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Browns Ferry Nuclear Power Plant  (Source: svsnowgoose.com)
A valve on its residual heat removal system was stuck shut, which prompted in-depth inspections by the NRC

Nuclear power has received a lot of criticism lately due to the 9.0-magnitude earthquake that rocked Japan on March 11. U.S. Senators urged the Nuclear Regulatory Commission (NRC) to repeat the inspection of nuclear power in the United States after it was already deemed safe, and French President Nicolas Sarkozy called for a global nuclear review after visiting Japan.

Despite all of these negative reviews, there are also many advocates who see the benefits of cheap, clean and reliable nuclear power as an alternative energy source. U.S. President Barack Obama even embraced nuclear energy in last year's State of the Union address

No matter which side you're on, many can agree that safety comes first, and now, federal regulators are concerned about the safety of an Alabama nuclear plant after its emergency cooling system failed. 

The Browns Ferry nuclear power plant is located near Athens, Alabama and is run by the Tennessee Valley Authority. A valve on its residual heat removal system was stuck shut, which prompted in-depth inspections by the NRC.  

According to reports, there have been previous problems with the valve. Originally, the valve failed sometime after March 2009, but wasn't identified until October 2010 when the plant was being refueled. The valve was fixed at that time, and was labeled as a manufacturer's defect. Despite the plant's effort to fix the valve and inspect all others like it, the NRC criticized the plant for not finding the valve issue sooner through routine inspections.

"The valve was repaired prior to returning the unit to service and Browns Ferry continued to operate safely," said Victor McCree, the NRC's Region ll administrator. "However, significant problems involving key safety systems warrant more extensive NRC inspection and oversight." 

Had there been an emergency, the NRC worries that the faulty valve could have prevented the emergency cooling systems from working correctly. For this reason, the NRC will continue to review the safety culture, organization and performance of the plant. 

"The results of this inspection will aid the NRC in deciding whether additional regulatory actions are necessary to assure public health and safety," said McCree.  

For the time being, the NRC has issued a red finding against the Brown Ferry nuclear plant, which is the most severe ranking given to a plant for inspection. Only five red findings have been issued in the U.S. in the past decade. It is unknown whether the Tennessee Valley Authority will appeal the finding from the NRC at this time.



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RE: oh please...
By kattanna on 5/12/2011 2:47:30 PM , Rating: 3
all the article says, aka actual facts, is that the last hard inspection of note was march 2009. when they did another inspection during routine refueling in october of 2010 they noticed the valve was not working and replaced it.

that does NOT mean the valve was broken for over a year. for all we know it broke in september of 2010. dont read more into something that what is.

also..from the actual article

quote:
In an emergency, the failure of the valve could have meant that one of the plant's emergency cooling systems would not have worked as designed.


note the plural there. there are always multiple safety systems, so in the exact case of one system failing, it will not be an issue.

also note that all this happened in OCTOBER 2010.. yet only now.. after japan.. is the NRC getting all "bad plant" on them


RE: oh please...
By ClownPuncher on 5/12/2011 3:13:28 PM , Rating: 2
That is how news is reported, there are obvious implications, but it is left just ambiguous enough that they don't have to correct themselves when they learn the actual facts. Makes for more page hits!


RE: oh please...
By DanNeely on 5/12/2011 3:18:38 PM , Rating: 2
8 months is fast for the govt to move; even assuming the TVA reported the problem immediately.


RE: oh please...
By eggman on 5/12/11, Rating: 0
RE: oh please...
By SunTzu on 5/12/2011 5:43:12 PM , Rating: 2
Once again, this kind of inspection isnt done while the plant of is operational, for technical reasons. This *is* the routine inspection.


RE: oh please...
By rcc on 5/12/11, Rating: 0
RE: oh please...
By B-Unit on 5/12/2011 4:09:17 PM , Rating: 2
Your right, we dont know when it actually broke. BUT we do know that noone bothered to check on it between March 09 and October 2010. Plenty of cause for concern, wouldn't you say?


RE: oh please...
By ebakke on 5/12/2011 5:57:30 PM , Rating: 2
quote:
Plenty of cause for concern, wouldn't you say?

I wouldn't say ... yet. Without knowing the maintenance schedule of that valve it seems foolish to claim any length of time is acceptable or not.


RE: oh please...
By Solandri on 5/12/2011 9:02:34 PM , Rating: 2
quote:
BUT we do know that noone bothered to check on it between March 09 and October 2010. Plenty of cause for concern, wouldn't you say?

Reactors normally run about 18 months between refueling. Mar '09 to Oct '10 is 19 months. So this sounds like the regular interval between scheduled refuelings and maintenance checks.

It's difficult to say without knowing exactly where the valve was, but it's impractical or exceedingly dangerous to test certain sections of the cooling system (emergency or otherwise) while the reactor is in operation. You're better off building in multiple redundant systems, so it's highly unlikely that any one will fail. Then test them all during refueling. (Chernobyl happened because they conducted a live test of a new cooling system on an active reactor.)


RE: oh please...
By Solandri on 5/12/2011 9:04:08 PM , Rating: 2
quote:
so it's highly unlikely that any one will fail

Obviously that should be "highly unlikely that all will fail". Serves me right for visiting the bathroom before hitting post. =p


RE: oh please...
By NucNut on 5/13/2011 5:42:58 AM , Rating: 2
The valve in question is only flow testable during shutdown conditions. Thus, if the plant runs for two years, there will be two years between opportunities to verify that the valve actually passes flow.
The system in question is a multipurpose system which is used during plant shutdowns to provide decay heat removal and also during postulated accidents to provide core cooling.
Not a good thing that it was not identified earlier, but also not a demonstration of gross malfeasance. It is pretty difficult to prove a valve disk has not separated from the stem without establishing flow, and it is not part of the design of many nuclear plant emergency cooling systems to be able to perform full flow testing when the plant is in operation. In this instance, the system is a low pressure system and thus could not overcome reactor pressure to inject water and prove flow path continuity.


RE: oh please...
By Xcpus on 5/14/2011 4:04:59 PM , Rating: 2
And for all we know it may have broken back in March. Point being we didn't know it was broken as there aren't enough inspections of the sort.

People like you are over zealous Nuclear Energy supporters. You are just as bad as the anti-Nuclear Energy folks IMHO.

Nuclear Energy ought to be left to "Liberals" to manage... not cost cutting "Conservatives". What I mean is that either a Nationalized model (no Public Ownership of Nuclear Energy) or a heavily regulated Private Nuclear industry ought to be permitted imho.

And I'm an anarchist lol.


RE: oh please...
By Xcpus on 5/14/2011 4:06:08 PM , Rating: 1
"Public Ownership" not "No Public Ownership"


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