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How To Monitor Leaky Radioactive Water Tanks

timothy posted 1 year,25 days | from the for-fun-and-profit dept.

Japan 111

freaklabs writes "The radioactive water leaks are getting worse at Fukushima Dai-Ichi. In a recent New York Times article, it was mentioned that TEPCO didn't have a reliable way to monitor the water storage tanks for leaks. I decided to write a tutorial on how to wirelessly monitor water levels in storage tanks."

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first (-1)

Anonymous Coward | 1 year,25 days | (#44664673)


Haha (1)

barlevg (2111272) | 1 year,25 days | (#44664703)

Slashdotted yourself, looks like

Hardening (4, Interesting)

pjt33 (739471) | 1 year,25 days | (#44664739)

So now we'll never know whether they remembered to take into account radiation hardening.

Re:Hardening (3, Informative)

Anonymous Coward | 1 year,25 days | (#44664823)

I got to the site. Nope, no consideration at all that there's enough ionizing radiation to saturate all the transistors. And here I was foolishly thinking that a nice analog electromechanical system was described...

Re:Hardening (0)

Anonymous Coward | 1 year,24 days | (#44666403)

Who wants to go into a tank and install the sensors? Japanese broadcaster NHK reported that at 1 meter above one of the typical tanks the radiation exposure in one hour reaches the total that a worker may be exposed to OVER FIVE YEARS. They've burned through quite a few workers already. All operations must be very well planned to minimize human exposure.

Perhaps during full sunlight there's a enough of difference in outside tank temperature above and below the water line that it might safely sensed from remote IR cameras? Or how about a robot that goes by radiating audio white noise and senses reflections of that to measure the fluid-level-dependent accoustic resonant frequency of each tank? Or point a IR laser at various locations and remotely sense differences in the resultant heat being drawn away? (don't hit rubber/plastic gaskets or hoses with too much power) Some of the tanks are assembled with gaskets (that's what's failing, they're not all welded tanks). Perhaps visible deformation could be remotely measured to gauge fluid height/pressure?

They've got quite a mess.
At least the massive amount of water used is sufficient to avoid significant airborne steam. Hopefully major storms or earthquakes won't disrupt that. Steam was previously a serious contamination pathway.

Re:Hardening (1)

DemoLiter3 (704469) | 1 year,24 days | (#44666451)

The problem with the current leaks is that it's mostly beta radiation (from Tritium) and is quickly stopped in air, so in order to detect it, you need to measure close to the source. You're confusing it with the gamma radiation.

Re:Haha (1, Redundant)

jonathanjespersen (1162397) | 1 year,25 days | (#44664759)

Maybe he should have written an article on how to host an article to survive rapid bursts in page views.

Re:Haha (1)

nospam007 (722110) | 1 year,25 days | (#44665619)

"Maybe he should have written an article on how to host an article to survive rapid bursts in page views."

Or a wireless prickness-detector for managers, they stay safely out of the radiation zone, so the transistors will be safe.

slashdotted (5, Informative)

Anonymous Coward | 1 year,25 days | (#44664707)

I guarantee that there is frustrated engineer with a workable solution who spends half of all
his days trying to argue for the installation of monitoring equipment, but the organization

      - doesn't really want to monitor the tanks
      - is too incompetent to execute anything
      - has a turf war over who is supposed to be monitoring the tanks
      - is hung up on acquisition/budget issues
      - is hung up on safety protocols

Re:slashdotted (2)

emt377 (610337) | 1 year,25 days | (#44666025)

- Doesn't meet the 'reliable' standard as adopted by the nuclear industry

Re:slashdotted (1)

drolli (522659) | 1 year,25 days | (#44666189)

Yea. Doesnt even fit the standards for a normal industrial solution.

BTW: The arrogant idiot
-misunderstood the problem. If i want to monitor fpr leaks by measuring the height, i also have to measure the added fluid (which may be the bigger problem).

-is unaware that its easy to buy ready made, tested devices for his purpose. Look for any automation hardware manufacturers and for harsh environments. you will find the necessary building blocks, including certifications easily (yea. ~1000 times more expensive than the erduino board, but they will work.

monitoring level != monitoring leaks (1)

pepty (1976012) | 1 year,24 days | (#44667277)

Is more water still being added? How much? Do they know? If the level is supposed to stay constant, don't mess with opening a radioactive tank to install a sonar unit, just mount a fluid level sensor on the exterior of the tank. []

Re:slashdotted (1)

stooo (2202012) | 1 year,24 days | (#44668583)

Yes. Monitoring leaks is not in the interest of tepcos at all.
Leaks improve their "storage" capacity situation.... Sadly. And we eat the fish.

radioactive water (5, Interesting)

roman_mir (125474) | 1 year,25 days | (#44664741)

So this is fine when it concerns non-radioactive water, but this solution wasn't tested in an environment where the radioactive levels are higher than usual, there was no test case in the story for that. Will the electronics live long enough? Also what about humidity, how long before this stops working because of higher humidity levels?

Re:radioactive water (4, Interesting)

Half-pint HAL (718102) | 1 year,25 days | (#44664789)

Heck, I'm wondering whether you can do anything wirelessly in a radioactive environment -- ionising radiation most bugger up the charge in an antenna something chronic....

Re:radioactive water (1)

roman_mir (125474) | 1 year,25 days | (#44664955)

How about shielding the antenna with some metal or maybe using a cantena? What about grounding the antenna as well?

