ML19305A659
| ML19305A659 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse, Oconee, Arkansas Nuclear, Crystal River, Rancho Seco, Midland, Bellefonte, 05000514, 05000515, 05000453, 05000580, 05000581, Crane  |
| Issue date: | 09/13/1979 |
| From: | Fraley R Advisory Committee on Reactor Safeguards |
| To: | Rogovin M NRC - NRC THREE MILE ISLAND TASK FORCE |
| Shared Package | |
| ML19305A660 | List: |
| References | |
| TASK-TF, TASK-TMR NUDOCS 8001160712 | |
| Download: ML19305A659 (4) | |
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[g a g#'o, UNITED STATES y ; 3, j
NUCLEAR REGULATORY COMMISSION g
c c ADVISORY COMMITTEF ON REACTOR SAFEGUARDS o,
g WASHING TON, D. C. 20555 September 13, 1979 Mr. Mitchell Rogovin, Director NRC/TMI Special Inquiry Group U. S. Nuclear Regulatory Commission Washington, D.C.
20555
Dear Mr. Rogovin:
The following information is provided in partial response to your quu v..
9 aire of August 7, 1979 which was sent to ACRS members and me.
This infor-nition is based on a review of ACRS records and provides information where a,propriate documentation exists. Members of the Committee will be available tc. provide individual comments and opinions during a meeting scheduled for October 6,1979 between the Special Inquiry Group and the members of the Com-
\\
mittee as requested by members of your staff.
A.
PERSONAL BACKGROUND The personal background information requested in item A of your letter is in-cluded in Attachment A.
In addition to the current membership of the Commit-tee, I have included those members who were active when the B&W facilities listed in Attachment B were reviewed.
The terms of appointment of members and Committee officers are as noted.
In addition, all ACRS members serve as subcommittee chairmen and members on a variety of standing and ad hoc ACRS Subcommittees with responsibilities regarding specific project reviews and a number of generic safety related matters.
B.
Involvement with Licensing of B&W Plants The ACRS must, by statute, review and advise the NRC on all applications for Construction Permits, and Operating Licenses for all commercial nuclear power plants as well as Preliminary Design Approvals, Manufacturing Licenses, etc.,
for standardized plants.
Consequently, the Committee has been involved in all such proceedings in which a Babcock and Wilcox design was at issue. A list is included in Attachment B.
The involvement of any individual Committee member in any of the proj; cts listed would have aepended on the dates of his appoint-ment and termination as an Advisory Committee Member.
The ACRS review process normally involves discussions with representatives of the applicant, reactor vendor, architect-engineer, and selected sub-contractors and consultants as well as the NRC Staff and its consultants.
In addition, the application as well as other related documents including the NRC Staff Safety Evaluation Report (SER) are also considered.
Follawing its revien of each proposed project the ACRS provides a report to the Commission which includes ACRS recommendations regarding needed changes and res-olution of outstanting safety related issues.
8001'607(
0 4
3 Mr. Mitchell Rogovin. September 13, 1979 In most cases, ACRS Subcommittee and full Committee activity on project pro-posals begins when the radiological' safety review of the NRC Staff is largely complete and a Safety Evaluation Report (SER) has been written, but precedes the radiological safety portion of the ASSLB hearing. Responses to Committee comments and recommendations in its report to the Commission are included in a Supplement to the SER which is issued by the NRC Staff and addresses the actions to be taken regarding ACRS recommendations.
This supplemental SER is
-made part of the record of the proceeding so it is available to the Hearing Board in its consideration of a case. Copies are made available to the ACRS for information.
Sumaries of significant issues discussed-during the ACRS review of proposals involving a B&W design are included in Attachment B.
The attachment also in-cludes summaries of matters of particular concern to the ACRS as noted in its reports to the Commission, and their disposition by the Regulatory Staff as described in Supplements to SERs, special memoranda from the Staff, oral pres-entations at ACRS Full Committee and Subcommittee meetings, etc.
C.
General Observations The ACRS has recently begun its own in-depth examination of the NRC regulatu,j policies and practices as well as the basis and procedures for evaluation of proposed nuclear facilities.
Since this evaluation is in its initial stages the Committee is unable at' this time to respond in a comprehensive way to your questions in this category.
