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Power Hardware

Nebraska Nuclear Plant Flood Defenses Tested 168

Posted by Soulskill
from the good-walls-make-bad-mutant-wildlife dept.
mdsolar tips an article at the NY Times which begins: "Pictures of the Fort Calhoun nuclear power plant north of Omaha, Neb., show it encircled by the swollen waters of the Missouri River, which reached a height of nearly 1,007 feet above sea level at the plant yesterday. The plant's defenses include new steel gates and other hard barriers protecting an auxiliary building with vital reactor controls, and a water-filled berm 8 feet tall that encircles other parts of the plant. Both systems are designed to hold back floodwaters reaching 1,014 feet above sea level. Additional concrete barriers and permanent berms, more sandbags and another power line into the plant have been added. The plant was shut down in April for refueling and will remain so until the flood threat is passed. 'Today the plant is well positioned to ride out the current extreme Missouri River flooding while keeping the public safe,' Nuclear Regulatory Commission spokesman Victor Dricks said on an agency blog this week. But a year ago, those new defenses were not in place, and the plant's hard barriers could have failed against a 1,010-foot flood, the Nuclear Regulatory Commission contends in a yearlong inspection and enforcement action against the plant's operator, the Omaha Public Power District."
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Nebraska Nuclear Plant Flood Defenses Tested

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  • by Anonymous Coward on Friday June 24, 2011 @03:35PM (#36559914)

    Two weeks ago people on the Internets here (in other forums) were talking about how the plant had basically already melted down and that Obama had ordered a news blackout of the plant to conceal mass evacuations that apparently had already begun! All of this to protect his "green jobs" initiative.

    Well, guess what? I live in Omaha. There's no meltdown. No evacuation. No flooding at the site.

    OPPD's official rumor control page:

    http://www.oppd.com/AboutUs/22_007105 [oppd.com]

    OPPD flood blog:

    http://www.oppdstorminfo.blogspot.com/ [blogspot.com]

    OPPD's Twitter page:

    http://twitter.com/#!/oppdcares [twitter.com]

    • But, but, how can you trust the official page of the power companies? Don't you know that they all conspire to hide the truth about how evil electricity actually is while simultaneously using the profits they reap from us poor, victimized sheeple to purchase gallons of children's tears to wash their baby seal skinned boots in?
      • by h4rr4r (612664)

        Those are the only kind of boots that fit the reptilians, what do you want them to do?

    • by blair1q (305137)

      The aquadams are cool. And they were probably filled by using the plant's own electricity to pump the water's own water from the river's own river to negate the flood's flooding ability.

      Nuclear power FTW!

    • by Hatta (162192)

      Yep. Doesn't worry me in the least.

    • While I expect they have the flood thing handled, what gives me pause is when I looked up how many nuclear sites there are (440 roughly) and how many major disasters have occurred (chernoble, TMI and now Fukishima). So a quick calculation says if I have a plant within a few miles of me, there is roughly a 1% chance in a typical lifetime that my home will be un-inhabitable for the next 100 years or so. I'm not a big pro or anti nuke guy. Actually I was sort of positive on them until I considered the probabil

      • by Toonol (1057698)
        Do you make the same calculation for the danger of a major flood, tornado, or earthquake, which would destroy your house and have a much more likely chance of immediately killing you and your family?
      • by TheSync (5291)

        While I expect they have the flood thing handled, what gives me pause is when I looked up how many nuclear sites there are (440 roughly) and how many major disasters have occurred (chernoble, TMI and now Fukishima). So a quick calculation says if I have a plant within a few miles of me, there is roughly a 1% chance in a typical lifetime that my home will be un-inhabitable for the next 100 years or so.

        TMI did not make any private property "uninhabitable".

        Be that as it may, yes, a 1% per lifetime risk of maj

      • Re:OK for now (Score:4, Informative)

        by Solandri (704621) on Friday June 24, 2011 @08:09PM (#36563256)

        I looked up how many nuclear sites there are (440 roughly) and how many major disasters have occurred (chernoble, TMI and now Fukishima). So a quick calculation says if I have a plant within a few miles of me, there is roughly a 1% chance in a typical lifetime that my home will be un-inhabitable for the next 100 years or so. I'm not a big pro or anti nuke guy. Actually I was sort of positive on them until I considered the probabilities. I mean, some people may be NIMBY about turbines, but man, I am definitely NIMBY for a nuke plant now.

