ML15223A701
| ML15223A701 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 01/12/1981 |
| From: | Reid R Office of Nuclear Reactor Regulation |
| To: | Parker W DUKE POWER CO. |
| Shared Package | |
| ML15223A703 | List: |
| References | |
| NUDOCS 8101270799 | |
| Download: ML15223A701 (8) | |
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R 1 2.
Docket File NSIC RReid '
NRC PDR ORB#4 Rdg MFairtile L PDR DEisenhut RIngram RPurple AORS-16 Docket No. 50-269 RTedesco OEED GLainas AEOD' TNovak IE-3 Gray File Mr. Wililam 0. Parker, Jr.
Vice President.
Steam Production Duke Power Company P. 0. Box 2178 422 South Church Street Charlotte, North Carolina 282
Dear Mr. Parker:
In order to complete our review of the Cycle 6 re11oad at,the. Ocone'e.
Nuclear Station Unit No. 3 we find6hat we edaddi in mnaton.Note that Questions3nd4,t1cwr annte oy u.
by telecopy to expedite the r~ei~,a~~noitd te oigi nal numbering. scheme is maintan-_._,,,,,._
Kindly respond within 30 dayi qf receiptpf this letter wth. three signed originals and 37 additiq1o
,, ;p1es,.
Sincerely, Robert W. Reid, Chief Operating Reactors Branch #4 Division of Licensing
Enclosure:
1 Request for :Aldditional Information
- 2.
I3&W Letter of September 5
~
1980
- 3.
NRC Letter of October 28, 1980 cc w/qnclosures:
See next page 8211270 OFFICEO QR f4: DL4. C-O.....................
SURNAMEO MFairtile NA
.NRCFOR 31(10/0)NCM040 SGPO 190-39-I OFFIIAL ECOR COP
REGUNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 January 12, 1981 Docket No. 50-269 Mr. William 0. Parker, Jr.
Vice President Steam Production Duke Power Company P. 0. Box 2178 422 South Church Street Charlotte, North Carolina 28242
Dear Mr. Parker:
In order to complete our review of the Cycle 6 reload at the Oconee Nuclear Station Unit No. 3 we find that we need additional infor mation.
Note that Questions 3 and 4, which were transmitted to you by telecopy to expedite the review, have been omitted, but the origi nal numbering scheme is maintained.
Kindly respond within 30 days of receipt of this letter with three signed originals and 37 additional copies.
Sincerely, Robert W. Reid, Chief Operating Reactors Branch #4 Division of Licensing
Enclosure:
.1. Request for Additional Information
- 2. B&W Letter of September 5, 1980
- 3. NRC Letter of October 28, 1980 cc w/enclosures:
See next page
Duke Power Company cc w/enclosure(s):
Mr. William L. Porter Duke Power Company P. 0. Box 2178 422 South Church Street Office of Intergovernmental Relations Charlotte, North Carolina 28242 116 West Jones Street Raleigh, North Carolina 27603 Oconee Public Library 201 South Spring Street Walhalla, South Carolina 29691 Honorable James M. Phinney County Supervisor of Oconee County Walhalla, South Carolina 29621 Director, Criteria and Standards Division Office of Radiation Programs (ANR-460)
U. S. Environmental Protection Agency Washington, D. C. 20460 U. S. Environmental Protection Agency Region IV Office ATTN:
EIS COORDINATOR 345 Courtland Street, N.E.
Atlanta, Georgia 30308 Mr. Francis Jape U.S. Nuclear Regulatory Commission Route 2, Box 610 Seneca, South Carolina 29678 Mr. Robert B. Borsum Babcock & Wilcox Nuclear Power Generation Division Suite 420, 7735 Old Georgetown Road Bethesda, Maryland 20014 Manager, LIS NUS Corporation 2536 Countryside Boulevard Clearwater, Florida 33515 J. Michael McGarry, III, Esq.
