Japan Earthquake

Japan Earthquake | Page 2928

I don't know what an overpower condition is but it seems some iffy mods were made
This investigation was prompted by an overpower condition on
Byron Unit 1 and 2 and Braidwood Unit 2 resulting from an Advanced Measurements and
Analysis Group (AMAG) modification implementation. Specific objectives of the investigation
were to:
1. Evaluate whether the initial implementation and analysis of the AMAG installation was
conducted appropriately and with sufficient rigor.
2. Evaluate if decisions made were based on a full understanding of short and long term
risks including the potential of a unit overpower condition.
3. Evaluate whether the roles and responsibilities for making and implementing decisions
were established and understood by corporate, the sites, and vendors involved.
4. Evaluate the process utilized for challenging decisions made, and the results of those
decisions, throughout the AMAG implementation process. Specifically, did the sites feel
pressure to continue to operate at the higher power levels?
5. Identify insights and lessons learned to improve Exelon Nuclear's technical issue
pbadupws.nrc.gov
by elainekirk 1/31/2012 2:43:56 AM

@dean rest well dean
by elainekirk 1/31/2012 2:44:51 AM

From Elaine's earlier NRC on Byron:
On August 4, 1998, Line 0621 tripped and a loss of off-site power subsequently occurred. The loss of off-site power was due to a 94X relay that failed to reset after the fault. The false trip signal from the failed relay in conjunction with other plant conditions caused a loss of off-site power to the Unit 1 System Auxiliary Transformers when the operator attempted reclosure of OCB 5-6.
by lillymunster 1/31/2012 2:48:06 AM

last september they reported a green risk from an event when it was actually a yellow which makes it feasable that this is maybe wrongly assessed www.nrc.gov
by elainekirk 1/31/2012 2:52:03 AM

@elainekirk they appear to have 3 incoming power sources and I think each unit has access to all 3 incoming lines via a cross - tie. The diagram is rather convoluted compared to others as far as actual cross connections
by lillymunster 1/31/2012 2:56:49 AM

oooops-a-daisy maybe we should keep a copy it may disapear pbadupws.nrc.gov
by elainekirk 1/31/2012 2:57:01 AM

@lillymunster what do you make of the oops-a-daisy do you think they replied?
by elainekirk 1/31/2012 2:57:48 AM

if it is a transformer fire would that affect all 3?
by elainekirk 1/31/2012 3:05:33 AM

@elainekirk I think they tried to do the bare minimum and the NRC said no. Watching the various back and forth between power companies and the NRC it is like a bratty child trying to extend their bed time. :-)

The transformer losing access to all 3 incoming lines seems odd. If you look at some of the other issues at Byron with the electrical is seems like problems cascade where one problem makes another problem. But one would assume there would be protections in place to isolate problems.
by lillymunster 1/31/2012 3:10:23 AM

Looking at that diagram my guess is more than one thing had to fail to lose all power into unit 2.
by lillymunster 1/31/2012 3:15:51 AM

maybe if these capacities were not increased do not have long to sort the problem out from what I can tell if they lose the deisel its curtains pbadupws.nrc.gov
by elainekirk 1/31/2012 3:16:42 AM

#2 could possibly have 3rd cycle fuel in it , if so would it be more vulnerable? pbadupws.nrc.gov
by elainekirk 1/31/2012 3:21:49 AM

@elainekirk not familiar with AXIOM cladding. They seem to make a big deal about it like it is newer or requires more vigilance when running it?
by lillymunster 1/31/2012 3:25:41 AM

www.nrc.gov
we have pics
by elainekirk via Nrc.gov 1/31/2012 3:26:23 AM

bottom two rows of pics are byron if any use www.nrc.gov
by elainekirk 1/31/2012 3:27:44 AM

Axiom cladding is a newer cladding by westinghouse that allows higher burnup?
by lillymunster 1/31/2012 3:28:15 AM

that'll be why they increased power output and got told off then
by elainekirk 1/31/2012 3:30:12 AM

those byron pictures have a few images of the switchyard including equipment with labels on them. They could come in handy.
by lillymunster 1/31/2012 3:31:16 AM

#2 offsite power resources here must get to bed g'night all www.nrc.gov
by elainekirk 1/31/2012 3:34:04 AM

@elainekirk nite!
by lillymunster 1/31/2012 3:42:10 AM

UN nuclear agency approves Japan's stress tests www.reuters.com Really????? U.N. nuclear experts on Tuesday gave their backing to stress tests aimed at showing Japan's nuclear plants can withstand the sort of disasters that devastated the Fukushima plant last year, potentially bolstering a government campaign to restart idled reactors and avoid a summer power crunch.
by Mid Valley 1/31/2012 4:51:03 AM