        Well yeah, that's what happens when you consolidate production. Comparing accident rate per plant (implicitly equating one nuclear plant to one coal plant), is basically the same as saying hundreds of people die when a plane crashes while only a few people die when a car crashes, therefore cars are safer. You're ignoring the fact that planes move a lot more people in fewer trips / there are a lot fewer homes around the perimeter of nuclear plants than other types of power plants for an equivalent amount of power generated. If you correctly account for the amount of power generated:

        The U.S. has just 65 nuclear plants (104 reactors) with 101 GW nominal capacity. That's an average of 1550 MW per nuclear plant. Nuclear capacity factor is about 90%, for an average 1400 MW production per plant.

        The U.S. has 1493 coal plants with a nominal capacity of 335.8 GW. That's an average of 225 MW per coal plant. Coal has a capacity factor of 60%-70%, for an average 135-158 MW production per plant. A single nuclear plant is equivalent to 9-10 coal plants.

        If you assume 1 MW wind turbines @ 20% capacity factor, that's an average 0.2 MW production per turbine. A single nuclear plant is equivalent to 7000 1 MW wind turbines.

        If you assume 15% efficient PV panels (nominal 125 W/m^2) with 18% capacity factor (typical for desert southwest), you get 22.5 W/m^2 average production, or an average 22.5 MW production per square km. A single nuclear plant is equivalent to 62 square km of solar panels.

        So if you want to compare cost, risk, and environmental impact equally, you need to compare a single nuclear plant, to 9-10 coal plants, to 7000 1 MW wind turbines, to 62 sq. km of solar panels.

        • by phayes (202222)

          great post!

        • by AmiMoJo (196126)

          Comparing accident rate per plant (implicitly equating one nuclear plant to one coal plant), is basically the same as saying hundreds of people die when a plane crashes while only a few people die when a car crashes, therefore cars are safer. You're ignoring the fact that planes move a lot more people in fewer trips / there are a lot fewer homes around the perimeter of nuclear plants than other types of power plants for an equivalent amount of power generated.

          So nuclear is safer because it when it goes wrong radioactive material is released so no-one wants to live near it?

          Nuclear power stations are run for profit, and like every other area of business that means that sometimes safety isn't the number one priority. That was the problem at Fukushima, they defences should have been better and TEPCO was told that, but failed to act. Air France didn't replace pitons quickly enough when advised to and they lost an aircraft. Railtrack didn't do proper maintenance and a train crashed. Why would a brand new nuclear plant be any different?

          Your numbers for wind and solar are way off. The Rice Solar Energy Project in California is going to produce around 150MW in 5.7km squared. It works 24/7 too BTW, so accounting for maintenance capacity will be at least 90%, probably more since the system is much simpler than nuclear. 150MW per plant might not be that impressive next to a modern reactor but on the other hand they are simple, cheap, don't need any fuel, don't create any waste and if one goes catastrophically wrong you end up with some steam and molten salt leaking out. They last longer than nuclear plants and you can re-use the site with minimal clean-up, there is no need to situate them a long way from civilisation and in the US you have more than enough space for lots of them.

    • by Mr Bubble (14652)

      "people on the Internets" have said a lot of things. Who cares? I didn't read that the plant had meted down and I have been following this closely.

      I am as assured by OPPD's public face as I am by TEPCO.

    • by AmiMoJo (196126)

      Talk about a classic straw man.

  • by Pope (17780) on Friday June 24, 2011 @03:35PM (#36559926)
    That's a bit of a bizarre measurement for river waters, no? Makes it sound at first glance that it's under 1,007 feet of water. Why not the height above the normal crest? It would make it a bit easier to visualize that's for sure.
    • by BradleyUffner (103496) on Friday June 24, 2011 @03:48PM (#36560090) Homepage

      That's a bit of a bizarre measurement for river waters, no? Makes it sound at first glance that it's under 1,007 feet of water.
      Why not the height above the normal crest? It would make it a bit easier to visualize that's for sure.

