ML20244D646
| ML20244D646 | |
| Person / Time | |
|---|---|
| Site: | Farley  |
| Issue date: | 06/12/1989 |
| From: | Hairston W ALABAMA POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-89-001, IEB-89-1, NUDOCS 8906190175 | |
| Download: ML20244D646 (7) | |
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A!abama Power Company e 600 North 18th Street Post Office Dox 2641 Dirmingharn, Alabama 352914400 l
Telephone 205 250-1837 l
W.G Hairston,lll Senior Vice PresKient Nuclear Operations Alabama Power the sourhem ewn meern 10CFR50.54(f)
June 12, 1989 Docket Nos. 50-348 50-364 U. S. Nuclear Regulatory Commission Attention:
Document Control Desk Vashington, D. C.
20555 Gentlemen:
Joseph H. Farley Nuclear Plant - Units 1 & 2 Response to NRC Compliance Bulletin 89-01 In response to NRC Compliance Bulletin 89-01, " Failure of Westinghouse Steam Generator Tube Mechanical Plugs," the following information is provided for the actions requested:
1.
NRC Item Addressees ere requested to verify that information contained in References 1 and 2 relating specifically to their plants is correct for plugs supplied froru heat numbers 3279, 3513, 3962, and 4523. The specific information to be verified is the number of Westinghouse mechanical plugs installed in the hot and cold legs broken down by steam generator number, heat number, and date of installation.
If information from these references is incorrect, appropriate corrections should be identified.
Addressees are requested to so state if their plants have not installed Westinghouse mechanical plugs from the subject heats.
APCo Response The information contained in. References 1 and 2 relating specifically to Farley Nuclear Plant Units 1 (ALA) and 2 (APR) is correct except for the following:
There are 41 plugs of heat no. 3962 in APR S/G "" HL which were ihstalled in April 1986.
Reference 1, VCAP-12:td Revision 1, has 42 plugs listed; however, 1 plug was replaced,
April 1989 with a plug from heat no. 6135.
There are 56 plugs of heat no. 4523 in APR S/G "C" HL which were installed in October 1987. Reference 2, Westinghouse letter to NRC dated May 1, 1989 (NS-NRC-89-3432) " Steam Generator Tube Plug Integrity Update," has 61 plugs listed; however, 5 plugs were replaced April 1989 with plugs from heat no. 6135.
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8906190175 890612 PDR ALOCK 05000348 Q
PDC l
I 1
U. S. Nuclear Regulatory Commission Page 2 2.
NRC Item Addressees are requested to take the following actions, to be implemented initially during any refueling outage or extended outage (greater than four weeks) which ends 30 days or more following receipt of this bulletin and during all future refueling outages.
NRC Item 2a Steam generator tube plug lifetime for plugs from heats 3279, 3513, 3962, and 4523 should be estimated using the methodology from References 1 and 2 and should be based on the Millstone Unit 2 benchmark subject to any corrections per item 1 above.
Lifetime estimates in Reference 2 for plugs fabricated from heat 4523 are based on the Farley Unit 2 benchmark. These estimates should be adjusted to l
reflect the Millatune Unit 2 benchmark using the methodology described in Section 4.1.2 of Reference 1.
APCo Response Adjusted lifetime estimates refleet.1g the Millstone Unit 2 benchmark using the methodology described in Section 4.1.2 of Reference 1 are shown in Tables I and II (attached) for the Parley plugs fabricated from heats 3962 and 4523. As noted in these tables, the Unit 2 hot leg plugs were modified during the sixth refueling outage (April 1989) using the Plug in a Plug (PIP) method of repair.
PIP is a repair method designed to prevent signiffi. ant tube damage thus eliminating the necessity for future lifetime calculations for these particular plugs.
NRC Item 2b Addressees should implement appropriate remedial actions (i.e., repair and/or replacement) for all plugs whose estimated lifetimes in 2a above do not extend to the next refueling outage.
If operation is planned beyond a refueling outage that represents the le.st outage before any plug exhausts the predicted lifetime, an alternative schedule with the appropriate technical justification should be submitted to the NRC at least 30 days before the end of this refueling outage.
APCo Response The Unit I hot leg plugs fabricated from heats 3962 and 4523 vill have negative estimated lifetimes prior to the next regularly scheduled refueling outage (see Tables I and II). Therefore, in accordance with Section 4.1.1.2 of Reference 1, the hot leg plugs vill be repaired and/or replaced during the Unit I ninth refueling outage tentatively scheduled to begin in September 1989.
The estimated life for the remaining cold leg plugs in Unit 1 fabricated from these heats will be reassessed each refueling outage using the methodology and data contained in this response. Based on each assessment, plugs which have negative estimated lifetimes prior i
to the following refueling outage vill be repaired and/or replaced at that time.
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B m.i a-p E
jj LU. S. Nuclear Regulatory Commission:
Page'3 As discussed in the response.to Item 1, six plugs of the affected heats in Unit 2 have been replaced. The' remaining Unit 2 hot legL plugs fabricated from heats 3962 and 4523 vere all modified utilizing i
PIP as discussed in the response to Item 2a.