Re:radioactive water (1)

solidraven (1633185) | 1 year,25 days | (#44666171)

The real problem is getting the digital part of it to a reliable point. You'd have to use military grade radiation hardened hardware, and even then you're looking at a lifespan of days when it has to survive in such a tank unless you pad it with heavy metals, which has several practical issues as encasing RF stages in a thick slab of metal generally doesn't improve stability or reliability. The antenna is the least of your worries I think.

Re:radioactive water (1)

fuzzyfuzzyfungus (1223518) | 1 year,25 days | (#44665703)

Honestly, I'd be inclined to do it the 'keep it really, really, simple, TEPCO' way:

Float style liquid level meters are extremely simple devices. Small lighter-than-water float on the bottom, a rod(ideally with stripes or distance markings, like scale bars), and a sleeve in the lid of the tank that keeps the apparatus upright and allows the rod to move up and down freely.

If you do have rad-hard electronics in place, an optical sensor for the stripes, or a hall effect sensor for a rod with magnets at intervals, or similar, are easy to add. If not, the amount of protruding rod can be read from some hundreds of meters or more with a wholly unexciting pair of binoculars.

Re:radioactive water (1)

Firethorn (177587) | 1 year,25 days | (#44666045)

If you do have rad-hard electronics in place, an optical sensor for the stripes, or a hall effect sensor for a rod with magnets at intervals, or similar, are easy to add. If not, the amount of protruding rod can be read from some hundreds of meters or more with a wholly unexciting pair of binoculars.

A bit more high-tech, but which allows you to keep a goodly distance away would be a simple infrared sensor system POINTED at the tanks.

Reasoning: Liquids tend to keep their temperature more stable than solids. Tanks tend to not be well insulated(if they are, get a more sensitive sensor). Temperatures vary through the day, but the liquid shouldn't change much. Ergo if you point a infrared sensor at a tank, you should be able to easily draw the water line. A little calibration for temperature of the liquid if you need to account for expansion/contraction due to it(how handy that you already know it's temperature!) and you have a very accurate measure of how much water is in the tank.

Heck, MIT has a page with fancy images [] about doing just that and more...

Re:radioactive water (1)

solidraven (1633185) | 1 year,25 days | (#44666187)

IR sensors are already very noise sensitive as it is... Introducing radiation won't do much good, even at a distance. It'd be worth a try but I don't see it working long either.

Re:radioactive water (1)

Firethorn (177587) | 1 year,24 days | (#44667231)

There's a reason I linked the MT site - it has lots of images of them using infrared technology to determine tank levels and more.

Depending on the size of the tank, radiation isn't going to do much at all. Worst case you might have to replace the sensors more often, but remember that you're not 'testing' a narrow strip, you're taking an image of the whole tank.

Re:radioactive water (1)

Half-pint HAL (718102) | 1 year,24 days | (#44668439)

IR sensors are already very noise sensitive as it is... Introducing radiation won't do much good, even at a distance. It'd be worth a try but I don't see it working long either.

Perhaps, but an important difference between the IR radiation and the atomic radiation is that the IR comes from the outer surface of the tank and the atomic radiation from the contents. That means you can set up the camera to point at a corner of the tank at an angle such that there is very little water in the camera's line of "sight" (even though the water is out of sight in terms of visible and IR light, it can still be "seen" in the gamma spectrum or as particle decay).

You could also use a prism to protect the detector -- alpha and beta radiation won't refract, and gamma will refract differently from IR, so the sensor could be well isolated at the end of a thick lead tube. The prism made need fairly frequent replacement due to alpha and beta damage, but that shouldn't be a huge issue.

Re:radioactive water (1)

solidraven (1633185) | 1 year,24 days | (#44668551)

That's not a bad idea actually, if you add sufficient lead padding that might just work quite well. The question is off-course how much of a temperature difference you'd be looking at. And you'd have to choose the prism and lens materials very well, else you could end up with x-rays slamming into your sensor at an above average frequency which would significantly increase the noise levels. So you'd have to average the data over a considerable time to be certain.

Re:radioactive water (1)

drinkypoo (153816) | 1 year,24 days | (#44669597)

A bit more high-tech, but which allows you to keep a goodly distance away would be a simple infrared sensor system POINTED at the tanks.

How about a solution halfway between; the tank has a prism on top and the tank level is measured via inspection by a remote laser system. The monitoring system is far away from the tanks so if radiation ever were to be an issue, it still wouldn't be.

Re:radioactive water (1)

dbIII (701233) | 1 year,24 days | (#44667103)

Why not? Something like that has worked with oil storage tanks for around a century and I'm sure other tanks a lot longer than that.
We've seen a repeat of one of the mistakes of TMI - not having enough instrumentation to work out what the fuck is going on when things go bang and relying on sheer luck that it isn't going to get any worse. For some reason nuclear thinks it's special and doesn't need to take the care that other hazardous industries take (original TMI instrumentation mistake), then fails to learn from the history of it's own industry (the backslide that led to the recent fuckup). Do we really need a massive nuclear fuckup every two decades to remind them? We need adults in charge that respect the dangers instead of fanboys chanting "clean" as if it's washing detergent.

Re:radioactive water (1)

fuzzyfuzzyfungus (1223518) | 1 year,24 days | (#44667501)

The only potential issue that springs immediately to mind would be vapor escaping through the sleeve in the lid (though, at this point, is anybody even going to notice a little extra evaporation in the face of all the deliberate and ongoing-accidental water releases?), and the possibility of the measuring rod 'binding' if it somehow ends up tilted too far from vertical and placing excessive force on just a couple of contact points (which would quite possibly cause the slip sleeve to bite into the rod and keep it fixed in position even as the water level changes). I'm sure that some clever mechanical engineer has a design for a superior leak-resistant and low-friction slip sleeve; but I don't know the details of such a beast.

