ML16152A761
| ML16152A761 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 12/05/1988 |
| From: | Matthews D Office of Nuclear Reactor Regulation |
| To: | Tucker H DUKE POWER CO. |
| References | |
| TAC-65759, TAC-65760, TAC-65761, NUDOCS 8812080027 | |
| Download: ML16152A761 (4) | |
Text
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UNITED STATES oll NUCEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 December 5, 1988 Docket Nos.:
50-269, 50-270 and 50-287 Mr. H. B. Tucker, Vice President Nuclear Production Department Duke Power Company 422 South Church Street Charlotte, North Carolina 28242
Dear Mr. Tucker:
SUBJECT:
CAVITY DOSIMETRY PROGRAM - OCONEE NUCLEAR STATION UNITS 1, 2, AND 3 (TACS 65759, 65760, and 65761)
Your letter dated September 8, 1986, requested NRC concurrence on your understanding that Appendix H, "Reactor Vessel Material Surveillance Program Requirements" of 10 CFR Part 50 does not require a separate cavity dosimetry installation for each Oconee unit.
The principal objectives of the integrated reactor vessel material surveillance program (IRVSP) are to determine the changes in the mechanical properties of the reactor vessel resulting from long-term, neutron irradiation and to monitor the neutron fluence as required by 10 CFR Part 50, Appendix G, "Fracture Toughness Requirements" and Appendix H. For Oconee, the main objectives of the IRVSP will be satisfied when the last surveillance capsules for Units 2 and 3 and Unit 1 are removed from the host Crystal River-3 reactor at the end of the sixth and seventh cycles, respectively. At that time, the Oconee reactor vessel surveillance capsule program will be completed since the surveillance specimens will have accumulated a neutron fluence equal to that at the end of reactor vessel life.
The approved BAW-1875A, "The Babcock and Wilcox (B&W) Owners Group Cavity Dosimetry Program" outlines a program for benchmarking and developing a cavity dosimetry method which will be able to correlate reactor cavity fast flux measurements with the pressure vessel neutron flux. The method will provide the means for an extension of the current Oconee surveillance program and continuous long-term measurements of the vessel fluence.
S4_2(y SU27 88T205 PDR ADOCK 05000269 P
Mr. H. B. Tucker
-2 A plant specific cavity dosimetry program for Oconee will be developed when the results of the BWOG benchmarking become available in the early 1990s.
However, in preparation for the Oconee cavity dosimetry program, Duke Power Company is planning to install cavity dosimetry hardware only in Oconee Unit 2 during a future refueling outage. The early installation will assure continuous monitoring of the vessel fluence following the withdrawal of the last Oconee capsule. In addition, it will provide sufficient time for debugging and possibly benchmarking of the cavity dosimetry data against the present data from the capsule's program.
Duke Power Company's proposed approach for a dosimetry program does not include installation of cavity dosimetry in Oconee Units 1 and 3. However, fluences for all Oconee units will be determined based on cavity dosimetry data from Unit 2 using the current approved methodologies and semi-emperical methods to be developed by the BWOG program. The vessel fluences for Units 1 and 3 can be determined with some uncertainties based on Unit 2 cavity dosimetry data. Design similarities, operating history, fuel cycle designs and some operation personnel are similar for all three units.
You state that a cavity dosimetry program based on data from Unit 2 cavity dosimetry will adequately satisfy the requirements of Appendix H for all Oconee units. The design and operating features of Oconee units are sufficiently similar to allow accurate prediction of fluence and radiation damage as a function of power output for Units 1 and 3 utilizing cavity dosimetry data from Unit 2.
The staff has reviewed your letter and agrees that for a cavity dosimetry program for each reactor, a separate cavity dosimetry installation for each Oconee unit is not warranted. Further, the staff agrees that a dosimetry program for each Oconee reactor consisting of analytical and semi-emperical methods applied to the Oconee Unit 2 cavity dosimetry data can accurately predict the vessel fluences in compliance with the regulatory requirements.