Nevertheless the Committee is of the opinion that the NRC Staff's perfonnance'in the licensing process generally demonstrates a substantial degree of technical competence.
At the same time, there have been specific issues about which the Committee has not been fully satisfied. As was noted in the July 25, 1979 letter from Dr. Carbon to Mr. Rogovin,'the Committeef believes that responses to its recommendations concerning " instrumentation to -
follow the course of an accident" have not been adequate.
There are several other examples about which the Committee would have preferred a more effective response-on the part of the Commission Staff. Among the more significant of these are:
. Timeliness of Responses to ACRS Recommendations - attached, as an example, is an excerpt from an OPE report,-approved by the Com-
. mission, and two ACRS Reports on the Zion Station which were the basis for the OPE resort.
(See Attachment C.1)
.,Consideraton of Design Changes to Mitigate Sabotage - This matter, which goes beyond access control (the main thrust of the Commis-sion's anti-sabotage effort), was first raised in a Committee report to the Chairman dated October 14, 1975. That and sub-sequent reports on the subject are included, as well-as excerpts from the Committee's reports to the Congress on the RSR program of 1977 and 1978, indicatirj that a serious study of some aspects L
of this matter has only la',ely been undertaken.
(SeeAttachment h =_
C.2)
N Mr. Mitchell Rogovin September 13, 1979
~
. Consideration of Accidents Beyond the Limits of the Regulatory Design Basis Accider.t - The Committee has, on a number of occa-sions extending over a long period, recommended consideration of the consequences of accidents beyond the design basis, and means of. ameliorating them.
Indeed, the question of instrumen-tation to follow the course of an accident, noted above, is just such an issue. Other matters in this category include means for retaining molten fuel, and the consideration of evacuation plans for people located outside the LPZ as defined in Part 100. Both issues are summarized in the material attached which contains excerpts from ACRS reports beginning in 1971 and culminating with the Committee's 1979 Comments on the NRC Safety Research Program.
Budget ~.
(See Attachment C.3)
.More Widespread Use of Probabilistic Analysis - For some time the Committee has been urging more widespread use of probabilistic methodologies in the regulatory process.
Examples are attached; the latest, an excerpt from the Committee's 1979 Comments on the NRC Safety Research Program Budget, suggests that this goal has not yet been fully realized.
(See Attachment C.4)
L D.
Issues for Further Scrutiny The ACRS has provided the NRC with written and oral advice on some matters which it believes to be particularly significant in view of the accident at Three Mile Island and its implications.
Copies of the ACRS Reports on these
- matters are attached.
(See Attachment D.1)
With regard to events which might be considered " precursors" to t e accident S
at Three Mile Island, the Committee had discussed the following such events with the NRC Staff:
1.
Oconee Unit 3 - June 13,1975 ICS failed to follow load demand-below 15% power; PORV opened at 2255 psi and failed to close.
Reactor tripped on low pres-sure; HPCI actuated and PORV isolation valve was closed to terminate depressurization.
This was described by and dis-cussed with the NRC Staff during the 183rd ACRS meeting, July 10-12, 1975 2.
Davis Besse Unit 1 - September 24, 1977 A half trip of the steam and feedwater rupture control system resulted in PORY opening, cycling, and sticking open.
The operator manually tripped the reactor and ultimately isolated the PORV. - Additional elements of this event included the
'fonnation of a steam bubble within the RCS, an upsurge of the 4
Mr. Mitchell Rogovin ~ September 13, 1979
-level in the pressurizer, and rupture of the rupture disc in the -
Pressurizer Quench Tank with consequent release of steam to the containment. This event was described by and discussed with the NRC Staff during the 210th and 211th ACRS meetings, October 6-8 and November 3-5, 1977.
(See Attachment D.2)
E.
Comments
- As.noted above, the Committee 'l.s recently begun an evaluation of the regulatory process and the key elements favolved in this process.
As Committee conclusions
. result from this-study. they will be made available to the Special Inquiry Group as'well as the Nuclear Regulatory Commission.
R. F. Fraley l
Executive Director
Enclosures:
~ A) Personal Background B)
Involvement with Licensing of B&W Plants C) -General Observations D)
Issues for Further Scrutiny
' cc: ACRS Members 4
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