
Japan nuclear body says radioactive water at Fukushima an 'emergency' - yapcguy
http://preview.reuters.com/2013/8/5/fukushima-radioactive-water-likely-breached
======
marze
Anyone can correct me if I'm wrong, but I believe for two years Tepco has been
dumping about 150 tons of water a day on the melted cores at the bottom of the
reactor buildings (or wherever they are), and pumping 100 tons of it out to
filter and reuse.

Obviously, 50 tons/days has disappeared every day for 2+ years. Since that
water came in contact with the melted cores is extremely radioactive (not just
tritium). Measurements of the water filling the lower levels of turbine
buildings supports this thinking (something like 1 Seivert/hr).

Since TEPCO has not allowed any independent measurements of the ocean within
kilometers of the site, nor independent ground water measurements, and the
independent ocean measurements taken at large distance from the site do not
show a decrease in contamination vs. time, it appears likely they've been
leaking substantial amounts of cesium and other radionuclides into the ocean
for >2 years.

If so, an impressive coverup. The math is simple, water in minus water out,
and where did the missing water go.

~~~
VLM
Hmm we'll lets run this thru the engineering filter and see how much is
reasonable.

Well, something that can't run forever, stops, and its been close enough to
forever that you can assume we're evaporating away 50 tons/day. Where else
could it be going? But is that a reasonable evap rate from an engineering
perspective?

50 tons is about 50K kilograms. Takes about a KWH to boil away a kilo of water
so we're looking at about 50K KWH or 50 MWH per day. Now there's about 25
hours in a day so thats about 2 MW continuous boiling away water, or at least
on long term average.

A big reactor runs in the GW range but decay heat starts around 10% and slowly
drops over time. Actually a couple years in, most should be gone although the
long tail is pretty long. So it was dumping out tens of MW continuously and
now maybe much less. So we're looking at a couple MW generated, vs a couple MW
to make that much water vapor. Seems reasonable. So I'm willing to believe
from an engineering estimate, aside from solar heating and whatever, that 50
tons of water simply evaporates away.

We can argue volumetric, if a ton is about 1K kilos and 1 L water is about 1
Kg, that would strongly imply a ton of water is about a 1K liters or about one
cubic meter. I suppose we could have gotten to this same point by talking
about mL vs cubic centimeters vs grams. Anyway you're claiming a cube of water
a meter on a side, stacked 50 tall each day, for a couple years. I say that
most of that has to have evaporated away otherwise you'd have 50 meters deep
of water covering the entire site after a thousand or so days.

~~~
marze
All good, but there is no boiling.

Just evaporation from the surface of the pooled water flooding the buildings,
which will not be significant, even if it wasn't at a humid oceanside
location.

~~~
VLM
You're talking about a small decimal point variation in heat of vaporization
aka enthalpy of vaporization. You are correct it does in fact vary by temp,
but as a percentage, less than my vast rounding errors. One problem is heat of
vaporization usually drops with temp. So evaporating water at 400 degrees in a
boiler takes somewhat less energy than evaporating the same amount on a open
to the air pond, and there's not much of a pressure vessel around the plant
anymore anyway. For all intents and purposes given reasonable rounding the
energy required to evaporate the water is more or less constant in that
location.

This has to do with the strength of the hydrogen bond in water. The energy
require to vaporize the water is the same as hundreds of degrees of merely
heating the water, thats why the starting temp has little effect on water
boiling rate, etc.

Still I stand by my numbers, 2 MW continuously can evaporate your 50 tons of
water per day, to one sig fig.

Note that we're not arguing about much. Sunlight is like a KW per sq meter so
we're arguing about the energy from 2000 or so sq meters of sunlit area, which
isn't much compared to a giant nuclear plant facility.

It just doesn't strike me as much of an engineering challenge to evaporate 50
tons/day given that size of a facility and the decay heat and the solar
insolation.

~~~
marze
Those are some awesome calculations. Since we are talking Japan's food supply
and the Pacific Ocean, it would be nice to have some independent measurements
taken on site, in addition to your nice back-of-the-envelope calculations.

Keep in mind this water is all indoors, so unless you have some openings you
are blowing air in, there will be no evaporation whatsoever.

------
mpyne
More details would be nice. As the article notes, tritium itself is _almost_
innocuous (its decay is via a weak beta particle emission, about the only way
it could hurt you is if you ingested a lot of it).

Either way the problem with radioactive materials relates to the
_concentration_ in solution of radioactive materials more than the binary
"radioactiveness" of the material. After all the human body itself is
'radioactive' if only from the K-40 and C-14 that are present.

