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Government Power

Inspectors Warn Faulty Valves In New-Generation EPR Nuclear Reactor Pose Meltdown Risk 126

Bruce66423 writes: Valves for the new generation of French reactors being built now have raised substantial safety concerns on top of the existing issues about the quality of the steel used for the containment vessel. Similar to the Three Mile Island nuclear accident, France’s nuclear safety watchdog found “multiple” malfunctioning valves in the Flamanville EPR that could cause its meltdown. The Telegraph reports: "The watchdog reportedly cited 'multiple failure modes' that could have 'grave consequences' on the safety relief valves, which play a key role in regulating pressure in the reactor. Owned by state-controlled French utilities giant EDF, Flamanville lies close to the British Channel Islands and about 150 miles from the southern English coast. Designed to be the safest reactors in the world and among the most energy-efficient, the €9 billion (£6.5 billion) EPR has suffered huge delays in models under construction in France, Finland and China. It is now due to enter service in 2017, five years later than originally planned."
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Inspectors Warn Faulty Valves In New-Generation EPR Nuclear Reactor Pose Meltdown Risk

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  • by Anonymous Coward on Thursday June 11, 2015 @06:34AM (#49889813)

    Half-Life 3 confirmed!

  • Hack piece (Score:5, Insightful)

    by Mr D from 63 ( 3395377 ) on Thursday June 11, 2015 @06:35AM (#49889821)
    Valves don't cause meltdowns. Multiple faulty valves could inhibit the mitigation of an even that could lead to a meltdown.

    In this case, valves did not pass the required tests so they can't be used in the plant when it is built. The testing process is there for a purpose.
    • Re: (Score:3, Interesting)

      by AmiMoJo ( 196126 )

      It shows that the engineers designing and building these reactors are still unable to correctly predict and specify the needed hardware for it to be safe. All the claims about such reactors being safe and it being impossible for them to fail catastrophically are therefore questionable, because even now they can't get it right and have to rely on checks catching these faults.

      It's hardly the only screw-up either. The reactor vessel itself is compromised. It's probably fine, but the point is that the claims ab

      • No, it shows that things happen, and processes need to be in place to ensure safety.
      • by Anonymous Coward

        It shows that the engineers designing and building these reactors are still unable to correctly predict and specify the needed hardware for it to be safe.

        That or a supplier cut corners and provided faulty valves that don't perform as designed.

        IMHO if the valves fail inspection they need to be returned and sourced from a new manufacturer.

      • Re:Hack piece (Score:5, Insightful)

        by Zalbik ( 308903 ) on Thursday June 11, 2015 @11:20AM (#49892061)

        It shows that the engineers designing and building these reactors are still unable to correctly predict and specify the needed hardware for it to be safe

        How do you figure? The valves are faulty. Not designed incorrectly, but actually malfunctioning.

        This indicates possible errors in the manufacturing/supply process. It says nothing about the design.

        have to rely on checks catching these faults.

        Like every other manufacturing process EVER.

        Surprisingly, humans aren't perfect. Inspections are done specifically to ensure that mistakes are caught.

        As far as I can tell, the process is working correctly...nothing to see here.

        • This indicates possible errors in the manufacturing/supply process. It says nothing about the design.

          Actually, from where we're sitting, we don't know what it tells us. Was the design shit to begin with? Were specified tolerances inadequate? This armchair engineering stuff is fun, but if you get the right answer, it will be a coincidence.

        • by WoOS ( 28173 )

          Upps, posting to undo mismoderation.

    • They put a lot of effort into preventing a meltdown, and that's obviously a good thing, but why don't they do anything to limit the effects of a meltdown if it ever does happen? That would make all the other safety mechanisms a lot less critical. AFAIK, if a meltdown does occur in modern reactors, all the fuel just becomes a big hot lump of critical mass at the bottom of the reactor that's very hard to deal with and causes all sorts of trouble due to the enormous temperatures involved.. Why not put a wide c

      • but why don't they do anything to limit the effects of a meltdown if it ever does happen?

