How I spent my Sunday in Fukushima


The Safecasting drives officially started after my last trip to Japan, so I’ve been watching from afar as Pieter and an ever growing volunteer team of total heros have set out time and time again to try and map the radiation levels in the areas surrounding the Fukushima plant, as well as the rest of Japan. Knowing that I was going to be back in Tokyo for a number of Safecast meetings and the Radiation Seminar at the same time that Miles O’Brien and Xeni Jardin were going to be working on a story for PBS News Hour that had some focus on Safecast, organizing a drive seemed like an obvious option.

Me, @xenijardin & @noktonlux heading to Fukushima. #safecast

This morning Pieter, Xeni and I (pictured above) set out with Miles, along with father/son superteam Joe and Bryan Moross. The plan was to drop off a few Geiger counters with volunteers and try to cover some some new ground, perhaps near the exclusion zone. But it ended up being so much more.

Miles O'Brien

(While Miles and Xeni were filming throughout, those bits were for PBS and will certainly be available sometime in the future, so this account is mostly my own observations, unless noted all photos are also by me.)

The day began in Shinjuku around close to 7:30am when we picked up a rental car, this was a large group with a lot of gear so we had a need for two vehicles and the usual Safecast car on it’s own wasn’t quite enough. We wasted no time and started driving north. Depending on where you are in the city, background radiation levels in Tokyo hover right around 50 CPM which is only slightly higher than what we believe they were prior to 3/11 though we weren’t measuring things then so can’t be positive. For our purposes we are assuming the average around the country was 35 CPM which is worth noting before I start mentioning numbers going forward. It wasn’t too long in our trip before we hit our first hotspot in Nasu.


Elevated readings

This way to Fukushima

Our first stop was Nihonmatsu which is not too far from Koriyama to meet up with some volunteers in the area and hand out a few new sensors for them to take measurements with. We met at restaurant and of course started measuring things the moment we set foot in the parking lot. Levels were noticeably higher than we’d seen just a few hours prior in Tokyo.

Over 300 CPM air contamination here

Close to 3000 CPM surface contamination

Another bit worth noting here in case you haven’t been following along with the work Safecast has been doing so far, surface contamination is much higher than air contamination. There are two main reasons for this – “Fallout” literally means this radioactive crap fell out of the sky and found it’s new home on the ground, and much of contents of said crap are beta emitters. Beta radiation is lower energy than gamma so you need to get close to it to measure it – which in this case is the ground. If you only measure the air you miss the betas all together. Anyway. Surface is higher than air, and around 3000 CPM on the ground in the parking lot here is 10X the air levels.

As occasionally happens when we are measuring out in public, people approach us to find out what we’re doing.

JAM asking

Speaking with residents who are very stressed out because they haven't been able to get any info from the govt

People are curious, and often they are concerned.

Hiroko Ouchi was both. On top of that she was upset.

She said that she hasn’t been able to get any information about the levels around them, the levels they are living in from the government or TEPCO. She said at first she wasn’t concerned because residents were told everything was fine and not to worry, but over time people started taking readings on their own and hearing about readings taken by others that suggested things weren’t all fine and this really stressed her out. This area is far enough away from the plant that no one is being officially evacuated, which means anyone who wants to leave has to do it on their own and pay for it themselves. This has caused a lot of trauma in the community as some people leave and some people stay. Ouchi-san said it is very upsetting for people to be in this position and have their questions go unanswered.

Discussions with locals

Concerned folks

Miles filming the conversation for PBS

Ouchi-san went on to say that she’s most worried about the younger people and children who might not have the means to move away, as they are the ones who could suffer most in the long term from exposure to this radiation. She was excited to learn about the mapping that Safecast was doing and took our cards so she could see the site and maps when she got home. Before leaving she thanked us repeatedly and expressed sincere gratitude for our efforts, and again extreme disappointment that the government hasn’t done the same.

This was a totally unexpected event but helped put us in the mood for the rest of the day. Before heading out we have new Safecast volunteer Washiyama-san a brand new bGeigie so he can help map the area street by street. If all goes well we’ll get him several more devices in the coming weeks for his whole team to put to good use and then send the data back to us.