Aside from that, though, it was a perfectly serious suggestion. Materials cost, per tank, is peanuts, float-type sensors are fully compatible with electronic instrumentation, if desired; but also work totally passively, and the failure mode still allows you to track state from a safe distance with a clipboard minion and some binoculars (unlike the failure modes of ultrasonic rangefinders, photointerrupters, or similar widgets, which might stop responding or start sending back dodgy numbers, with no ability to verify except by sending somebody into the tank farm to check it out.

I wouldn't want to be the lucky guy who gets to stand on the roof of the shoddily-built radiation-goo tank and retrofit a sensor sleeve; but including it in the design of new tanks wouldn't be difficult.

Re:radioactive water (1)

thegarbz (1787294) | 1 year,25 days | (#44666213)

The antenna does not need to be in the tank or exposed to radiation. Not to mention that noise sensitivity is a problem on the receiving side, not the transmitting side.

Re:radioactive water (1)

slick7 (1703596) | 1 year,24 days | (#44666555)

You would be better off using crooked, corrupt, too long in office, politicians. Maybe once in their lives they could do something positive for society. There's plenty to go around and I'm sure they won't be missed, except by their greedy lobbyists. And hey, there are all those greedy lobbyists too, for backup and replenishment.

Re:radioactive water (0)

Anonymous Coward | 1 year,24 days | (#44667465)

Heck, I'm wondering whether you can do anything wirelessly in a radioactive environment -- ionising radiation most bugger up the charge in an antenna something chronic....

It might be possible to turn that to your advantage... If ionizing radiation does bugger up the charge in an antenna, it follows that an antenna is (at least to some limited degree, your mileage may vary when it comes to sensitivity and linearity) also a radiation sensor. And a relatively cheap one, at that. You'd need a method for 'reading out' the charge of an antenna; but unless we are talking some seriously exotic antenna flavor here, you could afford to string the things like christmas lights all over the area.


mha (1305) | 1 year,25 days | (#44664795) []

Maybe the submitter wrote about it, but the site is unavailable right now and his summary certainly does not reveal he knows a thing about the special considerations of electronics in radioactive environments. There is a reason we (in the East German army) had big tube-powered big bulky radios instead of smaller transistor-based ones.


Anonymous Coward | 1 year,25 days | (#44664849)

A tank with radioactive water is not a problem for transistorized equipment. Tube-based equipment is what you need in a nuclear war, they survive the EMP when a nuke goes off somewhere slightly farther away than lethal. Low-level radiation from a storage tank is much easier to deal with - there is no EMP to worry about.

You should have... (1)

mha (1305) | 1 year,25 days | (#44665087)

...followed the link I provided. So again, for you: []

No problem, sometimes I don't read before responding myself.

Re:You should have... (0)

Anonymous Coward | 1 year,24 days | (#44668335)

I did not say that transistors need "no hardening". Of course they do - but there is no need to go with tubes just to monitor some radioactive water.

Ionizing radiation mess with charged particles, as that webpage points out. The simple solution is to use bigger transistors in the sensor. A gamma ray that will flip several bits in an integrated circuit, won't do much to a power transistor the size of your fingernail. Don't do stupid things like sticking a computer inside that tank. Build a simple sensor that only need a few transistors - large ones. Send the signal out on a wire, digitize & compute somewhere else where there is less radiation.

Computerized sensors that communicate over ethernet is nice (and relatively new), but it is a sort of equipment that doesn't fit everywhere. So don't use it everywhere then. Analog signals can be sent over wires too, to be processed elsewhere. Noise can be kept out in many ways - using more power is a simple one. Putting the electronics in a metal box tend to dampen radiation too.

Tubes might work well, but will be much larger and require much more power than transistors. And they burn out regularly - similiar to lightbulbs. Then you need a eunuch to replace burnt out tubes in your radioactive facility. Such people don't come cheap . . .

Re:WHO VOTED THIS DOWN (2, Interesting)

roman_mir (125474) | 1 year,25 days | (#44664937)

I managed to read TFA and the submitter only mentioned the words "radioactive" once or twice and never considered the challenging environment that his device would have to be used in.

Personally I don't believe he considered that side of the problem. Would the design work at all? I think it would for some time, but it probably would fail after a short time period without hardening against radiation and humidity.


Anonymous Coward | 1 year,25 days | (#44664997)

I managed to read TFA and the submitter only mentioned the words "radioactive" once or twice and never considered the challenging environment that his device would have to be used in.

Personally I don't believe he considered that side of the problem. Would the design work at all? I think it would for some time, but it probably would fail after a short time period without hardening against radiation and humidity.

Which, of course, probably means he's prime material to be hired by Tepco!!
They obviously only hire incompetent people who don't understand "DANGER, DANGER WILL ROBINSON!!" and flailing robot arms probably means something dangerous is happening, and instead ignore it completely - failing to account for the fact that his hardware has to work in a radioactive environment would make him a perfect Tepco upper management candidate.

TIL: Some registered /. users may start at -1 (1)

mha (1305) | 1 year,25 days | (#44665097)

Okay, so no one voted roman_mir down, his articles start with -1, Slashdot punishment for low score. Never knew that was possible. Good comment this time though, a step to i the /. score ;-)

Re:TIL: Some registered /. users may start at -1 (1)

Captain Segfault (686912) | 1 year,25 days | (#44665153)

You must be new here.

