Transcript Slide 1

Fukushima
Regulatory Impacts
NRC Region I Spring Seminar
May 13, 2014
Dave Lochbaum
Director, Nuclear Safety Project
Union of Concerned Scientists
Fukushima - Many Barriers
• Multiple connections to offsite power grid
• Two emergency diesel generators per unit
• Eight hour battery backups to grid and EDGs
• 15-foot tall seawall
• Multiple onsite fire trucks with diesel pumps
• Severe accident management guidelines
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Fukushima - More Barrier Busters
• Multiple connections to offsite power grid
9.0 earthquake took away grid
• Two emergency diesel generators per unit
Located in basements vulnerable to floods
• Eight hour battery backups to grid and EDGs
Onsite power outage lasted 9 days
• 15-foot tall seawall
45-foot tall tsunami wave
• Multiple onsite fire trucks with diesel pumps
Infrastructure damage impaired use
• Severe accident management guidelines
Good on paper (and only on paper)
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Fukushima – One Barrier Shy
Fukushima had many barriers.
Had just one barrier been sufficiently
robust, we wouldn’t be here today
discussing Fukushima.
More importantly, had just one barrier
been sufficiently robust, tens of
thousands of Japanese civilians would be
home today instead of being displaced.
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Disconnected Safety Regimes
NTTF Recommendation 1
EPGs/SAMGs
FLEX
PRAs
Really just one disconnection with three
consequences from this disconnection.
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Disconnected Safety Regimes
NTTF’s foremost
recommendation:
Commission moved
Recommendation 1
to last place
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Disconnected Safety Regimes
EPGs
SAMGs
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Disconnected Safety Regimes
Regulatory
requirements for
safety-related
SSCs
Hopes about
FLEX
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Disconnected Safety Regimes
PRAs for
design basis
accidents
Fond wishes
for severe
accidents
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Disconnected Safety Regimes – NTTF 1
One way to deal with “cliff-edge”
effects is to pretend there are none
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Disconnected Safety Regimes – NTTF 1
Commissioner Magwood during March 15,
2012, Senate oversight hearing:
I think that our infrastructure, our regulatory
approach, our practices at plants, our
equipment, our configuration, our design
bases would prevent Fukushima from
occurring under similar circumstances at a
U.S. plant. I just don’t think it would happen.
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Disconnected Safety Regimes – NTTF 1
Commissioner Apostolakis during March 15,
2012, Senate oversight hearing:
I don’t think what happened in Fukushima
can happen here.
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Connected Safety Regimes – NTTF 1
A better way is to accept cliffs exist
and to manage their hazards
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Connected Safety Regimes – NTTF 1
Someone should remind Commissioners
Thelma and Louise about the cliff-edge
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Disconnected Safety Regimes – NTTF 1
NRC November 2013 report “A Comparison of
U.S. and Japanese regulatory requirements in
effect at the time of the Fukushima accident”
(ML13326A991), page 20:
Prior to the Fukushima accident, both
Japanese regulators and industry publicly
stated that the possibility of severe accidents
was sufficiently low, to the extent that a
severe accident could not occur from an
engineering viewpoint.
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Disconnected Safety Regimes – NTTF 1
NRC November 2013 report “A Comparison of
U.S. and Japanese regulatory requirements in
effect at the time of the Fukushima accident”
(ML13326A991), page 3:
Staff cautions, however, that there should be
no implication that the Fukushima accident
and associated consequences could or would
have been completely avoided assuming
Japan had the same U.S. regulatory
framework prior to the accident.
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Connected Safety Regimes – NTTF 1
NTTF’s foremost
recommendation:
Establishes regulatory footprints for design bases
and beyond design bases events
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Connected Safety Regimes – NTTF 1
Template for viable NTTF 1 connection
between design basis and beyond design
basis might be operator licensing.
NRC will license/relicense reactor
operators and senior reactor operators.
Under NRC-established conditions
monitored by NRC, licensees can perform
some of this testing.
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Connected Safety Regimes – NTTF 1
There must be a regulatory footprint for design
basis and beyond design basis measures.
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Disconnected Safety Regimes - SAMGs
• 100% developed SAMGs
• 89% had SAMGs in control rooms
• 72% had SAMGs in EOFs
• 92% trained workers on SAMGs
• 77% re-trained workers on SAMGs
• 75% required SAMGs to reflect plant mods
• 42% had configuration mgmt for SAMGs
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Disconnected Safety Regimes - SAMGs
SAMGs protect the public during a severe
accident – unless a severe accident occurs
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Connected Safety Regimes - SAMGs
NRC inspects requirements, not voluntarisms
NRC finds compliances, or issues sanctions
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Disconnected Safety Regimes - FLEX
• 100% develop FLEX
• ??% have adequate quality standards for FLEX
• ??% have adequate testing standards for FLEX
• ??% train workers on FLEX
• ??% re-train workers on FLEX
• ??% require FLEX to reflect plant mods
• ??% have configuration mgmt for FLEX
FLEX protects the public during a severe
accident – unless a severe accident occurs
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Disconnected Safety Regimes - PRAs
PRAs
For the RA to truly stand for risk
assessment, the P cannot stand for:
- partial
- pretend
- pseudo
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Connected Safety Regimes - PRAs
PRAs
must cover all modes of operation, all
transients, and all accidents (not just
those that follow design basis scripts)
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Are we there yet?
NTTF recommended nearly 3 dozen ways
to reduce vulnerabilities at U.S. reactors
Not there yet with even 1 safety IOUs still
outstanding
Not there yet even when ALL of these
safety IOUs are fully and effectively done
Only there if NTTF after next disaster finds
few vulnerabilities left to remedy
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Moving in the right direction,
but clearly not there yet
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