Without knowing the concentration of radioactive contaminants like Co-60 and
radiocesium that might leak into the sea it's hard to know how much of an
'emergency' we'd be looking at. All we'd know for sure is that TEPCO is
incompetent... but then what else is new?

~~~
ChuckMcM
It would be hugely better to actually have details.

Water, aka H2O, doesn't activate so it is not radioactive, it can however
carry radioactive isotopes in solution. Is the groundwater flowing from the
neighbouring area? (implied) then the it is carrying cesium from the
environment away (good thing if you want to move back into the neighbourhood)
is it picking up new contaminants from a broken reactor vessel?

I wonder if anyone has a better source for data here.

~~~
mpyne
Water _can_ activate (much more so than you think in fact, though I can't
discuss further maybe someone with a civilian background in nuclear physics
can fill in).

Certainly the long-term danger is more from what the water will carry in
solution than from the water itself though.

~~~
VLM
"though I can't discuss further maybe someone with a civilian background in
nuclear physics can fill in"

Oh spare us the cloak and dagger. I don't think oxygen radioactivation has
been classified for about 80 years now.

There's even a pretty good wikipedia page at

[http://en.wikipedia.org/wiki/Isotopes_of_oxygen](http://en.wikipedia.org/wiki/Isotopes_of_oxygen)

The "natural" stable isotope O-16 needs to get triple neutron activated before
you get an unstable isotope O-19 and the half life of that is like a minute.
So its about half a million minutes per year, and its been about two years, so
thats about a million half lives later... I think all the O-19 is long gone.

I do agree 100% that the "stuff" dissolved in the water is about a zillion
times more important than the oxygen itself.

Its so mainstream there's some interesting radio oxygen dating work done using
the Dole Effect, which also has a wiki page. TLDR is photosynthesis
preferentially concentrates certain O isotopes so you can make all kinds of
assumptions about glaciation and where plants are growing (ocean or land)
given some 16O:18O ratios.

[http://en.wikipedia.org/wiki/Dole_effect](http://en.wikipedia.org/wiki/Dole_effect)

There's even a cool wikipedia article with a UTF-8 name.

[http://en.wikipedia.org/wiki/%CE%9418O](http://en.wikipedia.org/wiki/%CE%9418O)

Which brings you to the greater topic of isotope geochemistry

[http://en.wikipedia.org/wiki/Isotope_geochemistry](http://en.wikipedia.org/wiki/Isotope_geochemistry)

I'm sure there is at least some cloak and dagger stuff that can't be discussed
but there's a simply huge amount of open literature about oxygen
radioactivity. I would suspect there's more open lit stuff about isotopic
geochemistry than cloak and dagger stuff.

~~~
mpyne
> Oh spare us the cloak and dagger. I don't think oxygen radioactivation has
> been classified for about 80 years now.

I'm not trying to be cloak and dagger, otherwise I wouldn't have mentioned
that a civilian trained nuclear physicist can tell you the exact answer.

However I do not have CG-RN Rev 3 completely memorized and I no longer have
access to it, so unless I know for sure something is not NNPI or otherwise
protected by the Atomic Energy Act then I don't discuss it. Not that I don't
agree that it's _pretty crazy_ that someone who's never been in the Navy could
go and look at Wikipedia and discuss it with someone else and be just fine but
that the person who's been in the nuclear Navy cannot... but then I've never
attributed "common sense" to the military.

With all that said, you haven't hit on exactly what I'm talking about (not
that oxygen activation isn't cool). I will say the actual answer is pretty
mundane, not at all cloak-and-daggery.

~~~
VLM
"Not that I don't agree that it's pretty crazy"

Well if that's how the Navy is, then that's how it is. I was MOS 55R in the
army and that's not how how we do it. Then again I was not a 55G which (was)
the nuke guys. Maybe they have excessive rules, maybe not.

As for n activation of (pure) water that either the O which is harmless or the
H which is almost too obvious or playing games with contaminants. Nobody uses
pure water as a coolant other than maybe training/experimental/university
reactors, so there's the chemical shim system (and its inevitable
contaminants). Or simple mechanical contamination like household dust
essentially. Or corrosion (however slow) of non-bulk parts of the reactor,
iron, carbon, and chromium from the walls are irrelevant but copper ions from
slowly corroding cabling or something. Good luck being nearby the ocean and
not having detectable chloride ion concentration, however low. Or dissolved
nitrogen from the air, argon etc from the air. Sealing/gasketing material
incredibly slowly corroding away. There's more to stainless steel than just
Fe/C/Cr so if you corrode enough of it... Not much other options, its a pretty
highly controlled area.

~~~
nknighthb
It's how it is with nuclear information everywhere in the US government. If
you don't _know_ that you can talk about it, you don't.