The Unit 2 cold leg j
plugs fabricated from these heats vill have lifetime estimates i
reassessed each refueling outage and repairs and/or replacements vill be made prior to any plugs reacting a. negative lifetime estimate.
L NRC Item 2c.
. Prior to'any plug repairs or replacement, addressees are' reminded that their responsibilities under ALARA require analysis of the various plug repair or replacement methods available to determine which method vill result in the lowest overall personnel radiation-exposure while still remaining cost-effective.
In choosing a plug repair or
. replacement method, the licensee should consider the accessibility of the plugs and the dose reduction benefit of using robotic manipulators.
Prior to plug repair or replacement, the licer.see i
should consider steam generator decontamination and/or local shielding to reduce working area dose rates.
APCo Response Radiation exposure,.robotic manipulators, accessibility, shielding,
' decontamination, and schedule were considered in the actions completed and vill be addressed in detail for future individual'and overall operations.
NRC Item 2d Installation of Westinghouse mechanical plugs from heats 3279, 3513,.
3962, and 4523 should 5e discontinued.
APCo Response Alabama Power Company will not install plugs from heats 3279, 3513, 3962 and 4523.
NRC Iten 2e Westinghouse mechanical plugs removed from steam generators, regardless of heat number, should be examined for PVSCC on a sample basis for each heat.
Addressees should maintain a record of these examinations and the results should be provided to Westinghouse to improve the database concerning the susceptibility of plugs to PWSCC.
APCo Response Samples of heats 3962 and 4523 from APR S/G "C" HL vere examined by Westinghouse this April and the results have been included in the database. As additional plugs are removed evaluations will be performed and Westinghouse vill be advised of the results.
U. S. Nuclear Regulatory Commission Page 4 3.
NRC Item L
Remedial actions at plants where the steam generator tubes are partially-depth-expanded within the tubesheet as described above may be deferred on a one-time basis to the next scheduled refueling outage if the outage that immediately follows receipt of this bulletin ends before October 1, 1989.
APCo Response
~FNP steam generator tubes are not partial depth expanded (length of tube expansion within the tubesheet is less than 3 inches).
Unit 1 tubes were expanded the full length using the Vestex process and the Unit 2 tubes ve.re liard rolled the full length.
4.
NRC Item Remedial actions for " sentinel related" mechanical plugs described above may be deferred on a one-time basis to the next refueling outage if the outage that immediately follows receipt of this bulletin ends before October 1, 1989.
APCo Response
" Sentinel related" plugs have not been installed in the Farley Nuclear Plant steam generators.
If there are any questions, please advise.
Respectfully submitted, ALABAMA POWER COMPANY th N
V. G. Hairston, III VGH/ CDP:cht-8.45 Attachments cc:
Mr. S. D. Ebneter Mr. E. A. Reeves Mr. G. F. Maxwell SVORN TO AND SUBSCRIBED BEFORE HE TH1S 12[ DAY OF O u w, 1989
/
O a : // k c L (O Ngttary Public S
My Commission Expires:
EXPlREscIc I5.199
e bc:
Mr. R. P. Mcdonald Mr. Bill H. Guthrie Mr. J. D. Voodard.
Mr. J. W. McGovan Mr. D. N. Morey Mr. C. D. Nesbitt Mr. Scott Fulmer Mr. D. E. Hansfield Mr. K. V. McCracken C.naitment Tracking System (2)
File:
B-21.1.7 A-5001, NRCB 89-01 l
8 l
l l
TABLE I FARLEY NUCLEAR PLANT MECHANICAL PLUG DATA - HEAT NO. 3962
'STD HL Remaining EFPD PLT INST
- OF SG or or To Min. Lig.
ALPHA DATE PLUG CL From 5/1/89 REMARKS l
ALA 10-86 4
A HL
-310.7 ALA 10-86 2
C HL
-310.7 ALA 10-86 4
A CL 3149.9 ALA 10-86 2
C CL 3149.9 APR 4-86 11 A
HL Repaired
- APR 4-86 15 B
HL Repaired
- APR 4-86 41 C
HL Repaired
- APR 4-86 11 A
CL 3088.2-APR 4-86 15 3
CL 3088.2 APR 4-86 44 C
CL 3088.2
- Repaired using Plug in a Plug (PIP) in April 1989.
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TABLE II FARLEY NUCLEAR PLANT MECHANICAL PLUG DATA - HEAT NO. 4523 STD HL Remaining EFFD PLT INST
- OF SG or To Hin. Lig.
l ALPHA DATE PLUG CL From 5/1/89 REMARKS ALA 4-88 4
A HL 132.6 ALA 4-88 1
B HL 132.6 ALA 4-88 12 C
HL 132.6 ALA 4-88 4
A CL 3593.2 ALA 4-88 1
B CL 3593.2
'ALA 4-88 12 C
CL 3593.2 APR 10-87 13 A
HL Repaired
- APR 10-87 35 B
HL Repaired
- APR 10-87 56 C
HL Repaired
- APR 10-87 13 A
CL 3545.9 APR 10-87 35 B
CL 3545.9 APR 10-87 61 C
CL 3545.9
- Repaired using Plug in.a Plug (PIP) in A,.ril 1989.
/cht:8.47
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