Posted on 03/21/2011 9:53:53 PM PDT by fight_truth_decay
NEI has added a new graphic to its website: Emergency Presparedness: Protecting the Public and Environment.
UPDATE AS OF 6:30 P.M. EDT, MONDAY, MARCH 21:
Japan's NHK broadcasting network reported that Tokyo Electric Power Co. confirmed that the March 11 earthquake and tsunami were beyond the Fukushima Daiichi plant's design standards.
TEPCO believes the tsunami that inundated the Fukushima Daiichi site was 14 meters high, the network said. The design basis tsunami for the site was 5.7 meters, and the reactors and backup power sources were located 10 to 13 meters above sea level. The company reported that the maximum earthquake for which the Fukushima Daiichi plants were designed was magnitude 8. The quake that struck March 11 was magnitude 9.
Smoke seen from Fukushima Daiichi reactor 3 on Monday subsided after about two hours. Water pressure and levels at the reactor were unchanged through the episode, as were radiation levels, the company said.
The site was temporarily cleared of workers after smoke rose from at the secondary containment buildings that house reactors 2 and 3. The Nuclear and Industrial Safety Agency said the smoke from reactor 2 caused radiation levels downwind to rise for about three and a half hours.
(Excerpt) Read more at nei.cachefly.net ...
MIT NSE Nuclear Information Hub last update: March 20, 2011 9:37 pm UTC Maintained by the students of the Department of Nuclear Science and Engineering at MIT:
Fission Products and Radiation
Thanks for posting this. I’ve been looking for recent updates.
For want of a nail ...
I think over the next several months a lot of things are going to come out showing if they had just gone a little bit farther to hardening that place when they built it, none of this might have happened. But like the say, hindsight is 20-20.
Thanks for posting. This is the first time I’ve seen actual design parameters like this:
* Tsunami design basis for the site: 5.7 meters.
* Actual tsunami was 14 meters.
* Backup power sources located 10 to 13 meters ASL.
So the designers took the worst-case tsunami and then doubled the height of the backup generators. But the biggest tsunami in all recorded Japanese history swamped even that.
A conservative hazard review process has a generous safety factor. It does not appear that such a standard was applied here.
I bet they wish they had!
I wonder about those numbers - wouldn’t the projected tsunami height be stated as above sea level? 5.7 meters above sea level? And then the designers put the backup power 10 to 13 feet above sea level?
It says 10 to 13 meters - not feet.
Somewhat like the levee’s in New Orleans (on a micro scale)
The plant was designed for M8 and handled M9 just fine. The tsunami swamped the emergency generators needed for cooling after the plant went dark. They needed the additional safety factor on the emergency generator height (and probably the fuel storage height as well). They didn’t design for a 45 ft high wave inundating everything.
A conservative hazard review process has a generous safety factor. It does not appear that such a standard was applied here.
Well, the plants at the site are up to 40 yrs. old. I do not know what expected max earthquake was during design - perhaps 8 did provide considerable margin at the time. It also appears that the plant more or less survived the earthquake - it is the tsunami that took it to a whole new dimension.
Yup. Moreover, Richter magnitude only measures peak energy, whereas duration matters too. The Alaska quake was a prime example of the latter.
I'm a big fan of nukes, but of the smaller, more serviceable, and portable (!!!) flavor such as the Toshiba 4S proposed for Galena Alaska. That is one cool design, far easier to harden and removable if there is a problem.
It wasn’t the levees that failed in New Orleans, the failure occurred in the flood walls of the Industrial Canal. These are much weaker structures than levees.
Which shows that the safety factor was in the design to that 8.0 magnitude.
I agree that a vital nuclear industry would have long ago replaced this ancient monster. The left is forcing the industry to run its old equipment into the ground, thus assuring an eventual catastrophe.
They have their reasons, and they aren't pretty.
It survived the earthquake.
In addition the intensity at the plant was considerably less than at the epicenter 80 or so miles away.
Apparently the electrical switching equipment was in the ...
- Basement -
And that flooded...
That alone seems like a bad design choice for a nuclear power plant on the coast.
Well duh, but not a seismic wave with the consequent magnitude. I was talking about the entire array of hazards associated with a particular magnitude quake, including marine seismic waves, which is what any design hazard review for an earthquake would encompass.
And for twenty points, what is the difference between a "tidal wave" and a "tsunami"?
Answer: there isn't one. When American scientists agreed that what should have been called "seismic waves" were not "tidal waves" they decided that since the Japanese were so advanced in such matters that they adopted the Japanese term "tsunami" without consulting said experts as to what the term meant. And what do you know but the literal translation of the Japanese word "tsunami" means, "tidal wave," or at least that is what we learned in our oceanography classes. They do share very similar long wave behavior properties however.
It is true, that many reactors (and not just here) are operating well past their design lifetimes. Among other things, many materials swell and become brittle from neutron bombardment. HOPEFULLY, this is managed well!
Ever heard of Murphy?
Exactly!
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