US nuclear reactor loses power, venting steam www.timeslive.co.za
by Mid Valley 1/31/2012 4:57:30 AM

Preliminary Earthquake Report 2.4 magnitude in Pikeville, Wisconsin. Depth: 9.90 km (6.15 miles) hisz.rsoe.hu
by MaryW 1/31/2012 4:57:43 AM

Japan Cabinet OKs bills putting 40-year cap on reactor lives, aiming to boost nuclear safety www.washingtonpost.com
by Mid Valley 1/31/2012 5:00:31 AM

Radiation Fears Slow Tsunami Cleanup: www.news24.com
by Mid Valley 1/31/2012 5:04:29 AM

Just restarted.
by Pedro Jesus 1/31/2012 9:08:29 AM

"U.N. experts OK Japan's nuclear 'stress tests'" (Kyung Lah) edition.cnn.com
by Pedro Jesus 1/31/2012 9:42:21 AM

Morning-afternoon-evening. Not finding anything now on Byron NPP in the news yet
by lillymunster 1/31/2012 12:39:15 PM

I did find something tucked into an AP morning report. Nothing new. They still don't know the exact cause and power still not restored. www.newsday.com
by lillymunster 1/31/2012 12:42:21 PM

In 1984 Byron was denied a license to operate after the plant was built citing so much non-compliance and quality assurance failures. The denial was without opportunity to review or make changes. I don't know who got bribed or what changed for the NRC to change their stance. It was the only time in NRC's history up to that point where an operating license was flatly denied. news.google.com
by lillymunster 1/31/2012 12:47:15 PM

@lillymunster Hi, good afternoon. I'm logging out as moderator now that you're here. Where is that Byron NPP located? I wasn't following.
by Pedro Jesus 1/31/2012 1:04:46 PM

@Pedro Jesus it is about 96 miles west of Chicago.
by lillymunster 1/31/2012 1:07:30 PM

Byron has a long history of problems including issues with the entire switchyard failing and taking out offsite power to a unit.
by lillymunster 1/31/2012 1:08:02 PM

Byron has NRC known issues with the steam generator. This is what Joieau claimed was allowing the radiation leaks over to the non nuclear side steam releases.

Section IV.1.A.vi.2.d, "Steam Generator Steam Drum Evaluation," states that increased fluid velocity at MUR power uprate conditions may increase current estimated degradation rates up to 25 percent for Byron, Unit No.2, and Braidwood, Unit 2. Additionally, it states that erosion-corrosion has previously been detected in several components of the Byron, Unit No.2, and Braidwood, Unit No.2, Model D5 SGs steam drum internals. Please provide examples of the most rapid degradation rates observed to date for steam drum internals and discuss whether a 25 percent increase in degradation rate would impact the inspection frequency and/or scope of these components. pbadupws.nrc.gov
by lillymunster 1/31/2012 1:13:04 PM

@all - reminder - live blogging of the NRC public meeting on spent fuel storage today at 1pm CST
by lillymunster 1/31/2012 1:13:49 PM

@lillymunster Oh dear... another one of those.
by Pedro Jesus 1/31/2012 1:14:47 PM

@Pedro Jesus NRC meeting or another plant that is falling apart? :-D
by lillymunster 1/31/2012 1:16:22 PM

@lillymunster I meant the falling apart plant...
by Pedro Jesus 1/31/2012 1:16:58 PM

greetings to all
by dean 1/31/2012 1:20:28 PM

www.acmela.org good report on tritium with lots of history
by dean 1/31/2012 1:20:42 PM

Greetings dean.
by Pedro Jesus 1/31/2012 1:20:54 PM

@Pedro nice to see you
by dean 1/31/2012 1:21:12 PM

It would be nice if they would say exactly how much tritium is leaking rather than the "its safe" comments.
by lillymunster 1/31/2012 1:27:02 PM

www.nuc.berkeley.edu a BWR, like Fukushima, atmospheric dump is only done as an emergency procedure. Look at the following diagram of a BWR courtesy of the NRC:

www.nrc.gov

Imagine there is a valve in that steam line at the top. Imagine that this valve can divert steam from the turbine at right to the outside. In a BWR, there is only one loop of water, and it goes through BOTH the reactor and the turbine. Since it goes through the reactor, the water is slightly radioactive, and blowing it into the environment releases radiation.
by dean 1/31/2012 1:31:03 PM