Re:TIL: Some registered /. users may start at -1 (-1)

Anonymous Coward | 1 year,25 days | (#44665411)

looking like a low-iq loud nigger is life's punishment for not reading the faq []

how many shekels did you spend on that low-4-digit uid?


AmiMoJo (196126) | 1 year,25 days | (#44665713)

Sure, it's possible, but it would take some considerable time to develop such a system. You can't just buy an off-the-shelf radiation hardened Arduino. Someone is probably working on it, but the statement made by TEPCO that they have no way in the foreseeable future to monitor levels is probably true.

As ever, no-one planned for this eventuality.

Solar Perhaps (1, Interesting)

ShooterNeo (555040) | 1 year,25 days | (#44664745)

The only thing it's missing is a small solar panel to keep the battery charged. That way, no one has to climb those tanks of deadly radioactive water unless hardware has actually failed. Some of those Arduino boards already have battery chargers on them, but if not, a small regulated LiPo or NiCad battery charger is what you need. Then you just need a solar panel that is small and has the right output voltage. seems to sell a 10 watt, 12 volt panel for $15. No big deal, and that's more than enough juice. Size the panel right, and you can do the monitoring continuously for a measurement every minute or so. (not that this really matters, but why not overdeliver?)

Re:Solar Perhaps (1)

Half-pint HAL (718102) | 1 year,25 days | (#44664803)

How does solar power help inside a hermtically sealed containment tank...?

Re:Solar Perhaps (1)

ShooterNeo (555040) | 1 year,25 days | (#44664859)

it's on top of it

Re:Solar Perhaps (1)

camperdave (969942) | 1 year,24 days | (#44667493)

How does solar power help inside a hermtically sealed containment tank...?

Solar cells can respond to radiation as well. All that's needed is for energy to dislodge electrons in the cell. It's the same basic principle that pacemaker batteries use.

Re:Solar Perhaps (5, Informative)

icebike (68054) | 1 year,25 days | (#44664831)

The radiation in these tanks is easily stopped by the tank wall. (Its almost solely Beta radiation). So climbing the tank is not particularly a problem.

Water is always being pumped into and out of these tanks (they are used to circulate cooling water for shut down reactors and the separation plant where radioactive elements are separated). As such, water level in the tank is not static, there are surges as pumps start and stop, etc. Think of the tank as a buffer in a continuous flowing circuit. There are systems to make sure there is always sufficient water in the circuit, and water may be added at locations far removed from the actual tank. Its vitally important to make sure there is adequate cooling water, it can never be allowed to run dry.

When you view it this way, missing a couple hundred gallons over the course of a month is not something you can count on detecting by monitoring water lever in a tank, because it fluctuates naturally, loss will be automatically compensated by new water additions.

So thanks for playing along, but I believe this issue is best left to the big boys,(even the ones you might, in your make-believe environment, consider to be incompetent). The problem is much more complex than you know, and won't be solved with your cute little lash-up toys.

Re:Solar Perhaps (0)

Anonymous Coward | 1 year,25 days | (#44665081)

If your input quantities and output quantities are well-defined, as I suspect they would be, then you could continously integrate the volume of water in the tank with the expected volumes entering and exiting the tank at any point in time. If there is a discrepancy between the volumes computed using those values then you know you have a leak.

Since I've become an engineer I've noticed that there are a lot of problems that people can solve but that they choose to leave up to the "big boys" because they assume they don't know anything. These problems often have simple, common-sense solutions.

In the case of sensing volume in a tank whose contents are constantly being removed it's really not that difficult. A 1st-year calculus student could do the math on it, so I'm not sure why you're suggesting we would want to throw up our hands and accept that it's an unsolvable problem. The only thing that's missing is real-world data, and it's not impossible to collect or estimate any of that data.

Re:Solar Perhaps (2)

joe_frisch (1366229) | 1 year,25 days | (#44665155)

When you have a constant inflow and outflow, if there is any calibration error on the flow meters that error will integrate over time to look like a gain or loss in level. You could imagine having flow and level sensors everywhere, but you still have issues with temperature variations (the thermal expansion of water isn't all that small). Still you could do it with arrays of temperature sensors in each tank, level sensors and calibrated flow-meters. Starts to get pretty complex.

There are lots of commercial solutions out there for level monitoring with distributed data systems but when you are trying to find leaks that represent a small fraction of the total volume it gets difficult.

It is still possible that a simple level monitoring system would help - but if so, they might as well use a commercial system .

Re:Solar Perhaps (2)

freaklabs (1359341) | 1 year,25 days | (#44665183)

Hi. Actually these are storage tanks and are designed to hold water. Once they are filled, its unlikely water is pumped out unless there's a suitable place to dump it. That doesn't seem to be the case.

Re:Solar Perhaps (1)

khallow (566160) | 1 year,25 days | (#44665489)

Once they are filled, its unlikely water is pumped out unless there's a suitable place to dump it.

There is - in the reactors or by evaporation. I gather this is part of their cooling system. In which case, they want to both circulate the water through the reactor and cool it off at some point.

Re:Solar Perhaps (1)

icebike (68054) | 1 year,24 days | (#44666557)

Hi. Actually these are storage tanks and are designed to hold water. Once they are filled, its unlikely water is pumped out unless there's a suitable place to dump it. That doesn't seem to be the case.

No, the tanks levels are constantly changing, these tanks are in the cooling water refining circuit.