[http://en.wikipedia.org/wiki/Born_secret](http://en.wikipedia.org/wiki/Born_secret)

------
api
Fukushima converted me away from being a supporter of nuclear, or at least
conventional nuclear. _Maybe_ something like LFTR or WAMSR could re-open the
debate in my mind, but the debate for conventional solid-phase reactor cores
is pretty much closed.

Not because I buy into all the fear mongering about radiation, but for a much
simpler reason: it showed that conventional nuclear is not cost-effective vs.
the alternatives and is not scalable.

In any system, accidents will happen. Worst case accidents will happen. The
frequency may be low, but Fukushima shows that _one_ singular bad accident can
completely obliterate the economic rationale for nuclear power in a given
country. Fukushima is going to be a billions-a-year money pit for Japan for at
least the next decade and a half.

Given those costs plus the fact that nuclear without accidents is not
substantially cheaper than alternatives, it just seems more _rational_ to
invest the money and R&D effort required to solve the energy storage and
distribution problems associated with solar and wind energy.

In the end, provided we can back them up and distribute the power efficiently,
there is actually more energy available from the sun and the wind than there
is from any actionable real-world plan for scaling nuclear that I've ever
seen. Renewables also have many other benefits including:

\- Very low risk... basically no more dangerous than any other construction or
manufacturing.

\- No fuel, so little to no real sustainability concerns. This means that once
we make them work they will work forever and we won't have to worry about
energy anymore.

\- Small incremental investment cost. Wind and solar can be deployed in small
increments, and it's exponentially easier to raise small increments of money
than large ones.

\- Less politically centralized. Nuclear demands centralized regulation and
huge centralized financial control, and nuke plants are central points of
failure for the entire industrial system built around them. Were we to rely on
them exclusively they would become easy "off switches." Renewables by contrast
open up the potential for a "PC revolution" in energy.

It just seems like a no brainer for me. Nuclear is a boondoggle, at least for
most uses.

~~~
tptacek
I don't understand how an empirical analysis, such as this purports to be,
could get around the fact that "conventional" power generation kills far more
people than nuclear ever has.

~~~
marze
In deciding what to build next, you would compare nuclear with the other
future options, which do not include coal.

No one argues that solar or wind will kill anyone.

And, the real problem with nuclear is that it isn't cost effective. If the
free market was operating, no plants nuclear plants would be built in the US.
It is only with govt. subsidies making 90% the up-front cost risk-free there
has been even a nibble of interest from free market investors. And even that
interest has petered out.

~~~
neonhomer
But if the free market was truly operating would we be building any wind and
solar plants? When it comes down to it aren't coal plants still the most
economical from a market stand-point?

~~~
VladRussian2
>aren't coal plants still the most economical from a market stand-point

only in the current environment there most of the cost of coal energy (green
house gas and other pollutants emissions, environment destruction where coal
is mined, etc...) is socialized

------
brianbreslin
Has anyone done tests to see how the radioactive water and other contaminants
have affected the pacific as a whole? how about the fish stock near japan?

[http://www.grida.no/images/series/vg-
climate/large/32.jpg](http://www.grida.no/images/series/vg-
climate/large/32.jpg)

~~~
toomuchtodo
Does this mean we have to start equipping undersea seismic sensors and surface
buoys with geiger counters? :(

~~~
Bjoern
The dilution of the radioactive content by the ocean is probably high. Overall
the risk is low for significant contamination due to the overall ocean volume.

The issues are so-called hot-spots which cause certain fish to be extremely
radioactive and streams causing concentrations of radioactive materials highly
contaminating only certain regions and fish.

That being said, there are so many pollutants in the oceans that I'm confused
why people are not more outraged about ocean pollution.

Vice Documentary about garbage streams. e.g.
[https://www.youtube.com/watch?v=D41rO7mL6zM](https://www.youtube.com/watch?v=D41rO7mL6zM)

Finally, its certainly not acceptable to have on-going ocean pollution, which
is probably happening in Fukushima Daiichi.

------
carsonreinke
`Tepco's "sense of crisis is weak"`, ultimately the problem.

~~~
Bjoern
The infamous Atomic Village problem, particularly Tepco's corruption is quite
well known and paradoxically accepted by the society.

[https://www.youtube.com/watch?v=pGsYdDpUSzg](https://www.youtube.com/watch?v=pGsYdDpUSzg)

(turn on captions)

------
LolWolf
But what was leaked is really not all that much. Recall that 1Bq is a
disintegration per second, and, although a few trillion is quite a bit, this
is over a massive volume. Now, there's nothing stated in terms of how much
leaked into water sources, so, there's little judgment that can be made. But I
believe it's little to truly worry about.

