ML17262A743
| ML17262A743 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 01/31/1992 |
| From: | Rich Smith ROCHESTER GAS & ELECTRIC CORP. |
| To: | Andrea Johnson NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 9202120080 | |
| Download: ML17262A743 (7) | |
Text
ACCELERATED DI UTION DEMONST TION SYSTEM JI REGULATORY INFORMATION DISTRIBUTION SYSTEM (RXDS)
ACCESSION NBR:9202120080 DOC.DATE: 92/01/31 NOTARIZED:
NO DOCKET FACXL:50-244 Robert Emmet Ginna Nuclear Plant, Unit 1, Rochester G
05000244 AUTH.NAME AUTHOR AFFILIATION SMITH,R.E Rochester Gas 6 Electric Corp.
RECIP.NAME RECIPIENT AFFILIATION JOHNSON,A.R.
Project Directorate I-3 R
SUBJECT:
Advises of licensee views on need to re-balance SW cooling I
flows to safety-related coolers,per 911220 exit meeting 6
provides schedule for rebalancing of SWS.
D DISTRIBUTION CODE:
A065D COPIES RECEIVED:LTR g ENCL J SIZE: 3 TITLE: Generic Ltr 89-13 Svc Water Sys Problems Affecting Safety-Related E
NOTES:License Exp date in accordance with 10CFR2,2.109(9/19/72).
05000244 A
RECIPIENT ID CODE/NAME JOHNSON,A INTERNAL'HU,A NRR/PD1-3 EXTERNAL: NRC PDR COPIES LTTR ENCL 1
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1 RECIPIENT XD CODE/NAME REG FILE NSIC..
COPIES LTTR ENCL 1
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D NOTE TO ALL"RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM P 1-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
TOTAL NUMBER OF COPIES REQUIRED:
LTTR 5
ENCL 5
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i Stare ROCHESTER GAS ANDELECTRIC CORPORATION ~ 89 EASTAVENUE, ROCHESTER, N.Y. 14649-0001 ROBERT E. SMITH Senior Vice Preridenr Prodvcrion and Engineering TEI.CPHOIIE AnEACODB ne 546-2700 January 31, 1992 U.S. Nuclear Regulatory Commission Document Control Desk Attn:
Allen R. Johnson Proje"t Directorate I-3 Washington; D.C.
20555
Subject:
R.E.
Ginna Service Water System Operational Inspection (SWSOPI)
Re-balancing of Flow to Safety-Related Coolers
Dear Mr. Johnson:
This letter documents RG&E's position regarding the need to re-balance the Service Water Cooling flows to safety-related coolers at the R.E.Ginna nuclear power station.
The letter is in response to Mr Imbro's request at the NRC SWSOPI exit meeting of December 20, 1991.
That request was based upon the evaluation and conclusions of the NRC's SWSOPI team that the Ginna Service Water System is not balanced in accordance with the original design basis of the Service Water System, that current flow balancing delivers an overabundance of flow to the Diesel/Generator (D/G) Service Water (SW) Coolers and that, conversely, that overabundance of flow toI the D/G SW Coolers may be causing other safety-related SW coolers to have less than optimal flow.
RG&E has reviewed the evaluation and conclusion of the SWSOPI Team as well as re-examined the..original pre-operational testing of the service water system performed in 1969.
RG&E has concluded that the'ervice Water.System, although not currently balanced as originally designed, is nonetheless capable of performing all of its intended safety functions as currently balanced.
Nonetheless,
-RG&E believes that a well-balanced Service Water System would provide optimal flow to all safety-related coolers.
Thus,-we'ave begun the steps necessary to evaluate the optimal flow balancing of the Service Water System accounting for changes in material.,condition and heat transfer performance of the Service Water'System since pre-operationa testing.
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ROCHESTER GAS AND ELEC C CORP.
ATE 1/31/92 Mr. Allen R. Johnson SHEET NO.
2 RG&E's schedule for rebalancing of the Ginna Service Water System is as follows:
RG&E will evaluate and test, the performance of the D/G SW Coolers during the 1992 refueling Outage.
An optimal flow for the D/G,SW Coolers will be determined and set'or the coolers prior to return to power from this outage.
(2)
During the course of, 1992, RG&E will review and enhance the analytical modeling and capability of its existing Service Water hydraulic model so that an analytical basis and test specification for the rebalance of the entire Service Water System is available prior to the 1993 Refueling Outage.
(3)
During the 1993 Refueling Outage, which has already been designated by RG&E for extensive refurbishment work on the Service Water System, RG&E will conduct testing as required to confirm the analytical results of the enhanced hydraulic model and to set optimal flows for each SW cooler.
As a result, the Service Water System flow balance will be optimized when the plant returns to power following the 1993 Refueling Outage.
The basis for the above schedule is that RG&E concurs with the SWSOPI Team that the most critical flow rebalancing required is that for the D/G SW Coolers.
It is expected that this rebalancing will make additional flow available to the Containment Air Coolers (CACs) which are considered by the SWSOPI Team as marginal for the performance of their intended safety functions.
RG&E notes that the SWSOPI Team has suggested rebalancing the D/G SW Coolers prior to the 1992 Refuel outage.
- However, RG&E does not consider it prudent to perform this rebalancing without adequate analytical and test bases since the rebalancing will reduce cooling flow to the Diesel/Generators which are critical to the safety of the unit.
Furthermore, the lake temperatures anticipated between now and the start of the 1992 refuel Outage (scheduled for March, 25 1992) provide an additional margin of safety for the performance of the CACs with their current SW flows.
Specifically, current lake temperatures are approximately 40'F.
They are not expected to exceed 60'F prior to the start of the outage.
Design lake water temperature for the SW System is 80'F.
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ROCHESTER GAS ANP El.EC CORP.
f PATE 1/3 1/92 Mr. Allen R. Johnson J
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SHEET NO.
3 Please contact us if you have any questions or comments on this letter or RGGE's intended course of action.
Ver truly you s, ober mith
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