Tres son los documentos que se han generado:
INITIAL ACRS REVIEW OF: (1) THE NRC NEAR-TERM TASK FORCE
REPORT ON FUKUSHIMA, (2) STAFF’S RECOMMENDED ACTIONS TO BE
TAKEN WITHOUT DELAY (SECY-11-0124), AND (3) STAFF’S
PRIORITIZATION OF RECOMMENDED ACTIONS TO BE TAKEN IN
RESPONSE TO FUKUSHIMA LESSONS LEARNED (SECY-11-0137)
.........................................................................................................
The Honorable Gregory B. Jaczko
Chairman
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001
SUBJECT: INITIAL ACRS REVIEW OF: (1) THE NRC NEAR-TERM TASK FORCE
REPORT ON FUKUSHIMA AND (2) STAFF'S RECOMMENDED ACTIONS TO
BE TAKEN WITHOUT DELAY
Dear Chairman Jaczko:
During the 587th meeting
(si, reunión numero 587, luego me diréis que a estos pajaros no les gustan las convenciones en hoteles de lujo:
of the Advisory Committee on Reactor Safeguards (ACRS), October 6-
8, 2011, we continued our review of the NRC Near-Term Task Force (NTTF) Report on the
Fukushima event [1], "Recommendations for Enhancing Reactor Safety in the 2 1St Century,"
along with the staff's recommended actions to be taken without delay from the NTTF Report [2],
and the staff's report on prioritization of the NTTF recommendations [3]. We were also briefed
on the NTTF Report during our 586" meeting, September 8-10, 2011. We also reviewed
information related to the Fukushima event on April 7, May 26, June 23, July 12, and August 16,
2011. During these reviews, we had the benefit of discussions with representatives of the NRC
staff, the Nuclear Energy Institute (NEI), the Institute for Nuclear Power Operations (INPO), the
Department of Energy (DOE), and members of the public. We also had the benefit of the
documents referenced.
While complete understanding of the Fukushima Dai-ichi accident will take many years, the
NTTF Report and the staff's recommended actions to be taken without delay are appropriately
focused on lessons learned from what is currently known. We believe that none of the
recommendations enumerated herein will be negated, or rendered inappropriate, by the
acquisition of new information. Hence, timely initiation of the staff's recommended actions to be
taken without delay, along with corresponding additions or modifications included herein, is
appropriate.
CONCLUSIONS AND RECOMMENDATIONS
1. The staff's report [2] on recommended actions to be taken without delay from the NTTF
Report identifies immediate actions to be taken. The ***owing additional immediate actions
are recommended:
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a. Actions related to NTTF Recommendation 2.1 should be expanded to include an
expedited update of the applicable regulatory guidance, methods, and data for external
flooding to ensure that outdated guidance and acceptance criteria are not used in the
reevaluations.
b. Actions related to NTTF Recommendation 2.3 should be expanded to assure that the
walkdowns address the integrated effects of severe storms as well as seismic and
flooding events.
c. Actions related to NTTF Recommendation 4.1 should be expanded to include issuance
of an advanced notice of proposed rulemaking and requiring licensees to provide an
assessment of capabilities to cope with an extended station blackout (SBO).
d. Actions related to NTTF Recommendation 5.1 should also be applied to boiling water
reactor (BWR) plants with Mark II containments.
e. Discussions with stakeholders should be initiated regarding near-term actions for
additional hydrogen control and mitigation measures in reactor buildings for plants with
Mark I and Mark II containments.
f. Information should be requested from licensees regarding current plant-specific spent
fuel pool instrumentation, power supplies, and sources of makeup and cooling water.
g. Actions related to NTTF Recommendation 8 should be expanded to include fire
,response procedures.
2. The NTTF Report [11 provides detailed near-term and long-term recommendations for
enhancing nuclear reactor safety based on initial lessons learned from the Fukushima
event. The ***owing additional actions are recommended:
a. Performance-based criteria to mitigate and manage an extended SBO should be
considered as an alternative to the specific coping times proposed in Recommendation
4.1.
b. Recommendation 6 should be expanded to include a requirement for BWR plants with
Mark I and Mark II containments to implement combustible gas control measures in
reactor buildings as a near-term defense-in-depth measure.
c. Recommendation 6 should be expanded to include an assessment of the vulnerabilities
introduced by shared ventilation systems or shared stacks in multi-unit sites.
d. Integration of onsite emergency response capabilities envisioned by Recommendation 8
should be expanded to include fire response procedures.
e. Selected reactor and containment instrumentation should be enhanced to withstand
beyond-design-basis accident conditions.
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f. The NRC should proactively engage in efforts to define and participate in programs to
capture and analyze data from the Fukushima event to enhance understanding of
severe accident phenomena, including BWR melt progression, seawater addition
effects, hydrogen transport and combustion, and safety systems operability.
3. Licensing actions requiring the granting of containment accident pressure (CAP) credit
should be suspended until the implications of post-Fukushima containment pressure control
measures are understood.
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