Carnival of Nuclear Energy 46

1. Rod Adams at Atomic Insights provides a summary of the Fukushima Nuclear Accident from Murray Miles.

Murray Miles happens to know something about these Japanese plants. Oyster Creek on Barnegat Bay in New Jersey went on line one year before the number one Fukushima Daiichi plant and has the same design. He worked there for 20 years, and was a member of their President’s nuclear safety board.

Murray provides analysis of the Fukushima plants, the spent fuel pools, radiation and the 50 mile exclusion zone requests.

These six Daiichi plants were designed for an earthquake of 8.2 on the Richter scale but the quake was a 9.0

ALL SIX PLANTS COMPLETELY SURVIVED THIS 9.0 QUAKE.

In going the extra mile to protect from earthquakes, Tokyo Electric put the electrical switchgear in the basement. So they had electrical power after the quake. However the tsunami flooded the basements, and there was no way to pump out the basement. The water obviously shorted out the circuits.

To compound the problem, they routed the wiring for the instruments in the control room through this basement switchgear. Therefore after the flooding, all six plants were without power, without emergency diesel generators, without instrument readings to tell the status of the plants, without lights. I have not seen these two disastrous design failures discussed on television

The newest units 5 and six are offset a little from the other four. In these two there are parallel electrical circuits that did not go through the basement switchgear. These two plants are OK. The reported fire in unit five was wrong. A helicopter some distance away saw the fire from unit 4 and thought it was from unit 5. Except for the psychological problem, units 5 and 6 probably could go back into operation in the not too distant future.

UNIT 4 FUEL POOL

Fukushima Daiichi has one fuel pool for each reactor and a seventh common pool that has not been in trouble. They also have some older fuel stored in dry casks perhaps a quarter of a mile away from the plants. The unit 4 fuel pool is nearly full with around 200 tons of fuel in a water tank with a capacity of around 400,000 gallons.

You need to hear one more complication in the design. The fuel pool is really two pools separated by a gate. Fuel removed from the reactor goes first into the small, upper pool which is only 20 or 25 feet deep. Later they move the fuel to the big, deep pool. There was apparently only a little fuel in this upper pool at the time of the quake.

This UPPER pool broke. The three-eighths inch steel liner is cracked and will not hold water. The concrete wall in front of this upper pool fell off. Fuel was severely damaged probably by explosion. Temperature profiles measured by helicopters show clumps of hot stuff that must be fuel scattered around the floor area. This scenario is consistent with the numerous reports of fire in unit 4.

This is a real nightmare. But the main fuel pool in unit 4 appears intact and full of water. The spread of radioactivity came fortunately from a small amount of fuel.

50 mile exclusion

The distance of fifty miles seems to be used in emergency planning only for expanding the area to measure environmental radioactivity.

This 50-mile decision must have outraged the Leaders of Japan. I presume it upset the Japanese people too. It is being used in the U. S. To demand shutting down nuclear power at Indian Point because it is 37 miles from 18 million people in New York City.

The Chairman of the Nuclear Regulatory Commission seems to have made this decision on 50 miles himself against the advice of the NRC Staff. I evaluate this very bad decision as part of the campaign by the leader of the United States Nuclear Regulatory Commission to stop nuclear power in the United States.

2.

At Idaho Samizdat – Unhappy about management of spent fuel? Blue Ribbon Commission says that applies to just about everyone. A staff report show just how mad people really are about it.

The major themes the Commission has heard to date are grouped under seven broad headings:
(1) program governance and execution;
(2) nuclear waste fee and Fund;
(3) approach to siting;
(4) reactor and fuel cycle technologies;
(5) transport of used/spent fuel and high-level wastes;
(6) storage of used/spent fuel and high-level wastes; and
(7) disposal system for highly radioactive waste.

3. Nuclear Green – The Union of Concerned Scientist’s (UCS) nuclear safety expert Ed Lyman recently claimed that Pebble Bed Reactors are unsafe because Graphite burns. A review of discussions of graphite safety suggests that Lyman’s position on graphite safety is extremely simplistic.

General Atomic says Lyman is wrong because nuclear grade graphite does not burn. It is often incorrectly assumed that the combustion behavior of graphite is similar to that of charcoal and coal.

Numerous tests and calculations have shown that it is virtually impossible to burn high-purity, nuclear-grade graphites. Graphite has been heated to white-hot temperatures (~1650°C) without incurring ignition or self-sustained combustion. After removing the heat source, the graphite cooled to room temperature. Unlike nuclear-grade graphite, charcoal and coal burn at rapid rates because:

* They contain high levels of impurities that catalyze the reaction.
* They are very porous, which provides a large internal surface area, resulting in more homogeneous oxidation.
* They generate volatile gases (e.g. methane), which react exothermically to increase temperatures.
* They form a porous ash, which allows oxygen to pass through, but reduces heat losses by conduction and radiation.
* They have lower thermal conductivity and specific heat than graphite.

Peter Kroeger of Brookhaven National Laboratory used a computer simulation to check on General Atomic’s claim. He found that if openings developed at two opposite ends of a graphite reactor containment structure, air could flow through the core, and graphite structures would burn some, but not very much, and certainly not enough to release radioactive materials embedded in the graphite.

4. Nuclear Green – Fukushima Dai-ichi: The Good, the Bad and the Ugly

The Fukushima Dai-ichi crisis is like a horror movie, in which a very bad man, the very embodiment of evil goes on and on committing evil deeds. Nothing the victims and potential victims do to stop him is in the slightest effective. Yet despite the almost the insatiable deprivations of the bad guy, almost no one dies, although the victims are quite frightened and are constantly seen running away from the bad guy and screaming in fear. Our story features the good, the bad and the ugly.

5. Nuclear Green – The Wikipedia article on Nuclear Safety appears to have been tampered with by anti-nuclear ideologues, who have made numerous and quite silly mistakes. Meanwhile, George Monbiot has taken on Greens for practicing a double standard.

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