The U.S. Nuclear Regulatory Commission studied the safety of nuclear plants in the United States. The Peach Bottom nuclear plant in Pennsylvania is not safe from a natural disaster.
The report says if a power loss occurs for a long time, fuel rods in the reactor could be damaged, releasing radioactive isotopes within two days. It is the same General Electric design as Fukushima Daiichi.
Not surprisingly, Congress told the Nuclear Regulatory Commission to double check their findings.
Thursday’s 7.4 ‘aftershock’ not only cut power to another nuclear plant, that was struggling to keep its reactors cool, now they have found more problems.
Tohoku Electric Power Company (not to be confused with Fukushima Daiichi’s Tokyo Electric Power Company), says they have discovered water leaks, and ‘blow off’ panels are damaged.
The blow off panels are part of a pressure relief system on Onagawa’s Reactor 3. The plant was using external power from three power lines, but the latest quake knocked down two of them. Tohoku Electric says they are maintaining cooling with the one power line.
Their inspections continue, and so far they are not picking up increased radiation levels.
About 300 Japanese police have begun searching for missing people, inside the 20km (12.4 miles) evacuation zone. The police are wearing protective suits.
The police are from Tokyo and Fukushima cities. They are using heavy equipment.
At least 3,900 people from Fukushima Prefecture are still missing.
Tokyo Electric Power Company officials have to back off their six day plan of injecting nitrogen into the damaged containment vessel of Reactor 1. After a full day of nitrogen injection they say pressure is increasing in the reactor. The nitrogen does seem to have counteracted the hydrogen build up.
TEPCo said the latest 7 quake did not do additional damage Fukushima Daiichi, or Fukushima DaiNi plant.
TEPCo officials say they will trying injecting nitrogen into reactors 2 & 3, since they are now showing similar problems as Reactor 1 (hydrogen gas build up).
Just before midnight, Japan time, north east Honshu got hit with the biggest “aftershock” yet, between 7.1 and 7.4.
At first there were tsunami warnings, but they were canceled when it was realized it was not the type of quake that would cause tsunami. But this latest quake puts another nuclear plant in trouble.
Onagawa nuke plant, in Miyagi Prefecture, was already struggling to keep itself cool using outside power. According to NHK this latest quake cut three of the two power lines running to the plant. There are some confusing reports as to how the plant is keeping its reactors cool; NHK says Onagawa is using power from one external electrical line. Reuters says Onagawa is running off back up generators.
The Japanese Nuclear and Industrial Safety Agency is rushing to confirm the status of the plant.
“The Fukushima No. 1 plant was a practice course for Toshiba and Hitachi Ltd. to learn about GE’s design on a trial-and-error basis.”-former TEPCo executive
asahi.com reporting that Fukushima Daiichi (aka Number 1 Plant) was designed as “trial and error” experiment. This might explain why it’s neighbor, Fukushima DaiNi (aka Number 2 Plant), is not having the same problems.
Tokyo Electric Power Company officials recently compared the design plans of the two plants. Their conclusion was that the safety features of Fukushima Daiichi are so different, and weaker, than Fukushima DaiNi, that it must be the reason for the current crisis. I find it amazing that TEPCo didn’t already understand the fundamental differences between their nuclear plants.
A former TEPCo engineer said even upgrades, made to Number 1 Plant, were not sufficient: “First of all, there was the judgment that the reactor core buildings were in a safe location in relation to the expected height of any tsunami that might strike the plant. However, even if they wanted to move the generators, there was no space within the reactor building, so that would have meant a major revision in design. At the time, no one considered making such changes.”
A unnamed midlevel TEPCo official said just getting a nuke plant built was all that mattered: “The blueprints for the reactor cores at the No. 1 plant were bought ‘as is’ by Toshiba Corp. from General Electric Co., so the priority at that time was on constructing the reactors according to those blueprints.”
Remember, there are six reactors at Fukushima Number 1 Plant. So far reactors 1, 2, 3 & 4 are in trouble. Why not reactors 5 & 6? Those reactors are of a later more improved design than the 1, 2, 3 & 4 reactors.
Some TEPCo officials admit that making the decision NOT to make proper improvements was a matter of pride; it would have meant admitting that the work already done was faulty.
General Electric’s current involvement in the crisis might be due to the fact that they could be sued, under Japanese law, for their faulty design.
The following is from Kyodo News.
Radioactive iodine-131 has a half-life of eight days, meaning that its effect will be reduced to half in eight days, one-fourth in 16 days and one-sixteenth in 32 days.
Half life for cesium-137 is 30 years.
A Tokyo Electric Power Company employee refused to reveal how much radiation he’s been exposed to in the past three and a half weeks.
”I can’t tell you. It’s private information as well.”-Murata Yasuki
Recently Murata was allowed to take one day off to visit his wife and son.
Workers at the critical Fukushima Daiichi plant live in a building designed to withstand a 7.0 quake. It is also lead lined, but workers there say the radiation shielding has been compromised.
Tokyo Electric Power Company says there are signs that the injection of nitrogen into Reactor 1 is working to prevent an explosion. But it might be too soon to tell, the nitrogen injection operation will take six days.
Fukushima Daiichi’s Reactor 1 core began build up of hydrogen gas, probably caused by the melting of the outer casing of partially exposed fuel rods. In normal circumstances reactor cores have nitrogen in them to counteract any hydrogen build up, but TEPCo officials think Reactor 1’s core is breached, leaking out the nitrogen.
If that’s true then the six day nitrogen injection operation could be only temporary.
NHK interviewed a nuclear analyst, who pointed out that just because contamination readings are within safe limits does not mean that it’s ‘OK’.
He said officials are mistaken for telling people that it does not pose a threat to health. What it means is that you must begin “…limiting your exposure…” to radiation contamination, because it builds up in your body, it doesn’t go away.
It is referred to as cumulative exposure to radiation.