We haven’t reported on the Fukushima nuclear disaster in a while, so it seems worth providing an update here. The short form? Plans to remove spent nuclear fuel have been delayed again, this time until fiscal year 2018 at the earliest; new fuel leaks continue to be discovered; cleanup cost estimates continue to rise; 300 tons of radioactive water are still pouring into the Pacific Ocean every day; and cleanup robots are still being destroyed by extremely high radiation levels.
With regard to spent nuclear fuel removal postponements, the most recent ones are reportedly because of “delays in preparation” relating to cleanup and decontamination efforts, according to the Nikkei business daily.
It should be remembered that the spent fuel from the No. 3 reactor was originally slated to be removed back in early 2015, before the plans were pushed back to fiscal year 2017 — and now until fiscal year 2018 “at the earliest.”
Reuters noted in recent coverage: “The report comes a few months after the Japanese government said in October the cost of cleaning up the Fukushima plant may rise to several billion dollars a year, adding that it would look into a possible separation of the nuclear business from the utility.”
With regard to cleanup robots being destroyed by extremely high radiation levels, that’s in reference to one recently being sent into the Unit 2 reactor for the first time (since the 2011 earthquake and tsunami). The radiation inside the reactor is still high enough that it destroyed the robot’s camera, apparently, after less than 2 hours.
The cleanup robot was apparently being exposed to an estimated 650 Sieverts per hour while in the reactor. For context, one Sievert of cumulative radiation exposure is the maximum lifetime limit for NASA astronauts, and short duration exposure to 4–5 Sieverts imparts a roughly 50% chance of dying within 30 days (often gruesomely). Higher doses will kill much faster. As an example, after being exposed to 36 Sieverts of radiation over a short period of time in 1958, Cecil Kelley died within 35 hours.
The Verge provides an interesting account of the situation:
“The robot was designed for up to 1,000 Sieverts of cumulative exposure. The AP reports that level of radiation would kill a human being instantly. After the cameras started malfunctioning, the team decided to pull the robot back from its mission before losing it entirely. Images captured from the chamber before the robot malfunctioned showed layers of melted paint, cable insulation, and metal grates.
“Tokyo Electric Power Company said the robot was deployed to observe and clear the passageway with a high-pressure water nozzle so the team could send another robot to assess the structural damage. Pulling the first robot early means the follow-up machine will have more work to do and less time to do it, since both robots were designed to withstand the same amount of radiation.”
As a final note on estimated cleanup costs, TEPCO’s estimates keep rising year after year, which makes one wonder if the original estimates (and the current ones) are nothing but fluff so as to avoid unnerving people.
And a final final note: estimated cleanup costs, and the general viability of the cleanup and containment effort itself, are predicated on the idea that there won’t be another major earthquake and/or tsunami that affects the area before the 2030s, when TEPCO estimates cleanup to conclude (2030s is very optimistic).
Maybe there won’t be. But what if there is? That scenario is a real possibility. Notably, there were actually internal warnings within TEPCO about the potentially devastating effect that a tsunami could have on the Fukushima plant all the way back in 2008, 3 years before the disaster occurred. These warnings went unheeded — nothing was apparently done on the matter despite the knowledge of the risk.
In related news, there was recently a fire and an explosion at one of EDF’s nuclear power plants in France. These events occurred outside of the nuclear zone at the plant, so there’s no danger to the general public according to the plant’s operators and experts. Interestingly, such events are “fairly common” according to those familiar with the regional industry. For more information, see: Explosion At Nuclear Power Plant In France Poses No Contamination Risk, Authorities Say.
For more information on the Fukushima Nuclear Disaster, see: