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Comments

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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:Stylized (109 comments)

Thanks for the correction. I mis-read the statements and I was wrong on that one. I got thrown off by the sudden switch from a discussion of external events to this topic which really isn't external events. I admit when I am incorrect and appreciate your clarification.

Still, be careful with the terminology of 'accident' and 'near miss' and the statistics behind them, as they get applied and represented in a very inconsistent manner by the anti-nuke lobby.

3 hours ago
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:How would that be even helpful? (109 comments)

typical response for those that can't make a valid point.

3 hours ago
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

Agreed. Japan is a high seismic activity area and should have set higher requirements to start with, just as they should have never assumed a massive tsunami would not happen when its clear that it could based on the geology of the area and the type of coastline. Raising the minimum requires going back and re-analyzing to see if the design is still adequate and making modifications where it isn't, costly to do after the fact.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

I think you did not read it, because it does not say "the plant survived an earthquake undamaged". So, you are resorting to changing my words so you can play a game of "gotcha", and you have gone down that path because your arguments were failing.

Please just stop now while you are behind.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

yes, please find that quote.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

The plant was not designed to operate when inundated by water, it was not designed to withstand a tsunami of this magnitude, it was assumed a tsunami would never breach the protective wall and reach the plant, therefore, simple things like protecting the structures from the forces of the tsunami, and waterproofing all of the ducts, vents, doors, etc with controls over when and how long they can be open, were never in place.

Even with diesel failures at a unit, it could still have been safely shut down had the tsunami not hit. One option could have been borrowing power from another unit, but that would not necessarily be required. Diesels are very reliable machines that are tested on a regular basis. Adding a third does not improve the situation as much as you may think, because if two fail at the same time, its more likely a common cause than a different one, and the third diesel would stand a good chance of suffering that common cause as well. That is where testing, maintenance and reliability programs become very important. Also, having diverse means to achieve a safe state is also key.

The key is not placing a plant that cannot withstand a tsunami where it can be hit by one, because designing to withstand a tsunami suddenly inundating the site it really not practical.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

First, there were more than one unit that all met essentially the same fate from the tsunami, it was not just one unit, and each unit has multiple safety systems that are designed to complete their mission even if one fails, as the assumption is always that something will go wrong. There were plenty of operable cooling components in place to shut down the plant after the earthquake. Not so after the tsunami.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

You claimed the plant was not at all affected by the earthquake, which is wrong.

I never said the plant was not at all affected, that is another fabrication by you. The safety systems, those designed to operate after such an event, were quite capable of safety shutting down the plant after the quake. They were not capable after the tsunami hit.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

Outside power is not required to shut the plant down. There nearby plants, the ones right next door, the ones not hit by the tsunami, also lost power but shut down just fine. The Fukushima Daiichi plants were in the process of shutting down after the quake and before the tsunami, even though offsite power was lost. The emergency diesel generators had started and the units were just fine to shut down. Had the tsunami not hit, regardless of the quake, you would never have heard of Fukushima Daiichi, just like you probably can't name any of the units that survived the severe earthquake without googling.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

^you can make stuff up all you want, but there are no such thing as safety related electrical pillars. Offsite power supply is not credited in a safety analysis of the plant, and failure of those systems is just fine, as the safety related systems could more than handle the earthquake. The plant was doomed when it was inundated by water and the safety related systems became inoperable.

You should learn more about how a plant safety design basis is developed, and in particular the difference between safety related and non-safety related systems and components.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

Shouldn't we be designing reactors to handle any quake that is reasonably likely to occur? Japan is highly prone to earthquakes - I'd expect any reactor design to account for a very strong one.

They do, but you have to prescribe a specific requirement in the license and that is on the regulator. The actual designs handle quite a bit more than the licensed design specification, because a reactor designer will typically consider the worst site where a reactor is expected to be built, and the site specific design can be augmented if necessary. US plants have conservative earthquake requirements to start with as prescribed by the NRC, and they do consider the location. Designing a facility to withstand an earthquake is really not that big of a technical challenge.

Withstanding a tsunami is a whole different ball game... there is no margin for something like that, you either place the plant where it won't get hit, or you design it to operate underwater with destroyed surroundings... that latter is not practical.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

Plants do address what they call "beyond design basis" events with various coping scenarios over and above the prescribed design basis accidents and events. Post Fuku response is really an extension of that severe accident management element. But that is not in response to a specified event, rather the approach is to simply imagine the plant is left crippled badly in various ways and put mitigations in place to cope. Now, they simply imagine a more crippled starting point. That's all well and good and conservative, but it doesn't address an event, which was the failing at Fukushima.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

Can you please describe the event that suddenly places Turkey Point underwater without sufficient warning to take appropriate actions? Many hurricanes have come through, even those with the highest scale, and TP has been quite fine. If you can show there can be a surge will inundate the plant that is not accounted for, please specify the height and relative limits for the plant.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

It will, in fact the reactors near Fukushima experienced major quakes beyond their design basis, remained intact and actually saw little or no structural damage. Only those plants that got flooded by the tsunami had problems, because they were not designed to be underwater.

If a major natural disaster hits, a nuclear plant is probably one of the safest places to be.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:Stylized (109 comments)

Add that 'near miss' is not an official event defined event by the NRC , but rather that of the anti nuke group, so they decide what to call a near miss.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:How would that be even helpful? (109 comments)

Well, If we are talking about shuttered plants that are not operating, with no fuel, then they have plenty of margin, believe me. Anyone reading this thread to this point will clearly see how ridiculous your contention is, so I don't need to continue, but for your own edification, if HB were operating and were hit with a large quake, it would still likely withstand it due to the margin.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

"must do more" and "do not reflect" are two completely different things with different meanings. Its pretty simple, really.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:Stylized (109 comments)

khallow, he just doesn't understand about application of statistical data, and repeats what he reads from nuclear FUD websites. You won't get a logical response to this obvious point.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:already done (109 comments)

Very good points tp1024. It again reflects our societies complete skewing of risk when it comes to nuclear energy, and radiation in general.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

Mr D from 63 Re:How would that be even helpful? (109 comments)

Well, there you go, plants that are not designed to withstand an earthquake that is considered to be possible in an area are not allowed to operate. HB could not prove its safety case based on this EXTERNAL EVENT, and was shut down, many years ago.

yesterday

Submissions

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Nereus Deep Sea Vehicle Lost

Mr D from 63 Mr D from 63 writes  |  about 3 months ago

Mr D from 63 (3395377) writes "On Saturday, May 10, 2014, at 2 p.m. local time (10 p.m. Friday EDT), the hybrid remotely operated vehicle Nereus was confirmed lost at 9,990 meters (6.2 miles) depth in the Kermadec Trench northeast of New Zealand. The unmanned vehicle was working as part of a mission to explore the ocean’s hadal region from 6,000 to nearly 11,000 meters deep. Scientists say a portion of it likely imploded under pressure as great as 16,000 pounds per square inch."
Link to Original Source
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SEC Releases Long-Awaited Rules on Crowdfunding

Mr D from 63 Mr D from 63 writes  |  about 9 months ago

Mr D from 63 (3395377) writes "The Securities and Exchange Commission announced rules that will make it legal for entrepreneurs and startups to raise money by selling pieces of their company to everyday, mom-and-pop investors.

The proposed rules were released this morning and the Commission voted to adopt them. The rules will now be available for public comment for 90 days before a final set is drafted and adopted.

Proposed rules include;
1. Entrepreneurs could raise $1 million per year.
2. The amount individuals could invest would be capped depending on their net worth.
3. Equity in a company must be held for one year
4. Transactions must be supervised by an SEC-registered intermediary
5. Only U.S.-based companies would be eligible to crowdfund
6. Financial disclosure requirements. Companies that participate in online equity crowdfunding would need to disclose who are their primary officers and directors and anyone who owns more than 20 percent of the company."

Link to Original Source

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