        They do, actually. I believe EPR has a compartment that actually safely contains a core melt, made with special materials. Containment structures are designed an built to deal with fuel melt. Three Mile Island is a great example where fuel melted but was contained with only an insignificant release of radioactivity.

        • Then what happened in Fukushima? That meltdown was't so benign, was it? Overheating, production of hydrogen, explosions, etc... When all that could have been avoided if the whole thing had been designed with materials that melt at much lower temperatures so the material is dispersed when the reactor starts to overheat.

          • Re:Hack piece (Score:4, Informative)

            by Mr D from 63 ( 3395377 ) on Thursday June 11, 2015 @10:11AM (#49891487)

            Then what happened in Fukushima?

            The plant was deluged by a tsunami, it was never designed to handle that, and that was the central flaw. Cooling systems were not available, a necessity for this plant design. However, the melted fuel is still generally contained, but there are releases of contaminated coolant which is unacceptable, an outcome of placing a plant in the path of a tsunami when it is not designed to handle it, thus disabling the features that mitigate the things you discussed.

            But, left completely with no mitigation, you are right in that the containment of older designs alone may not be enough to guarantee complete retainment under all circumstances, and newer passive designs or ones with core catching features are addressing this aspect.

            • Then what happened in Fukushima?

              The plant was deluged by a tsunami, it was never designed to handle that, and that was the central flaw. Cooling systems were not available, a necessity for this plant design. However, the melted fuel is still generally contained, but there are releases of contaminated coolant which is unacceptable, an outcome of placing a plant in the path of a tsunami when it is not designed to handle it, thus disabling the features that mitigate the things you discussed. Any mechanism which requires active mechanism to ensure stability and/or safety is obviously going to have at least one failure mode which will defeat that system. This goes for nuclear reactors which require cooling pumps, but also for automobiles with automatic transmissions that creep forward unless the brakes are applied, and of course...... airplanes. But, left completely with no mitigation, you are right in that the containment of older designs alone may not be enough to guarantee complete retainment under all circumstances, and newer passive designs or ones with core catching features are addressing this aspect.

          • Re:Hack piece (Score:4, Informative)

            by ChumpusRex2003 ( 726306 ) on Thursday June 11, 2015 @11:39AM (#49892227)
            There was a big change in design philosophy. Early reactor designs were intended to prevent meltdown and had limited mitigation. More recent designs now include substantial mitigation as well as more robust prevention strategies.

            E.g. The fukushima accident occurred because of a "common cause" failure of multiple safety critical systems - the redundant diesel generators. This failure led to a "cliff edge" cascading failure of numerous safety systems, effectively meaning that core melt was inevitable. (This is in addition to the incorrect site risk assessment, where an incorrect tsunami risk was used when assessing the suitability of the site for a nuclear power plant, and the additional failure to mitigate that risk when the tsunami risk was recognised in the 1980s).

            Most modern reactor designs (the EPR excepted) do not class their diesel generators as "safety critical", because they are not necessary to place the plant in a safe state and initiate adequate reactor cooling. In addition, nuclear regulators (Japan excepted) around the world started carefully investigating "cliff edge" scenarios following the 9/11 attacks, to see if deliberate sabotage could result in disproportionate failure of safety features. In the US, the NRC started mandating that "safety critical" diesel generators be heavily hardened against beyond design-basis natural events and other methods of attack, even if not originally conceived at design stage; that UPS batteries be upgraded to provide up to 24 hours of safety, in order to allow emergency assistance to be called in, and/or that additional electrical power sources (e.g. gas turbines) be installed in fortified near-site (to mitigate against local site damage) installations.

