Six years ago, three nuclear reactors were crippled in Fukushima, Japan, when a tsunami knocked out power to the cooling units, and flooded the generators mistakenly kept at sea level. What was termed a cultural disaster caused a nuclear meltdown and over 70,000 nuclear refugees have still not been able to return home.
It is widely accepted in Fukushima that there is a perception gap between the reality of the problem, and what media outlets, both reputable and fake, have claimed the problem to be. So when recent reports came out that radiation in Fukushima was rising, I began to do my homework to discern what was really happening and what was “fake news.”
Recently Tokyo Electric Power Company (TEPCO) began sending robotic cameras into the primary containment vessels (PCV) that house the damaged reactors. However, due to extremely high levels of radiation, the robots keep breaking. Within the last two weeks, two cameras have broken—including the one on a scouting mission for the robot meant to locate the radioactive fuel.
According to TEPCO, “The previous highest radiation level was about 73 Sv/h measured in March 2012, so we designed cameras and robots to tolerate that level of radiation (about 100 Sv/h) for 10 hours for the investigation this time. The estimation of radiation levels (as high as about 530 Sv/h at a certain point) was more than we expected, but based on the findings, we proceed with further steps with some modification, necessary, to investigate inside the Unit 2 PCV with the Scorpion robot.”
There has been no change to radiation levels outside of the PCV, the power company added. “Extra precautions have been taken to prevent leaks of radiation during the investigation. The penetration pipe through the PCV wall is tightly shielded, and the work area is pressurized so that air only moves from the outside into the PCV and not the reverse.”
To find out more, I contacted Safecast, a citizen science network that bills itself as neither pro-, nor anti-nuclear. Safecast’s team of volunteers have developed the bGeigie handheld radiation monitor, that anyone can buy on Amazon.com and construct with suggested instructions available online. So far over 350 users have contributed 41 million readings, using around a thousand fixed, mobile, and crowd-sourced devices.
Here is what Azby Brown, Safecast’s lead researcher, has to say in an interview.
Let’s recap. TEPCO sent in a robot, it captured pictures before frying, and they stitched the photos together and found the hole. Inside the hole are extremely high levels of radiation, higher then ever measured before. They believe this is THE hole, created by melting radioactive material.
The first step in TEPCO’s recent investigations deep inside Unit 2’s reactor was to insert a camera on a long telescoping pole through an existing maintenance opening. It was not a robot. It captured striking images of what appear to be melted metal spattered on floor decking and other elements inside. They also detected a hole in the steel floor decking about 1m by 1m [about 10 square feet]. They were not able to actually see a hole in the steel reactor pressure vessel (RPV) above, but the working assumption is that the hole in the decking was caused by molten core material mixed with steel falling through.
Also, it seems likely that the material spattered around is a similar mix of core and steel, but some will have to be removed and tested to be sure, and TEPCO is cautiously waiting to until they’ve done that to confirm.
A few days after the telescoping-arm investigation, a small-tracked cleaning robot with a high-pressure water nozzle and a scraper was inserted. This operated for 2 hours before the radiation had degraded the camera too much to continue. Neither the telescoping unit nor the cleaning robot had an actual radiation detector, and radiation levels were inferred from camera noise and degradation of the cameras. TEPCO’s first announcement was that radiation levels were estimated to be as high as 530 Sv/hour; the succeeding estimate was over 600 Sv/hr. Either would be fatal to a human after a few minutes’ exposure.
Finally, on Feburary 16, Tepco inserted a second robot into the reactor. This one is called the “Scorpion” because it has a folding “tail” containing powerful lighting and a camera. It operated well for about 30 minutes before becoming immobile, but was able to obtain about 6 hours of video images as well as better radiation measurements, which showed maximum levels of about 210 SV/hr. While this is lower then the previous estimates, it is also considered more accurate and within an order of magnitude. It would also be fatal to humans after a few minutes’ exposure.
