Surry Nuclear Plant. Nuclear Generation at Dominion Power.Fukushima Daiichi Nuclear Plant Events.

Meeting: Monday, March 28, 2011

Craig T. Olsen with Dominion Generation honored us with his presence to talk about the recent tragedy in Japan. He explained the sequence of events at the Fukushima Daiichi Nuclear Plant. 

There are two types of reactor designs: boiling water reactors and pressurized water reactors. All the reactors in the US are either BWR or PWR. Fukushima Daiichi is a GE boiling water reactor, whereas the Dominion sites are Westinghouse & Combusting Engrg Pressurized Water Reactors. 
Japan has 54 operating nuclear reactors, which is half of the nuclear power that the United States has.

The earthquake is Japan had a magnitude of 9.0. The unprecedented quake created a tsunami greater than 14 meters (approximately 46 feet) above the sea level. Despite the incredible force, the Fukushima emergency response systems operated as planned immediately after the earthquake. It was the subsequent tsunami that put the stations' backup power out of commission and led to the current circumstances. 


The tsunami was larger than what the plant was designed for, so it took out all multiple sets of the backup emergency diesel generators. Reactor operators were able to utilize emergency battery power to provide power for cooling the core for 8 hours. Offsite power could not be restored and delays occurred obtaining and connecting portable generators. 


Reactor temperatures increased and water levels in the reactor decreased, eventually uncovering and overheating the core. The metal-water reactions in the reactor produced hydrogen which was most likely ignited by a spark.


Further, Mr. Olsen gave us a technical overview of the source of radioactive material, hydrogen detonation, and the source of hydrogen, along with Fukushima mitigation actions.


The potential radiation impact on the United States is not considered to be serious."The annual dose from this radiation level is equivalent to the dose from eating less than 4 percent of a banana – assuming you could slice it that small."- says Mr. Olsen.


Dominion reacted immediately to the tragedy in Japan by offering equipment, material and knowledge from Millstone Unit 1 to the Japanese nuclear industry. As far as Dominion safety measures are concerned, procedures are in place to respond to events including abnormal operating procedures, emergency operating procedures, and severe accident management guidelines. Dominion demonstrates the highest levels of safety and reliability in the operation of its nuclear power plants.


On Monday, we had three guests: Pjerin Luli with Dilon Diagnostics, Chris Morello from the Newport News Development Department and John Leyden from the Warwick High School. It was great to have you and we hope to see you soon.


The raffle has not been won in weeks. They say that the more tickets you buy, the more chances you have to win big, so don't be shy on Monday!