Friday, March 18, 2011

Previous Notes on the progress of the disaster at the Fukushima Daiichi Nuclear Reactor Site Through Thursday morning EDT. 

All of the plants at the Fukushima Daiichi complex are General Electric designs. They are operated by Tokyo Electric Power Company (TEPCO). Here is your scorecard (with reactor manufacturers noted) for the Fukushima Daiichi plants as they experience their unfortunate events:

Status Updated 7:30 AM 17 March 2011 EDT, Thursday night Tokyo time, monitoring NHK World TV Live in English. Further updates will be given via new blog posts.

(Via NHK) Thursday night : Casualty reports indicate over 5,500 confirmed dead in the earthquake and tsunami and over 9,600 unaccounted for.

Plant 1 July 1967-General Electric Reactor
Hydrogen gas caused outer housing explosion Saturday. Core may be in partial meltdown, estimated 70% fuel rods damaged.

Plant 2 June 1969-General Electric Reactor
core threatening to In partial melt down. Explosion early Tuesday damaged the containment system. Fuel rods were fully exposed. An estimated 33% damage to fuel rods was reported. The suppression chamber in the reactor is reported damaged.

Plant 3-December 1970-Toshiba (Westinghouse) Reactor
(uses mixed oxide Plutonium fuel and therefore is the most potentially hazardous)
Hydrogen gas caused outer housing explosion Sunday. Core may be in partial meltdown. White smoke was reported Wednesday morning. The reactor container is said to be intact but there are contradictory reports on the actual condition of the container.
(Via NHK) Thursday the water in the spent fuel pool was reported too low which caused authorities to authorize helicopter water drops despite dangerous levels of radiation. There is almost no water left in the spent fuel pool. It will require many helicopter runs. A helicopter can carry 7.5 tons of water per drop. The pool capacity is 2000 tons. It is believed that the pool can cool the spent rods if brought to a level perhaps one third full. The rate of possible leakage in the pools is unknown. Authorities have given reactor 3 first priority for cooling as of noon Thursday, Japan time. This reactor is potentially the most dangerous as it uses plutonium mixed oxide fuel. The first helicopter run was at 9:48 AM Thursday morning Japan time. Water cannon may be used on site by police. Effective range of water cannon is 30 meters. Riot police have been instructed to begin use of riot water cannon on reactor 3 as soon as possible.
Two helicopters made two drops each of 7.5 tons of seawater each from 90 meters altitude Thursday with an insignificant drop in measured radiation in the area at 3754 microsieverts per hour after the drops, measured 100 meters from plant 3. From my observation of video of these helicopters it looks like very little seawater is actually reaching the pool from these drops. Because of the risk of radiation the helicopters were unable to hover about the spent fuel pools. The had to drop the seawater while moving which spread out the water over a large area rather than the target area. Lead plates were installed underneath the helicopters to provide some protection against radiation. The extra weight is was said to hamper mobility and ability of the helicopters to carry a payload.
Five fire engines have been brought into the area to cool the spent rod piles. Police water cannon efforts to add water to the cooling pools was discontinued Thursday. Water cannons were unable to reach the pools without putting police personnel in danger of excess radiation effects.
Water sprayed or dropped into the pool seems to be vaporizing as soon as it enters the pool.
Thursday night heroic Japan Self Defense Force (SDF) personnel commenced spraying water from five fire engines into the spent fuel storage pools at plant 3 and 4. SDF personnel were able to operate the fire engines from inside the equipment helping them to avoid some radiation.
TEPCO personnel are attempting to restore high voltage electric power to the water pumps at the reactor sites. It is unknown if the pumps will operate when power is restored.
"At a certain point, they're going to have to abandon ship, they're committing a suicide mission to go in there. The radiation levels are near lethal right now…you're committing suicide to spend large amount of time there." theoretical physicist Dr. Michio Kaku said Thursday.

Plant 4-February 1973-Hitachi (General Electric) Reactor
A reported fire Tuesday morning was suppressed but fire started again on Wednesday. A possibility of drained water from spent fuel pool caused burning of exposed spent fuel rods.
US officials were quoted Thursday as saying the spent fuel pool is empty at this reactor.
The walls of this reactor have collapsed, according to a TEPCO spokesman Thursday night. Thursday night a TEPCO spokesman stated that some water was left in the spent fuel pool at reactor 4.

Plant 5-May 1972-Toshiba (Westinghouse) Reactor
There was a report Wednesday, Japan time, of low coolant pool water level causing a high temperature in the spent fuel pool. No combustion has been reported.

Plant 6-October 1973-General Electric Reactor
A report Wednesday indicated that coolant pool water level was low, causing an elevated temperature in the spent fuel pool. No combustion has been reported.

On Thursday, in cooperation with the Japanese government, a USAF Global Hawk surveillance drone plane was dispatched from Guam to take detailed photographs of the Fukushima Daiishi complex and surrounding areas damaged by the earthquake and Tsunami.

Plant 7 planned for 2016
Plant 8 planned for 2017

No one really knows what is going on inside these plants. It is too dangerous to go inside for any long period of time and monitoring equipment is probably inoperable. Actual readings of radioactivity just outside the plant seem to be a guarded secret. Only observations of smoke and structural damage can be made at this time.
Plants#4, #5 and #6 were reported shut down and under maintenance at the time of the earthquake.
General Electric and Hitachi nuclear power divisions merged (or created an "alliance") in 2007 as GE-Hitachi Nuclear Energy.
Westinghouse Electric was sold by CBS/Viacom to British Nuclear Fuels Ltd. in 1999.
In 2006 BNFL sold Westinghouse Electric to Toshiba.
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