See: The Register article []

Well, no. The situation is this. The melted-down cores at the damaged reactors (the site is not "crippled", two reactors were undamaged and will return to service) are still hot - though much less hot than they were two years ago - and need to be cooled. This is done by pumping water through their buildings, then sucking it out again and putting it into holding tanks before purifying it to remove the radiation it picks up from the cores. Then it gets used again.

Re:Solar Perhaps (0)

Anonymous Coward | 1 year,25 days | (#44665841)

Informative but Ooooo you bitch.

If its beta, then put the panels inside the tank (0)

Anonymous Coward | 1 year,25 days | (#44664883)

Can you get enough juice from the radiation to power the device?

Re:Solar Perhaps (2)

thegarbz (1787294) | 1 year,25 days | (#44666225)

No what this needs is a proper industrial solution fit for purpose, not some home made solar gear with an arduino strapped to it. We use wireless guided wave radars from Emerson at work and they last in excess of 10 years on a single battery charge.

Core meltdown at Freaklabs (-1)

Anonymous Coward | 1 year,25 days | (#44664749)

Send the containment unit!

slashvertisement (4, Interesting)

Tom (822) | 1 year,25 days | (#44664757)

Because your website needs more hits and the experts in Japan certainly never thought of some of the most obvious ideas, yes?

You may not be familiar with japanese culture. I am, at least a bit.

In the US, this admition would translate to "we can't be arsed to give it some attention".
In Japan, this is a major loss of face and could well mean the end of someone's career.

This face thing is a major problem in many cases in Japan, because people won't admit to mistakes until they can't hide them anymore. Yes, even more so than in the West.

It would be fantastic if someone from the japanese geeks involved in the whole thing would read /. and rip your blog-wiseassing to shreds. Unfortunately, that's unlikely and so your ego can feed on a false sense of superiority.

Re:slashvertisement (0)

Anonymous Coward | 1 year,25 days | (#44665105)

Chris Wang ("Akiba") has lived in Japan for about ten years now. He's familiar with Japanese culture. He's also fairly well-respected in the maker subculture.

He's not blog-wiseassing, he's demonstrating a solution that, however obvious it may seem to you in retrospect, required modifications that he documented well and that might benefit other people working with wireless technologies or battery-powered sonar equipment. The project suggested itself after a charity workshop on similar problems in monitoring water supplies for Tibetans (including monks). People like Chris Wang provide low-cost, effective uses of technology to solve real-world problems, and they provide their expertise and knowledge for no cost, generally documenting their work so that other people can build on their experiences. We could have a world where all solutions are expensive, proprietary, and involve trade secrets that hinder progress, but, because of makers like Chris, we have a better world than that.

Re:slashvertisement (3, Informative)

thegarbz (1787294) | 1 year,25 days | (#44666245)

No what he's doing is putting home made crap in an industrial environment it's not suited for.

If they wanted wireless tank level measurement they would:

1. Pick up the phone.
2. Call Yokogawa
3. Have wireless installed within a few weeks and for the cost of around $2k per tank which is a rounding error compared to the cost of the cleanup effort.

There's no technical problem that's preventing this.

Re:slashvertisement (1)

Tom (822) | 1 year,24 days | (#44668471)


Credentials aside (I admit he has better than I gave him), if you post your "solution" on your blog instead of telling the people who can use it, you are stroking your ego, not trying to help.

Re:slashvertisement (0)

Anonymous Coward | 1 year,25 days | (#44665137)

The author has done work in this area and was offering help. The solution was interesting and not obvious (not an advertisement for a prepackaged product). I loved it strictly from a hobbyist perspective. All source was provided.

If you have concerns about the solution please state those clearly for everyone. Your concerns for "loss of face" are irrelevant.

Re:slashvertisement (1)

thegarbz (1787294) | 1 year,25 days | (#44666259)

The solution was interesting and not obvious

For everyone OTHER than a run of the mill instrument engineer.

Re:slashvertisement (3, Interesting)

freaklabs (1359341) | 1 year,25 days | (#44665195)

Hi. I live in Tokyo, am one of the founders of Tokyo Hackerspace, and would probably be considered one of the Japanese geeks.

Re:slashvertisement (0)

Anonymous Coward | 1 year,24 days | (#44668109)

Quoth Tom:

You may not be familiar with japanese culture. I am, at least a bit.


It would be fantastic if someone from the japanese geeks involved in the whole thing would read /. and rip your blog-wiseassing to shreds. Unfortunately, that's unlikely and so your ego can feed on a false sense of superiority.

You live in Germany. He lives in Japan. In fact, he's worked on projects concerning the Fukushima exclusion zone, including designing radiation-monitoring equipment with But, you knew that before you accused him of "blog-wiseassing" and "a false sense of superiority, right?"

I remember when Slashdot wasn't nearly this petty or mean-spirited. The guy's not even trying to sell you anything.

with a long stick (1)

Anonymous Coward | 1 year,25 days | (#44664821)

make that a very long stick

Radiation failure (1)

Snuggles (74048) | 1 year,25 days | (#44664827)

The electronics and piezo element in the ultrasonic sensor will fail fast in rad environement.

And then somebody must go there, install and later replace the sensors..

You win! (-1)

Anonymous Coward | 1 year,25 days | (#44664869)

This is by far the stupidest thing i've seen on slashdot in recent memory.

I sure hope you're just being a sarcastic douchebag with such obvious tech.

Since people way smarter than you will ever be deal with nuclear power.

You suck. Your blog sucks. Die.

