ML19344E589
| ML19344E589 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 08/15/1980 |
| From: | Eisenhut D Office of Nuclear Reactor Regulation |
| To: | Counsil W NORTHEAST NUCLEAR ENERGY CO. |
| References | |
| NUDOCS 8009020311 | |
| Download: ML19344E589 (4) | |
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Docket No. 50-245 August 15, 1980 Mr. W. G. Counsil Vice President, Nuclear Engineering and Operations Northeast Nuclear Energy Company P.O. Box 270 Hartford, Connecticut 06101
Dear Mr. Counsil:
Subject:
IREP Schedule At our meeting on August 4 we promised to send you an outline of the IREP schedule for the first 5 months annotated,to highlight the skills and knowledge that could best be provided by your representative (s) on the IREP team. The anticipated start date is September 15, 1980. The following discussion refers to the IREP Procedure and Schedule Guide, to my letter of July 25, 1980.
First 2 weeks - First cut at tasks 1-5, late September. The team will be f amiliarizing itself with the plant documentation and perfonning the first few t' asks in the IREP Procedure and Schedule Guide. We anticipate a number of document requests to be made from the procedure index or diagram index. Someone thomughly familia with the plant design and operations documentation would help the team to be selective and to request the appropriate documents.
Third through eighth week - First cut at tasks 6-17, October and early November. The team will be classifying initiating events, developing the catalogs of accident scenarios in broad outline (event tree analysis),
defining system success vs. failure criteria, and tracing the possible causes of the initiating events to faults in the support systems which also serve the required mitigating systems. During this phase, the assistance of an individual who has a broad understanding of accident processes, systems design, and operation would be particularly valuable.
We have not requested the voluminous plant design documentation on power generation equipment that may prove to be necessary to perfonn the fault tree analyses of transient initiators and non-passive failure LOCAs.
Therefore, we will probably assign to the more knowledgeable owner's representative the lead responsibility for the development of the fault trees for the initiating events. He will also be expected to partici-pate in each of the other tasks: event tree analysis, definition of the system success vs. failure criteria, etc.
80090203);
AUG 151980 Mr. W. G. Counsil Ninth through sixteenth week - First cut at tasks 18-27, late November through January. This phase of the study will focus on fleshing out the reliability-predictive models of the systems (fault tree analysis). The Nit to the plant by the team will occur late in the prior phase or early in this phase. We anticipate that the early wrk in this phase will concentrate on the relatively straight-fomard front line engineered safety features.
In the later phase the work will move to the modeling of the network of support systems. We expect a progressively growing need for owner's representative assistance to the team within this interval in the conteyts of (1) surveillance and maintenance practices,
(?) operating and emergency procedures, and (3) control and instrumentation.
S: 1eenth through twentieth week - First cut at tasks 28-35, February.
The initial screening of accident scenarios according to likelihood and the search for not-yet-identified common cause failure modes will take place in this interval.
Particularly useful know! edge and skills in your representatives will be in the areas of possible operator corrective action in the face of multiple failures, control and instrumentation, and procedures.
In this and successive phases the team will be refining their models of the potentially dominant accident scenarios. The questions the team will need to ask of your personnel will be more sharply focused. The physical presence on the team of the more knowledgeable and valuable personnel will be less important than in the formative second phase (weeks 2-8).
You will, however, want to keep your more senior people in engineering and operations apprised of the emerging picture of the dominant accident sequences. You may want to intersperse the occasional management briefings with more frequent technical briefings during the last few months of the program.
From our point of view, we would prefer as much continuity, knowledge, and skill as we can get in your participants. We do understand, though, that your better people are in great demand.
If I were in your shoes and could manage it I would assign a junior systems and licensing engineer or systems reliability engineer to stay with the IREP team throughout. He or she would be in it for the experience, for liaison, and to take a prominent mle in the digestion and use of the results at the conclusion of the IREP study. He or she might be eamarked to exercise and keep the IREP models updated after the NRC study is complete, as Florida Power Corporation is planning to do.
