Normalcy returning to Fukushima fishery, but new reactor cooling water releases loom

As the tenth anniversary of the East Japan earthquake, tsunami, and Fukushima Daiichi nuclear disaster approaches, fishery cooperatives in Fukushima Prefecture are making progress toward recovery by reopening damaged port cargo handling and auction buildings and sales outlets – even as new releases of cooling water from the crippled reactor appear imminent.

The 11 March, 2011, disaster resulted in fishing being banned in the prefecture due to radioactivity. Since then, the national government, in cooperation with the prefectural governments and fisheries cooperatives, has monitored radioactive materials in fish and fishery products. In trial fishing, the number of samples in which radioactive materials above the standard limits were detected decreased over time, and in marine species – for four years after June 2015 – there were no samples collected in Fukushima that exceeded the standard. A study performed in 2017 found that Fukushima Daiichi radiation was no longer a danger to seafood-eaters.

In 2018, more than 6,000 samples representing about 200 species were tested, and the highest value detected was 51 becquerels per kilogram, well under the government standard of 100 becquerels per kilogram. But in January 2019, an ocellate skate was found to have a radioactive cesium level exceeding the limit, and as a result fishing of that species was banned for a year. On 25 February, 2020, all species were again cleared for sale.

As the fishing conducted in the prefecture was limited to trial fishing in order to carefully monitor radioactivity, the volumes have still been limited. In 2019, they amounted to only 14 percent of the pre-disaster level. Now that all species have been approved for shipment, and many formerly closed areas have been reopened to residents, the route has been cleared to ramp up fishing volumes and reopen market facilities in the area.

On 8 April, 2020, the Ukedo regional wholesale market in the town of Namie in Fukushima Prefecture, once a part of the “no-go zone,” reopened. Then in July the Isobe processing facility direct sales office, which sells processed local marine products, reopened. And in December, the Shinchi-cho Fisherman’s Beach Port cargo handling area, where landings are sorted and auctioned, was rebuilt and reopened. Fishing activity is gaining momentum as more local facilities come back online, eliminating the need for fishers to truck catches to sales facilities in other areas.

But the possibility of fresh releases of cooling water stored at the site of the crippled reactor may spook customers, even if it does not pose a direct threat to health. The Japanese government may allow Tokyo Electric Power Company (TEPCO) to dump more than 250 million gallons of contaminated water accumulated in tanks around its Fukushima nuclear power plants into the ocean. The government and the company had previously adopted the strategy of building more and more holding tanks, but room to expand is running out.

The water has already been treated by multiple facilities, including a multi-nuclide removal facility (an advanced liquid processing system, or “ALPS”), which removed most of the radioactive materials – including cesium and strontium – but not tritium. Tritium is difficult to separate from water because it resembles hydrogen, a natural component of water.

Before the accident, tritium in cooling water was diluted with seawater to reduce the concentration to an acceptable level, and water was routinely released into the sea. This will likely be the approach taken to free up room in the tanks.

In practice, releasing cooling water is not very dangerous. Tritium has a radioactive half-life of 12.3 years, but its biological half-life in the human body is only 10 days, and in fish is less than two days. This is because tritium easily bonds to water, replacing the hydrogen atom. So as fish take in and expel water, the tritium is carried away rather than accumulating in tissues and moving up the food chain.

The main danger of the policy is that it may harm public perceptions about the safety of seafood from Fukushima and its neighboring prefectures. Foreign countries have been gradually removing restrictions on importing Japanese seafood, and a new release might act as a justification for extending bans – as in the case of South Korea – or imposing new restrictions. A World Trade Organization settlement panel ruled in favor of Japanese seafood in 2017, but that decision was later reversed in 2019.  

At a meeting of the parties to the London Convention and Protocol (a treaty for controlling marine pollution) on 14 December, the South Korean Ministry of Oceans and Fisheries stated that the release of contaminated water from the Fukushima Nuclear Power Plant into the ocean was not a sovereign decision for the Japanese government to make, but should be subject to international negotiations. China, Russia, and Canada supported this position, while the U.S. said that it is a matter for the International Atomic Energy Agency (IAEA) to oversee. The IAEA has called for an environmental impact statement prior to any release.

Domestically, a release would harm efforts by cooperatives in the prefecture to re-establish sales channels and promote their products, as customers’ fears – now calming – may be rekindled. With fear of radiation posing a greater obstacle than the radiation itself, the fate of Fukushima’s fishing industry is still in flux.  

Photo courtesy of Santiherllor/Shutterstock