Tuesday, April 14, 2009

Fires at Nuclear Plant

Article

Are they falling apart? Sinking under the weight of their own stupidity? Who knows? These fires seem to be a bit much, though, especially since they are trying to wave their magic wand and restart the units. What was really damaged? How did they fix it? I think this is a fine example of closed-mouthed bloody-minded opacity gone amuck.

6 comments:

harbles said...

Bad news. Either they have a fire bug or the wiring is arcing all over the place. Maybe they store oily rags in cardboard boxes? I wonder if they publish accident reports on those fires?

Mona Albano said...

Probably their procedures require them to file accident reports. Publishing them might be another matter. Maybe you can get onto a Concerned Citizens' Committee to review safety.

Mona Albano said...

Oh, now that I go to the article I see that it's in Japan.

But maybe there's still a concerned citizens' group here. There were 10,000 pages of procedures at our nuclear plants (and probably more now). I happen to know because they are an example of content management done by The Rockley Group, who demonstrated how to put them online for quick retrieval.

Harbles said...

Found some stuff about a fire started during the quake.

2. FINDINGS
2.1 - FINDING DESCRIPTION-BACKGROUND
Background:
- One of the first announcements to the public after the earthquake of 16 July 2007 that
affected the Kashiwazaki-Kariwa nuclear power plant concerned the fire in the in-house
electrical transformer of Unit 3. The fire was initiated by sparks from a short circuit caused
by large ground displacements (settlements) of the transformer foundation (see Appendix V
of Volume II of this mission report). The spark caused the ignition of oil leaked from the
transformer. The fire was extinguished by the local municipality fire brigade approximately
2 hours after it began.
- Although the transformer was separated by a firewall, active actions for extinguishing the
fire were not possible because the outdoor fire protection system of Units 1-4 was damaged.
Safety Significance:
- The particular fact of the fire in the in-house transformer has no safety significance for the
plant. The in-house transformer is not an item of safety related equipment and does not
affect the nuclear safety of the unit. Nevertheless, the fact is significant from the broad point
of view of safety due to seismically induced events.
- Frequently fire protection systems are not seismically qualified and may suffer seismic
damage. However, the IAEA Safety Guide NS-G-1.6 recommends that seismically induced
events, such as fires, be carefully considered in the plant safety analyses and adequate
counter measures be taken.
- The damage of the outside water fire protection system of Units 1 to 4 is a cause of serious
concern.
- The multiple failure of the fire protection system was caused mainly due to large ground
deformations produced by the earthquake. The fire protection piping was not seismically
qualified because this is not required by current codes. It was indicated by TEPCO that the
code requires only the installation of fire protection walls and that has been provided.
An upgrade of the fire extinguishing system is planned with increased capacity. The source of
water is the filtrated water tank that is shared by Units 1 to 4. The indoor and outdoor fire
systems have a total capacity of 350m3/h and they are driven by motor and diesel pumps,
respectively. Although the present capacity might be sufficient, the effects of the earthquake
showed that the outdoor system has been affected by a common cause failure.
- The underground piping is very vulnerable to large soil deformations such as those that
occurred at the Kashiwazaki-Kariwa nuclear power plant and this should have been
considered as a weak link in the analyses of the fire extinguishing system. Associated
counter measures should have been properly taken.
3 – LESSONS LEARNED:
1. Seismically induced fires are frequent events after an earthquake in urbanized areas but are
relatively rare at a nuclear power plant. Although not directly related to nuclear safety, the
fire in the in-house electrical transformer started as result of the 16 July 2007 earthquake
demonstrated problems in the fire fighting capability of the plant. The analyses made by the
plant personnel and the regulatory authority show that there is a clear understanding of the
root cause of the fire, of the deficiencies in the fire management system and of the ways for
improving them.
2. In any case, common cause failure should be avoided. Failure of the fire fighting system
(tanks, pumps, piping, distribution system) and its consequences can be minimized by
providing adequate seismic capacity, redundancy and diversification of the systems.
3. Large soil settlements often cause piping failure, as was the case at the Kashiwazaki-Kariwa
nuclear power plant when subjected to the 16 July 2007 earthquake. Flexible joints, flexible
penetrations, protective buried channels and other means could be used in order to minimise
probability of failure.
From here .

Harbles said...

And there is this from TEPCO but no mention of "a string of fires" since.

Harold Asmis said...

Silliness with earthquakes and fire protection is not confined to those guys.