I hope you do perl programming (1)

nedlohs (1335013) | 1 year,25 days | (#44664897)

Since you certainly have the Hubris part mastered.

Next tutorial: "unslashdottable webserver" (0)

Anonymous Coward | 1 year,25 days | (#44664903)

No usable material inside this comment.

Not hard (2)

girlintraining (1395911) | 1 year,25 days | (#44664919)

I don't get it; If your water heater was leaky, you'd notice it right away. Same if your gas tank, radiator, or brake fluid reservoir on your car was. In fact, the main way people figure out something is leaking is because something is present where it shouldn't be, and a supposedly-contained source is nearby.

You don't need complex wizz-bang devices to figure this out. You need the Mark I Human Eyeball. TEPCO knew, okay? They didn't want to know, so they ignored evidence that it was leaking. "Well, the tanks emptied out... but it must have just been normal evaporation", or "we expected a certain amount of leakage", or "we were understaffed," or "it was the contractor's fault," or any other rationalization you can think of. The problem here is not technology and it won't be solved by technology.

The problem is management didn't want to know it had a problem, because plausible deniability means no responsibility. So they will go to incredible lengths to avoid noticing the problem. You can't slashvertise your way into a solution here... "wifi sensors! That'll fix it!" Okay... who's going to monitor the sensors? What are the sensors actually sensing? Mind you... sensors being improperly read is what led to the Three Mile Island disaster. Do you trust your $12 wizz-bang to do the job of a trained nuclear engineer? This is what it all comes down to: The tanks were leaking, and somebody noticed. I don't know who that somebody is, but somebody knew enough to look. Whether they did or not...

TEPCO management needs to be dragged to Geneva and held for crimes against humanity. No, I'm dead-serious about this... Japan has a long an inglorious history of allowing epic amounts of corporate failure because it's not in their culture to admit wrongdoing. Trains fly off tracks and crash into apartment complexes and outside investigators conclude that a punitive and stress-inducing corporate culture was what primed the young train conductor to race around the bend too fast to stay on the tight schedule... and the corporation, faced with dozens of fatalities... says everything is fine and keeps the policy as-is: It was the conductor's fault. He couldn't handle our "high standards". This is a prime example of Japanese culture people. It's toxic and it needs international attention and condemnation.

It does not need a wiz-bang sensor monitor. It needs a gun to the head and a "come with us, we're taking a long flight to your trial, asshole".

Re:Not hard (2)

Njovich (553857) | 1 year,25 days | (#44664995)

Good luck discovering if your radiator lost a couple of ml of water.

These amounts may sound like a lot, but for individual leaks, they may be tiny compared to the amount of water they have.

Re:Not hard (1)

girlintraining (1395911) | 1 year,25 days | (#44665113)

These amounts may sound like a lot, but for individual leaks, they may be tiny compared to the amount of water they have.

True, but it doesn't matter what the amount is if nobody's bothering to look.

Re:Not hard (1)

khallow (566160) | 1 year,25 days | (#44665497)

True, but it doesn't matter what the amount is if nobody's bothering to look.

What makes you think no one is bothering to look?

Re:Not hard (1)

girlintraining (1395911) | 1 year,25 days | (#44666299)

What makes you think no one is bothering to look?

Decades of experience dealing with middle managers.

Re:Not hard (1)

khallow (566160) | 1 year,24 days | (#44667825)

So you don't have a reason for thinking that. How come I'm not surprised?

Re:Not hard (1)

achbed (97139) | 1 year,25 days | (#44665295)

Rule #1 for radioactive substances: don't lose any. If you're going to build a system to contain radioactive material, it should include monitoring so that you know if any goes missing. Losing 200 tonnes of radioactive material is not a "cost of business" or "within acceptable error rates". The error rate on this stuff should be 0 for a reason.

Re:Not hard (1)

mikael (484) | 1 year,25 days | (#44665321)

There's always the Waterworld solution - take those TEPCO executives, tie them to a rope and lower them into those storage tanks along with some water-level lines on the side of the tank, and have them provide hourly readings: []

Re:Not hard (1)

celle (906675) | 1 year,25 days | (#44665975)

"They didn't want to know, so they ignored evidence that it was leaking."

      If you had tfa'd, you would have noticed that Akiba had the monitor readings submitted to the internet. That way the public knows immediately if something is going on and TEPCO is fucking them around. That's why TEPCO would 'never!!' implement such a system because they could be held accountable for their behavior which is something no business wants. Especially a company with real public responsibilities that's already at the bottom of the credibility ladder like TEPCO. As to his post, Akiba already has devices being used in the exclusion zone so he is qualified to write up what he has.

Re:Not hard (0)

Anonymous Coward | 1 year,24 days | (#44667317)

Exactly. The tanks should be in a dyked area with a containment pit for catastrophic failure assuming they are following any sort of plant design best practices. They must have known for a while the tanks are leaking and are sticking their heads in the sand.

Call me a cynic but.... (0)

Anonymous Coward | 1 year,25 days | (#44664929)

I suspect the tanks are being made to leak. One of the articles I read said something to the effect that an open valve was responsible for one of the leaks. They are running out of room for tanks and it isnt politically acceptable to drain directly into the sea. Leaky tanks are probably worse for Japan's water supply but easier to explain away.

Besides that the site is down... (0)

Anonymous Coward | 1 year,25 days | (#44664969)

... does this "plan" take into account that this is highly *radioactive* water, and the hardware needed probably should be Rad-Hard (radiation hardened) and not just your average off-the-shelf Zigbee or other radio interface? It's easy to monitor water levels with a little SBC with a Zigbee or something, it's an entirely different story when it's going to be subjected to radiation over the long term.

