1. Compliance of BWRs with New Regulatory Standards
Reviewing the compliance of Japanese boiling water reactors (BWRs) with new regulatory standards involves reviewing the reactor installation license (or its amendment), the construction plans and the operational safety program in relation to standards which have been strengthened in light of the lessons learned from the Fukushima Daiichi nuclear disaster. For the BWRs that are currently undergoing a review of their installation license (or its amendment), measures to ensure compliance with the new regulatory standards and improve safety are being implemented at a quick pace. Those consist mainly of countermeasures against natural disasters, such as reinforced earthquake protection for facilities of high safety importance, measures for dealing with major accidents, such as the installation of the filtered containment venting facility, and countermeasures against terrorist attacks, such as aircraft impact protection. The Hitachi Group has been involved in this process at every stage, from new technological development to design and construction, committing thorough efforts for implementing the measures against such broad variety of severe accidents.
Hitachi has also developed sophisticated assessment technology to evaluate the effectiveness of these measures including probabilistic safety assessment and severe accident analysis, and has therefore significantly contributed to the improvement of the evaluation technology demonstrating the effectiveness of those countermeasures.
Out of a total of ten reactors that have applied for reactor licenses with the Hitachi Group’s support, six are currently in the process of having their licenses or their amendments reviewed. This figure includes the No. 6 and No. 7 reactors at Tokyo Electric Power Company Holdings’ Kashiwazaki-Kariwa Nuclear Power Station. Hitachi will continue providing utmost support for the safety screening of BWRs and helping further improve nuclear power plants’ safety through the development of safe technology.
1. Measures to prevent core damage and containment vessel damage at BWRs