Radiation Levels Surge Outside Two Nuclear Plants in Japan

[JohnSmith2007 353]

Radiation Levels Surge Outside Two Nuclear Plants in Japan

– Japan declared states of emergency for five nuclear reactors at two power plants after the units lost cooling ability in the aftermath of Friday's powerful earthquake. Thousands of residents were evacuated as workers struggled to get the reactors under control to prevent meltdowns.

Operators at the Fukushima Daiichi plant's Unit 1 scrambled ferociously to tamp down heat and pressure inside the reactor after the 8.9 magnitude quake and the tsunami that followed cut off electricity to the site and disabled emergency generators, knocking out the main cooling system.

Some 3,000 people within two miles of the plant were urged to leave their homes, but the evacuation zone was more than tripled to 6.2 miles after authorities detected eight times the normal radiation levels outside the facility and 1,000 times normal inside Unit 1's control room.

The government declared a state of emergency at the Daiichi unit -- the first at a nuclear plant in Japan's history. But hours later, the Tokyo Electric Power Co., which operates the six-reactor Daiichi site, announced that it had lost cooling ability at a second reactor there and three units at its nearby Fukushima Daini site.

The government quickly declared states of emergency for those units, too, and thousands of residents near Fukushima Daini also were told to leave.

Japan's nuclear safety agency said the situation was most dire at Fukushima Daiichi's Unit 1, where pressure had risen to twice what is consider the normal level. The International Atomic Energy Agency said in a statement that diesel generators that normally would have kept cooling systems running at Fukushima Daiichi had been disabled by tsunami flooding.

Officials at the Daiichi facility began venting radioactive vapors from the unit to relieve pressure inside the reactor case. The loss of electricity had delayed that effort for several hours.

Plant workers there labored to cool down the reactor core, but there was no prospect for immediate success. They were temporarily cooling the reactor with a secondary system, but it wasn't working as well as the primary one, according to Yuji Kakizaki, an official at the Japanese nuclear safety agency.

Even once a reactor is shut down, radioactive byproducts give off heat that can ultimately produce volatile hydrogen gas, melt radioactive fuel, or even breach the containment building in a full meltdown belching radioactivity into the surroundings, according to technical and government authorities.

Despite plans for the intentional release of radioactivity, Chief Cabinet Secretary Yukio Edano said the 40-year-old plant was not leaking radiation.

"With evacuation in place and the ocean-bound wind, we can ensure the safety," Edano said at a televised news conference early Saturday.

It was unclear if the elevation of radioactivity around the reactor was known at the time he spoke.

The outside measurement of radiation at Daiichi was far below the allowed limit for a year, other officials said, reporting that it would take 70 days standing at the gate to reach the yearly limit.

Dr. Irwin Redlener, a pediatrician who runs a disaster preparedness institute at Columbia University, said the reported level of radiation outside the plant would not pose an immediate danger, though it could lift the rate of thyroid cancer in a population over time.

However, he called the reported level inside the plant extraordinarily high, raising a concern about acute health effects. "I would personally absolutely not want to be inside," he said.

While the condition of the reactor cores was of utmost concern, Tokyo Electric Power Co. also warned of power shortages and an "extremely challenging situation in power supply for a while."

The Daiichi site is located in Onahama city, about 170 miles northeast of Tokyo. The 460-megawatt Unit 1 began operating in 1971 and is the oldest at the site. It is a boiling water reactor that drives the turbine with radioactive water, unlike pressurized water reactors usually found in the United States. Japanese regulators decided in February to allow it to run another 10 years.

The temperature inside the reactor wasn't reported, but Japanese regulators said it wasn't dropping as quickly as they wanted.

Kakizaki, the safety agency official, said the emergency cooling system is intact and could kick in as a last line of defense. "That's as a last resort, and we have not reached that stage yet," he added.

Defense Ministry official Ippo Maeyama said dozens of troops trained for chemical disasters had been dispatched to the plant in case of a radiation leak, along with four vehicles designed for use in atomic, biological and chemical warfare.

Technical experts said the plant would presumably have hours, but probably not days, to try to stabilize things.

Leonard S. Spector, director of the Washington office of the James Martin Center for Nonproliferation Studies, said loss of coolant is the most serious type of accident at a nuclear power plant.