The problem isn't technology (3, Interesting)

JoeyRox (2711699) | 1 year,25 days | (#44664971)

The reality is TEPCO doesn't want the radiation monitored. For the same reasons the beef industry doesn't want cows tested for Mad Cow. The absence of testing allows for plausible deniability.

Re:The problem isn't technology (0)

Anonymous Coward | 1 year,24 days | (#44668405)

"Plausible deniability" is not an issue. When you run a nuclear plant, you are responsible for it. If anything unexpected happens, it is your fault. Both that it went wrong, and that it was unexpected.

A tsunami of that size was not "unexpected" at the time. It was expected once every 100 years or so. That is not often - so economically it may make sense to close down for massive repairs. Preparing so well that you restart immediately after the sea calms, might cost more than months of downtime when it occur so rarely. Enormous walls costs to maintain.

But having radioactive leaks and explosions - that was not acceptable. If you really need emergency cooling after a shutdown, you'd better have a cooling system that survives the largest tsunami you can expect ever. Either that, or you build your reactor buildings so they can contain an uncooled meltdown indefinitely. (The uncooled fuel only have energy to melt so much concrete (or whatever) after shutdown - it is possible to have much more.)

"We did not know/expect" is not an excuse for anything. Even having to say such a thing, is itself a loss of face.

A culture that likes to sweep things under the rug is best countered by enforced transparency. Someone else should monitor the nuclear industry. An independent organization that do frequent surprise inspections, and who have their own instruments wherever they like on-site. Someone who can only loose face by hiding stuff - and who wins respect by exposing stuff.

Contact TEPCO, Now! (2, Informative)

Anonymous Coward | 1 year,25 days | (#44664985)

Wow, what an amazing totally thought out plan!

I love how you thought about radiation causing random flipped bits, the need for adaquete power and shielding, etc.

Amazing, I didn't know the Arudino was rad-hardened and certified for use in safety critical industrial applications. I will instruct everyone I know to use the Arduino for everything. Why pay hundreds of thousands when I can get all the rad-safety and life-safety cerified components for pennies on the dollar!

Re:Contact TEPCO, Now! (1)

BitZtream (692029) | 1 year,25 days | (#44665229)

You put the sensor in the tank, the Arduino outside the tank. The radiation is mostly beta and won't make it through the tank wall anyway.

Also, 'radiation hardened' ATmega chips are readily available to anyone, so a radiation hardened Arduino is as well. Just swap out the one that comes with it to the ones they make for these places. Before you lose your shit, you might want to get a clue about what is actually available.

Certified? No of course not, but do you want no monitoring that will never work, or uncertified that might work?

Of course, an ultrasonic sensor is pretty stupid to use. A simply float mechanism and deboucer is FAR more intelligent.

Re:Contact TEPCO, Now! (2, Informative)

Anonymous Coward | 1 year,25 days | (#44665325)

Note that an Arduino is a lot more than an ATmega. There's a USB interface chip (usually a smaller AVR, but it's SMT, so harder to replace than the socketed ATmega), there's a voltage regulator, there's a clock source of some sort, etc. How sure are you these elements will do fine in your supposedly "radiation hardened Arduino"?

Re:Contact TEPCO, Now! (1)

BitZtream (692029) | 1 year,24 days | (#44667655)

Switch to the ATmega internal clock, and use the serial port directly rather than through the USB to Serial secondary ATmega.

No, the voltage regulator isn't going to give a shit about the radiation in this case. Pretty much everything else are passive elements without worries.

Lets be clear: There are systems to do this that are so cheap and certified that TEPCO could by them and NEVER notice the error on the books, but making an Arduino usable in this situation is trivial as well.

The idea of actually using a hacked together solution for this is stupid, but possible. Buying a 2k 'certified' unit that just measures the internal level via an external sensor on the side of the tank would be much more intelligent.3

Re:Contact TEPCO, Now! (0)

Anonymous Coward | 1 year,25 days | (#44665507)

How you get that puzzling idea that there is no strong radiation OUTSIDE the tank from all the leaking and the whole disaster after the Tsunami?
You are still thinking in some "artificial environment box".

Thx but no thx (2, Informative)

Anonymous Coward | 1 year,25 days | (#44665001)

Sorry mate...

I used to hack for a company that would do this for about $25 a month + installation fees and hardware costs. Although if someone had used the words "nuclear" we'd probably have consuled a lawyer and said hell no.

Complete with certified electricians, low power, cellular, satellite, and 802.x plans, off site data storage, backups, recovery, control, and a pretty little website that could get you the data a dozen different ways including read into your ear over the phone. For the big boys some of our stuff was even in escrow.

But you see, you didn't use radiation hardened electronics.

You're using an arduino which even in its deep sleep is consuming at least 4x as much power as we did while awake nearly a decade ago. And you've got no backup or emergency cry. Or thermistor, or cut off, or sensor stabilization routine...

Look, it's a noble effort for a home hacker, and the proof of concept if you didn't believe it was possible is cute.... and to somebody who can't go corporate I can see why you'd use this at home ...

But you really haven't addressed any of the core engineering issues, and have added an additional maintenance problem.

Now frankly, this case is so straightforward it's nothing a competent engineer and developer can't solve -- you've got the mostly right sensors, you just need to package it up properly. And that is the problem. You're going to pay a small fortune for the certifications you'll need to touch that industry.

