GOVERNMENT MONITORING POSTS
[Part 1 here] In recent months there has been a fair amount of controversy concerning the accuracy of the radiation monitoring posts the government has installed all over Fukushima prefecture, and in some neighboring prefectures as well. We wrote about it back in July, 2012:
almost 700 of these monitoring posts (675 at latest count), which we refer to as “droids” because of how they look (see photo above). They are all powered by solar panels and use storage batteries.
[Update: 2700 monitoring posts have been installed as of Feb. 2013]
Through the Ministry of Education, Culture, Sports, Science, and Technology (MEXT), the government spent a lot of money (we haven’t been able to find out precisely how much) to have them installed, and spent more money to have a web site made that displays the readings: MEXT realtime environmental radiation page
From this reasonably attractive-looking page, users are supposed to click on a prefecture, then on a region of the prefecture, and then choose from any one of a dozen or more municipalities. Then a scrolling list appears on the right hand side, and users can select a particular monitoring post to review (In the case of Koriyama City in Fukushima, there are 393 monitoring posts in the list). A zoomable, scrollable Google Fusion map appears, and the individual posts are marked by colored dots. Clicking a dot gives the current reading at that location, updated very 10 minutes it seems, and it is possible to download data for the entire month. So, thank you for doing that much, at least, MEXT.
This system sucks in many ways. While working with it in order to compare the MEXT readings with our own, we’ve found that it’s impossible to get an overview of more than a small part of Fukushima at any one time, that hunting down particular locations is incredibly time consuming and frustrating, that the cumulative time data does not go back far enough, and that the downloadable data comes with many restrictions and is difficult to pull down efficiently. Yes, MEXT made this system ADAP — As Difficult As Possible.
We were alerted to possible problems with the construction and siting of the monitoring posts themselves back when we made the first blog post about them. At the time, a number of journalists and professors noted that the readings at the posts themselves were often noticeably lower than those of the surrounding areas, and that the ground around the posts seems to have been decontaminated or resurfaced in many cases.
A group called Association for Citizens Concerned about Internal Radiation Exposures (ACSIR) investigated further, and publicized its findings in October:
ACSIR page (Japanese)
Asahi Shimbun article about ACSIR’s findings
They claim to have detected a 10-30% disparity in readings close to the monitoring posts, and they suggested that shielding from the monitoring posts themselves was a potential factor. They did not provide their raw data, however, but only graphs and calculations. They accused the government of intentionally skewing the readings.
Greenpeace, which has been doing periodic radiation surveys, also checked the accuracy of the droids, and concluded that many of them were inaccurate:
Their method seems to have been fairly systematic, to take readings with a reliable gamma spectrometer (Georadis RT-30) very close to the droid, at 1m, 0.5 m, and 0.1 m heights, and also at 5m, 10m, and often 15 or 20m distance in one or more directions. They checked 40 monitoring posts in all, in Fukushima City.
Greenpeace stated, “For 75% of them, the radiation readings close to the posts were lower than readings for their immediate surroundings. Contamination levels within 25 metres of the posts were up to six times higher than at the posts themselves.”
Looking at the Greenpeace spreadsheet, however, it becomes clear that the monitoring posts themselves generally read higher than Greenpeace’s instruments do right next to the posts at 1m height. So that’s not the problem. The problem is that the readings at the posts often don’t represent the contamination of the surrounding area very well, sometimes understating it by half or more. As we’ll discuss further, if a monitoring sample is intended to represent an average of a particular area, we actually should find find areas of higher radiation somewhere nearby, but we should find areas of lower radiation as well. Otherwise we can deduce that the monitoring post was placed in a particularly high (or low) spot. But the only way to really know is to take readings systematically in several directions all around the monitoring post. From the Greenpeace spreadsheet linked above it appears that they were able to do that in only a few cases, finding results that supported their conclusions. It would be extremely expensive and time consuming to survey and map the surroundings of all 675 droids in order to identify which ones are in “low spots.” But the important issue they highlighted concerns how people perceive the meaning of the readings: even if the devices themselves are accurate, if someone looks at the display on the droid itself or on the MEXT map without understanding that several meters away might be very different, there’s a good chance they will get a false impression of radiation levels in the area. And because we can point to many examples of the droids being placed in “low spots,” and the government has not really provided enough information to demonstrate otherwise, citizens would probably be justified in assuming that the droids in general read lower than their surroundings.
Safecast has also checked the monitoring posts we’ve encountered, and tried to figure out how they are intended to work.
Four manufacturers produce similar units: NEC (see image at top), Aloka, Fuji Electric (which makes 2 kinds), and Rhinotech. All are solar powered, and net-enabled. The actual detectors inside seem to be well-made scintillators . We’ve seen a few dozen units in all, and while there’s often a noticeable discrepancy between what the droids read and what our geiger counters show, our RadEye scintillator usually agrees very closely. Nevertheless, we seem to notice greater discrepancies as readings fall below 0.1 microsievert/hr. We also couldn’t help but notice that of the dozen or so Rhinotech droids we saw, only one was actually working.
This could be just planned downtime, but they actually seemed to have manufacturing defects as well as maintenance problems, such as water inside the display (see photo below).