            A similar set of upgraded mitigations have also been in place for a while - hydrogen catalytic recombiners (these are basically catalytic converters similar to those in a car exhaust which react hydrogen and oxygen at a low temperature and low hydrogen concentration, well below the minimum ignition level. Heat generated from the recombination is used to cause natural circulation of air through the combiner to accelerate hydrogen removal and stir up the air to ensure that hydrogen cannot pool away from the recombiners) have been installed in-containment, and in buildings close to hydrogen vent pipes. In Fukushima, no hydrogen recombiners were used, instead the main containment building was inerted with nitrogen. As a result, hydrogen (and steam) built up in the containment pressurising the building. In order to reduce pressure to prevent rupture, the containment building was vented into the main reactor building, where the hydrogen mixed with air and later ignited. More modern designs vent directly outside through filters, or vent through hydrogen recombiners.

            The other complicating issue is that at Fukushima unit 1, the reactor core appears to have completely melted through the reactor vessel into the containment building, severely contaminating the water in the containment building which was being used for cooling (and also leaked through minor damage to the containment). Again, modern designs try to mitigate this. The AP1000 design fills the bottom of the reactor vessel with low-melting point, sacrificial material into which molten core material will melt, resulting in dilution, prevention of re criticality, and spreading of the decay heat. Then by flooding the containment building and submerging the reactor with water, "melt through" is prevented because of combination of external cooling water and the diluted core material, as a result the containment building itself is not contaminated. The EPR instead, has a special chamber beneath the reactor intended to spread and retain molten core material, in such a way that it would not contaminate the containment building.
            • Thank you for your exhaustive reply, that was very informative indeed. I wish they would just build lots of those reactors and get rid of the old ones, rather than extending the old ones because "nucular is dangerous so we don't want to build any more".

    • Re:Hack piece (Score:4, Informative)

      by dfenstrate ( 202098 ) <dfenstrate.gmail@com> on Thursday June 11, 2015 @08:20AM (#49890517)

      I'm more concerned about the vessel steel problems mentioned in the article. If faulty, the vessel head could be replaced (at great expense), and the reactor vessel itself can be replaced during the construction phase (at even greater expense). I would hate to see the project put at risk over the issue.

      Unfortunately, the articles are either vague or alarmist, so it's hard to be sure how serious of a problem it is. Being familiar with the nuclear industry, the 'problem' might be something like this:

      1) Carbon content for the steel has been analyzed and tested as satisfactory between 0.50% and 1.25%.
      2) Inspection reveals the carbon content at these two spots is 1.26%, outside the analyzed range.
      3) New analysis and coupon testing is necessary to determine if 1.26% is safe.

      It could even be general engineering knowledge that the steel is sufficient up to 2.00%, but since the properly documented analysis and tests haven't been done to that level, it doesn't count.

      (I am not a metallurgist and my numbers are entirely made up)

      • Well ever since the French state changed the way the plants are built and handed off construction to Areva (power plant designer) instead of EDF (electricity distributor) these little shitty details keep piling up. I'm guessing Areva gets paid for each little fix they make while EDF would actually see those fixes rebated on their final lifetime power generation profits...

        Then there is the fact that there simply isn't that many people left in working age with actual experience building nuclear power plants a

      • "Areva carried out mechanical tests in representative zones, giving impact resistance1 values of between 36 J and 64 J, with an average of 52 J, which is lower than the regulation limit (60 J) [ie. by up to 40%, as the other reply to you mentions].

        Areva also measured the carbon content of a central core sample taken from this vessel head, which revealed a higher than expected carbon content (0.30% as opposed to a target value of 0.22%)."

        From the report on the French regulator's own website: http://www.f [french-nuclear-safety.fr]

  • by tomhath ( 637240 ) on Thursday June 11, 2015 @06:40AM (#49889839)
    They're verifying everything works as it should. If the valves have a problem it's good that the problem is identified and fixed.
    • Re: (Score:2, Insightful)

      > it's good that the problem is identified and fixed.

      With the project already billions over budget and years behind schedule, events like this hardly inspire confidence that there aren't more of these gotchas in the pipeline.