"They are busy trying to get coolant to the core area," said Neil Sheehan, a spokesman for the U.S. Nuclear Regulatory Commission. "The big thing is trying to get power to the cooling systems."

High-pressure pumps can temporarily cool a reactor in this state with battery power, even when electricity is down, according to Arnold Gundersen, a nuclear engineer who used to work in the U.S. nuclear industry. They can open and close relief valves needed to control pressure. Batteries would go dead within hours but could be replaced.

The IAEA said "mobile electricity supplies" had arrived at the Daiichi plant. It wasn't clear if they were generators or batteries.

It also was not immediately clear how closely the reactor had moved toward dangerous pressure or temperature levels. If temperatures were to keep rising to more than 2,000 degrees Fahrenheit, it could set off a chemical reaction that begins to embrittle the metallic zirconium that sheathes the radioactive uranium fuel.

That reaction releases hydrogen, which can explode when cooling water finally floods back into the reactor. That was also concern for a time during the 1979 Three Mile Island accident in Pennsylvania.

If the reactor temperature keeps reaches around 4,000 degrees, the fuel could melt outright, and the reactor could slump right into the bottom of the containment building in a partial meltdown. Then the crucial question would be whether the building would stay intact.

"The last line of defense is that containment -- and that's got to hold," Gundersen said. If it doesn't, the radioactive load inside the reactor can pour out into the surroundings.

The plant is just south of the Miyagi prefecture, which was the region hardest hit by the quake. A fire broke out at another nuclear plant in that area in a turbine building at one of the Onagawa power reactors. Smoke poured from the building, but the fire was put out. Turbine buildings of such boiling water reactors, though separate from the reactor, do contain radioactive water, but at much lower levels than inside the reactor. A water leak was reported in another Onagawa reactor.

No radioactive releases were reported in any of the other affected plants.

As Japan is one of the most seismically active nations in the world, it has strict sets of regulations designed to limit the impact of quakes on nuclear power plants. These standards call for constructing plants on solid bedrock to reduce shaking.

As one of the most seismically active countries in the world, Japan has strict sets of regulations designed to limit the impact of quakes on nuclear power plants. These standards call for building plants on solid bedrock to reduce shaking.

Even so, 10 of Japan's 54 commercial reactors were shut down because of the quake, and Tokyo Electric Power said it had to reduce power generation. Japan gets about 30 percent of its electricity from nuclear power.

http://www.foxnews.com/world/2011/03/11/japan-issues-emergency-nuke-plant-leak/

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Seismically active areas that are heavily reliant on nukular energy. Who's bright idea was that?

[JohnSmith2007 353]

Seismically active areas that are heavily reliant on nukular energy. Who's bright idea was that?

It may have not been to bright but since they import 100% of their fossil fuels I guess they thought they needed to take a chance. I am surprised that they didn't require a more robust emergency reaction plan though.

[Ban Hammer 13,334]

Seismically active areas that are heavily reliant on nukular energy. Who's bright idea was that?

i suspect a concrete building surrounding the generators would have solved this issue in the first place.

[one...two...tree 2,762]

It may have not been to bright but since they import 100% of their fossil fuels I guess they thought they needed to take a chance. I am surprised that they didn't require a more robust emergency reaction plan though.

When you say 'they', you mean guvmint obviously.

[Hilarious Clinton 452]

I've read some bad info in many stories. Most reporters have no clue as to what the terms even mean.

I heard the diesel generators didn't come on to provide backup power. This BWR has a torus or suppression pool to get rid of the decay heat. All is not lost. I prefer a PWR over a BWR but it ain't my plant.

look at this nonsense story:

US rushing coolant to power plant in Japan after 8.9 quake

Continue reading on Examiner.com: US rushing coolant to power plant in Japan after 8.9 quake: Oil refinery on fire - National World News | Examiner.com http://www.examiner.com/world-news-in-national/us-rushing-coolant-to-power-plant-japan-after-8-9-quake-oil-refinery-on-fire-1#ixzz1GM3X9XTE

the coolant is water....... trust me they have plenty. they have the ocean if need be. we aren't sending 'coolant'. what a joke.

[^_^ 5,021]

i suspect a concrete building surrounding the generators would have solved this issue in the first place.

