It is interesting and sometimes amazing to watch how different people react to different situations. I recall back in April while visiting Singapore, there was the spectacular collapse of the Nicholl Highway – one of the main highways in the country. The expected reports of panic and workers running for their lives followed. But then there was one newspaper report which could only have happened in Singapore. A manager in an office block within view of the collapse calmly began taking pictures of the collapse – not entirely unexpected behaviour. But then instead of perhaps ordering his staff to safety, he instructed them to save their work to floppy disk. Singaporeans – work ethic to a fault.
I couldn’t help but think that the recent accident that took place at the Mihama nuclear power plant could not have happened somewhere like Singapore. Once again, it was in Japan and once again it did Japan’s nuclear industry no favours. Although the accident at Mihama Unit 3 could have happened in any type of power station where there is often high temperature/high pressure steam, it always grabs more public attention when it is at a nuclear plant. More so, when it is in Japan.
Japan’s nuclear industry is already on shaky ground. Mihama has already spurred a public campaign against building more nuclear plants. In 1991 there was a leak of cooling water from reactor number two. Then there was another high profile accident at Tokaimura in 1999. So why can Japan not get it right? It can only be complacency or perhaps they do not realise the gravity of the repercussions. About a third of Japan’s generation comes from nuclear and the continued safe operation of these plants is crucial to the country’s commitments to the Kyoto Protocol.
Mihama Unit 3 is a pressurized water reactor with a rated electric power output of 826 MW and a rated thermal power output of 2440 MW. In initial reports on August 9, Kansai Electric Power Company said the unit was operating at the rated thermal power output when an alarm indicating non-conformance between feedwater and steam flow was actuated. The alarm meant the feedwater to one of the steam turbine generators of the unit was insufficient. This resulted in an automatic reactor trip, followed by an automatic turbine trip. Immediately after the event, the turbine building was filled with steam.
In a more detailed report the following day, Kansai said a fracture had occurred to the condensate piping at a position close to the ceiling of the second level of the turbine building, causing ejection of high temperature water which vaporized and filled the second level of the building with steam. This triggered a fire alarm at 15:22 and caused variations in the plant parameters which in turn initiated emergency shutdown at 15:26. At the time, some 104 people were in the turbine building. At 15:27, shift operators discovered workers collapsing inside the building and started carrying victims out from the building. The first ambulance was called at 15:30. Kansai Electric employees accompanied by fire fighters checked the building until 19:00 to ensure that no one was left inside. Eleven people were injured; four of them fatally.
It is ironic that the piece of pipework was scheduled for checking just days later. In April 2003, Kansai Electric’s cooperating company checked the list management system and found the affected region of piping as being unregistered. Subsequently, the relevant region was scheduled for inspection during the 21st periodical outage scheduled for August 14th, 2004.
Following the accident, the Fukui Prefectural government ordered Kansai Electric to sequentially shut down all of its nuclear power plants and systematically check the integrity of the portions of the systems which are similar to the region that caused the accident at Mihama. Kansai Electric will also check the inspection records of other plants. If any locations are identified as having no inspection record Kansai Electric “will urgently carry out safety inspections on relevant regions”. During the investigations, inspectors approaching any uninspected area will “ensure safety by all means such as wearing fireproof outfits”.
It will take more than firesuits and retrospective action to turn around what is becoming a battered and chaotic image of Japan’s nuclear power sector. I have an old school friend, Jerry Hinds, who now lives in Singapore – a very talented artist with a vivid imagination and a talent for giving sometimes unusual, but apt graphic accounts of situations. Describing the Singapore road collapse he exclaimed: “… it looked like the Hulk passed through there!” When I eventually saw the newspaper pictures, I could not think of a better description. I wonder what Jerry would have said about what must have been a chaotic scene at Mihama.
Junior Isles, Publisher & Editorial Director