[Update: One of our volunteers in Koriyama pointed us to more information about the Rhinotech droids. They are actually manufactured by a company called Alpha Tsushin, which was awarded an initial contract worth 370 million yen, for 600 units. After they had been installed, MEXT cancelled Alpha Tsushin's contract and announced that it would source those units, plus 2100 more, from NEC and Fuji Electric instead. On its web site, MEXT stated their reasons as "the company was unable to meet the technical specifications and deliver on time." Quite a few bloggers have commented on this, pointing out that MEXT has not yet publicly stated what specs Alpha Tsushin was unable to meet, or how the units had been tested. It seems like a totally unilateral decision on the part of MEXT. Alpha Tsushin is suing MEXT for 370 million yen. The story has basically disappeared from the press, but the Rhinotech droids remain in place as a testament to waste and mismanagement.]
What about the effect of decontamination? There are hundreds of these units installed now, often in parks, at schools, and on playgrounds which were intentionally decontaminated beforehand to make them safer for children to use. Also, often the ground has been resurfaced in ways which suggest standard contractors’ practice more than attempts to affect readings. But we have seen many cases where the ground around the droid sports a new, labor-intensive surface that seems difficult to justify for reasons of simplicity or tidiness. For example, in Fukushima City recently we found one of the droids stashed a moderate distance away from immediate public view near Fukushima Station. It was located in a small grass park, the only green near the station, which means that dose rates will be lower there than what people experience in front of the station due to the different absorption characteristics of soil versus concrete. The asphalt on the path in front of the droid has been replaced with new, uncontaminated material. We measured the surface contamination in the park on “old” asphalt at 40-50,000 Bq/m2, while that of the new asphalt in front of the monitoring post was basically zero (after adjusting for the background radiation dose rate). The dose rates displayed on the monitoring post were very close to our Geiger counter (bGeigie nano) at 0.28 μSv/h, while the dose rate we measured around Fukushima station ranged between 0.3 and 0.5 μSv/h.
We found a similar situation at Fukushima University, where the dose rate in the parking lot was in the 0.4uSv range, while a monitoring post in the middle of a grass field showed around 0.23 uSv/h.
In response to the criticism from citizens’ groups, the government agreed last month to modify the location of batteries in the units which might be shielding the detectors, at a cost of ¥100,500,000. This is expected to eliminate a 10% inaccuracy in readings. But the problem is obviously bigger and more intractable than this. It goes back to the desire to make something “as easy as possible” for people to understand and use, versus not caring if it’s “as hard as possible.” We get the sense that nobody involved in the decision making process of establishing the specifications and usability parameters for the droids and the online system really cared enough to think about what information citizens would want and need, and why, and to design a good solution. No-one responsible for putting this information out was specifically tasked with thinking about what the best and most informative system would be, and to oversee it to completion. Instead, it seems a group of bureaucrats slapped together some minimum specs, probably with a lot of input from the eventual manufacturers, sent it out for bids, and took whatever came in. Then they subcontracted out the actual installation work to people who didn’t really care either. They contracted out a web site that looks good superficially but is actually nearly unusable and deceptively uninformative. We can only presume that many people lined their pockets along the way.
We’ve heard various justifications for the placement of the droids and decontamination around them, including that the goal was to show how low radiation would be when decontamination was complete, or was to provide low background readings so any sudden increase in radiation would be immediately apparent. And looking at how poorly executed the installation of so many of the units we’ve seen is, it’s hard to conclude firmly that providing deceptive readings was part of the plan, or that it would have been successful if it had been. But in fact, it’s hard to argue that they aren’t deceptive, or that those in charge aren’t aware of the fact. These units are helpful as far as they go, but it should be made explicitly clear that they represent point readings that cannot be accurately averaged to get area radiation levels. Although anyone with technical knowledge will probably realize it, they need signs on them stating clearly that the readings are valid only within a short radius, and people should know how much of the area has been decontaminated, and when. The web site should state this same information unambiguously as well.
This is especially true because towns like Kashiwa in Chiba have been doing regular surveys of all parks and playgrounds, as well as schools and other public areas, and posting the data online in a way that makes the changes over time clear. In the case of parks and playgrounds in Kashiwa, readings are taken at many locations and a map is posted at the entrances of the parks themselves and made available online. It is a very simple, effective, and unambiguous way to inform the public. And it’s clear that someone has taken responsibility for doing the legwork and maintaining the records:
What was and is needed is a public radiation dose monitoring system which gives representative readings for wide areas, not just spot readings for specially selected locations, but which also reflects the actual granularity of the contamination. If we were to specify it ourselves, we might insist on:
–Care taken to ensure consistent ground cover with the surroundings.
–Clear information on the droid itself describing both its capabilities and its limitations
–A map physically attached to the droid showing readings taken periodically in the surroundings up to 100m or more.
–Clear contact information on the droid itself where people can call, email, or look up on the web for more information.
–More easily useable web design, particularly to show both hot spots and averaging over a wide area, and to make the entire dataset openly available so it can be compared with others (like Safecast’s).
Eventually, I think, people nearby are going to need to “own” these droids, that is, take long-term responsibility for them, keep an eye on them, learn their quirks, learn how their readings compare to the surroundings, and establish good communication with the people who run the wider system. For that to work, of course, the people running things will need to show a kind of responsiveness we haven’t seen so far.
We saw one droid we liked which was different from the rest, at a school lunch preparation facility in Tamura.
It gives two readings, one for the parking lot outside the building, and one for inside. It has contact and technical information on it as well. It isn’t exactly the droid we’re looking for, but it shows that somebody is taking responsibility for it, and thought about what people would want to know. So these sorts of things are in fact possible. All it takes is for the people doing it to care enough about seeing it done right.