Containment buildings? Aren't those standard?

Actually let me google this.

Business Week:

Lack of adequate cooling for a reactor may cause a core meltdown, the most dangerous kind of nuclear power accident, according to the U.S. Nuclear Regulatory Commission.

A meltdown could potentially breach a reactor’s containment building, releasing massive amounts of radiation, according to information on the agency’s website.

Vancouver Sun:

Officials are now considering releasing some radiation to relieve pressure in the containment at the Daiichi plant and are also considering releasing pressure at Daini, signs that difficulties are mounting. Such a release has only occurred once in U.S. history, at Three Mile Island.

"(It's) a sign that the Japanese are pulling out all the stops they can to prevent this accident from developing into a core melt and also prevent it from causing a breach of the containment (system) from the pressure that is building up inside the core because of excess heat," said Mark Hibbs, a nuclear expert at the Carnegie Endowment for International Peace.

...

While there has not been any indication of damage that would undermine the building's ability to contain the pressure and allow radioactivity to leak out, there is a danger that if pressure builds too much then the walls could be breached.

the coolant is water....... trust me they have plenty. they have the ocean if need be. we aren't sending 'coolant'. what a joke.

So what do you think was actually sent? If you had to guess.

[^_^ 5,021]

Reuters:

(Reuters) - The U.S. military did not provide any coolant for a Japanese nuclear plant affected by a massive earthquake on Friday, U.S. officials said.

U.S. Secretary of State Hillary Clinton earlier had said that U.S. Air Force "assets" had delivered "some really important coolant" to a Japanese nuclear power plant.

One U.S. official said he believed Clinton was told Japan had requested the material, that the United States had agreed to provide it, and that an operation to do so was under way.

Ultimately, however, Japan did not need assistance from the United States but Clinton did not appear to have been updated before she made her public remarks.

"We understand that ultimately the Japanese government handled the situation on its own," said another U.S. official, who spoke on condition of anonymity.

[JohnSmith2007 353]

When you say 'they', you mean guvmint obviously.

When it comes to nuclear power plants I am all for government safety regulations.

[Ban Hammer 13,334]

So what do you think was actually sent? If you had to guess.

another tsunami?

[Hilarious Clinton 452]

So what do you think was actually sent? If you had to guess.

Possible boron to add to water to inject into the water. Boron will absorb neutrons and shut down the chain reaction. Boron injection.

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V4D-4NPHMYV-3&_user=10&_coverDate=11%2F30%2F2007&_rdoc=1&_fmt=high&_orig=gateway&_origin=gateway&_sort=d&_docanchor=&view=c&_searchStrId=1676104070&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=6a732b67570417569b4c7957cfab31a1&searchtype=a

I'm also seeing stories of workers being exposed to radiation. Duh..... they work at a nuke plant. I'm exposed every day myself.

[Hilarious Clinton 452]

here's a theory from a member on job related board I'm on.

"Well, here goes my two cents. At one point the water level in the core dropped to about 1.5 feet below top of active fuel (according to bbc news site I believe), not sure how long they were there. Relief valves, Iso condensers, coupled with RCIC and any other available systems removed heat initially then were unable to (100 C). Not just removing heat any relief valve operations would have moved any H2 produced in the core into the drywell. Yes the drywell is inerted but H2 still accumulates and if there is some fuel damage, which seems probable for lots of reasons, continued H2 production even AFTER filling above top of active fuel could have occurred. Anyway, all this H2 combined with exceeding the design pressure of containment (based on another report that drywell pressure had exceeded 87 pounds - they gave it in bars but you get the idea) causes H2 to leak out into the reactor building through pump seals, drywell head, and any other minute crack or crevice. No ventilation in the Reactor Building due to no power allows the H2 to collect at the highest point - the refuel floor. This is a huge volume that could accommodate a lot of H2 over several hours. Another earthquake/aftershock and a spark on the refuel floor due to metal on metal or whatever and... you get the horrific video. Yes, I agree with Mike, the refuel floor almost certainly would have had blowout panels, the video sure implies it.

Well, that's my theory - as good as any other conjecture I suppose. XF"

they have a japan thread

http://www.nukeworker.com/forum/index.php/topic,26998.0.html