Another Nail in the Coffin
of the Linear-No-Threshold (LNT) theory of radiation effects. A friend sent me this absolutely juicy article in which the author uses the Union of Concerned Scientists (LNT is their only reason for existence) cancer estimates against them. Here is the article.
In a nutshell, they applied the USC’s “any radiation causes cancer” methodology to airline flight where the population acquires thousands of man-REM of exposure over terrestrial background by virtue of being closer to outer space. In particular he looks at airline workers (stewardesses, pilots, etc.) According to the LNT cra… er theory, they should be dropping like flies from cancer caused by the “excess exposure”.
The most notable news today is that two workers entered the Unit 1 reactor building for the first time since the explosion. They took radiation readings and prepared for the installation of air clean-up units pictured at left. Each unit contains a charcoal bed for iodine removal and a HEPA (High Efficiency PArticulate) filter to remove fine dust. The idea is to operate these units for several days to reduce the amount of airborne radioactive material inside the plant.
The goal of this activity is to make the reactor building habitable long enough that workers can attach the necessary piping to set up a closed loop cooling system. Right now they’re operating on the “feed and bleed” system where fresh water is pumped into the reactor and then allowed to bleed out. That’s where the massive amount of contaminated water in the turbine buildings is coming from. The closed loop cooling system will recirculate the same water over and over.
Bracing the Unit 4 Fuel Pit
TEPCO is looking at the feasibility of installing a concrete and steel support under the #4 spent fuel pit to help support the earthquake-damaged pit. There is some valid concern that another strong shake could cause the pit further damage, perhaps cracking it so that could not hold water.
The image at left shows a small portion of the fuel pit taken on 04/28. One can see debris from the explosion laying on top of the fuel racks. No gross damage to the fuel is visible in this shot. This indicates to me that the fuel got hot enough to fail the cladding but not hot enough to melt. That there was a hydrogen explosion indicates that a large zircalloy/water reaction took place.
MEXT (Ministry of Education, Culture, Sports, Science and Technology) has released a massive amount of data concerning environmental radiation in the exclusion zone. This is a truly gargantuan amount of data. It would probably take a month to go through all if it. I’ve sampled some of it. It supports what I said earlier, that with the exception of a few small places such as Iitate, there is absolutely no reason to be keeping people out. Yet the government is now saying that it may be next year before people are allowed back in. Absurd.
Other than the projects mentioned above, TEPCO is working on the following activities
Removing radioactive debris from around the outside of the reactor buildings. This will allow recovery workers to work in this area without risk of excessive radiation exposure.
Construction of a desalination plant to remove the salt from the water being pumped from the turbine buildings
Pump the water in the turbine buildings into temporary storage.
Erect a demineralization plant to clean up this water so that it won’t emit so much radiation.
Further experimentation with flooding the Unit 1 containment structure to aid with cooling the reactor. No news release has said so but I’m of the impression that they’re about to give up on this, based on the concern that another strong aftershock might damage a water-filled containment. I think that the current attempt to purify the air in Unit 1, to be followed by connecting to the Reactor Coolant System with the closed loop heat exchange is the new plan.
Less Frequent Updates
Now that the emergency phase of the event is over with and the utility is settling in for the long task of recovery, there is far less information flowing from the company and the various English language news sources that I monitor. Just not that much to report. Therefore I won’t be writing these updates nearly so often. Only when something interesting happens.
Meanwhile let’s not forget about the true disaster. The quake and tsunami. The photo at left shows the utter devastation caused by the combination disaster. With the official death toll over 30,000, anything that happens at the nuclear plant is small potatoes. The media would have you believe that the nuclear plant is the center of the disaster. It isn’t. No one outside the plant boundary has been killed or even injured by the incident. Keep that in mind as you read both the major media and my reports.
Posted by neonjohn on May 5th, 2011 under Energy, Nuclear