ML20248C484
| ML20248C484 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 07/31/1989 |
| From: | Hukill H GENERAL PUBLIC UTILITIES CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| C311-89-2086, IEB-88-008, IEB-88-8, NUDOCS 8908100039 | |
| Download: ML20248C484 (2) | |
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GPU Nuclear Corporation Nggig7 Post Office Box 480 Route 441 South Middletown, Pennsylvania 17057 0191 717 944 7621 TELEX 84-2386 Writer's Direct Dial Number:
July 31,1989
'C311-89-2086 U. 5. Nuclear Regulatory Commicsion Attn:
Document Control Desk Washington, DC 20555 Deer Sir:
Three Mile Island Nuclear Station, Unit 1 (TMI-1) 1 Operating License No. DPR-50 Docket No. 50-289 GPUN Response to NRC Bulletin 88-08
" Thermal Stresses in Piping Connected to Reactor Coolant Systemd' Revised Schedule for Responding to Action Item 3 The purpose of this letter is to revise our schedule for i
completing our response to NRC Bulletin 88-08 consistent with the schedule given in the bulletin.
In accordance with the. bulletin, Actions 2 and 3 are required to be completed before the end of the Cycle 8 Refueling (8R) Outage (currently scheduled to begin on January 5, 1990), and to provide a report on the actions taken within 30 days of completing Actions 2 and'3.
(
GPUN's letter dated October 21, 1988 (C311-88-2145) provided a i
response to Action Items 1 and 2 of Bulletin 88-08 (including its 1
Supplements 1 and 2).
In our letter, we stated that the Makeup
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and Purification - High Pressure Injection (HP1) System has a i
configuration similar to the system described in the bulletin.
]
Unisolable sections of HPI piping connected to the RCS could be impacted by potential globe valve leakage from upstream since the pressure at the inlet of the valve exceeds RCS pressure.
Our letter gave the results of non-destructive examinations (NDE) where no indications were observed usin'g the enhanced techniques and stated that we were evaluating the HPI System piping for potentially being subjected to unanticipated cyclic thermal stresses sufficient to cause fatigue failure in completion of Action Item 3.
We further stated that the results would-be reported to the NRC by July, 1989.
We based this schedule on the need to identify any required BR modifications ahead of the outage.
i 8909100039 890731 N
PDP ADOCK 050002892 lh G
PNU GPU Nuclear Corporation is a subsidiary of the General Public Utilities Co t
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, s-Q11-89-2086 July 31,1989 Currently we have performed analysis which demonstrates that under constant leakrate conditions 2 0.1 gpm, stratified conditions in non-isolable portions of HPI piping, as discussed in NRC Bulletin 88-08, will not develop.
As a result of our evaluation to date, we believe that modifications will not be needed.
However, before completing our evaluation, we feel that additional work is needed to obtain further insights in confirmation of the conclusions.
We will inform the NRC by the end of August of any additional action that may be needed or provide the results of our evaluation if complete at that time.
Sincerely, M
b H. D.
ill Vice President and Director, TMI-1 HDH/MRK cc; J.-Stolz R. Hernan F. Young W., Russell i
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