On Wednesday, June 1, 2001, I visited Nakate-san, the representative of “Fukushima Network for Saving Children from Radiation”, in Fukushima City to hand two Geiger counters (International Medcom CRM-100 and Inspector Alert) provided by Safecast. This article is about the trip.
2. On Shinkansen
I went to Fukushima by Shinkansen “Tsubasa” from Tokyo. I occasionally measured the radiation level inside the train car. At Utsunomiya Station while the train was stopped, I saw 0.12 micro Sv/h, but when approaching Koriyama, I saw 0.42 micro Sv/h, and at Koriyama Station while the train was stopped, I saw 0.56 micro Sv/h. Between Koriyama and Fukushima, it was 0.51 micro Sv/h.
Discovering that I could measure high radiation level even on board train that was running, I decided to measure more frequently on train on my way back. After I mapped the result of monitoring radiation levels in juvenile welfare institutions in Fukushima by the prefecture ( http://goo.gl/ln0xH ), I could infer that the areas with higher radiation levels than the lower limit of what we call radiation control area by Japanese laws have spread across the prefectural boarders, but since we do not have (or I thought we did not have) the similar data outside Fukushima Prefecture, I could not be certain of the extent. I figured that by measuring radiation levels while going south by Shinkansen, I could have a better understanding of the extent to which the radioactivities have spread (the result is shown in 5, Conclusions).
In Fukushima City, I have witnessed a number of surprising facts. The first surprise was that people wore normal clothes when they got off at Fukushima Station. Most of them did not wear facial masks. I was even more surprised to see a man with T-shirt and short pants. I wore a facial mask, a cap, a long-sleeve and smooth wearing so as to prevent radioactive materials to stick.
On the Shinkansen platform of Fukushima Station, I saw 0.58 micro Sv/h even though the platform is at a high location.
3. Measuring on Foot
I was a bit startled to detect a level of radiation comparable with those in radiation control areas, but after starting walking around the city, that sense soon got benumbed, because there was nowhere in the city, at least as far as I walked, where the radiation level was below 0.6 micro Sv/h (which approximates the level for radiation control areas defined by Japanese laws).
The temperature was a little lower than around Tokyo in Fukushima City, but I got soon accustomed with the chilliness. The rain began to fall, and I bought an umbrella at Seven-Eleven near the station. But most people I saw in the city, either walking or riding bicycles, did not use umbrellas or wear facial masks.
I found a group of people, probably college students and their lecturer, moving with heavy weights and goggles. One of them was on a wheelchair. It was perhaps a class to experience the daily life of elderly people. In fact, people in Fukushima City in many respect were spending their daily lives, whether they liked it or not.
At a bus stop on the side of an elementary-school ground, I saw 2.36 micro Sv/h on my Geiger counter. Luckily, at least on that day, no one was in the ground. Usually, I publish my reading on radiation photo map calculated from an average of counts in about 90 seconds. But since precision of lower digits is not that meaningful with this large value, and because each detection of radiation consumes power, I decided that about 30 seconds should be OK.
I saw 2.31 micro Sv/h at the flower garden in front of the gate of a high school. Soil without any efforts of maintenance, I think, tends to make radioactivity stay, and vegetables do absorb radioactivity. Which, I imagine, makes flower gardens and plantings sources of higher radiation levels. But concrete surfaces may also tend to stick fast to radioactive materials, according to findings by Safecast and other measurements.
One of the most surprising events in my trip was that a high school girl was reading something looked like a textbook sitting on a bench near the school without any sort of protection from radiation or the rain. Since I saw the reading on the Geiger counter, it looked to me as if she was there with some sort of tragic resolution. But perhaps the truth was that she simply did not know. After I told her that the place had high level of radiation, she left. (It could be because she thought that she was talked to by a strange middle-aged man.)
Near the location, there is an elementary school that is attached to a university. The school boys on their way home were playing, wearing short pants. There could be less radioactive materials in the air because of the rain. But it was certain that they were on the ground. I did not know what to do watching children walking and running with their legs exposed while the radiation level in the air was 1.62 micro Sv/h at that time.
I continued my measurements especially near schools I found on the map in my iPhone, walking down south and crossing a bridge. I was heading at NPO IL Center Fukushima where Nakate-san work.
The photograph on left is one I took on my way back after meeting Nakate-san. I saw 2.91 micro Sv/h, which was the highest record in the trip. It was measured at 1m high from the ground, suggesting that even higher values could be measured at lower height, and probably across Fukushima City.
I wrapped my Monitor 4 with vinyl in order to protect the counter from dusts, which turned out to be a good protection from the rain, which suggests that there was no influence of alpha. But some beta may have influenced the readings. If you are concerned, please think in terms of CPM instead of Sv/h. Since Monitor 4 is calibrated to gamma rays from Cesium 137 so that 100CPM nearly equals 1 micro Sv/h (with error of plus-minus 15%), you can figure that, for example, 2.91 micro Sv/h means 291CPM or so. Imagine that this means 4.85 counts per second. Still, the Geiger tube of Monitor 4 is not so sensitive.
The photograph on right has been the most controversial among the ones I have published in the album of “Save Children of Fukushima” Facebook page. I saw 1.62 micro Sv/h at the side of a high school ground, where the baseball club was practicing in the rain (the radiation level could be higher on the ground itself). I felt as if something was breaking in my mind when I saw this.
What can we do? I think that what we adults can do is to let those high school students play baseball they love as long as they want in a safe, distant place. The next question is how we can achieve it and what each of us can do to assist that.