Washiyama-san, safecast volunteer

Once back in the car we decided to head east and see how close we could get to the exclusion zone. We watched the readings rise and fall, though generally increase on the whole the further we went. We have a device outside of the car, and several inside taking readings. At many points we would see a 25% increase depending on which side of the car we pointed a device towards. Very quick changes in very small areas here. At one point things seemed to be increasing very rapidly and at much higher jumps than we’d seen previously. We were so distracted by the drastic readings that we almost ran right into a roadblock staffed by several police officers who were standing around in the street.

We turned past them and drove down the road a short ways and then stopped to look at our devices which were completely blowing up.

Approx 16,000 CPM surface here

On my last transatlantic flight I measured over 800 CPM on the flight. Seeing over 1000 CPM in the car was a bit shocking, opening the door and putting the device on the ground in the middle of the street and seeing it climb, in a matter of seconds, to almost 16,000 CPM was, well, I still don’t even know how to describe it. I was completely taken aback by this. We were maybe one city block from where the officers were standing – outside and unprotected and decided we needed to go back and talk to them.

Officer at roadblock at 20km line

Speaking with the officers

The officers were very polite and happy to talk to us. We asked them if they were concerned that they were standing outside all day with no protective gear and they told us their bosses have assured them it is perfectly safe and so they have to trust them. We told them about the readings we’d taken just steps from where they were and offered to show them personally that the levels were incredibly high – they declined saying they needed to trust the authorities. Which was weird, because to most people – they are the authorities. We measure radiation all the time, and were noticeably shaken after seeing the readings we just had, and these guys were being told there was nothing to worry about. Suddenly some sort of commanding officer arrived and told us we had to leave and everyone stopped talking to us. Like turning off a switch.

We got back in the car and drove about 1km away the other direction away from the roadblock.

Road closed 1km ahead

There was a small restaurant that was closed up and seemed like a good place to stop, take some measurements and talk about what had just happened. This was the first time I realized there wasn’t anyone else around really. All the buildings I could see were closed up, no cars, no lights, no one home. From the look of the weeds and growth, they had been gone for quite some time.

This restaurant had signs taped in the window saying basically “Sorry we are closed for an undetermined period of time. Will try to reopen in the spring.”

Unfortunately I think that’s being a bit optimistic.

Sorry we're closed

Overgrown. Abandoned.


It was here that we took our highest and most concerning readings of the day. The parking lot of the restaurant was active, but less than we’d just seen. But when we walked across the street – maybe 10 feet away, we measured over 20,000 CPM and 9 µSv/hr. We pulled out our SAM 940 to try and identify the isotopes and found things we weren’t expecting at all. So we grabbed some samples to send to a lab for professional analysis and got out of there quick.

We drove for a little ways until we found an area with fairly low levels where we felt safe stopping to film a few interviews for the PBS piece. This was a good 10-15 minutes away from the barricade we’d just encountered and the area was still a ghost town. No one anywhere. With the exception of the sound of a nearby stream, complete silence. Until a police officer rolled up.

Officer: "you aren't from around here are you..."

He started off with the Japanese variation of “You folks aren’t from around here are you…” He was friendly and once convinced we weren’t looters left us on our own. Over the hour or so that we were in the area we saw a police car every 10 minutes or so, at least, but no other people. This was pretty striking, I’d prepared myrself for what I thought I was going to see, but sometimes it’s what you don’t see that gets to you.

Empty streets

Vacant houses

This stream was the only thing we could hear.

Nobody's home

Taped shut

Looters beware

While the people had clearly packed up and moved out, that didn’t seem to translate to the animals. First of all there were giant wasps dive bombing us all day. Luckily no one got stung, but seriously these things had to be close to 3″ in length. Much less scary but more heartbreaking was the pets that had for one reason or another been left behind. We several dogs, with collars and a cat who hung around us. All of them looked fairly skinny despite that there seemed to be several bowls of food left around for there. All the animals seemed a bit nervous and cautious, some came closer than others, all left pretty quickly. Almost as if they were looking for something, or someone. There was also a sign with photos of dogs that had been found and rescued – hoping their owners would claim them. That sign was from May 1st, and hadn’t been updated so no idea what happened next.