DeBevoise & Liberman 1200 17th Street, N.W.
Washington, D. C. 20036 REQUEST FOR ADDITIONAL INFORMATION OCONEE NUCLEAR STATION UNIT 3, CYCLE 6 RELOAD I, References.1 and 2 (attached) discuss the Babcock & Wilcox TAFY and TACO codes as used for fuel and ECCS analyses. We believe that the revised LOCA kW/ft limits given in Ref. 1 apply to the Oconee Nuclear Station Unit 3, Cycle 6 reload. Therefore, (a) verify that the NRC assumptions as given in Ref. 2 are correct and applic able to Oconee 3 for the proposed cycle of operation.
(b) verify that the revised LOCA kW/ft limits as given in Ref. 1 will be used for the proposed cycle of operation and that the Duke December 22, 1980 submittal provides Technical Specification limits to reflect this use.
2.,The Oconee Unit 3, Cycle 6 Reload Report (Ref. 3) describes fuel rod design analyses for cladding collapse (4.2.1), cladding stress (4.2.2), and cladding strain (4.2.3). For each of these sections, identify the analyses presented as:
(a) Bounded by conditions previously analyzed in the Oconee Unit 3 FSAR.
(b)
Analyzed specifically for Cycle 6 conditions using methods and limits pre viously reviewed and approved by the NRC.
(c)
Analyzed specifically for Cycle 6 conditions using generic methods or limits not previously reviewed by the NRC.
Those analyses identified as category (a) or (b) need not be discussed in the reload report. Analyses identified as category (c) should be discussed in suf ficient detail to allow review and approval by the staff prior to restart.
5 On November 9, 1979, a letter (Ref. 5) was issued to all operating light water reactors on the subject of cladding swelling and rupture models used in the ECCS analysis.
Verify that your January 8 1980 response is applicable to Cycle 6 operation AtiOconee
- 3.
6 The initial density (95.0% T.D.) of the Batch 8 fuel is higher than that of the three previous batches (94 T.D.)
used in the Cycle 6 core. Were all changes due to the higher-density fuel, such as those shown in Table 4-2, calculated with the methods described in Ref. 6 and 7?
Were any of the more recent Babcock and Wilcox densifi cation methods, such as Rev. 8, considered in these non-LOCA portions of the Cycle 6 safety analysis?
7 A Babcock and Wilcox report on control rod guide tube wear (Ref. 9) is currently under review by the staff.
Is this report applicable to Oconee Unit 3 Cycle 6? Do you concur with the findings of this report?
8 Section 6 of the reload report describes a rod bow DNBR penalty calculated specifically for Cycle 6 operation.
(a) Please provide the details of this calculation.
Specifically, what were the values of:
K, a(Ac/cl F(k/a), f(k/o), U, an,
a6 6,
N 1,
a
, Nb 1 and DNBRs o
(b) What is the magnitude of credit taken for the flow-area reduction hot channel factor?
(c) Are the margins used to offset the rod bowing DNBR penalty employed solely for this purpose?
If not, please provide justification for using these margins more than once.
(d) Amend the basis of the technical specifications to identify each generic or plant-specific margin that has been used to offset the reduction in DNBR due to rod bowing. Also, reference either the source or approval of each generic margin.
REFERENCES
- 1. J. H. Taylor (B&W) letter to L. S. Rubenstein (NRC) dated September 5.,
1980.
- 2. L.
S. Rubenstein (NRC) letter to J. H. Taylor (B&W) dated October 28, 1980.
- 3.
Oconee Unit 3, Cycle 6 Reload Report, Babcock and Wilcox Company Report BAW-1634, August 1980.
.z.
(lorida Power CorDoration) letter to C. Nelson (NRC) on "Crytl 7
7iver Unit 3 Status Report -
May 1, 1978," dated
- 5. D. G. Eisenhut (NRC) letter to all Operating Light Water Reactors dated November 9, 1979.
