It is your magazine, “Discover” that I was referring to.

Thanks

Go and buy April’s Discovery magazine, go to page 56 and read about airborne pollutants that travel from China to the US in four days. It is this website’s own authors.

Concise and disturbing…

“did technicians at some point take water from the pond for use in reactor 4′s cooling system?”
http://www.bbc.co.uk/news/science-environment-12762608

(Sry, for the external plug)

“Well, that explains it then. The BWRs always were a bit twitchy. That could never happen now…”

http://www.salon.com/news/politics/war_room/2011/03/15/josef_oehmen_nuclear_not_worried_viral/index.html

(Place Aliens Quote here)

as everyone here in LA is salivating in panic over this, they dont stop to think of the thousands of gallons of oil, tons of trash and tons of soot that are expelled onto the roads (then waterways to the sea), sidewalks, streets and air each day, and what daily impact that has on their health and that of the nation.

one of the commenters here sniffed how he is “so tired” of reading about the alarmism in the press. well, nobody wants to be alarmist. but i, for one, am equally tired of you pseudo scientific snobs poo-poo-ing any and all discussion of potential worst-case scenarios. and, as the news in the last several hours reveals, you all have been proved wrong. things are getting much, much worse.

so maybe it’s time to redraft that silly headline?

just sayin’

The reactors will shut down with small releases of some radioactive material, but nothing major, and these will rapidly be diluted and much of them will decay in relatively short order.
Much more nuclear material was released during open air bomb tests.

It’s not the end of the world, people.

“A THIRD explosion in four days has shaken Japan’s earthquake-damaged Fukushima nuclear plant, as authorities struggle to prevent a catastrophic release of radiation.

Japan’s nuclear safety agency said an explosion was heard today at Fukushima’s No 2 reactor, where it was revealed last night that fuel rods had become fully exposed, sparking fears of a new blast.

The explosion, reported at 6:10am local time (8.10am AEDT), was the latest in an alarming build-up of events at the No 2 reactor, now the main focus of Japan’s nuclear safety crisis.

The evolving emergency has cast a shadow over the efforts of the government to provide relief in the country’s northeat, where the death toll from Friday’s massive quake and ensuing tsunami is expected to exceed 10,000.

Today’s explosion was feared to have damaged the reactor’s pressure-suppression system, the Nuclear and Industrial Safety Agency said, citing information from operator Tokyo Electric Power Co. [that's the "torus" and explains the "hole in the bottom" reported earlier--hr]

Radiation levels at the plant rose quickly again following the reported explosion and the agency said it was concerned radioactive material might be leaking from the reactor.

TEPCO was reported to be evacuating workers from the Fukushima nuclear plants.

Chief Cabinet Secretary Yukio Edano told reporters there had been no sudden jump in radiation indicators.

However Kyodo News reported that higher radiation levels had been recorded today in a region north of Tokyo following this morning’s blast.

Earlier today Mr Edano said the reactor’s containment vessel might have been damaged, raising the risk of uncontrolled radiation release.

A defect had been detected in the vessel, he told reporters, and the reactor “was not necessarily in a stable condition”.

Separately, a NISA official said the suppression pool under the reactor core, which holds spent fuel rods, might have been damaged.

Fuel rods in the No 2 reactor, now the most seriously worrying of the three reactor units damaged by Friday’s magnitude 9,0 earthquake, became exposed for a second time early this morning.

TEPCO began trying to pump seawater back into the damaged reactor core about 3am but the pressure build-up within was making pumping difficult.

At one stage late last night, after the four-metre fuel rods were fully exposed and apparently began melting, radiation levels at the plant reached 3,130 microseiverts hourly, six times the allowable limit.

Earlier yesterday there was an explosion in the No.3 reactor building, apparently caused by hydrogen build-up, but authorities said the containment vessel had not been breached. There was a similar explosion at the No 1 reactor on Saturday…..”

“US ships in Japan reposition as 17 crew members exposed to radiation
9 hours ago
… ships and aircraft away from the quake-damaged Fukushima Dai-Ichi Nuclear … The aircraft carrier was operating about 100 miles northeast of the power …”

In fact, we only know figures the Japanese government chooses to make public. Perhaps the author of this article can visit the nuclear plants and take his/her own measurements to back up his theory. After all, radiation leakages at these sites are overblown, and governments never withhold information from the public.

At Fukushima Daiichi unit 3, the explosion was an indicator of serious problems inside the reactor core.

Victor Gilinsky, a former commissioner at the Nuclear Regulatory Commission, said that to produce hydrogen, temperatures in the reactor core had to be well over 2,000 degrees and as high as 4,000 degrees Fahrenheit. He said a substantial amount of fuel had to be exposed at least at some point.

The Fukushima Daiichi unit 3 was built by Toshiba. Last year, the unit began using some reprocessed fuel known as “mox,” a mixture of plutonium oxide and uranium oxide, produced from recycled material from nuclear weapons as part of a program known as “from megatons to megawatts.” Anti-nuclear activists have called mox more unsafe than enriched uranium. If it escapes the reactor, plutonium even in small quantities can have much graver consequences on human health and the local environment for countless years, much longer than other radioactive materials

The steam + hydrogen is in the reactor core, and is then released from the core into the reactor containment building (so it is outside the core). It would be very mildy radioactive from reaction of elements in seawater while they were in the reactor. From what I read, not enough to harm anyone when vented outside the building, most likely, but certainly very measureable. But they had to use seawater, because the traditional cooling pumps with de-ionized water failed for multiple different reasons (this will all get hashed out later).

Normally, the water they use is deionized water, very clean ordinary water, which contains no salts, like sea or tap water does. So there is nothing to get radioactive, even as it bathes the core. Venting de-ionized water steam releases, mostly, small amount of tritium. This isn’t concerning. In a normally working reactor, such water is kept in a closed loop, and not exposed to the environment. It enters the core, cools the reactor, exits the core, is cooled in a cooling loop, then goes back into the reactor again. This looping-cycle failed, when the backup generators to run this pumping and cooling cycle failed (plus it may have failed for other reasons).

More seriously, because the core was uncovered, the rods’ coating and fuel may have melted, which means that when they circulate the sea water within the cores, and vent the steam from it, more concerning radio-isotopes of uranium and its fission byproducts may be released.

Even more seriously, there are reports that they are still having trouble pumping seawater into the reactors at a high enough rate to keep the cores covered until they cool down. Due to pressure (pumping into a high pressure vessel is hard) and due to possible earthquake/tsunami/hydrogen-explosion damage.

As long as they are able to get water to cool the reactor, a full meltdown will not happen. The pressure vessel is also built to contain a meltdown. So whatever happens, release of truly harmful amounts of radiation into the environment are not likely.

Also, because the situation is happening slowly, it may be possible to mitigate a meltdown, should it occur, by working outside the containment vessel.

The pool may have been damaged in the earthquake, the hydrogen explosion, or the subsequent collapse of the roof structure. Unit3 is especially vulnerable as it experienced a more powerful hydrogen explosion which damaged the outer walls directly adjacent to the spent fuel pools.

This is far from over.

Thanks!