Here’s the latest of our news bulletins from the ongoing crisis at Japan’s Fukushima Daiichi nuclear power plant.
Nuclear Regulation Authority
Japan’s Nuclear Regulation Authority (NRA) is in the process of reviewing safety standards for nuclear power plants, and plans to abandon previous government guidelines, which only took earthquakes and tsunamis into consideration as they were assessing safety. Pre-Fukushima safety guidelines were voluntary agreements created by the plant operators themselves, but the Fukushima nuclear disaster highlighted the ineffectiveness of that arrangement. The new guidelines, which will better conform to international standards, will reportedly assess reactor safety in case of other major disasters, including terrorist attacks; airline crashes; volcanic activity; release of toxic gasses; and sudden jellyfish attacks of seawater intake pipes, which can affect cooling of nuclear fuel and lead to meltdowns. The NRA plans to submit an outline of its review in January, and will present a complete version by the end of July. (Source: NHK)
Other Nuclear Politics in Japan
Although the Japanese government published the Innovative Strategy for Energy and the Environment earlier this month, promising complete eradiation of nuclear power by 2039, plans have apparently stalled as Akio Mimura, Chairman of the Fundamental Issues Subcommittee of the Advisory Committee for Natural Resources and Energy, has declared he will not review the new energy plan. Mimura said that allowing power companies to continue working on reactors already under construction is inconsistent and confusing. The move has infuriated Yukio Edano, head of the Ministry of Economy, Trade, and Industry (METI), who along with the Democratic Party of Japan (DPJ), is pushing to make sure that nuclear power is an issue in the upcoming Lower House Elections. Mimura added, “The government’s strategy lacks consistency. Its goal is vague.” However, some analysts and government insiders charge that his tactic may simply be an effort to postpone energy discussions until the opposition party, the Liberal Democratic Party (LDP), which leans pro-nuclear, takes power.
Kansai Electric Power Company (KEPCO), operator of the Oi nuclear power plant in Fukui Prefecture, site of the only two online reactors in Japan, said that it will submit an interim report to the government later this week, but has not discovered any new data to suggest that the F-6 fault below the Oi reactors is active—although it did not definitively declare that the fault is inactive. However, the NRA plans to conduct its own seismic survey starting on Friday. The government ordered KEPCO to study the area beneath the plant after scientists raised concerns that the fault might be active. Japanese law prohibits building nuclear reactors on active faults, because it places them at high risk for a nuclear disaster should an earthquake occur. If this fault is found to be active, the plant could be forced to shut down. Meanwhile, Kunihiko Shimazaki, a seismologist and Deputy Chairman of the NRA, is pushing to broaden the “active fault” definition to any that have moved within the last 400,000 years, a decision that would impact the Oi plant as well as others across the country. The current definition includes any movement that has occurred within the last 120,000 to 130,000 years.
Almost 20 months after the Fukushima nuclear disaster, ongoing fears of radiation contamination continue to adversely affect the tourism industry in Fukushima Prefecture, including fishing camps and towns known for growing and raising local cuisine and other delicacies. In Gunma Prefecture , visitors to Akagi Onuma, a lake known for smelt fishing, have declined by 90%. “Revenue has almost dried up since the earthquake,” said Takeshi Aoki, who manages a lakeside inn there. Smelt fishing, which was prohibited last year, has resumed, but people are not allowed to take the smelt home, because some fish caught has exceeded the government’s limit of 100 Bq/kg of radioactive cesium. “You cannot enjoy smelt fishing unless you can eat the fish after pulling it from the water. I hope tourists will soon be allowed to take the fish away with them,” Aoki noted. An official from the Ministry of Agriculture, Fisheries, and Forestry said, “We know that some tourist sites and industries have been affected because food shipments are suspended when food is in season. But we cannot lift the ban unless the amount of radioactive cesium is below the standard—and steadily so—in order to protect the safety and security of consumers.”
A new survey conducted by researchers at Fukushima University shows that 60% of residents forced to evacuate from Fukushima Prefecture, as well as those still living there, say they hope to return or stay, assuming that there were no radiation fears with which to contend. Most named current employment or fear of financial burdens as a result of relocation as reasons to stay.
Contamination, Including Human Exposure
A new study led by Ken O. Buesseler of Massachusetts’ Woods Hole Oceanographic Institution reveals that 40% of fish (including cod, halibut, and flounder) caught off the coast of Fukushima Prefecture is contaminated with cesium-134 and -137, exceeding the government’s safety limits of 100 Bq/kg. The fact that saltwater fish generally do not remain radioactive for a long time indicates that the contamination is recent.
Buesseler believes that the source of the contamination is either radioactive sediment that has settled on the ocean floor and is now entering the food chain, or from contaminated water continuing to leak into the ocean from the reactors themselves. He explained, “The numbers aren’t going down. Oceans usually cause the concentrations to decrease if the spigot is turned off. There has to be somewhere they’re picking up the cesium. Option one is that the seafloor is the source of the continued contamination. The other source could be the reactors themselves.” The study used data collected by Japan’s Ministry of Agriculture, Fisheries, and Forestry in the year following the nuclear disaster. TEPCO reported it has no active knowledge of leaks, and said that the most recent leak of radioactive water pouring into the ocean was in April. However, utility officials admit they cannot rule them out. Four-fifths of the radiation that spewed from the Fukushima plant in the days and weeks following the disaster ended up in the ocean, either via wind or contaminated water intentionally or unintentionally released into the sea by TEPCO.
The Woods Hole study means that the fishing industry in Fukushima could be decimated for many years. The sale of 36 different species of fish caught in Fukushima has already been banned because of excessive radiation levels, and only sales of some types of octopus and sea snails are allowed, provided they test within government limits. But sales are still down. “Given the 30-year half-life of cesium-137, this means that even if these sources of contamination were to be shut off completely, the sediments would remain contaminated for decades to come,” Buesseler said. However, contamination could last much longer if the radiation is coming from leaks in the reactor vessels and spreading to groundwater, which then leaches into the ocean, as many scientists suspect. Radiation levels near the reactors remain astronomically high, and it will be years before humans or even robots can get close enough to identify and fix them. The study was published in the most recent issue of the journal Science.
Decontamination and Waste Disposal
Researchers from the University of Kitakyushu have discovered a new way to store radioactive waste from the Fukushima disaster, as the government continues to struggle with permanent storage options. The researchers plan to build structures made of polyethylene panels, filled with dirt and sand, around nuclear waste. The panels, which cost $190 for each cubic meter of waste, reportedly block up to 97% of radiation. However, they only last for 50 years. Much of the waste from the Fukushima crisis will remain highly radioactive for decades, and some for hundreds and even thousands of years. Japan’s Environment Ministry is currently testing the panels in Fukushima Prefecture. (Source: NHK)