      Saying that the flood is at 1007ft of 1014ft capacity of the walls makes it sound a lot more scary that saying its at 7ft of the 14ft walls. It's nothing but anti-nuclear fud. The whole story is designed to make it hard to visualize to make it scarier.

      • Actually, the plant itself sits at 1004 ft [omaha.com] above sea level making the wall 10 ft high and they used to be less than 10 ft. So saying the water is at 3 ft up a 10 ft wall is a bit different still. But since most all of Nebraska is at 900-1000 ft above sea level, there's lots of room for the muddy Missouri to spread out rather than up. Nebraska is THE flattest state I have ever seen. Not that 10ft walls really inspire confidence in me when it comes to Nuclear power plants.

    • by jc42 (318812)

      That's a bit of a bizarre measurement for river waters, no? Makes it sound at first glance that it's under 1,007 feet of water.

      Yeah; my first thought was "WTF sort of measurement is that? Maybe I should rewrite it giving the elevation above the Moho [wikipedia.org]." Anyone know offhand how deep that is below Omaha?

      I've seen other uses of "height above sea level" for locations in the middle of a continent. I always wonder what they're trying to hide/distort/exaggerate with they do that. I tend to doubt that the writer's original sources used that base.

    • by blair1q (305137)

      Someone says the flood will reach 1010 feet. Your foundation is at 1009 feet. You know what to do.

      Someone says the river will crest 8 feet above normal. You go "what's normal? at what time on what day do they measure normal? how high is 8 feet above that where I am?"

      I like their idea better. It's a lake in the middle of town, that's all you need to visualize.

    • A sane measurement system wouldn't make it as scary sounding.
    • by riverat1 (1048260)

      They've got to measure it against some baseline. MSL is commonly used in civil engineering for all sorts of things. It's not someone trying to make it sound scary, it's just a common usage.

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      It sounds like everything worked as designed.
      A fire happened an automated fire suppression system put it out.

      • by blair1q (305137)

        and the fuel being cooled in a pool whose circulation was controlled by that switch never got hot before they restored circulation

    • The main story can be basically summarized as;

      Engineers internally and externally saw a trend of rising flood waters, and went to work on a plan to strengthen defenses. Plant management and the regulatory body had a difference of opinion, and so they lobbed paper back and forth for awhile before deciding on the current plan, which is working. Naturally, everybody has a problem with the system working and the plant remaining safe.

      *headdesk*

  • As I understand it, the issue in Japan was that, while the reactor scrammed automatically when the earthquake was detected, the rods still need time to cool down before they cool enough to no longer require power to cool.

    How long does that cooldown process take? Or do even "cool" rods still require power to remain cool?

    • by Hatta (162192)

      The Ft. Calhoun nuclear plant has been offline for some time now.

    • by blair1q (305137)

      Weeks, when the rods are somewhat depleted and due to be replaced. Months, if they're new. And after those weeks, they're still not cool enough to be moved offsite, which is why there's a cooling pool (not a static pool but one that circulates its water to cooling towers) nearby the reactor to hold them for months (after they're swapped out for fresh fuel rods) while they decay to a level of self-reactivity that doesn't generate enough heat to damage themselves if they aren't continuously cooled.

      • Weeks, when the rods are somewhat depleted and due to be replaced. Months, if they're new.

        It takes less time to cool them down when they're new than when they're old.

        Big issue for cooldown is the fission products that build up in the fuel rods from normal use. Some of them are short-lived, some long-lived, some in between.

        The long-lived stuff doesn't produce much in the way of decay heat.

        The short-lived stuff produces a lot of decay heat, but not for long.

        The medium-term stuff is what comes into play w

  • by Wansu (846) on Friday June 24, 2011 @04:35PM (#36560698)

    hmmm. I didn't see any pictures on that NY Times page.

The use of anthropomorphic terminology when dealing with computing systems is a symptom of professional immaturity. -- Edsger Dijkstra

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