studying the detailed causes of the 2011 accident at Fukushima Daiichi nuclear plant

Japan's Nuclear Regulation Authority is studying the detailed causes of the 2011 accident at Fukushima Daiichi nuclear plant. It plans to incorporate the findings into new safety standards for nuclear power stations.On Wednesday, 19 employees of the authority and outside experts held an initial meeting of the study team. Their goal is to clear up the many questions that remain even after fact-finding groups from the government, the Diet and the plant's operator all published reports on the accident.An official from the nuclear authority briefed the team on the main points of investigation -- namely, the impact of the earthquake, how the fuel rods melted, and how radioactive material leaked.These issues gave rise to questions that remain unanswered, as high levels of radiation have hampered on-site investigations at the plant.The group then discussed the unexplained water leak that occurred in the No.1 reactor building immediately after the quake.The plant's operator, Tokyo Electric Power Company, has said that water from the pool for spent fuel trickled down through the air conditioning system.The experts at the meeting called for further study on whether the cooling system was disabled by the quake, and whether the air conditioning system was damaged by the quake itself or by pressure from the leaked water.The team hopes to pinpoint as many facts as possible through its investigation, including on-site surveys.

May. 1, 2013 - Updated 12:53

Au Japon, l'Autorité de régulation du nucléaire, l'ARN, étudie en détail les causes de l'accident à la centrale nucléaire Fukushima Dai-ichi en 2011.

19 employés de l'ARN et des experts indépendants ont procédé mercredi à la réunion inaugurale de leur groupe d'étude. Leur objectif est d'éclaircir les nombreuses questions qui subsistent, même si les commissions d'enquête du gouvernement, de la Diète et de l'opérateur ont déjà toutes publié des rapports sur cet accident.

Un responsable de l'organe a informé l'équipe des principaux points de l'enquête, c'est-à-dire l'impact du séisme, mais aussi comment les barres de combustible ont fondu et comment des matériaux radioactifs ont fui.

Ces questions ont donné lieu à d'autres interrogations qui sont restées sans réponses, car le fort niveau de radioactivité a empêché de mener l'enquête sur le site.