ML15260A226
| ML15260A226 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 09/06/1991 |
| From: | Wiens L Office of Nuclear Reactor Regulation |
| To: | Tuckman M DUKE POWER CO. |
| Shared Package | |
| ML15260A227 | List: |
| References | |
| IEB-88-011, IEB-88-11, TAC-72148, TAC-72149, TAC-72150, NUDOCS 9109130119 | |
| Download: ML15260A226 (3) | |
Text
September 6, 1991 Docket Nos. 50-269, 50-270 DISTRIBUTION:
OGC, 15B18 and 50-287 Docket File ACRS (10)
NRC & Local PDRs LReyes, RH PDII-3 R/F JShea, 3H5 Mr. M. S. Tuckman, Vice President Oconee R/F SHou, 7E23 Nuclear Operations SVarga JNorberg, 7D2 Duke Power Company GLainas P. 0. Box 1007 DMatthews Charlotte, North Carolina 28201-1007 LWiens LBerry
Dear Mr. Tuckman:
Edordan, MNBB3701
SUBJECT:
PRESSURIZER SURGE LINE THERMAL STRATIFICATION, BULLETIN 88-11, OCONEE UNITS 1, 2, AND 3 (TAC NOS. 72148, 72149, AND 72150)
The NRC staff and its consultant, Brookhaven National Laboratory, have completed their review of the Babcock and Wilcox Owners Group (BWOG) report (BAW-2127) on generic final analysis of surge line thermal stratification. The staff concluded that the methodology used to evaluate and analyze the stress and fatigue effects due to thermal stratification and thermal striping was generally acceptable. NRC staff concerns and questions on the report were resolved and found to be acceptable with the exception of one major issue.
This issue involves the stress index used in calculating thermal expansion stress for surge line elbows. This issue may have significant impact on acceptability of stress levels and fatigue life of the surge line and hence, needs to be resolved expeditiously. The NRC staff has suggested several options for resolving this issue in the enclosed Safety Evaluation. The NRC staff will review the proposed resolutions when they are received.
In letters dated January 30 and June 28, 1991, you provided verification of the.plant specific applicability of the B&WOG program and results. This included a verification of the analysis assumptions, qualifications of supports and attached piping and revision of operating procedures as indicated in BAW-2127. However, pending resolution of the remaining issue identified above, this activity will remain open. If a revision to BAW-2127 is necessary, you are requested to provide verification, in writing, of the applicability of the revised program and results to Oconee Units, 1, 2, and 3.
This requirement affects four respondents, and, therefore, is not subject to Office of Management and Budget review under P.L.96-511.
Sincerely,
/s!
919319900 Leonard A. Wiens, Project Manager 9109130119 910906 PoetDrcoaeI PDR ADOCK 05000269 PDR
_Division of Reactor Projects -
I/II Office of Nuclear Reactor Regulation
Enclosure:
Safety Evaluation cc w/enclosure:
See next p ge OFC LA:PDI PM. DII-3 NAME LBery LWiens:cw ews
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/9 OFFICIAL RECORD COPY Document Name:
LTR TO DUKE/BULL 88/11 NB FU C E
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0 UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555 September 6, 1991 Docket Nos. 50-269, 50-270 and 50-287 Mr. M. S. Tuckman, Vice President Nuclear Operations Duke Power Company P. 0. Box 1007 Charlotte, North Carolina 28201-1007
Dear Mr. Tuckman:
SUBJECT:
PRESSURIZER SURGE LINE THERMAL STRATIFICATION, BULLETIN 88-11, OCONEE UNITS 1, 2, AND 3 (TAC NOS. 72148, 72149, AND 72150)
The NRC staff and its consultant, Brookhaven National Laboratory, have completed their review of the Babcock and Wilcox Owners Group (BWOG) report (BAW-2127) on generic final analysis of surge line thermal stratification. The staff concluded that the methodology used to evaluate and analyze the stress and fatigue effects due to thermal stratification and thermal striping was generally acceptable. NRC staff concerns and questions on the report were resolved and found to be acceptable with the exception of one major issue.
This issue involves the stress index used in calculating thermal expansion stress for surge line elbows. This issue may have significant impact on acceptability of stress levels and fatigue life of the surge line and hence, needs to be resolved expeditiously. The NRC staff has suggested several options for resolving this issue in the enclosed Safety Evaluation. The NRC staff will review the proposed resolutions when they are received.
In letters dated January 30 and June 28, 1991, you provided verification of the plant specific applicability of the B&WOG program and results. This included a verification of the analysis assumptions, qualifications of supports and attached piping and revision of operating procedures as indicated in BAW-2127. However, pending resolution of the remaining issue identified above, this activity will remain open. If a revision to BAW-2127 is necessary, you are requested to provide verification, in writing, of the applicability of the revised program and results to Oconee Units, 1, 2, and 3.
This requirement affects four respondents, and, therefore, is not subject to Office of Management and Budget review under P.L.96-511.
Sincerely, Leonard A. Wiens, Project Manager Project Directorate 11-3 Division of Reactor Projects - I/1I Office of Nuclear Reactor Regulation
Enclosure:
Safety Evaluation cc w/enclosure:
See next page
Mr. M.S. Tuckman Oconee Nuclear Station Duke Power Company Units Nos. 1, 2 and 3 cc:
Mr. A.V. Carr, Esq.
Mr. Stephen Benesole Duke Power Company Duke Power Company 422 South Church Street Post Office Box 1007 Charlotte, North Carolina 28242-0001 Charlotte, North Carolina 28201-1007 J. Michael McGarry, III, Esq.
Winston and Strawn Mr. Alan R. Herdt, Chief 1400 L Street, N.W.
Project Branch #3 Washington, D.C. 20005 U.S. Nuclear Regulatory Commission 101 Marietta Street, NW, Suite 2900 Mr. Robert B. Borsum Atlanta, Georgia 30323 Babcock & Wilcox Nuclear Power Division Ms. Karen E. Long Suite 525 Assistant Attorney General 1700 Rockville Pike N. C. Department of Justice Rockville, Maryland 20852 P.O. Box 629 Raleigh, North Carolina 27602 Manager, LIS NUS Corporation Mr. R.L. Gill, Jr.
2650 McCormick Drive, 3 Floor Nuclear Production Department Clearwater, Florida 34619-1035 Duke Power Company P.O. Box 1007 Senior Resident Inspector Charlotte, North Carolina 28201-1007 U.S. Nuclear Regulatory Commission Route 2, Box 610 Seneca, South Carolina 29678 Regional Administrator, Region II U.S. Nuclear Regulatory Commission 101 Marietta Street, N.W., Suite 2900 Atlanta, Georgia 30323 Mr. Heyward G. Shealy, Chief Bureau of Radiological Health South Carolina Department of Health and Environmental Control 2600 Bull Street Columbia, South Carolina 29201 Office of Intergovernmental Relations 116 West Jones Street Raleigh, North Carolina 27603 County Supervisor of Oconee County Walhalla, South Carolina 29621