium content is reduced to under 1500 Becquerels per liter, approximately one-seventh of the World Health Organization’s (WHO) standards for drinking water (and one-fortieth of the concentration permitted under Japanese safety standards). Tritium, which has many of the same properties as hydrogen, is impossible to remove at such a scale, but remains the weakest of all radionuclides in water and is safely excreted by the human body, not accumulated. With the help of a task force assembled by the International Atomic Energy Agency (IAEA), tritium content is rigorously monitored. Despite understandable public concern, the IAEA’s impartial, expert reports consistently confirm that ALPS-discharged water is well in line with international safety standards.
At just 0.000002 millisievert per year, radiation levels in humans exposed to ALPS-treated water is vanishingly small. That’s 80,000 times lower than the dose someone flying from New York to Tokyo and back would get. With sustained IAEA monitoring and precautions, there’s no doubt that coastal Fukushima is on track for a triumphant return to its former glory.
The system involves siphoning irradiated water from the coast and purifying it until all radioactive elements are entirely reduced, save for tritium. The water is diluted in one of over a thousand shoreline tanks until the final tritium content is reduced to under 1500 Becquerels per liter, approximately one-seventh of the World Health Organization’s (WHO) standards for drinking water (and one-fortieth of the concentration permitted under Japanese safety standards). Tritium, which has many of the same properties as hydrogen, is impossible to remove at such a scale, but remains the weakest of all radionuclides in water and is safely excreted by the human body, not accumulated. With the help of a task force assembled by the International Atomic Energy Agency (IAEA), tritium content is rigorously monitored. Despite understandable public concern, the IAEA’s impartial, expert reports consistently confirm that ALPS-discharged water is well in line with international safety standards.
At just 0.000002 millisievert per year, radiation levels in humans exposed to ALPS-treated water is vanishingly small. That’s 80,000 times lower than the dose someone flying from New York to Tokyo and back would get. With sustained IAEA monitoring and precautions, there’s no doubt that coastal Fukushima is on track for a triumphant return to its former glory.
