4 JAPAN’S NUCLEAR SAFETY REGULATION POLICY
85
Commissioner, external experts selected in line with the neutrality criteria,
NRA Secretariat officials, and sometimes members of so-called incorporated administrative agencies or semi-private research institutes, such as
the Japan Atomic Energy Agency (JAEA). New safety requirements for
commercial nuclear power plants were adopted by the NRA Commission, issued in June 2013 and went into force on July 8. For nuclear fuel
cycle facilities, the NRA decided to take a graded approach, meaning that
new regulatory requirements will be developed for each facility due to
vast differences in construction design (NRA 2014a).
The new safety regulation introduced several innovations. These can
be subsumed under the following umbrella terms, each of which will be
explained in detail hereafter: a forty-year rule, a back-fit system, defencein-depth, and severe accident countermeasures (NRA 2013a). First, the
NRA incorporated a forty-year rule limiting a reactor’s lifespan into the
new safety regulations, meaning that an operating licence is only granted
for 40 years. If a plant operator wishes to operate a reactor for longer,
they can apply for a one-time extension of 20 years. Such an extension
is tied to a renewed safety review to determine whether the reactor is fit
for another 20 years in operation. This is the area where the Abe government exerted pressure on the NRA to relax the forty-year rule and to
let reactors operate for 60 years. This is presumably because the 20–
22% target for nuclear power in the 2030 energy mix, adopted by the
Abe government, is only possible if reactors generally have their lifespan
extended.
The back-fit system means that updating reactors in line with new scientific developments is not at the discretion of electricity utilities anymore.
Now, plant operators not only have to conform to a given set of safety
standards when they commission the plant, but also need to update them
in line with adjustments in regulation over time. This forms the basis for
the currently undertaken reactor review. It is a safety review to make sure
that reactors which were already in operation are back-fitted in accordance
with NRA regulation. The back-fit system and the 40-year limit provide
the NRA with leverage over the industry. In stark contrast to its predecessor, which had to rely on the industry following its recommendations,
the NRA can ensure compliance by threatening to resolve the operating
licence of a nuclear reactor in case of non-compliance.
The concept of defence-in-depth is related to predefined threats that a
nuclear power plant needs to be able to withstand. Previous safety requirements assumed that a single function or component within a reactor
85
Commissioner, external experts selected in line with the neutrality criteria,
NRA Secretariat officials, and sometimes members of so-called incorporated administrative agencies or semi-private research institutes, such as
the Japan Atomic Energy Agency (JAEA). New safety requirements for
commercial nuclear power plants were adopted by the NRA Commission, issued in June 2013 and went into force on July 8. For nuclear fuel
cycle facilities, the NRA decided to take a graded approach, meaning that
new regulatory requirements will be developed for each facility due to
vast differences in construction design (NRA 2014a).
The new safety regulation introduced several innovations. These can
be subsumed under the following umbrella terms, each of which will be
explained in detail hereafter: a forty-year rule, a back-fit system, defencein-depth, and severe accident countermeasures (NRA 2013a). First, the
NRA incorporated a forty-year rule limiting a reactor’s lifespan into the
new safety regulations, meaning that an operating licence is only granted
for 40 years. If a plant operator wishes to operate a reactor for longer,
they can apply for a one-time extension of 20 years. Such an extension
is tied to a renewed safety review to determine whether the reactor is fit
for another 20 years in operation. This is the area where the Abe government exerted pressure on the NRA to relax the forty-year rule and to
let reactors operate for 60 years. This is presumably because the 20–
22% target for nuclear power in the 2030 energy mix, adopted by the
Abe government, is only possible if reactors generally have their lifespan
extended.
The back-fit system means that updating reactors in line with new scientific developments is not at the discretion of electricity utilities anymore.
Now, plant operators not only have to conform to a given set of safety
standards when they commission the plant, but also need to update them
in line with adjustments in regulation over time. This forms the basis for
the currently undertaken reactor review. It is a safety review to make sure
that reactors which were already in operation are back-fitted in accordance
with NRA regulation. The back-fit system and the 40-year limit provide
the NRA with leverage over the industry. In stark contrast to its predecessor, which had to rely on the industry following its recommendations,
the NRA can ensure compliance by threatening to resolve the operating
licence of a nuclear reactor in case of non-compliance.
The concept of defence-in-depth is related to predefined threats that a
nuclear power plant needs to be able to withstand. Previous safety requirements assumed that a single function or component within a reactor