The WordPress.com stats helper monkeys prepared a 2011 annual report for this blog.
Here’s an excerpt:
The concert hall at the Syndey Opera House holds 2,700 people. This blog was viewed about 18,000 times in 2011. If it were a concert at Sydney Opera House, it would take about 7 sold-out performances for that many people to see it.
TVA loses all power transmission lines in Alabama and Mississippi, Browns Ferry Nuclear plant forced into emergency shutdown
Wednesday’s storms took out all of TVA’s electric power transmission lines in Mississippi and North Alabama, and forced Browns Ferry Nuclear Plant onto diesel backup power and into emergency and automatic cold shutdown.
Bill McCollum, the chief operating officer of Tennessee Valley Authority, said it may be weeks before power can be restored to all of the 300,000 customers whose power is supplied by the federal utility.
“With the level of damage we have, it will be — we hope it will be days until we get most of the customers back on, but it will be weeks before we’ve fully repaired all of the damage,” he said.
McCollum said the reactors, now being cooled by backup diesel power, are safe. He also said the spent fuel pools also are being cooled by backup diesel power and are safe.
The transmission lines are the monster power lines that carry electricity from TVA power plants to power distributors such as EPB and Huntsville Utilities.
Now those utilities, along with a number of large industries that are wired directly to TVA transmission lines, will not have power until the lines are repaired, McCollum said.
The loss of those transmission lines also caused Browns Ferry Nuclear Plant to lose power.
When the plant generates power, it uses some of that power and the excess is sent out on the transmission lines. When those transmission lines can’t take power, it causes the reactors to trip, according to TVA officials.
The spent fuel is not as well protected as the fuel in the reactor. In Japan, the spent fuel is now open to the atmosphere in at least two plants. The danger posed by the pools is significant. A U.S. study showed that a drained spent-fuel pool delivers a lethal dose of radiation to a worker at its railing in 16 seconds.
Fuel rods in the pool are thermally hot and radioactive. They rely on water and circulation pumps to avoid reaching temperatures that melt the metal cladding around the fuel rods, a condition that releases radiation.
Browns Ferry is more vulnerable to problems with the spent-fuel pools than are the plants in Japan. Delays in constructing a storage facility for depleted fuel — planned at Yucca Mountain in Nevada — resulted in Browns Ferry and other plants stockpiling the fuel in the cooling pools.
TVA is gradually moving the spent fuel to on-site dry casks, but the pools remain near capacity. A capacity that was increased by request of the nuclear industry resulting in closer spacing of spent rods than was originally designed into the system.
That means they have more radioactive content than the pools at the Japan reactors, and they are more dependent upon electric pumps to circulate water within the cramped quarters.
“Our spent fuel pools in the reactors like the one in Japan are almost filled to the brim, and the risk from the spent fuel pools — either from an accident or from an act of malice — are about as high as you could possibly make them,” said Lochbaum, director of the nuclear safety program at the Union of Concerned Scientists, which describes itself as a watchdog group that neither supports nor opposes nuclear power.
Another issue that some experts fear will come into play in Japan involves the consequences of melting fuel rods within the reactor.
If cooling efforts fail, the fuel rods ultimately will melt into a lava-like substance. The heat would melt the steel reactor vessel, allowing the melted fuel to drop to the concrete containment vessel. In Mark I reactors, the containment vessel is concrete with steel at the edges.
“In the Mark I containment, there is a known vulnerability to containment failure known as liner melt-through,” said Ed Lyman, a physicist at Union of Concerned Scientists. “If that melt spreads to the corners, then it may be able to melt through the steel shell of the containment as it ate through the reactor vessel.”
If it happens, especially if the containment vessels are damaged as they are in Japan, “that would essentially mean large radiological release to the environment.”
McCollum said he is confident the authority’s reactors are safe, but TVA will seek to learn from the problems in Japan.
“TVA’s plants are designed, built and operated to be safe,” McCollum said. “That’s our No. 1 mission. Our plants are designed to be very robust against all types of occurrences.
“It’s far too early to assess the total impact of this,” McCollum said. “I believe we’ll have to wait to understand the facts and events as they’ve really occurred, and what actions may need to be taken and lessons to be learned out of this.”
It has recently been reported in a number of blogs that Xe-131 has “blanketed” The US. There is enough to worry about during this event and Xenon is not one of them.
Pacific Northwest National Laboratory measured and reported the Xenon. Their lab has the most sensitive instrument in the world measuring specifically for Xenon around-the-clock. They are set up to provide Nuclear Test Treaty verification. They are not set up to warn for un-healthful levels during a radiation event.
Here is a report from the lab that first measured the very miniscule levels. PACIFIC NW LABS XENON-131 STATEMENT
Most of the “articles” include a moving map from WeatherOnline as proof of the blanket of Xe-131 covering us all. These are predictive dispersion models of where radioactive isotopes might go if they were in the atmosphere at that time. They are basically weather maps – not radiation predictors and should be treated as such.
Here is a disclaimer from the WeatherOnline website to amplify my assertion: “ATTENTION: These products are highly uncertain based on limited information for the source terms. Please use with caution and understand that the values are likely to change.”
HALF-LIFE: 5.29 days
Hazard category: C- level (low hazard ) : 0.100 to 10 mCi
B – level (Moderate hazard) : > 10 mCi to 1000 mCi
A – level (High hazard) : > greater than 1000 mCi
EXTERNAL RADIATION HAZARDS AND SHIELDING:
The gamma exposure rate at 1 cm from 1 mCi of Xe133 shielded for betas is 150 mR/hr, and at 1 foot will be 0.17 mR/hr. The half and tenth values of lead for this gamma are 0.003 and 0.015 cm respectively. This means that lead sheets or regular lead shipping pig will be sufficient for shielding the material.
The maximum range of the betas is about 0.002 inches in lead. Therefore, the use of the lead shield for storage will provide adequate shielding for the beta particles. If skin is uniformly contaminated with Xe133, 1 microcurie /cm2 deliver a dose of 4200 mrems/hr to the basal cells of the skin.
HAZARDS IF INTERNALLY DEPOSITED:
It is important to avoid ingestion, inhalation and/ or skin contamination.
The NCRP MPC for Xe133 is 10E-5 uCi/ml for 40 hr/wk.
SPECIAL PROBLEMS AND PRECAUTIONS:
1. Xe133 is heavier than air and hard to be kept in solution form, therefore, one should work in well ventilated areas.
2. Survey frequently. Change gloves often.
3. Limit of soluble waste to sewer: 100 microcuries per day per lab
Today we have received a letter of protest from National Federation of Fisheries Cooperative Associations (NFFCA) with regard to the discharge of the low level radioactive wastewater from Fukushima Daiichi Nuclear Power Station to the sea. We, as the operator of the power station, received the letter with sincerity, being painfully aware of the feelings and concerns of people in the fishery industry.
While the water discharge was an unavoidable emergency measure implemented after the consultation with the national government in order to prevent the spread of high level radioactive substances, protect the essential safety facilities from inundation and maintain the cooling functions of Units 5 and 6, we would like to make our deepest apologies for the concerns and anxieties caused by our insufficient explanation in advance.
With regard to the compensations related to the water discharge and other issues, we will follow the Act on Compensation for Nuclear Damages and sincerely address them with support from the government. We would highly appreciate it if NFFCA could understand the above.
Working closely with the government, we will make every effort toward the earliest resolution of the situation.
April 6, 2011
The Tokyo Electric Power Company, Incorporated