[Federal Register Volume 66, Number 86 (Thursday, May 3, 2001)]
[Notices]
[Pages 22269-22270]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-11113]


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NUCLEAR REGULATORY COMMISSION


NUREG-1742, ``Perspectives Gained From the Individual Plant 
Examination of External Events (IPEEE) Program''; Draft for Comment

AGENCY: Nuclear Regulatory Commission.

ACTION: Notice of availability of the draft report for comment NUREG-
1742, ``Perspectives Gained from the Individual Plant Examination of 
External Events (IPEEE) Program''.

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SUMMARY: The Nuclear Regulatory Commission issued on June 28, 1991, 
Supplement 4 to Generic Letter 88-20, ``Individual Plant Examination of 
External Events (IPEEE) for Severe Accident Vulnerabilities, 10 CFR 
50.54(f).'' Associated guidance for conduct of the IPEEEs was issued in 
June 1991 in NUREG-1407, ``Procedural and Submittal Guidance for the 
Individual Plant Examination of External Events (IPEEE) for Severe 
Accident Vulnerabilities.'' Specifically, the Nuclear Regulatory 
Commission requested that each licensee perform an IPEEE to identify 
and report to the Nuclear Regulatory Commission all plant-specific 
vulnerabilities to severe accidents caused by external events. This 
review was limited to plant behavior under full-power operating 
conditions. The external events to be considered included seismic 
events; internal fires; and high winds, floods, and other (HFO) 
external initiating events including transportation or nearby facility 
accidents and plant-unique hazards. All currently operating nuclear 
power plants in the United States have completed their assessments and 
submitted their analyses to the NRC.
    Consistent with the intent of Generic Letter 88-20, the primary 
goal of the IPEEE program has been for each licensee to identify plant-
specific vulnerabilities to severe accidents. More specifically, 
Supplement 4 to Generic Letter 88-20 identified the following four 
objectives for the IPEEE:
     To develop an appreciation of severe accident behavior,
     To understand the most likely severe accident sequences 
that could occur at the licensee's plant under full-power operating 
conditions,
     To gain a qualitative understanding of the overall 
likelihood of core damage and fission product releases, and
     To reduce, if necessary, the overall likelihood of core 
damage and radioactive material releases by modifying, where 
appropriate, hardware and procedures that would help prevent or 
mitigate severe accidents.
    The primary objective of the NRC's technical review process was to 
ascertain the extent to which the licensee's IPEEE submittals have 
achieved the intent of Generic Letter 88-20, satisfied the four 
principle IPEEE objectives listed above, and followed the recommended 
guidance in NUREG-1407. The reviews focused on verifying that the 
critical elements of acceptable IPEEE analyses in the fire, seismic, 
and HFO areas were performed in accordance with the guidelines in 
NUREG-1407. Results of the reviews of each IPEEE are documented in 
plant-specific Staff Evaluation Reports and Technical Evaluation 
Reports which were transmitted to each licensee and made publically 
available. It should also be noted that the staff's reviews were not 
intended to validate or verify the licensees' IPEEEs analyses or 
results (i.e., an in-depth evaluation of the various inputs, 
assumptions, and calculations was not performed). Rather, methods, 
approaches, assumptions, and results were reviewed for reasonableness. 
If inconsistencies were encountered, they were reported in the plant-
specific IPEEE Technical Evaluation Reports.
    The draft report NUREG-1742, ``Perspectives Gained from the 
Individual Plant Examination of External Events (IPEEE) Program'' 
summarizes the findings from the review of the licensees' IPEEE 
submittals. The public is invited to provide feedback on this draft 
report.
    As part of the IPEEE program, some generic issues were addressed by 
the licensees in their submittals. As noted in draft NUREG-1742, while 
this has resulted in resolution of most of the generic issues related 
to the IPEEE program, some aspects of some generic issues were not 
sufficiently discussed in all submittals to reach a resolution. Those 
remaining issues will be addressed separately from the IPEEE program.

SUPPLEMENTARY INFORMATION: This notice serves as a request for public 
comment on the Nuclear Regulatory Commission's draft report NUREG-1742, 
``Perspectives Gained from the Individual Plant Examination of External 
Events (IPEEE) Program,'' that is dated April 2001 (web address: 
http://www.nrc.gov/NRC/NUREGS/SR1742/V1/index.html). Only written 
comments are requested. Feedback is especially requested on the 
following specific questions.
    1. Does the information contained in NUREG-1742 represent a useful 
understanding of the potential vulnerabilities of nuclear power plants 
to external events? How will the information in this report be used by 
various stakeholders? What would make the information more useful?
    2. Are there another comparisons of information from the IPEEE 
submittals that would yield useful insights? If so, what comparisons 
would be useful? Why?
    3. Given the information from the IPEEE submittals on the risk from 
fire, seismic and other external events, is additional research needed 
to improve methods, reduce uncertainties, or resolve issues? If so, 
what research should be pursued and why? If not, why not?
    4. Potential plant improvements, identified by licensees in their

[[Page 22270]]

submittals, can be divided into three general categories--improvements 
that (1) have been completed, (2) will be made, or (3) will receive 
further consideration. Are there any improvements in either of the last 
two categories that have been completed and that resulted in a 
significant change in a plant's ability to withstand potential external 
events? If so, what are the improvements and the related changes to the 
plant's capability?
    5. How can the results of the IPEEE program be used to (1) maintain 
safe operations of nuclear facilities; (2) make NRC activities and 
decisions more effective, efficient, and reliable; (3) increase public 
confidence; or (4) reduce unnecessary regulatory burden on 
stakeholders?

FOR FURTHER INFORMATION CONTACT: Written comments may be sent to Dr. 
Alan M. Rubin, Probabilistic Risk Analysis Branch, Division of Risk 
Analysis and Applications, Office of Nuclear Regulatory Research, Mail 
Stop T10E50, U.S. Nuclear Regulatory Commission, Washington, DC 20555, 
or e-mail: [email protected].


DATES: Submit comments by July 31, 2001. Comments received after this 
date will be considered if it is practical to do so, but the Commission 
is able to ensure consideration only for comments received on or before 
this date.

    Dated this 10th Day of April 2001.

    For the Nuclear Regulatory Commission.
Thomas L. King,
Director, Division of Risk Analysis and Applications, Office of Nuclear 
Regulatory Research.
[FR Doc. 01-11113 Filed 5-2-01; 8:45 am]
BILLING CODE 7590-01-U