Tuesday, March 29, 2011

Lessons Learned from Japan

Constellation Energy Nuclear Group's Chief Nuclear Officer Maria Korsnick discusses lessons learned for the industry following the recent events in Japan. Visit ‪http://bit.ly/gT2XY5‬ to learn more about industry actions.

Visit the NEI Network for a lot more videos.

7 comments:

Scott said...

Why are we not hearing anything about hydrogen build-up issues during an emergency situation? The explosions that occurred at Daiichi did serious damage to the facilities, put the reactors at further risk, and are now greatly hampering efforts to contain the situation due to debris and significant damage to structural, electrical, and other systems. I've read that hydrogen build-up was also a big concern during the Three Mile Island incident. Has this concern already been mitigated at US nuclear plants? And if so, why is that not being communicated to the public?

David Bradish said...

Scott, CNN did a video a few days ago on Alabama's Browns Ferry nuclear plant which is similar in design to the Fukushima units. At the beginning of the video, there is a white large hardened pipe that everyone is staring at which is one of the modifications the industry made after TMI to vent primary containment at high pressure. This should prevent the secondary containment from exploding. It is not believed that the Fukushima units had hardened vents like this but we'll eventually find out. Right now the nuclear industry is going back to make sure the hardened vents in the US do what they're supposed to and that the plants take away any data from Japan.

This design modification, which was done a few decades back, has been communicated at our website and in other places, sometimes folks miss it.

Alan said...

Where can I find the INPO IER 11-1 document?

Thanks.

David Bradish said...

INPO documents are usually only for executive industry folks such as CNOs. Unfortunately you won't be able to find IER 11-1 anywhere online.

Brian said...

Alan, you can't find the INPO document online, but you can find a (probably the latest?) WANO SOER 2011-2, which incorporates INPO's findings. Here, for now: http://www.snus.sk/2011/fukushima/SOER_2011_2_en1_Fukushima.doc

George Martin said...

I read the WANO SOER 2011-2, which incorporates INPO's findings.

It is nothing but fluff. All it does is instruct plants to review their procedures and check readiness of equipment.

Something they should be doing on a regular, routine basis.

Why INPO should be writing a SER four days after the incident, not knowing the scope of the problems is mystifying to me.

I spent two years with INPO in the mid 1980 and participated in writing these documents.

George Martin said...

Re: "I've read that hydrogen build-up was also a big concern during the Three Mile Island incident."

We had an hydrogen gas excursion 10 hours following turbine trip at TMI. This was caused by the oxidation of approximately 30% of the zirconium fuel cladding.

The gases escaping through a pressurizer relief valve into the containment building.

Ignition of the gas most likely occurred during the remote cycling of one of these valves.

The maximum pressure to which the building experienced was 28 psig.

These containment buildings were designed for a pressure of about 60 psig, but structurally, should remain intact at twice that pressure.

It was about four days after the accident when our Industry Advisory Group received the Reactor Building pressure strip chart at breakfast and we became aware of it. Although, this information was available on the main control room console, it was not generally known to others.