ML18096A671
| ML18096A671 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 04/29/1992 |
| From: | Miltenberger S Public Service Enterprise Group |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-88-002, IEB-88-2, NLR-N92021, NUDOCS 9205050016 | |
| Download: ML18096A671 (3) | |
Text
Public *service Electric and Gas Company*
Steven E. Miltenberger Public Service Electric and Gas Company P.O. Box 236; Hancocks i3~idge, NJ 08038 609~339-1100 Vice Preside.nt and Chief Nuclear Officer APR 2 '.I~
NLR.;,,,N92021 United States Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Gentlemen:
NRC BULLETIN 88-02 RAPID PROPAGATING FATIGUE CRACKS IN STEAM GENERATOR TUBES SALEM GENERATING STATION
-UNIT NOS. 1 AND 2 DOCKET NOS. 50-272 AND 50-311 By letter dc;tted August 16, 1990, the NRC Staff issued the Safety Evaluation addressing Public Service Electric & Gas Company 1.s *
(PSE&G) *response to NRC Bulletin 88-02, Rapid Propagating Fatigue Cracks in Stea:m Generator Tubes.
As required by th.at letter PSE&G is provid°ing*notification of implementation of the administrative controls required by the Safety Evaluation.
PSE&G is also providing information on steam generator tube plugging that was performed during the current refueling outage (2R6) at Salem Unit 2 as a result of the NRC Bulletin 88-02 concern.
. Al though* both the Salem Uni ts have currently plugged less th.an
- 3~% of the steam generator tubes, an analysis to demonstrate acceptability to 10% tube plugging has been completed by Westinghouse. *.Station procedures ensure that if 3.5% tube
~lu~ging is exceededi engineering is notifie~ to evaluate the
-increased tube plugging.
When necessary, procedures will be revised tO permit the 10% tube plugging limit.
During the analysis performed to address 10% steam generator tube plugging, eight additional tubes for Salem Unit 2 were identified as requiring plugging and stabilization.
There are no tubes for Salem Unit 1 that required plugging as. a result of the NRC Bulletin 88-02 evaluation to io% steam generator tube plugging.
9205050016 920429 PDR ADOCK 05000272 G
Document Control Desk NLR-N92021 2
During the* current Unit 2 refuel.ing outage (2R6), the following tubes, identified during the analysis, were plugged and dampeners installed.
The cold leg ends of these tubes are plugged using sentinel plugs with a o. 0135 inch diameter hole. **
Steam Generator 21 R9C59 R9C60 Steam Generator 22 R8C61 R10C46 RlOC50 R11C16 R11C17 steam Generator 23 R8C59 Additionally, tubes R9C59 and RlOC60 in steam Generator 24, which had been plugged and stabilized with stabilizers previously, were modified to install sentinel plugs with a 0.0135 inch diameter hole in the cold leg ends.
Thus, all Salem Unit 2 steam generator tubes plugged and stabilized to address the NRC Bulletin 88-02 concern have a sentinel plug.
This option provides engineering margin against rupture and provides a demonstrated safety position through use of the sentinel plugs.
By the letter referenced above, the NRC staff allowed termination of the PSE&G enhanced leak rate monitoring.
However, PSE&G administratively, will maintain it~ enhanced leak rate monitoring program.
This program is designed to detect steam generator.tube leakage prior to tube rupture, by monitoring radiation levels in the steam generator blowdown and the condenser off gas.
If primary to secondary leakage of 140 gpd is reached, indicative of a
f~st developing steam generator tube crack; procedures are in place at both units to commence. an orderly shutdown.
This leakage limit is significantly lower than the 288 gpd recommendation in NRC Bulletin 88-02.
Should there be any questions with regard to this submittal, please do not hesitate to contact'us.
Sincerely,
Document Control Desk NLR-N92021 C
Mr. J. c. Stone Licensing Project Manager Mr. T. Johnson Senior Resident Inspector 3
Mr. T. Martin, Administrator Region I Mr. Kent Tosch, Chief New Jersey Department of Environmental Protection Division of Environmental Quality Bureau of Nuclear Engineering CN 415 Trenton,_NJ 08625 APR 2 '.! 1W2