Also, as others have said -- the problem isn't that they can't fix it. It's that TEPCO is culturally poisoned. But maybe the VP of engineering will save some face by falling on his sword.

Radiation hardened? Nope. (-1)

Anonymous Coward | 1 year,25 days | (#44665009)

Shove your arduino right back up your ass you pompous dipshit.

effects of radiation (1)

confused one (671304) | 1 year,25 days | (#44665075)

I wonder if he considered the effects due to the radiation in the tank, on the PZT elements used in the ultrasonic transducers.

Re:effects of radiation (1)

whois (27479) | 1 year,25 days | (#44665819)

Of course he didn't, so let's ignore his solution and start talking about things that might work.

My thoughts:
Entirely mechanical in the tank and electrical outside. You could use two columns of liquid to measure pressure, one on the inside and one on the outside, then read the height of the column on the outside. It would need some way of keeping the radioactive water out of the columns but still allowing it to put pressure on it.

Might not be feasible to build such a device now that the tank is full of radioactive water too. There is also the question of precision because depending on fluids used, size of the tank, size of columns, etc you might not be able to monitor closely enough to observe small amounts of loss.

Hit it with a stick (0)

Anonymous Coward | 1 year,25 days | (#44665377)

Hit it with a stick, the tank will sound different in parts that have water and parts that don't. That will give you the height of the water, use 4th grade math to calculate volume based on the known dimensions

Ice doesn't leak (2)

Teun (17872) | 1 year,25 days | (#44665565)

Providing these are storage tanks whose content is waiting until it can be cleaned up I would suggest to freeze them.

Drilling a hole?! (1)

zmooc (33175) | 1 year,25 days | (#44665987)

I really like the idea of drilling additional holes in nuclear storage facilities!

I guess it shouldn't be too difficult to detect water level changes from the outside of the container. The pulse response of the container will change with the water level. If I can do it by tapping on a bottle with a coin or something like that, a sensor could easily measure this as well.

The entire Pacific ocean is a radio active. (1)

Ralph Ostrander (2846785) | 1 year,24 days | (#44667153)

Wasteland now.

amykatieamykatie (-1, Offtopic)

Amykatie Amykatie (3029541) | 1 year,24 days | (#44667557)

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Answer (0)

Anonymous Coward | 1 year,24 days | (#44667615)

Put an Obama cam in the TEPCO CEO's toilet.

Hell, I could point to an area of expertise (1)

Trax3001BBS (2368736) | 1 year,24 days | (#44667819)

My area

The Hanford Tank Farms house 53 million gallons of high-level radioactive and chemical waste that is the byproduct of “reprocessing” spent nuclear fuel.* . []

massive underground storage tanks ranging in capacity from 55,000 gallons to more than 1,000,000 gallons to hold the wastes. Scientists believed that the tanks would only be used temporarily until a permanent place to dispose of the waste was identified. []

Yucca Mountain nuclear waste repository isn't panning, out storage waste levels leakage control are well known.

And next to a Ocean, my how times change (1)

Trax3001BBS (2368736) | 1 year,24 days | (#44667845)

"Tepco has built nearly 1,000 tanks at the sprawling complex to store as many as 335,000 tons of contaminated water, the product of coolant pumped into the reactors to keep their cores from overheating,"

Old Plutonium reactors in this area used to pump cooling water through the reactors then into huge holding tanks too cool heat wise before being released back into the Columbia river. There were two holding tanks and switched when one was full. Fuel elements at that time were maybe 1.5 inches wide, 6 inches long;
and they popped like popcorn I've heard it say -they were still learning how to do it.

An Eastern Washington newspaper sampled a lot of areas for radiation, where the Columbia river turns after the reactors there a build up and fairly high levels.
I have lived on and off about 50 miles downstream of the Hanford Site all my life as has hundreds of thousands others. Kids are being born with no hair, or teeth but otherwise normal.

TEPCO does not WANT to monitor the tanks (1)

bobeil (2821629) | 1 year,24 days | (#44668017)

Tepco tries as hard as they can to NOT LOOK how much radition is actually leaked. This is the sole purpose of having a private company rather than the Japanese state handle this accident.

The japanese government has passed a law to prevent the release of unauthorized information, especially if that information is suitable to undermine public morale. That is particularly information about radiation. This means, the government can effectively prevent panic about the meltdown from breaking out.

Tepco is the only one who is authorized to perform measurements of radiation. And they try to avoid measuring it as much as they can. They do not measure the release of radiactive isotopes that are released into the food chain. They just measure gamma radition, three feet above ground. They do not measure the amount of plutonium that has been released into the ground water.

Instead, they apparently try to contaminate the rest of the world as much as they can. Like spilling the radioactive waste into the Pacific. That enough plutonium and caesium gets into the eating fish. So that it becomes hard to prove statistically that cancer rates are higher in the vicinity of the reactor. Compared to, say, the U.S. west coast. bon appétit

Please don't panic (1)

HuguesT (84078) | 1 year,24 days | (#44668333)

I wouldn't want to work for TEPCO in Fukushima right now, however there is at this stage nobody who knows as much about the plant as they do. Whatever they are trying to do is probably not optimal, but unfortunately showering them with unsolicited, half baked advice is not improving matters.

As you know, adding more personnel and confusion to a project going badly can make things much worse. Where are we going to find competent, Japanese-speaking nuclear engineers that can actually make a positive contribution at this stage instead of diverting precious resources away from actually solving the many different, varied, complex and dangerous problems that this site has?

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