Scaredy cat


Rescued pets

Not forgotten

Abandoned pets

As we were starting to wrap up a car drove by and came to a quick stop. Two gentlemen got out, one of them was a reporter for Asahi TV and the other was Tadao Mumakata, a resident of Koroyama who is working on a way to produce geiger counters locally. They knew about Safecast and were excited to run into us. We talked for a while and then decided to go get some food before heading back to Tokyo.

We stopped at a smallish family restaurant and talked about our plans and goals, geiger counts and what we’d learned – hoping to pass some of this on and hopefully help someone skip over some of the early mistakes we’d made ourselves. They were happy for the info and we exchanged contacts for further discussion.

Tadao Mumakata (@telejapan)

(Above photo, with me in it talking to Mumakata-san taken by Xeni)

We bowed, shook hands, and went our separate ways. Back to Koriyama for them, and back to Tokyo for us. Our drive was going to take a few hours longer. Finally around 2:30 am we made it back and started dropping people off at their respective houses/hotels. But no spare moment could be wasted. At the final stop we uploaded the log files from the bGeigie – the geiger counter we had mounted outside of the car all day logging radiation and mapping it against GPS points. This produces a map of the whole drive, and dumps the data into our full database, filling in a few more pieces of the big picture.

And it really is a big picture. These places have never had the kinds of detailed measurements we’re taking, and the measurements that have happened haven’t been shared openly with the residents – who without question are the ones who need to have that info the most. I’ve known this since we started the project but seeing it first hand today and hearing people thank us for trying and for caring was heavy. This project is important and I’m so honored to be a part of it, and so glad to have others involved who have done the impossible to get us this far already.

(photo by Pieter Franken)

I was back in my hotel room by 3am, and I’ve spent the last 3 hours putting this report together while it was all still fresh in my mind. I have a flight to Los Angeles in a few hours, so now it’s time to sleep. As much as it’s annoying to end this on a begging note, driving two cars (granted we usually only need one) around Fukushima all day, including gas and tolls clocks in at just shy of $500. We’ve got a paypal donate button on the top right hand side of this page. If you wanted to throw $5 or $10 our way it would help us chip away at that and help fuel the next one.

39 Comments on “How I spent my Sunday in Fukushima

  1. Well done, I too am from Tokyo (Shinjuku) and chose to leave at 8months pregnant and with our 2 cats. However, hubby and dear friends are still working away.
    Please contact Japan cat network ( my friends David/Susan) and /or JEARS (Japan earthquake animal rescue) on FB as they are doing great work in that evacuated area and perhaps would be interested in a collaborative effort to get data and ensure animal safety.
    Thanks for the great work your team is doing despite the lack of info for radiation levels via the govt. I just want to make sure it is safe for our baby and 2 cats to return.

    • Comment to Cher Mori,

      Reading “…I too am from Tokyo (Shinjuku) and chose to leave at 8months pregnant…” I got the impression that you are leaving due to radiation levels in Tokyo. Here is just some information you might be interested in.
      During a long distance flight from Japan to Europe or the US one get typically a dose of 200 micro Sievert. The radiation level in Tokyo varies naturally between 0.08 and 0.13 microSv/h. (Data are measured daily by myself and people I know). For the sake of a simple calculation let’s say the level is 0.1 microSv/h. This means the flight gives you a dose, which is equivalent to a stay of 2000 hr or roughly 83 days in Tokyo. I don’t know where you will go to and I don’t know what the natural radiation level there is, but you need to consider this as well.

      All the best to you and your baby!

  2. Thank you for doing this, and for bringing more awareness and certainty to the people. Some have hard decisions to make, indeed.

    Here a few additional sources, maybe you know already, that may hint at what background radiation to expect where. Ground contamination is another matter.

    Radiation contour map by Yukio Hayakawa (Gunma Univ.)

    Radiation dose measurements by MEXT and local governments at 1 or 0.5 meter height. Interactive map

    Differences among readings are an unnecessary source of mistrust, debate and sometimes public hysteria. As you point out, there are local hotspots, where a few dozen meters make a large difference.

    My understanding of the main sources of differing measurement results is:

    Place (height above ground, soil condition on location, near or in buildings, differing natural background radiation)

    Equipment (energy range, size of sensor, type of sensor, averaging algorithm)

    Method (time interval, for long-term trend or for short-term peaks)

    Common radiation equipment manuals specify measurement uncertainty around plus-minus 20%-30%. People who are questioning official measurements for being 2x or 3x lower than what others measure can relax. Where a factor of 100 or 000 can be expected to affect health long-term, we do not need to discuss such minor variations.