      You probably wouldn't get on a plane these guys designed, but a nuclear reactor, that's just something to ignore with the wave of a hand?

      Examine your assumptions.

      • by asylumx ( 881307 )

        With the project already billions over budget and years behind schedule ... You probably wouldn't get on a plane these guys designed

        Well if they were spending that time making sure their plane wouldn't fall apart in the air, then sure I would. One of the trends of today's society is that we aren't willing to wait for things. Especially when it comes to new tech and something as risky as a nuclear reactor, I want them to take their time and get it right. Hopefully that will mean the second one they build

      • You probably wouldn't get on a plane these guys designed, but a nuclear reactor, that's just something to ignore with the wave of a hand?

        What was ignored? The processes in place to find such problems found the problem.

        This is most likely a valve manufacturing problem, not a design problem, but we don't have the details.

        • > What was ignored? The processes in place to find such problems found the problem

          We're ignoring the total unmitigated financial disaster that is the EPR. It's not that EPR had *this* problem, its that its had *all* the problems, and they just keep coming. Everyone just waves their hands and says "we fixed that!" while the money keeps piling up.

          • That is being ignored? Seems like the problems are well covered. Delays are mostly due to non-technical reasons, but the few technical items that have arisen get tremendous attention.
      • by LWATCDR ( 28044 )

        Frankly I feel the opposite.
        Any project as large and complex as a nuclear reactor, airliner, or launch vehicle that passes inspection I think one thing. They did not look hard enough.

      • Re: (Score:3, Interesting)

        by tao ( 10867 )

        I'm gonna go out on a limb and assume that you won't intend to ever flying on the Boeing 787 Dreamliner, considering that they even had several issues that made it *past* testing? I seem to recall Airbus also having some issues. Furthermore I'm guessing you won't use any Apple, Dell, Sony, or Lenovo -- those are the ones I remember, I bet there are more -- laptops either. Their exploding batteries made it past testing.

        All projects have issues. That's why you have reviews, testing, redesign, more reviews, mo

        • > All projects have issues

          Of course! But at some point the issues cost more than the project. And then you're supposed to *give up on the project*.

          Surely you've worked on a project at some point in your life that you just stop working on because it's no longer worth it?

          How many problems does EPR have to have before you reach that point? It's always WAY over budget, and at this point there is no way it could ever pay for itself. It appears highly unlikely Hinkley will use one, if anything ever gets built

    • What's the price of one of those valves? And how much is it compared to the construction of the entire plant? And compared to the amount they are already over budget? Can't they just install three times as many valves as required, rather than doing more studies that cost ten times as much? I'm not an expert, but they seem to be penny wise pound stupid. Make everything to the exact required specifications and then go over budget when things don't quite work as planned, instead of taking a huge margin and add

      • by Anonymous Coward

        It's standard practice in the nuclear industry to install key valves in 2s2p formation - i.e. 2 parallel strings of 2 series valves.

        This mitigates against single valve failure in either the stuck open or stuck closed position.

        • That may be a good idea for valves that open and close regularly. But for valves that only open in an emergency, it's probably better to just put them in parallel. 2s2p is more likely to fail closed than 2p. Anyway, I'm sure they thought of that.

  • by fnj ( 64210 )

    A reactor that costs $10.1 billion, and the fucking critical coolant valves don't fucking work when brand fucking new? WTF????? How is it possible for the design process of a doom machine to be that lackadaisical? Consider; this is after Three Mile Island and Chernobyl and Fukushima.

    Flames are licking out of my head; smoke is curling up. If you gotta mark me flamebait, I almost understand it. But you gotta ask yourself: if anybody is less than filled with rage at this shit, are they really paying attention

    • It may not be wise to get all out of sorts based on limited information from a biased or generally uninformed author.
    • ...the fucking critical coolant valves don't fucking work when brand fucking new? WTF?????

