ML20214T833
| ML20214T833 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 11/26/1986 |
| From: | Corbin McNeil Public Service Enterprise Group |
| To: | Kane W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| NLR-N86179, NUDOCS 8612090025 | |
| Download: ML20214T833 (3) | |
Text
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Pubhc Service Electric and Gas Cornpany Corbin A. McNeill, Jr.
Public Service Electric and Gas Company P.O. Box 236.Hancocks Bridge, NJ 08038 609 339-4800 Vice President -
Ruclear November 26, 1986 NLR-N86179 United States Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, PA 1940 6 Attention:
Mr. W.
F.
Kane, Director Division of Reactor Projects Gentlemen:
AUGUST 26, 1986 REACTOR TRIP AND FALSE BLACKOUT SIGNAL AT SALEM UNIT NO. 2; STATUS OF CORRECTIVE ACTIONS SALEM GENERATING STATION UNIT NOS. 1 AND 2 DOCKET NOS. 50 -272 AND 50-311 This letter forwards the third monthly status report for the corrective actions taken as a result of the reactor trip and false blackout signal which occurred August 26, 1986 at Salem Generating Station Unit No. 2.
In our status report dated October 31, 1986 we identified the completion of the Salem Station electrical distribution transient analysis by Power Technology Inc. (PTI) and the preparation of a long term plan by Public Service Electric and Gas Company (PSE&G) as the outstanding items to be completed.
Target dates of November 15 and December 15, 1986 respectively, were established for completion of these items.
However, as a result of the resources required to support the Salem Unit 2 refueling outage, these items are now expected to be complete by December 15, 1986 and January 15, 1986 respectively.
On November 18, 1986 at a meeting in your offices, PSE&G proposed to revise its commitments relative to the operation of the Salem Station electrical distribution system.
Presently, in accordance with our previous commitments, all Station electrical loads are being supplied by the station power transformers.
Additionally, Station electrical loads have been administratively reduced to a level consistent with that identified in the Degraded Grid Study performed by PSE&G in 1981.
8612090025 861126 A3P1 PDR ADOCK 05000311
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Mr.
W.
F.
Kane, Director 2
11/26/86 As identified in our presentation, we propose to operate the Salem Station by limiting electrical loads to the continuous load rating of the 4kV system cables and by operating Salem Unit 2 with the non-safety related group busses split between their respective station power transformers and the No. 2 auxiliary power transformer.
Salem Unit 1 will operate with all electrical loads supplied by the station power transformers with the following exception; the No. 11 condensate pump and the No. 12 heater drain pump will be powered from separate Unit 2 group busses.
This configuration was analyzed by our consultant, PTI, and it was determined that in all cases 4kV system voltages remained above the 91% relay setpoint for degraded grid protection.
A copy of the PTI analysis is provided as Attachment 1 to this letter.
The revised Justification for Continued Operation and supporting 10CFR50.59 analysis are provided in Safety Evaluation S-C-E-130-NSE-0549-0 (Attachment 2).
In the course of the presentation, a number of questions were raised by members of your staff.
Several of those questions related to the credentials of our consultant and the level of verification / validation which was applied to the computer model utilized in the Salem electrical distribution system transient analysis.
These matters have been investigated to the extent practical and the results of those investigations are summarized in Attachment 3.
An additional concern relative to plant specific data on Degraded Grid (91%) relay setpoint drift is still being reviewed.
Preliminary review of the plant specific data indicates that excessive drift has not been a problem at Salem Station.
A review of vendor data has been completed and confirms that setpoint drift should not be a concern for the operating regime of the relays installed at Salem.
We trust that this information will be useful in reviewing our proposal for operating the Salem Station as described above.
As discussed in our meeting, we are prepared to address in a follow-up meeting in early December any additional questions you and your staf f may have relative to this matter.
Until then, should you have any questions please feel free to contact us.
Sincerely, C#M'M Attachments
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Mr. W.
F. Kane, Director 3
11/26/86 C
-Mr.
D. C. Fischer.
Licensing Project Manager
.Mr. T. J.
Kenny Senior Resident Inspector I
Mr.
O. Chapra i
Nuclear Reactor Regulation 4
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