Following a week of speculation that the Japanese government might expand the evacuation region in response to patchy, elevated levels of radiation in some neighborhoods, the government took action June 16. The designation of new hotspots is based on radiation surveys. This additional evacuation guidance is a new layer on top of the 20-km exclusion zone and the previously defined hotspot zones that covered specific communities. These new house-by-house hotspots exceed the 30 km shelter-in-place zone and are often clustered near pre-existing hotspot areas. More details here and here. It’s hard to imagine this new evacuation policy not further fraying existing communities.
Meanwhile the U.S. government is extending through August 15 the evacuation zone of 50 miles that it recommends for U.S. citizens. (Some have pointed out the unfortunate choice of date.)
Much attention has centered on children’s radiation exposure. 1700 children live in the 20-30 km zone surrounding Fukushima despite the Japanese government’s advisory that all children should leave this zone. Many communities are proactively cleaning their school grounds and parent groups as far away as Tokyo are organizing their own radiation measurements.
The Daily Yomiuri has an on-going series on the nuclear crisis where today they describe the impact of delays in releasing data. In one instance, a community near the plant was evacuated in the early hours of March 12 to a city that was predicted by the plume forecast system (SPEEDI) to be receiving high radiation. The mayor was not informed of the danger. “Although the system was supposed to be used to deal with a crisis, we weren’t fully prepared to actually use it.” said one senior education ministry official. “There were no ideas or discussions about if the [SPEEDI] data should be made public.”
The story also describes a chain-of-command structure where when radiation data began being released to the public there was no one available to evaluate or interpret the data from the government perspective. This lack of context fueled mistrust and alarm.
The “Report of Japanese Government to the IAEA Ministerial Conference on Nuclear Safety–The Accident at TEPCO’s Fukushima Nuclear Power Stations,” was issued June 7 and is a relatively candid assessment. Some salient “Lessons Learned” related to plume forecasts and crisis management are:
Enhancement of communication relevant to the accident: We will reinforce adequate provision of information on the accident status and response and appropriate explanation about the radiation effect to the residents in the vicinity. Also, we will keep in mind that the future outlook on risk factors is included in the information delivered while incidents are ongoing status.
Adequate identification and forecast of the effect of released radioactive materials: The Japanese Government will improve the instrumentation and facilities to ensure release source information can be securely obtained. Also, it will develop a plan to effectively utilize the system for Prediction of Environmental Emergency Dose Information ( SPEEDI) and other systems to address various emergency cases and disclose the data and results from SPEEDI, etc. from the beginning of these cases.
Highlights from the report can be found here; the full report can be found here.
Update: June 12 the NYT had a story of the evacuation incident…”If they had known earlier, they would have seen Speedi’s early projections that radiation from the Fukushima plant would be blown northwest…many of the residents around the plant who evacuated went north, on the assumption that winds blew south during winter in that area. That took them directly into the radioactive plume, he said — exposing them to the very radiation that they were fleeing.”
Upward revisions of the scale of the radiation damage continue to be released. Here is a summary of a few from the past several days.
Yesterday the Japanese government reported to the IAEA that reactors 1-3 all experienced a nuclear fuel “melt-through” in the hours and days after the tsunami on March 11. The condition is characterized as worse than a total core meltdown.
On June 6 Japan’s regulatory body, Nuclear and Industrial Safety Agency (NISA), revised upward its’ estimates of the total radiation released from the plant. Their new value (770,000 terabecquerels) is twice that of their previous assessment and falls more in line with the amount (630,000 terabecquerels) originally assumed by the Japan Cabinet Office’s Nuclear Safety Commission of Japan (NSC).
Japanese officials continue to come under attack for their failure to fully release data related to the radiation contamination – both radiation measurements and additional overlooked plume forecasts. The high radiation measured on the ground 30-50 km from the reactor site in the early stages of the crisis could have better informed safety measures. “Professor Yasuyuki Muramatsu of Gakushuin University says radioactive iodine has a high effect on children. He says that if the data had been released earlier, more measures could have been taken to protect them from exposure.” (Yesterday the government expressed regret for their failure to do so.)
The overlooked plume forecasts were several predictions for the Fukushima (Daiichi) reactors that have been the focus of the crisis, and also numerous predictions for the other Fukushima (Daini) site. The government had promised in May to release all plume forecasts and yesterday the Japanese science ministry apologized for the oversight.
In the U.S., several groups came together in late March to submit a Freedom of Information Act request to the U.S. Department of Energy and NRC to release all radiation measurements that might have informed the U.S. decision-making process: “’By recommending a 50-mile evacuation zone for U.S. residents, N.R.C. Chairman Jaczko gave a strong signal that the Fukushima accident was much worse than reported by the Japanese government and the utility,’ said Michael Mariotte, executive director of the Nuclear Information and Resource Service in Takoma Park, Md. ‘We believe that he was getting information about the severity of the accident from airborne radiation measurements taken by U.S. Department of Energy aircraft. But neither D.O.E. nor the N.R.C. has published those measurements in full.’ ”
One of the reasons given by the Japanese government for the delay in generating plume forecasts is that their model system, SPEEDI, was hardwired to receive radiation data at the Fukushima nuclear plant site. When the sensors failed in the massive power outage, the data link broke and the model was not able to run. This breathtakingly fragile modus operandi apparently required much effort to sever the close connection between the data ingestion and the model, and prevented a timely delivery of plume forecasts of where the radiation might drift. When they were finally able to do the simulations in a “stand-alone” mode of hypothetical estimated source terms, the government was so skeptical of the veracity of the results that they delayed releasing them widely. (More details on the release of plume forecasts by the Japanese government, chronologically: here, here and here.)
The Economist has an insightful piece that allows us to frame this failure of operational response in a larger context of brittle extensions of technology. Outreaches of technological prowess like complex power plants or challenging deep-sea drilling operations can fail catastrophically. What we have seen ensue is profound destruction and “there is no ameliorative technology on a par with that which has failed.”
“…situational awareness is invaluable. Steven Chu, America’s energy secretary, was reportedly shocked to find that the only source of information from the Deepwater Horizon’s blowout preventer was a single gauge. So he should have been. Sensor systems for getting information out of containment vessels, off sea floors and from all sorts of other out-of-the-way places should be deployed widely and in redundant ways. They should also be kept independent of the related systems used for control; you want them to work even if—especially if—the control system does not.”
Delays in assessing or predicting outcomes at the time of a catastrophe are avoidable. One way to ensure that enough redundant measures are in place is to have regulators evaluate “safety cases” that the industry games out and for which they demonstrate a response plan.
“Better still if the companies make not just a case for safety, but also a case for their ability to react when things do go wrong, and they find themselves in the uncharted space between the spines of well developed technology. It really does help to think about the unthinkable.”