ML20129H987
| ML20129H987 | |
| Person / Time | |
|---|---|
| Issue date: | 07/05/1985 |
| From: | Heltemes C NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD) |
| To: | Harold Denton, Minogue R, Taylor J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE), Office of Nuclear Reactor Regulation, NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| Shared Package | |
| ML20129H990 | List: |
| References | |
| NUDOCS 8507220107 | |
| Download: ML20129H987 (2) | |
Text
i , f y $ 4 DISTRIBUTION:
) PDR AE00 CF ROAB CF m 0 5 1985 R0AB SF H0rnstein WLanning 11EHORANDUti FOR: Harold R. Denton, Director DZukor Office of Nuclear Reactor Regulation KSeyfrit CHeltemes James li. Taylor, Director TIppolito Office of Inspection and Enforcement Robert B. Hinogue, Director Office of Nuclear Regulatory Research Thomas E. Hurley, Regional Administrator, Region I J. Helson Grace, Regional Administrator, Region II James G. Keppler, Regional Administrator, Region III Robert D. Martin, Regional Administrator, Region IV John B. Martin, Regional Administrator, Region V FR011: C. J. Heltenes, Jr. Director Office for Analysis and Evaluation of Operational Data
SUBJECT:
REQUEST FOR PEER REVIEW COMiiENTS -- PRELIlilNARY CASE STUDY REPORT -- DECAY HEAT REMOVAL PROBLEMS AT U.S. PRESSURIZED WATER REACTORS A preliminary case study on DHR losses at operating PWRs is attached. The study analyzes 130 losses of DHR systems at U.S. PWRs between 1976 and 1983 and notes that for some likely events, a loss of DHR can result in core uncovery within one to three hours.
Our case study report indicates the root causes of the DHR losses, and it examines specific actions that have been thken at several plants to improve the availability of their DHR systens. The report makes six recommenda-
- tions, which if implemented, will significantly reduce the frequency, duration and severity of loss-of-DHR events.
In'accordance with our " peer review" process prior to the finalization and distribution of our case study reports, we are providing NRR, IE, Regional
, Offices, RES, NSAC and INPO with a copy of a preliminary report for review and comment, particularly regarding accuracy and completeness of the technical
) 8507220107 850705 PDR MISC 8507220107 PDR
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W W W 7._2 M 8.m W MwiM_ _" Y E5&. M_ _. _W_"EL M S details. Changes to the findings, conclusions, and recommendations will be considered only if the underlying information concerning the details of plant design or systems operation is in error. Therefore, comments are being solicited on the technical accuracy of the reoort. The findings, conclusions, and recommendations are provided for your information in order that you may understand the significance AE0D places on these events and, therefore, obtain a more complete picture of the total report. We would welcome comments either informally by telephone or formally by memorandum.
~ Since we wish to finalize and issue the report shortly, we ask that any comments be received by us within 30 days from receipt of the preliminary copy. Should your office require some additional time beyond that point, please let us know; otherwise, it will be assumed that there are no comments.
A copy of the preliminary report and this letter are being placed in the Public Document Room at 1717 H Street, N.W., Washington, D.C. 20555.
If you have any questions regarding this study, please feel free to contact Dr. Hal Ornstein at 492-4439.
C. J. Heltemes, Jr., Director Office for Analysis and Evaluation of Operational Data
Enclosure:
As stated cc w/ enclosure:
F. Gillespie, RES/D/DRA0 R. Bernero, NRR/D/DSI T. Speis, NRR/D/ DST J. Knight, NRR/AD/DE W. Russell, NRR/AD/DHFS D. Beckham, NRR/C/0LB V. Stello, ED0/DED/ROGR E. B rech , ED0/DED/ROGR E. Jordan, IE/D/DEPER B. Grimes, IE/0/DQAVT J. Partlow, IE/DINP E. Rossi, IE/C/EAB J. Gagliardo, IE/D/TTC B. Sheron, NRR A. Marchese, NRR F. Rowsome, NRR T. Dunning, NRR T. Marsh, NRR L. Phill'ips, NRR G. Mazetis, NRR
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