ML19327B583
| ML19327B583 | |
| Person / Time | |
|---|---|
| Issue date: | 10/24/1989 |
| From: | Baer R NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| To: | Kniel K NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| References | |
| NUDOCS 8911020091 | |
| Download: ML19327B583 (2) | |
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MEMORANDUM FOR:
Karl Kniel, Chief
' Reactor and Plant Safety Issues Branch Division of Safety Issue Resolution Office of Nuclear Regulatory Research FRON:
Robert L. Baer, Chief Engineering Issues Branch Division of Safety Issue Resolution Office of Nuclear Regulatory Research
SUBJECT:
COMMENTS ON NUMARC TECHNICAL REPORT ENTITLED "FRESSURIZED UATER REACTORS CONTAINMENT STRUCTURES; LICENSE RENEWAL INDUSTRY REPORT" General:
The intended purpose of the NUMARC Topical Reports is to address technical life extension issues generically.
EIB is in agreement that generic resolution of.these issues is advantageous for conserving both NRC and
. industry resources. Although EIB has some specific concerns about this first Topical. Report, the use of such reports, approved by NRC, which can be referenced by a Life Extension Applicant, appears to be one viable mechanism for addressing these issues.
Our specific comments are as follows:
- 1..
Ih'the first section of the report, the author (s) conclude that a number of issues are generically resolved and, with a brief caveat, need not be considered further. These conclusions are considered to be too broad to allow the issues outlined to be dismissed generically for all containments.
.The bases for the conclusions are not adequately discussed.
-2.
.The report does not address the issue of loss of tendon prestress based on a 40-year plant life. The Regulatory Guides do not provide guidance for general retensioning of tendons and subsequent tests and inspections after.the containment prestress has been generally exhausted.
3.
There have been a number of conteinments that have experienced degradations and damage over the years.
These should be discussed and analyzed, or reference should be made to an appropriate study.
4.
The description in the NUMARC report of the elements of an ongoing program are vague and do not include schedule recommendations for the conduct of
' tests and inspections. The report should contain recommendations regarding trending of leakage and deterioration during the post-40-year period.
Contact:
- 0. Rothberg, EIB
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.The report dismissed the need for a ntw baseline of tests at the'end of
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the initial plant life. This conclusion should be discussed and justified. Baselining should not be generically dismissed, either
' implicitly or explicitly.
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Robert L. Baer, Chief L
Engineering Issues Branch Division of Safety issue Resolution Office of Nuclear Regulatory Research l-t a
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