Grey smoke from No.3 reactor subsided

[FBaggins]

The grey smoke seen coming from the troubled No.3 reactor of the Fukushima Daiichi nuclear power plant on Monday afternoon has subsided. The government's nuclear safety agency said the smoke, which turned black and grey, subsided about 2 hours later.

The smoke was apparently coming from the south edge of the reactor structure. The storage pool for spent nuclear fuel is located in the southeast part of the structure.

Radiation levels at a spot about 500 meters northwest of the reactor were 2,015 microsieverts per hour, almost unchanged from the figure measured before the smoke was seen.

Smoke was also seen rising from another troubled reactor Monday evening. The government's nuclear safety agency says it was informed that white smoke was apparently coming from a crack in the roof of the No.2 reactor structure at 6:20 PM. Similar white smoke had been seen rising from the reactor previously.

http://www3.nhk.or.jp/daily/english/21_h30.html

[aquart]

1. They said the white smoke was steam.

But they still haven't a clue what the grey smoke was?

[FBaggins]

2. So it seems. But I haven't read of any firefighting efforts.

If the smoke died out on its own, it isn't the fuel pool.

[ReturnoftheDjedi]

3. keep juggling, Frodo. They don't know where the smoke is coming from.

Doesn't that trouble you?

[FBaggins]

4. If it stops on its own?

Do you think a dry fuel pool that catches fire is going to just stop burning?

I don't have the foggiest idea what the source of the fire it, and that is a concern. I do know that there's lots of damage to the building. It wouldn't be unheard of to have a fire.

[ReturnoftheDjedi]

5. why would a normal fire cause a radiation spike?

that's right, it wouldn't.

The smoke is from either the pool or the reactor.

[FBaggins]

6. Why would a fuel fire have radiation levels drop back down?

That's right, it wouldn't.

Anything that disturbs dust from inside the building is likely to kick out some radiation. That "spike" wasn't much of a spike.

And that's the telling factor. A fuel fire would have a REAL spike. Something that couldn't be argued.