Tuesday, March 27, 2012


[Nukeblog Index]

Update: Radiation Will Fry Robots

Radiation inside the reactor 2 containment vessel at the Fukushima No. 1 nuclear plant has reached a lethal 73 sieverts per hour and any attempt to send robots in to accurately gauge the situation will require them to have greater resistance than currently available, experts said Wednesday.
Exposure to 73 sieverts for a minute would cause nausea and seven minutes would cause death within a month, Tokyo Electric Power Co. said.

"Japan reactor has fatally high radiation, no water" (Other than that, it's just peachy)

TOKYO (AP) — One of Japan's crippled nuclear reactors still has fatally high radiation levels and hardly any water to cool it, according to an internal examination Tuesday that renews doubts about the plant's stability.

The reactor cam was sent in again and ...

The data collected from the probes showed the damage from the disaster was so severe, the plant operator will have to develop special equipment and technology to tolerate the harsh environment and decommission the plant, a process expected to last decades. (I would never have guessed that)

How bad is the radiation??

"detected radiation levels up to 10 times the fatal dose inside the chamber.. radiation levels up to dangerously high 70 sieverts per hour"

1 SV is enough to nearly kill you. 10 SV/hr will definitely kill you. 70 SV/hr will probably cook you faster than a hot dog in a microwave. Water in a reactor provides two functions, one is that it is coolant. The other is that it SHIELDS RADIATION. If there is no water,there is no shield. That is why hot spent fuel has to be removed and transported UNDER WATER. There is no known way to safely clean up the pile of nuke-cr*p short of using an excavation bucket. At least at Three Mile Island it was still covered in water. They haven’t even started to clean up Chernobyl. The big reason I am now against nuclear power is that it’s fine and safe AS LONG AS IT DOESN’T MELT DOWN AND NEVER MELTS DOWN. 

This is a mess nobody bargained for, and can’t afford if there is ANY possibility of it happening again, none of this “we don’t anticipate more than one serious accident in a zillion reactor hours” nonsense. We’ve had 3 serious accidents in 30 years (Three Mile Island, Chernobyl, and Fukushima) when it was supposed to be zero in 200 years when they designed and got approval for these things. Two boo-boos have converted the surrounding REGION into an economic wasteland until hell freezes over. 

As Uncle Arnie Gundersen says (and I don’t always agree with him or anti-American networks like Russia Today that he shows up on) it’s clean economical energy when it works, but it can destroy a nation when it blows up. The pro-nuclear people are right when they point out nobody has died from radiation this time (I’ll dispute that later, even so, first year maybe-cases still aren’t beyond a dozen or so) we’re better off dying the old fashioned way with pipeline explosions, smog and fires. At least they don’t convert entire states into no-entry zones, and force residents of cities like Tokyo to patrol their neighborhoods and supermarkets with geiger counters to find hotspots (trace amounts of Fukushima radiation were measured in milk, grass, and meat in !@#$% Europe, let alone the US west coast for a few weeks) and post youtube videos of what they find.

"It's extremely high," he said, adding that an endoscope would last only 14 hours in that condition. "We have to develop equipment that can tolerate high radiation" when locating and removing melted fuel during the decommissioning.

Good grief, if an endoscope gets fried in 14 hours, a person would get fried in 14 seconds. And instead of 30 meters of water they declared December, it's only two feet from the bottom of the CONTAINMENT VESSEL, not just the RPV pressure vessel which is supposed to hold the water and fuel.

Water level is LESS than the rad line at the bottom of the gray bulb. Water is supposed to  FILL the pink  pressure verssel.

That means the whole works is basically dry, as melted fuel is probably a pile much higher than 2 feet from the bottom of the "lightbulb" containment. Fortunately the fuel has cooled down a bit because the water is 50C (122F) which still halfway to boiling. Thing is, No. 2 if anything is in the BEST shape of the 3 melted reactors:

Photo supplied by simplyinfo.org from TEPCO shows view fro m side hatch into containment floor under the ruined  reactor pressure vessel. Note duct tape and baling wire used to secure the pipes which appear to be made out of PVC not steel. 2 feet of water probably won't even cover the pile of corium (melted fuel) on the floor.

Three Dai-ichi reactors had meltdowns, but the No. 2 reactor is the only one that has been examined because radiation levels inside the reactor building are relatively low and its container is designed with a convenient slot to send in the endoscope.

Conditions at the other two reactors? "still unknown."

The high radiation levels inside the No. 2 reactor's chamber mean it's inaccessible to the workers

Heck at 72 SV per hour, there aren't any machines that will work there or won't become radioactive itself in short ordder

Good news? "parts of the reactor building are accessible for a few minutes at a time — with the workers wearing full protection."

More good news, they seem to have gotten leaks slight under control:

Radioactive water had leaked into the ocean several times already.
Workers found the fresh leak of 120 tons from a water treatment unit this week from one of its hoses, with estimated 80 liters (20 gallons) escaping into the ocean, Matsumoto said. Officials are still investigating its impact.

Japan hasn't passed a law banning nuclear power, but it looks like the point is moot:

All but one of Japan's 54 reactors are now offline, with the last one scheduled to stop in early May.

Here is what the camera saw, including running water: 

Result of the second investigation inside of Primary Containment Vessels, Unit 2(

Uploaded by  on Mar 27, 2012
【Movie】 Result of the second investigation inside of Primary Containment Vessels, Unit 2, Fukushima Daiichi Nuclear Power Plant
upload-date 27th march 2012

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