Fukushima cooling water: controversial discharge into the sea is getting closer

The start of Japan’s controversial removal of massive amounts of diluted cooling water from Fukushima’s core ruins is approaching. According to Japanese media, representatives of the nuclear regulatory agency want to inspect the systems to discharge the treated water into the sea this weekend.

There is massive criticism of the Japanese government’s plan in South Korea, among other places, and researchers around the world are discussing it controversially.

After completing a test run, Japan’s nuclear regulatory agency must conduct a preliminary assessment before it can begin discharging the water into a roughly half-mile-long undersea tunnel that empties into the ocean. This is expected this summer.

Removal can take decades. According to Japanese media, the director-general of the International Atomic Energy Agency (IAEA), Rafael Grossi, plans to come to Japan early next month to meet with Prime Minister Fumio Kishida.

At the Japanese Nuclear Power Plant (NPP) Fukushima Daiichi On March 11, 2011, a massive earthquake and a massive tsunami caused a supermelt. More than twelve years later, the reactors destroyed in the process still need to be cooled with water.

Due to infiltrating rainwater and groundwater, the amount of polluted water is increasing day by day. Until now it has been stored in hundreds of huge tanks, but now space is running out, according to operator Tepco.

According to the Japanese television channel NHK, the amount is now well over 1.3 million tons. That corresponds to about 97 percent of the tank capacity.

The government therefore decided in 2021 that the water would be diverted to the Pacific Ocean. The contaminated cooling water is filtered, but the ALPS filter system cannot filter out the tritium isotope. However, according to operator Tepco and the Atomic Energy Agency IAEA, this should not pose a risk.

Japan states that tritium is harmless to humans in small amounts. According to the NHK, the water is diluted to such an extent that the tritium concentration drops to about 1,500 becquerels per litre, which corresponds to one fortieth of the national limit value.

However, environmentalists, neighboring countries and local fishing communities are opposed to the project. The fishermen fear further damage to the reputation of their products.

“It sounds like a terrible idea at first, but it’s actually sensible and safe,” he argues Nigel Marks, professor of physics and astronomy at Curtin University in Australia.

Nuclear power plants around the world have been routinely discharging contaminated cooling water into the sea for decades. “And nothing bad ever happened,” says the scientist. The Pacific Ocean contains 8400 grams of pure tritium. Japan wants to release only 0.06 grams of tritium annually.

indicated against Robert Richmond, director of the Kewalo Marine Laboratory at the University of Hawaii, Japan’s plan for “premature and currently inadvisable”. The radiological environmental impact assessment prepared by the operator group Tepco was “poor and inadequate”.

The same applies to the monitoring plans, “which are not aimed at protecting the ecosystem, but only at detection”, according to the expert. The potential negative impacts come on top of other stressors that are already affecting the health of the oceans and the people who depend on them.

(dsc/sda/dpa)