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Century-old stone “tsunami stones” dot Japan's coastline (2015)

smithsonianmag.com

21–30 of 66 posts

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#21

Fun facts, Fukushima Daiichi Nuclear Power Plant was built beyond the warning limit of the tsunami stones. If those people that setup the tsunami stones are still alive during the incident they will have a kahuna of "I told you" moment.

"Beyond" is completely ambiguous in this case. Do you mean above or below?

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#22
post #21

Fun facts, Fukushima Daiichi Nuclear Power Plant was built beyond the warning limit of the tsunami stones. If those people that setup the tsunami stones are still alive during the incident they will have a kahuna of "I told you" moment.

"Beyond" is completely ambiguous in this case. Do you mean above or below?

Well obviously they mean below

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#23

Earlier quoted context omitted.

Do you have a citation for this? The most Gemini could say is: "While research has not identified a specific tsunami stone located at the Fukushima Daiichi site that was directly violated, the spirit of these ancient warnings was undeniably ignored." ( https://aistudio.google.com/app/prompts?state=%7B%22ids%22:%... )

I don't know if there are "Tsunami stones" in the area but the nuclear power plant is built at sea level [1] so would most probably be below them. The issue is the height of the seawalls that was not sufficient (and perhaps historical warnings, if any, were ignored): " The subsequent destructive tsunami with waves of up to 14 metres (46 ft) that over-topped the station, which had seawalls " [1] Edit: Regarding histor…

IIRC the issue was the emergency diesel generators being flooded, preventing them from powering the emergency cooling pumps, resulting in the meltdowns from residual heat in the reactor cores and spent fuel pools.

Various construction changes could have prevented this from happening:

- the whole power plan being built higher up or further inland

-> this would likely be quite a bit more expensive due to land availability & cooling water management when not on sea level & next to the sea

- the emergency generators being built higher up or protected from a tsunami by other means (watertight bunker ?)

-> of course this requires the plan cooling systems & the necessary wiring itself working after surviving a massive earthquake & being flooded

An inland power plant - while quite wasteful in an island country - would be protected from tsunamis & certainly doable. On the other hand, I do wonder how would high concrete cooling towers handle strong earthquakes ? A lot of small cooling towers might have ti be used, like in Palo Verde nuclear generating station in Arizona.

Otherwise a bizzare case could still happen, with a meltdown possibly happening due to your cooling towers falling over & their cooling capacity being lost.

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#24

Fun facts, Fukushima Daiichi Nuclear Power Plant was built beyond the warning limit of the tsunami stones. If those people that setup the tsunami stones are still alive during the incident they will have a kahuna of "I told you" moment.

>Onagawa was… 60 kilometers closer than Fukushima Daiichi [to the epicenter] and the difference in seismic intensity at the two plants was negligible. Furthermore, the tsunami was bigger at Onagawa, reaching a height of 14.3 meters, compared with 13.1 meters at Fukushima Daiichi. The difference in outcomes at the two plants reveals the root cause of Fukushima Daiichi’s failures: the utility’s corporate “safety culture.”

>Before beginning construction, Tohoku Electric conducted surveys and simulations aimed at predicting tsunami levels. The initial predictions showed that tsunamis in the region historically had an average height of about 3 meters. Based on that, the company constructed its plant at 14.7 meters above sea level, almost five times that height.

>Tepco, on the other hand, to make it easier to transport equipment and to save construction costs, in 1967 removed 25 meters from the 35-meter natural seawall of the Daiichi plant site and built the reactor buildings at a much lower elevation of 10 meters.

https://thebulletin.org/2014/03/onagawa-the-japanese-nuclear...

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#25
Previous and related:

Century-old stone "tsunami stones" dot Japan's coastline (2015) - https://news.ycombinator.com/item?id=39892533 - April 2024 (142 comments)

Tsunami Warnings, Written in Stone (2011) - https://news.ycombinator.com/item?id=10122825 - Aug 2015 (10 comments)

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#26
post #23

Earlier quoted context omitted.

I don't know if there are "Tsunami stones" in the area but the nuclear power plant is built at sea level [1] so would most probably be below them. The issue is the height of the seawalls that was not sufficient (and perhaps historical warnings, if any, were ignored): " The subsequent destructive tsunami with waves of up to 14 metres (46 ft) that over-topped the station, which had seawalls " [1] Edit: Regarding histor…

IIRC the issue was the emergency diesel generators being flooded, preventing them from powering the emergency cooling pumps, resulting in the meltdowns from residual heat in the reactor cores and spent fuel pools. Various construction changes could have prevented this from happening: - the whole power plan being built higher up or further inland -> this would likely be quite a bit more expensive due to land availabil…

Another option is designing fail safe reactors. CANDU reactors designs are over 60 years old now and were built fail safe so that if outside power to the core is cut off the system would safe itself by dropping control rods which are held up by electromagnets into the core.

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#27

I've always been fascinated by these because I love long term thinking. What current "tsunami stone" would you leave to future generations to prevent catastrophe?

With radiation half lives what they are, our society should be brainstorming how to segregate and mark nuclear waste storage areas. All areas that store radioactive waste.

Without clear warnings and boundaries humanity is just waiting for a catastrophe.

A tiny sign and words don’t count.

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#28
post #20
post #17

Earlier quoted context omitted.

They just do the same thing with regular homes :)

Sadly, that's at least partially true. But rebuilding on a sight where a home was destroyed eliminates the information value (that this site isn't safe from tsunami) and the coverage is far from uniform/regular (so you can't tell if there are no buildings in an area because it was previously undeveloped or is unsafe).

‘How old are these buildings?’ would be wise to consider.

This probably works for a variety of things and in many places.

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#29

I've always been fascinated by these because I love long term thinking. What current "tsunami stone" would you leave to future generations to prevent catastrophe?

https://www.reddit.com/r/georgism/comments/102jg2f/everybody...

What’s the counter argument to that sign?

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#30
post #21

Earlier quoted context omitted.

"Beyond" is completely ambiguous in this case. Do you mean above or below?

Well obviously they mean below

I got very confused too. After reading a few times I interpreted it as a typo.
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