What does this mean for the cleanup of the disaster? is this a breakthrough or a setback?
These investigations are essential, and the fact that they’ve been fairly successful so far is a step forward. At the same time, the high radiation levels are sobering, and may mean that the timeline for removing the melted fuel and decommissioning the reactors will be longer than hoped.
Why does the world’s media claim a spike in the radiation, but Safecast is telling people that perhaps it’s not as bad as it seems. What makes you sure of this?
There’s no simple answer for why the findings were misrepresented in the media. TEPCO probably should have stated more clearly that they were measuring these high-radiation areas for the first time, not that radiation levels were rising. Some media posted alarming headlines about rising radiation levels, but their stories were actually pretty factual. Other media have a business model that uses “clickbait” and alarmism intentionally, regardless of fact. This time all these factored into the misreporting. Safecast has a network of real-time radiation sensors in Fukushima, including several within a few kilometers of the Daiichi plant. None of these have showed a spike in radiation, and no other official or independent monitoring has either.
Where are these high levels coming form?
Highly radioactive molten fuel almost certainly dropped to the 7m [23-foot] thick concrete floor of the reactor building beneath the RPV in March 2011. TEPCO believes that it is now covered by about 30cm [a foot] of water, which is being constantly purified and recirculated. It seems to be a very safe presumption that high radiation levels are from this core material, which has likely solidified.
Is the radiation contained? From where is the radiation still leaking?
It’s not fully contained, in that some of the recirculated cooling water, which becomes contaminated by contact with the core material, leaks out of the building, presumably through cracks in the basement walls of the reactor. Lots of measures have been taken to try to contain and minimize this, but none have been fully successful yet. Many of the steps being taken now are to prepare for locating and closing these leaks. This will be several years in the future at best, however.
Why has it taken so long to reach this hole? How do you imagine it can be dealt with finally and totally to decommission the plant.
In order to insert the telescoping arm and the robot, human workers need to have access to the maintenance opening. That area has high radiation as well — though not as high as inside the reactor. It took TEPCO much longer than initially estimated to decontaminate these areas sufficiently to allow the workers to perform their tasks with minimal risk. TEPCO and its partners have suggested several approaches for removing the melted fuel and dismantling the building, all of which rely heavily on developing new remotely operated and robotic technology. Again, this process will take decades.
Why is third-party citizen science reporting more believable than government information?
We believe that groups like Safecast can function independently of either pro-nuclear or anti-nuclear bias, which government agencies in Japan and abroad have not been able to fully free themselves from. Certainly governments are perceived by many as biased even when their information holds up. Our model depends on citizens themselves taking measurements and reporting them, so they can have full confidence in their data and in the system itself. We think our model can be widely adopted in other areas as well, from environment to food safety to supply chains. They key is the openness of the entire system.
In the era of fake news and misinformation, what can people do to verify these results for themselves?
There’s no substitute for doing the homework, becoming technically and media-literate, and informing oneself. Radiation issues are largely scientific, but as we’ve seen in the current political situation in the U.S., other issues are ripe for abuse and manipulation as well. We encourage people everywhere to be skeptical and to become skilled at fact-checking. This is only possible with adequate education.
As far as radiation and Fukushima are concerned, it’s usually pretty obvious when a website is distorting or manipulating information. But we’ve seen good journalists fall prey to bad info as well.
Safecast is always available to answer questions from the public as objectively as possible. Readers should feel free to contact us at email@example.com. As far as we’re concerned, there’s no such thing as a dumb question!
Ari Beser is the author of the book ‘The Nuclear Family‘ and director of the documentary ‘Hibakusha‘. He used his Fulbright-National Geographic Digital Storytelling Fellowship (2015-2016) to give voice to the hundreds of thousands of people directly affected by nuclear technology today. He is the grandson of Lt. Jacob Beser, the only U.S. serviceman aboard both B-29s that dropped atomic bombs on Japan during World War II.