We need to have a serious discussion on nuclear reactors

Paradoxical

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Fri Mar-11-11 09:36 PM
Original message

We need to have a serious discussion on nuclear reactors

Edited on Fri Mar-11-11 09:39 PM by Paradoxical

This place is jumping through the roof. I'm seeing posts suggesting that this:

A. Could be worse than Chernobyl

B. Any radioactive discharge from the plants will blow directly over the US.

Chernobyl occurred for a number of reasons that cannot physically occur in these Japanese reactors. First off, the reactor building at Chernobyl did not have containment domes over the reactor cores. These containment domes are made of steel reinforced concrete several meters thick and can withstand a direct impact from a passenger aircraft. Second, from all that has been reported, the reactors are not suffering from a runaway reaction. At Chernobyl, the reactor suffered from a power excursion. Which is essentially a fast acting runaway nuclear reaction. It caused the remaining coolant in the reactor to flash into vapor. This happened over a a very short period of time (less than a second). And the core literally exploded into a million pieces. Without a containment dome, the explosion blew the top off of the reactor building. Exposing the reactor to the open air. Chunks of radioactive control rods rained down on the adjoining town.

What's currently reported to be happening at the Japanese plant is the overheating of the core. This is not due to a runaway reaction. It's because the pumps that flush the core with fresh coolant are currently not functioning. Even after control rods are inserted into the core, the core itself will continue to generate heat.

There is no reason to believe that the reactors at the Japanese plant will suffer from any sort of rapid runaway reaction. So there will be no explosion. And even if there was, the containment dome would stop the material from reaching the open air.

What is at risk of occurring at these Japanese plants is the melting of the reactor core. Even if the reactor core melted, it would not expose the reactor to the open air.

So why are there readings of higher than average levels of radioactivity in the plant and surrounding it? When the coolant pumps stop, the coolant will increase in temperature and thus increase in pressure. At a certain pressure, emergency valves will automatically open and dump the steam into a contained area within the building in order to decrease coolant pressure. This will cause contamination in the secondary barrier. But it does not necessarily mean that any radioactive material will exit into the open atmosphere. Hence, readings inside the building are reaching what has been reported as "1000 times" the normal levels. Now, if the readings around the plant are accurate, some radioactive material must have been discharged into the open air.

But even if that is true, the amount of material released is EXTREMELY small. And as wind or water picks up that material it will dilute it to the point where anyone at any measurable distance will receive a negligible amount of exposure to ionizing radiation. Over the distance of the Pacific ocean, any material will be greatly dispersed. To the point where it will have no impact on the health of American citizens.