A map has been generated to plot the measurements I took on foot ( viewable from http://goo.gl/y9PwU ) as shown below.
The red marble indicates where the radiation levels were especially high, being equal to 2.0 micro Sv/h or higher. Although nothing definitive can be said with this small number of samples, the distribution of red marbles seems to have some geographical characteristics. So I made it to show terrains as well.
This is nothing more than a hunch, but hot spots may spread on the foot of mountains (of course, the whole Fukushima City is a hot spot, but those hot spots are where special attentions are required). Perhaps we should check the foot of mountains next time.
4. Talking with Nakate-san
I met Nakate-san, the representative of “Fukushima Network for Saving Children from Radiation”, at NPO IL Center Fukushima.
Nakate-san seemed happy to receive an Inspector Alert, a handheld surface contamination meter. He told me that “Fukushima Network for Saving Children from Radiation” has already had some of these units, but certainly would like to use more of them. When I told him that Safecast would be happy to hand more sensors if people would share the measurements with public, he told me that he liked the idea of encouraging people to measure radiation to help others receiving sensors, because that would fit the current trend in Fukushima for mutual aids.
In Fukushima City, Nakate-san told me, radiation levels higher than 0.6 micro Sv/h can be observed even inside houses, if, for example, the house is wooden. Lots of people want Geiger counters to decide whether they should evacuate their houses by measuring the surrounding radiation levels. I felt once again that it is urgent to deliver as many sensors as possible in such an area.
Nakate-san cited someone’s saying “It’s not only fuel rods that have been exposed by the nuclear power plant accident. The problems and virtues we have had in Japan have also been exposed.” Describing the activities of “Fukushima Network for Saving Children from Radiation”, he said he did not want to easily use the words like “bonds”, but he admitted that it had been goodness in people’s minds and bonds among them, which have been exposed as actions
“People have always been willing to protect their children. But did not act that way from time to time, while they were living ordinary lives,” said Nakate-san. “But they have changed themselves through the incident. They have made actions.”
He told me that Fukushima people have had this tendency to be tolerant, especially in Naka-dori, part of Fukushima Prefecture where Fukushima City and Koriyama City are situated. They had avoided fighting over “trivial” problems… “But this time, it was different,” he said. “They have suddenly started to act and to speak at once. They are now eager to cooperate and to do things together.”
He told me that activities of “Fukushima Network for Saving Children” are region-based. They are helping people to evacuate, to clean up radioactive materials and to measure radiation levels. He emphasized that knowledge is important to protect our children. Therefore sharing knowledge is also an important part of the activities of the network. Currently, the network is using a room in Nakate-san’s house as the office, which was dedicated to his children who are now living with his wife in the west of Japan.
“What makes the situation different from Chernobyl,” Nakate-san said, “is first of all the Internet. Through the Internet, we can access information. We can read articles of foreign media such as New York Times. No one can hide information any longer. Secondly, the NPO activities, which have risen after Hanshin-Awaji Earthquake. Those have empowered us to do this kind of activities.”
I thanked Nakate-san, being a researcher of the Internet for a long time.
On my way back to the station, I passed many people on their way home from work or children going to “juku” (exam-preparation schools), which looked like an ordinary scene at dusk in Japan. Without knowing about the radiation levels here, no one would think that this place has a too big problem to live. Of course, there are people evacuating or helping others to evacuate such as “Fukushima Network for Saving Children”. But what about the rest of them? How do they feel to be there?
This was a too short stay to suppose what were going on their hearts.
In the Shinkansen on my way back to Tokyo, I continuously measured the radiation levels inside the train in order to have a general idea of the southern extent of high radiation areas that include most of Naka-dori district. Below is the resulted map (viewable from http://goo.gl/AOxSv ).
This is just an approximation, as the measurements were taken while the train was rapidly moving, suggesting that each marble represents gamma rays from a wide area, and the counts drastically decreased inside tunnels (the fact that radiation level decreased inside tunnels suggests that the source of radiation was outside, not inside of the train).
This is nothing but a guess, but the high radiation area seemed to extend as far as Okawara City, Tochigi Prefecture, southward (later, this was confirmed by the map created by Prof. Hayakawa of Gunma University).
6. Later in Fukushima City…
The two Geiger counters Safecast provided were put into the test run just two days later. I do not know if they have been successful in sharing and publicizing the sensor readings, but if they have not, I think that we have to question once again, as a design problem, how we can make it easier to share and publicize sensor readings for those people worried daily by radiations and occupied with their struggles of providing safer places for their children or evacuating from where they live.
Day after day, questions have been posted at the mailing list of “Fukushima Network for Saving Children” with respect to the means and conditions for evacuation. Just the other day, consultation on children’s health was provided by a group of doctors visiting Fukushima City. However, those high school students who have been spending their after school outdoors practicing their athletic skills were not present.
Talking about high school students, yet another issue has risen in Fukushima. “Fukushima So-Bun”, the 35th All Japan High School Cultural Festival, which had been investigated whether it was appropriate to be held after the earthquake and nuclear power plant accident, was decided to be held in locations both inside and outside the prefecture for five days from August 3. The venues include those high radiation areas such as Fukushima and Koriyama cities. In this event, more than 6,000 high school students all around Japan will gather in Fukushima Prefecture. I feel as if our knowledge and preparedness are tried in the question whether we can protect the safety of those high school students visiting Fukushima while both aftershocks of the earthquake and the nuclear power plant accident are far from being close to conclusions today.