    • Dear CoCreatr,

      Your comments on the measuring error are very good and people need to consider this before drawing wrong conclusions.

      As you mentioned the Radiation Conture Map by Y. Hayakawa let me add 2 comments:
      1 – I use this map often for reference purposes it is the best I found so far
      2 – the maxium value of > 8 microSv/H is not very good. Such a dose rate results in an annual dose of “only” 70milliSv/a, which is actually not that high. It would be more important to see also areas of 10, 12, 14, 16, … microSv/h. For comparison on the annual dose: Germany: average dose per year (natural and artifical radiation) is 4milliSv/a; people exposed to professionally to radiation have a limit of 50milliSv/a. Japan: old value 100mSv/a for workers at TEPCO’s NPP and now 250 milliSv/a.
      250 milliSv/a is in Germany regarded as a level that “damages can occur”. Poor guys who have to work in Fukushima to clean up the mess the management – not the tsumani – created…

  3. Thank you so very much for posting this information. It does help get the word out, and knowledge is, indeed, power.

  4. Hi, I just wanted to say you guys are doing a fantastic job. I live in Kashiwa and it was one of the places that was hit by the fallout on March 21st as seen on this web page from the Cancer Research Center located here in Kashiwa,
    I even made a video of my own a few months ago and posted it on youtube, I have since gone around and taken soil samples and paid to have them professionally tested, unfortunately the only services offered that I could find were either testing for CPM or the levels of iodine-131 and cesium-137 and 134 only. One of the samples I had tested was so radioactive that the laboratory informed me that they “can NOT dispose of or contain” it and they had no choice but to mail it back to me! Its still sitting in the unopened box in my garage. I have been looking in to purchasing a CoMo-170 or some other professional device to properly test with. If you guys ever come over to Kashiwa let me know, as I am always available 24/7.

    • Your video at YouTube demostrates nicely the effect of rain water, which accumulates radioactive particles. What you measure there is quite a high level of radiation.

      Concerning contamination measurements it is sufficient to measure Cs137 as this is the largest part of the contamination. I131 is almost gone because the half-time is only about 8 days.

      The CoMo-170 looks pretty good for surface contamination measurements.

  5. Good report, it concurs with what I found in April and May. I could have given you much of this data back in April as I’ve been in and around the exclusion zone many times with Geiger counters on animal rescue. Try route 399 – that was where I had the highest readings. I have a 4WD van and know the area if you need someone to take you up there.

  6. Will you be supporting safecast drives along the US west coast? While the degree of contamination is obvously not as extreme as Japan, the pacific northwest did get hit pretty hard with contaminated rain this spring. Hawaii seems to show slightly increased levels along the flanks of its mountains. It would be interesting to see if there is a similar result along the Oregon or Washington coast or in the cascades. At the very least, it would establish a baseline in case of a repeat experience (heaven forbid) at some point in the future. I would be willing to do a few of these drives when you can free up a bgeiger. I live in the PDX area, so it would be easy to connect with you. Please let me know of your interest (or lack thereof) in doing this.

    Keep up the great work. This is a terrific service! I look forward to seeing roll out of the other serivces you are planning.


    • I would not expect much influence of Fukushima to the natural radiation at the West Coast. Before you start measuring I recommend to get the radiation data for the area before Fukushima happend. Otherwise you might measure a lot of data with not much information into it except that you can say you do not see any influence from Fukushima. Make also sure that your measuring devices has an error below far below + – 10 % – these are the more expansive ones.

    • No – note the “u” is a replacement for “micro”. It’s about a million times less than a “lethal” dose.
      Not a good environment to stay in, regardless.

  7. Good on you guys!
    Have donated $10 because it’s you,me and the common people that will be the ones
    to start to make the real changes that this world is crying out for.
    Those in charge… forget it,their day is done.
    Good luck to everyone in these “interesting times”.
    The roller coaster ride has just really begun.

