ML20070L680
| ML20070L680 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 12/14/1982 |
| From: | Root R WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | Sternberg D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, G1-82-805, GO1-82-0805, GO1-82-805, NUDOCS 8301030262 | |
| Download: ML20070L680 (2) | |
Text
Docket No. 50-460
..g 50.55(o) Report g
C Washington Public Power Supply System
($08)g2 P.O. Box 968 3000GeorgeWashingtonWay Richland, Washington 99352 000 Docket Number 50-460
'2/
December 14, 1982 Responds to: -
EEsg4 '!6:7 G01-82-0805 Response required by: NA Nuclear Regulatory Commission Region V 1450 Maria Lane, Suite 120 Walnut Creek, California 94596 Attention: Mr. D. M. Sternberg, Chief Reactor Projects Branch No. 1
Subject:
NUCLEAR PROJECT NO. I 10CFR50.55(e) POTENTIALLY REPORTABLE CONDITION REACTOR VESSEL FLANGE STUD HOLES
Reference:
Telecon, C.R. Edwards, Supply System to A. D'Angelo, Region V, Nuclear Regulatory Commission, 11/15/82 In the above reference, the Supply System informed your office of a potentially reportable deficiency in accordance with the requirements of 10CFR50.55(e).
Attachment A includes a brief description of the identified potential deficiency and the Project's planned corrective action.
Due to the extented construction delay of the WNP-1 Project, implementation of any corrective actions will not occur until restart of construction.
In the interim, when the noted deficiencies have been dispositioned, we will provide your office with a status report.
If you have any estions or desire further information, please advise.
R. W. Root, Acting Assistant Program Director RWR:RL:pp cc: JP Laspa, Bechtel (861)
V Mani, UE&C (897)
V Stello, Director of Inspection, NRC A Toth, NRC (917Q)
FDCC (899)
CRM (847) iEM 8301030262 821214 DR ADOCK 05000
=
.J.re ATTACHMENT A WNP-4 P0TENTIALLY REPORTABLE CONDITION PER 10CFR50.55(e)
REACTOR VESSEL FLANGE STUD H0LE - STUCK STUD
Background
An alignment / handling stud used on the WNP-4 reactor vessel flange during handling operations was declared stuck when it became diffi-cult to remove. Subsequent destructive removal of the stud revealed discontinuities of the thread form in the vessel flange and led to the issuance of Nonconformance Report 4-BNCR-04-03.
Description of Deficiency The deficiency can be described as the absence of several single thread forms of varying lengths. The longest length of missing thread can be characterized as approximately one half of the stud hole circumference and the total length of missing threads is equi-valent to approximately three circumferences.
Safety Implication The reactor vessel flange stud hole threads form a part of the mechan-ical interface for locking the reactor closure head to the reactor vessel. Discrepancies in the stud hole thread form could possibly affect the design requirements for maintaining the integrity of the primary reactor coolant pressure boundry. However, to date it is indeterminant as to whether the design requirements have been affected.
Corrective Action The deficiency has been documented via the above mentioned BHCR, and a technical evaluation will be performed by the vessel manufac-turer (B&W) and by the Engineer (United Engineers & Constructors).
This evaluation is expected to be completed during the first quarter of 1983. The Project will continue to track this as an open item during the extended construction delay and will provide you with a final report when a decision of final corrective action, if required, is reached.
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