      I dunno. My dad bought a Lincoln Continental once and the power windows didn't work and the electric convertable top got stuck when he tried to put it down. Shit happens I guess.

  • 5 years late (Score:5, Informative)

    by Orgasmatron ( 8103 ) on Thursday June 11, 2015 @06:57AM (#49889919)

    What is the importance of being 5 years late?

    Costs Of Nuclear Power Plants - What Went Wrong? [pitt.edu]

  • While this is certainly a serious design issue, there is no immediate threat: the reactor where the issue was detected is being built, and is not yet loaded with fissile material.

  • Mr. Burns payed off the people so things will not get or the guy in 7G get canned as he can't even remember his name.

  • I'm pretty sure Gordon Freeman wasn't aware of that....
  • five years later than originally planned

    Better late than unsafe.

  • This is disgusting and everything possible should be done to - short of marginally increasing my electric bill or tax bill of course!
  • On a related note. (Score:1, Interesting)

    by koan ( 80826 )

    Joke F Lübbecke of the National Oceanic and Atmospheric Administration’s (NOAA) Pacific Marine Environmental Laboratory and 3 scientists from the GEOMAR Research Center for Marine Geosciences poured tracer dye into coastal waters off of Fukushima, and monitored its progress as it traveled to the West Coast of North America, to find out what might really happen.

    They have revealed their results in a new paper published by journal Environmental Research Letters.

    The paper shows that the West Coast of North American could end up with 10 times more radioactive cesium 137 than the coastal waters off of Japan itself.

    That could decimate sea life in the area, in fact one group suggest the sea life die offs seen on the West Coast could be because of Fukushima, if true how much rain water could be contaminated?
    http://www.washingtonsblog.com... [washingtonsblog.com]

    http://enenews.com/scientists-... [enenews.com]

    • That could decimate sea life in the area, in fact one group suggest the sea life die offs seen on the West Coast could be because of Fukushima, if true how much rain water could be contaminated?

      How does the seawater contaminate the rainwater? It's rather the other way around. Airborne particulates become the nexus for raindrops and fall into the ocean. Evaporation famously does not tend to carry heavy metals into the atmosphere, otherwise distillers doesn't work. It does carry VOCs into the atmosphere, which is why distillers often have a pinhole vent.

      • by koan ( 80826 )

        Well that's why it was posted as a question, I know that sea water evaporates and creates rain.

        But lets look at your point

        Evaporation famously does not tend to carry heavy metals

        Do you think ocean currents can move heavy metals from Japan to the West Cost?

        I ask because when the news points out hundreds of gallons of radioactive water leaking from the plant, they never specify whether it is a "cesium suspension" (particles of cesium in water) or if it's the water its self that is radioactive (if even possible).
        So if cesium can be suspended (or is soluble) in wa

        • Do you think ocean currents can move heavy metals from Japan to the West Cost?

          yes [csmonitor.com], absolutely [csmonitor.com]. The only question is how much. How much mixing will occur? But yes, radioactives are absolutely carried by currents.

  • So long and thanks for all the fish?

  • We'll ignore the NIMBY huge issue of what the hell we do with the long-lived wastes; this is in France. In the US, with the GOP and the libertarians wanting ever-less regulation, I say, with a 99.44% confidence, that the private sector will cut corners as far as they can go, and with a nuclear plant, the results are far more widespread and longer lasting than other power plants.

    So, who here actually lives near a nuclear plant?

                    mark

  • Nom de Dieu! I thought that the French had their nuclear reactors down to a fine art. Zut alors!

    Well, back to ze old drawing board, ne?

    • The old ones they licensed from Westinghouse seem to work fine. It's this new POS (ahem) MARVELOUS 3rd generation reactor design they made with the Germans that ain't work. Not that I find it surprising.

  • Seriously, France knows how to produce reactors correctly. The only way for them to be screwing this up, is if they outsourced this. And if they sent this to China, well, China has reasons for wanting weak reactors in the west.
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