- 6. C. D. Morgan and H. S. Kao, TAFY -
FUEL PIN TEMPERATURE AND GAS PRESSTURE ANALYSIS, Babcock and Wilcox Company Report BAW-10044, May 1972.
- 7. OCONEE 3 FUEL DENSIFICATION REPORT, Babcock and Wilcox Company Report BAW-1399, November 1973.
- 8. B. J. Buescher and J. W. Pegram, BABCOCK AND WILCOX MODEL FOR PREDICTING IN-REACTOR DENSIFICATION, Babcock and Wilcox Company Report BAW-10083P-A Revision 1, July 1977.
- 9. CONTROL ROD GUIDE TUBE WEAR MEASUREMENT PROGRAM, Babcock and Wilcox Company Report BAW-1623, June 1980.
Babcock &Wilcox Power Generation Group P.O. Box 1260, Lynchburg, Va. 24505 Telephcne: (804) 384-5111 September 5, 1980 Mr. Lester S. Rubenstein Assistant Director for Reactor Systems Division of System Integration Office of Vuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C.
20555
Dear Mr. Rubenstein:
This letter will document the phone conversation between our John Willse and your Bill Johnston (et. al.) on the afternoon of September 4, 1980 on the plan to resolve concerns over the use of B&W's TAFY code for fuel and ECCS analyses.
BACKGROUND B&W was in the process of doing a precise analytical evaluation of the conservatism's which exist in the ECCS analysis with TAFY inputs, when, on July 3, 1980 we received a call from Les Rubenstein to report that the NRC did not have adequate staff to accomplish a near term review of B&W's analytical evaluation.
Mr. Rubenstein stated that B&W should plan on an appropriate reduction of the LOCA kw/ft limits to account for mechanistic fuel densification, until a switch to a TACO-type model could be made.
(TACO incorporates a mechanistic fuel densification model).
B&W replied that this direction would be discussed with B&W plant owners, and the results of that discussion re ported to the NRC. A meeting with B&W owners was held late in July, and an action plan to respond to the NRC's direction was developed over the next several weeks.
This plan was presented to the NRC in the September 4th phone call.
SEPTEMBER 4TH PHONE CALL The action plan presented by B&W during,this phone call has two major elements:
- 1. Complete transition from TAFY to TACO2-for fuel and ECCS analyses.
TACO2 is an advanced version of the TACO code with a very accurate treatment of end-of-life fission gas release. TACO2 has o
been submitted but has 'not yet been reviewed,by the NRC.
NRC review would have to be expedited to support this transition.
Wac~
.-cox Comc.any Estabisnec 1867
Page 2 9/5/80
- 2. Until transition to TACO2 can be effected, the cur rent LOCA kw/ft limits will be appropriately reduced for approximately the first 50:EFPD's of the cycle life to account for mechanistic fuel densification.
The current and revised LOCA limits are given below:
B&W 177 F.A. LOWERED LOOP PLANTS (BAW-10103)
Core Elevation Present Revised (ft.)
Limit (kw/ft)
Limit (kw/ft) 2 15.5 14.5 4
16.6 16.1 6
18.0 17.5 8
17.0 17.0 10 16.0 16.0 B&W 177 F.A.
RAISED LOOP PLANTS (BAW-10105) 2 16.5 16.0 4
17.2 16.8 6
18.4 18.0 8
17.5 17.5 10 17.0 17.0 NRC agreed to this plan and indicated that, barring major techni cal difficulties with the code, they should be able to complete their review and approve TACO2 by March, 1981.
Upon approval, B&W would perform a reanalysis of the LOCA limits for the operating plants with TACO2 inputs.
Thereafter, TAFY would be discontinued from further use.
Please confirm our understanding of the September 4 phone call and the action plan stated herein.
Very truly yours, T
BABCOCK & WILCOX CO.
J. H. TAYLOR, Manager, Licensing JHT:dr cc:
R. B.
Borsum (B&W)
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