I would select that person for imagination, sound abstract thinking or broad overview, and at least a passing familiarity with mechanical, electrical and control systems engineering. That person should also have the facility with mathematics to rapidly learn probabilistic system reliability analysis while on the team.
In addition to this continuous presence on the IREP team, I would assign a couple of others for temporary assignment to IREP.
I would pick the most knowledgeable individual I could pry loose in plant operations and engineering for the 6 week second phase period I
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tr.11. G. Counsil AtJG 151930 in October and ibyenber (event trees, system success criteria, and the analysis of initiating events).
I wuld try to eamark i day per week of this same person's time from February through the conclusion of the study - while he or she remains at their norral rest - to review tN convergence on results. A third person, chosen for familiarity with control and instrtcentation, maintenance procedures and energency procedures sculd be detailed to IREP in January and February (late in the system reliability codeling phase and the subsequent probabilistic cvaluations) to assure that the rodeling of the netwrk of support systens is donc correctly, to participate in the evaluation of ecuip'ent unavailability due to test and r.aintenance, and to assist in rudeling the possibilities for operator corrective action during accidents. That person, too, I wuld assign to part time review of IREP results after their return to norral assign ant in flarch. To r.ake sure that person can get up to srcad pronptly when he or she joins the team in January, that p:rson should have attended - as a minimum - an engincering short course in proSabilistic system reliability analysis or fault trea analysis.
This representation, one person full tice and tw rare highly-cualified pecple for 6 mek assignments should rect our rutual need to assure that the rodels produced in IREP fairly cortray your plant and offer your people censiderable experience in probabilistic safety analysis without unculy burdening your already hard pressed staff, or so m believe.
I hora that this helps you in your planning for IREP participation.
Sincerely, Original signed bw Darrell G* E13erNat Carrell G. Eisenhut, Director Division of Licensipg Office of I'uclear Reactor Regulation cc:
See Attached List bec: Docket File NRC Public Document Room J. Shea R. Mattson M. Ernst S. Israel F. Rowsome J. !!urphy i
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- Northeast Nuclear Energy Company cc:
Mr. John Shediosky Mr. Robert McGuinness Resident Inspector / Millstone Northeast Nuclear Energy Co.
C/o U.S. NRC P. O. Box 270 P. O. Drawer KK Hartford, CT 06101,
Niantic, CT 06357 William H. Cuddy, Esq Mr. Charles B. Brinkman, Manager Day, Berry & Howard Washington Nuclear Operations Counselors at Law C-E Power Systems One Constitution Plaza Combustion Engineering, Inc.
Hartford, CT 06103 4853 Cordell Ave., Suite A-1 Bethesda, MD 20014 Anthony Z. Rosiman Natural Resources Defense Council Connecticut Energy Agency 917 15th Street, NW Attn: Assistant Director,Research Washington, DC 20005 and Policy Development Department of Planning and Energy Pol Mr. Lawrence Bettencourt, 20 Grand Street First Selectman Hartford, CT 06106 Town of Waterford Hall of Records Mr. Robert Szalay, Licensing and 200 Boston Post Road Safety Project Manager Watterford, CT 06385 American Industrial Forum 7101 Wisconsin Avenue Northeast Nuclear Energy Company Attn: Superintendent, Millstone Plant Washington, DC C0014 i
P. O. Box 128 Mr. E. P. O'Donnell Ebasco Services, Inc.
Waterford, CT 06385 89th Floor U.S. Environmental Protection Agency Director, Technical Assessment Division 2 World Trade Center Off. ice of Radiation Program (AW-459)
New York, NY 10048 Crystal Fall #2 Dr. Edwin Zebroski Arlington, VA 20460 Nuclear Safety Analysis Center U.S. Environmental Protection Agency 3412 Hillview Avenue P. O. Box 10412 Region I Office Palo Alto, CA 94303 Attn:
EIS Coordinator John F. Kennedy Federal Building Boston, MA 02203 Northeast Utilities Services Co.
Attn: Mr. James R. Himmelwright Waterford Public Library Nuclear Engineering and Operations Rape Ferry, Route 156 P. O. Box 270 Waterford, CT 06385 Hartford, CT 06101 l
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