  8. Once there is a permanent terrain contamination of this degree, it is unlikely people will be returning in a few months’ time. Thanks for showing how bad it really is. The Inspector monitors read about three times higher than most other geiger counters and that has to be factored into what they are saying is normal background, or into any other numbers that come up. In any case the picture in Japan for the future is extremely grim. If people only realized that New York and Paris will go the same way when their crappy reactors blow, they would demand the whole industry be buried underground starting with putting Daiichi under a big mountain of sand. Entombment is the only way to stop this kind of radiation from spreading throughout Honshu. Without unanimity in demanding entombment there can be no action to stop the releases. Without understanding that entombment is critical there can be no solution to the grave dilemma facing Japan.

  9. I’m surprised you weren’t wearing more protective gear and masks??.. Those readings are staggering!!
    Thanks for the investigation!! p.s. The Japanese people seem lovely–I hope they can take heed!!

    So, all Pacific flights now are contaminated up to 800 CPM?? The Jet Stream is a mess!!!

    • I just want to add that I’m saying prayers for the Japanese (pets, too)!….I guess we all need it, frankly.

  10. I’ve been Following Xeni Jardin’s postings on Google+, and this posting just blows away anything I’ve seen so far on the Fukushima area reporting! “Great job!” doesn’t do it justice…will post this on other sites to let others know….hope the animals eventually get rescued! Take Care Everybody! So, I wonder what those Police guys are now thinking…..

  11. I have to say that your black and white photo of the young police officer assigned outdoors with only a thin paper mask is an exact deja vu flashback to scenes from Chernobyl, where many young officials wore the same masks and similar uniforms!!… Unfortunately, the man who took that stunning footage at that time later died within weeks after filming on top of the Chernobyl reactor roof work site (lethal radiation levels for all). He was the only brave person to document the scene…The footage was spectacular. The Russians were incredibly industrious and courageous under deadly conditions. I have never seen men work harder or more urgently. They were like Olympic atheletes…And it paid off!!!

    Thanks again for documenting history & take care!

  12. Thanks for your amazing work guys… respect.
    It’s as if the world population is splitting in two: one part does NOT want to know anymore…

  13. Ummmmmm……. they just drove through an area that just suffered one of the greatest earthquakes know to hit a populated area, ahhhh…… Sorry but where is the damage? If a 9+ quake had hit this are there would be nothing short of highly reinforced concrete structures standing.

    What do you think?

    • It was pretty widely reported that there was very little damage from the earthquake. Japan has incredibly high building standards. The majority of the damage came from the tsunami along costal areas.

  14. Just donated 10 dollars – though the work you are doing is priceless. Thanks for caring.

  15. Great work and history! It is really amazing what you are doing guys, thanks for your work. You are helping the people a lot.
    I don’t know what’s wrong whit the Japanese government, they are always playing down the situation an still saying that it is safe, that food and water are safe. They are even planning to get back all the people from the shelters to their homes as soon as possible. I really don’t understand the government; Prypiat, the nearest city to Chernobyl Nuclear Power Plant, is a ghost town, because it is still contaminated and dangerous. High radiation levels are still detected. They will also need to take special care of these little pets around there, since they are probably contaminated. The are eating just the things they find in the contaminated soil.

    Thanks again for your work, it is impressive.

    Regards from Ishikawa, Japan

    • as Bevan, just want to add, I’m also saying prayers for the whole country, the situation is very sad.

  16. I have some questions about the radiation level you show in the pictures.

    I went to Minamisouma at the end of may (this year) and we we stayed in a family’s house (one of the house which wasn’t “deleted” by the tsunami).

    We brought a geiger counter too but we couldn’t get the same levels as you got.

    Can you explain me if that levels are microsievers or milisieverts?

    We got 0.06 in Minamisouma (20km from fukushima nuclear plant) and 1.20 in Iidate (it was the highest radiation level we could check in all our travel there).

    We didn’t see any people using mask there (and that place is 20 km from Fukushima nuclear plant).

    About the people there…It’s really difficult to understand what there’s happening there, even all of us understand japanese and we could have a good communication, i felt like there are information which both parts (fukushima people and government) are hiding…

    We can’t exchange information, pictures or whatever (if you want), because I’ve been talking with many people before and after we went there, and all people have the same feeling…that’s weird.

    And yeah, the government is doing nothing..lying all time, i saw all the news in the japanese tv since the earthquake happened until now, and we were doing notice how the government has been apologizing because almost they said was an amount of lies, one by one.