Sincerely, Original Signed By:
David B. Matthews, Project Director Project Directorate 11-3 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation cc:
See next page DISTRIBUTION:
DoketFle-M. Rood 14-H-25 NRC PDR H. Pastis 14-H-25 Local PDR OGC (For inform. Only) 15-B-18 PDII-3 Reading E. Jordan MNBB-3302 S. Varga 14-E-4 B. Grimes 9-A-2 G. Lainas 14-H-3 ACRS (10)
P-315 D. Matthews 14-H-25 Oconee Plant File CYCheng 9-H-15 PD PDII-3*
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- See previous concurrence Mocod' HPastis:ls CYCheng atthews 11/21/88 11/21/88 11/23/88 11/4 /88
Mr. H. B. Tucker
-2 A plant specific cavity dosimetry program for Oconee will be developed when the results of the BWOG benchmarking become available-in the early 1990s.
However, in preparatio for the Oconee cavity dosimetry pr gram, Duke Power Company is planning to install cavity dosimetry hardware only in Oconee Unit 2 during a future refueli outage. The early installaton will assure continuous monitoring of the vessel fluence followin the withdrawal of the last Oconee capsule. In ddition, it will provide ficient time for debugging and possibly ben marking of the cavity simetry data against the present data from the capsu 's program.
Duke Power Company's proposed pproach for a d simetry program does not include installation of cavity osimetry in 0 onee Units 1 and 3. However, fluences for all Oconee units wi 1 be deter ned based on cavity dosimetry data from Unit 2 using the curren approve,,methodologies and semi-emperical methods to be developed by the BWO progr n. The vessel fluences for Units 1 and 3 can be determined with some u cert
'nties based on Unit 2 cavity dosimetry data. Design similarities, o rating history, fuel cycle designs and some operation personnel are simi '
for all three units.
You state that a cavity dosimetry pr gra based on data from Unit 2cavity dosimetry will adequately satisfy /t req irements of Appendix H for all Oconee units. The design and oper ting fe tures of Oconee units are sufficiently similar to allow ac irate pred ction of fluence and radiation damage as a function of power o tput for Uni 1 and 3 utilizing cavity dosimetry data from Unit 2.
The staff has reviewed your,etter and agrees th t for a cavity dosimetry program for each reactor,
,§eparate cavity dosim try installation for each Oconee unit is not warrant d. However, a dosimetr program for each Oconee reactor consisting of anaytical and semi-emperical ethods applied to the Oconee Unit 2 cavity dos metry data can accurately pr dict the vessel fluences in compliance with the eAgulatory requirements.
/
Sincerely,
/
David B. Matthews, Project Director
/
Project Directorate 11-3 Division of Reactor Projects - I/Il Office of Nuclear Reactor Regulation cc:
See next
- ge DISTRIBUTION ocet Fie M. Rood 14-H-25 NRC PDR H. Pastis 14-H-25 Local PDR OGC (For inform. Only) 15-B-18 PDII-3 Reading E. Jordan MNBB-3302 S. Vargal 14-E-4 B. Grimes 9-A-2 G. Lainds 14-H-3 ACRS (10)
P-315 D. Matthews 14-H-25 Oconee Plant File CYCheng 9-H-15 PD P
EJ, PDII-3 Mood H
is:ls CYCng DMatthews 11/1 /88 1 /, /88 11 88 11/ /88
Mr. H. B. Tucker Oconee Nuclear Station Duke Power Company Units Nos. 1, 2 and 3 cc:
Mr. A. V. Carr, Esq.
Mr. Paul Guill Duke Power Company Duke Power Company P. 0. Box 33189 Post Office Box 33189 422 South Church Street 422 South Church Street Charlotte, North Carolina 28242 Charlotte, North Carolina 28242 J. Michael McGarry, III, Esq.
Bishop, Liberman, Cook, Purcell & Reynolds 1200 Seventeenth Street, N.W.
Washington, D.C. 20036 Mr. Robert B. Borsum Babcock & Wilcox Nuclear Power Generation Division Suite 525 1700 Rockville Pike Rockville, Maryland 20852 Manager, LIS NUS Corporation 2536 Countryside Boulevard Clearwater, Florida 33515 Senior Resident Inspector 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 Honorable James M. Phinney County Supervisor of Oconee County Walhalla, South Carolina 29621