- 14 Mar 2002
The solution to pollution is dilution.
Last week, the Japanese government approved Tepco's plan to release contaminated water stored at the crippled Fukushima Daiichi nuclear power station in 2023. So far, a staggering 1,2m tonnes of water have accumulated in 1,034 storage tanks on the site, with a daily increase of 170 tonnes used to cool the remaining nuclear fuel. Tepco will be running out of storage space by the end of 2022 and had been trying to secure permission to release the treated water gradually.
The contaminated water is purified through ALPS (Advanced Liquid Processing System ), a procedure that can remove 62 different types of radionuclides (including caesium and strontium) but not tritium, a radioactive isotope of hydrogen which remains in the tanks. If tritium levels remain high, the ALPS procedure can be repeated several times. So while tritium is radioactive, it is not nearly as dangerous as caesium-137 or strontium-90. Tritium is a weak beta emitter, and plastic sheet or human skin is sufficient to filter out most of the radiation. Unlike caesium-137 and strontium-90 (highly carcinogenic), tritium is not accumulated in the human body.
Taking the decision on the Basic Policy on Handling of ALPS Treated Water at TEPCO's Fukushima Daiichi Nuclear...
The Japanese government has repeatedly pointed out that small quantities of tritium pose no danger to marine life, fisheries, and humans. Released in small quantities, the tritium would dilute with seawater, resulting in levels so low that it could be safely ingested.
The request came after the Japanese politician claimed the water from the Fukushima No. 1 nuclear plant would be safe to drink.
The decision of the Japanese government - though approved by the IAEA - has, of course, triggered a fierce backlash from Fukushima's local fishing industry as well as neighbouring countries like Taiwan, South Korea, and China, which argue that Japan has no right to pollute the Pacific Ocean, a body of water shared by many nations and people.
What's ironic - or even hypocritical - is that China and South Korea regularly release contaminated water from their own nuclear power plants into the Pacific. Activism, as reported below, appears to be motivated by more than just ecological concerns.
More than 30 South Korean college students shaved their heads in front of the Japanese embassy in Seoul on Tuesday to protest Japan's decision to release water from its crippled Fukushima nuclear plant into the sea.
An effort to tarnish Japan's image in the lead-up to the 2020 Tokyo Olympics is one thing, but misleading the public with unfounded claims that disregard science is quite another.
A renowned German radio ecologist, Prof. Steinhauser of Hanover University, believes that the gradual release of cooling water is, in fact, the safest solution. Steinhauser was able to take water samples in the exclusion zone around the crippled plant in 2013 and later worked at Fukushima University. He dismisses two suggestions made by those who oppose Japan's plan: namely, the idea of adding more storage tanks (as they could easily leak and contaminate the groundwater) as well as the idea of evaporating the contaminated water (as radioactive hydrogen released in the air is more difficult to control; also, wind could disperse radioactive clouds to over long distances).
Steinhauser also sees no risks for the environment. "Tritium is not like mercury in tuna. Tritium is radioactive hydrogen and does not accumulate in any algae or plankton, but rather dilutes itself progressively." (article in German).
Two concerns remain:
- How can the Japanese government assure that only sufficiently decontaminated water with low levels of tritium will be released? The IAEA and other environmental watchdogs will have to be involved in the entire operation which will probably be conducted over many years.
- What about Fukushima's agriculture and fishing industry? Farmers and fishers will continue to depend on subsidies. Their products will remain subject to import bans.
Updates to these issues to follow. Let me know what you think of Tepco's plan.