    • Depending on the Geiger counter you had it may have only been reading Gamma radiation. Our devices detect Alpha, Beta and Gamma and we’re finding significant Beta contamination in these locations.

      • Yeah, that could be possible, but so far as I know, almost all the Geiger counters read at least beta and gamma, and those tubes with the special mica window can read alpha. Maybe if you give information about the Geiger counter you were using Debitto, we could know. Also it may depend if it was calibrated, but even if it wasn’t, the results are very different.

        • First to Debitto’s statement “We got 0.06 in Minamisouma (20km from fukushima nuclear plant) and 1.20 in Iidate (it was the highest radiation level we could check in all our travel there).”
          You are not showing the units you measured but only the figures. A figure without a unit has no meaning because it cannot be compared with any other values.
          As the figures are 0.06 and 1.2 and you were in an area, which should have a heavier contamination I assume that you dosimeter showed uSv/h (micro Sievert per hour). However, then the value of 0.06 appears to be very low. This gives me the idea that you switched on your dosimeter and started reading the first figures appearing on the display. All dosimeter need to average over a certain time (typically 1 min). This means you need to keep you dosimeter ON for at least one minute or the time indicated in the manual to able to get real values.

          Second to seans comments on alpha, beta and gamma detection.
          Measuring gamma rays is sufficient as you measure about 95% of all radiation. alpha particles are not emitted from Cs137, which is the bulk of radioactive isotopes from Fukushima. I actually wonder if you really detect beta radiation or only a higher accumulation of Cs137 and only see the gamma radiation. It would be interesting to know how you differentiate between gamma and beta radiation. May be you can comment on this.
          Identifying alpha particles are extremly tricky due to the short range even in air.

  17. Thanks for what you’re doing. It’s good to get an independent opinion & views. I have a Terra geiger counter and currently live in Chiba & Shizuoka. I will contact you to see if I can help in any way.

  18. Hi,
    First time visitor. but will keep on reading.
    As a physicist, the following paragraph seemed to necessitate some precisions.
    You wrote:
    “Another bit worth noting here in case you haven’t been following along with the work Safecast has been doing so far, surface contamination is much higher than air contamination. There are two main reasons for this – “Fallout” literally means this radioactive crap fell out of the sky and found it’s new home on the ground, and much of contents of said crap are beta emitters. Beta radiation is lower energy than gamma so you need to get close to it to measure it – which in this case is the ground. If you only measure the air you miss the betas all together. Anyway. Surface is higher than air, and around 3000 CPM on the ground in the parking lot here is 10X the air levels.”
    There is some confusions in the explanations here. Gamma radiations are made of photons, beta of electrons. Radiation of charged particles is considered to be interacting continuously with matter through the Coulomb force. This leads to a loss of energy through ionizations and excitations across the entire trajectory of the radiation. In contrast to charged particles, photons can travel random and highly variable distances inside matter before undergoing an interaction. Electron-matter interactions consist mainly of collisions between particles having the same mass. The difference of range between gamma and beta is not because of energy, but because of different interaction process. What you also notice when measuring close to the floor is the dose rate dependence on the distance. If you measure a point-source, the dose rate will decrease with the square of the distance when moving away from the source.
    Confusion is also coming from using the expression “air contamination”. It is not the contamination of the air that is measured by your Geiger-Mueller counter, but the dose rate of the activity deposited around. In other word the radiation field coming from radionuclide on the ground measured at a certain distance. It is better to use the term dose rate for a value of Sv/h and surface contamination for a value of Bq/cm2. Most of the time dose rates are measured with Geiger Counters and surface contaminations with proportional counters.
    It would be interesting to have surface contamination values, because it is what could be used to evaluate the ingested activity the people will suffer. Radioactive intake might then help evaluate the committed effective dose of the population.

    Hope I could help a bit.

    • CJBJ – a great explanation. You must be a physicist or a similar exotic “animal”. Like me!

  19. Keep up the good work! One small suggestion is that the list of drives should have the date of each drive on the page, since the data can take quite a long time to load on slower computers.

  20. CJBJ, what would you conclude from the data? An increase in readings can be expected due to the circumstances, but where is the line drawn between critical and acceptable?