ML18096A896
| ML18096A896 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 08/14/1992 |
| From: | Labruna S Public Service Enterprise Group |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML18096A897 | List: |
| References | |
| GL-91-11, NLR-N92086, NUDOCS 9208240015 | |
| Download: ML18096A896 (8) | |
Text
-*
J Public Service Electric and Gas Company Stanley LaBruna Public Service Electric and Gas Company P.O. Box 236, Hancocks Bridge, NJ 08038 609-339-1200 Vice President - Nuc.lear Operations AUG 14 1992 NLR-N92086 United states Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Gentlemen:
SUPPLEMENTARY RESPONSE TO GENERIC LETTER 91-11 REQUEST FOR AMENDMENT SALEM GENERATING STATION UNIT NOS. 1 AND 2 FACILITY OPERATING LICENSE NOS. DPR-70 AND DPR-75 DOCKET NOS. 50-272 AND 50-311 The purpose of this letter is to provide additional information regarding control of vital instrument buses at the Salem Generating Station, and, in accordance with 10 CFR 50.90, to request an amendment to Facility Operating License DPR-70 for Salem Unit No. 1.
Pursuant to the requirements of 10 CFR 50.91(b) (1), a copy of this request for amendment has been sent to the State of New Jersey. contains a description of procedural controls on the "D" vital instrument bus inverters, which are not included in the Salem Technical Specifications. describes the proposed changes to Technical Specification 3.8.2.1, "AC Distribution - Operating" and 3.8.2.2, "AC Distribution - Shutdown", including PSE&G's determination of No Significant Hazards Consideration.
The changes would make the Unit 1 vital instrument bus inverter Limiting Conditions of Operation and Action Statements identical to those of Unit 2. contains the affected Technical Specification pages with the proposed changes.
Attachment Affidavit
__ r}_,!
~-----
- -920.8240015 920814-- -- ---~
Document Control Desk NLR-N92086 c
Mr. J. C. Stone Licensing Project Manager Mr. T. Johnson Senior Resident Inspector 2
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 AUG 14 1992
STATE OF NEW JERSEY REF:
COUNTY OF SALEM Stanley LaBruna, being duly sworn according to law deposes and says:
I am Vice President - Nuclear Operations of Public Service Electric. and Gas Company, and as such, I find the matters set forth in our letter, NLR-N92086, concerning the Salem Generating station, Unit Nos. 1* and 2, are true to.the best of my knowledge, information and belief.
7~ /
Subscribed and sworn to before me this /L/cjfi day of ~
~k~
, 1992
/NOtacyUblic ~rsey SHERRY L. CAGLE NOTARY PUBLIC OF NEW JERSEY My Commission expires on ~~~~M~y_C_om_m_i_ss_io_n~E~xp=ir=es~M=a=rc~h-5~1~99-Z~
. NLR-N92086 ATTACHMENT 1 Controls on 110 11 Vital Instrument Bus Generic Letter 91-11 requested each operating reactor licensee to ensure its plant has procedures, including time limitations and surveillance requirements, for vital instrument buses and inverters, and manual tie breakers that can cross connect Class lE buses (ac or de).
For plants without procedures covering each of the above, the generic letter requested an evaluation justifying the licensee's position.
As described in our response dated January 31, 1992, Salem Units 1 and 2 each have four 115 V AC vital instrument buses (VIB's) and three trains of vital AC power.
Salem Unit 1 and 2 Technical Specifications, and implementing procedures, establish the operability and surveillance requirements for the A, B and C VIB's.
The "D" VIB is fed from the B power supply,* and is not included in the Technical Specifications.
The "D" VIB has been added to the surveillance procedure for AC distribution systems.
This procedure requires the inverter output voltage and frequency to be within the specified limits, and verification of proper system configuration using checklists for breaker position, indicating light status and switch position.
The revised procedure directs the operator to issue a priority A work order for an inoperable "D" inverter during plant operation in Modes 1 through 4.
Priority A work orders require immediate action, and are used for equipment with Technical Specification Action requirements of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or less.
In order to address "D" inverter failures discovered independent of surveillance activities (e.g., inverter trouble alarm indication in the control room), the inverter operating procedures have been revised.
.These procedures also require an A priority work order for an inoperable "D" inverter, during plant operation in Modes 1 through 4.
The operating procedures limit "D" inverter inoperability for preventive maintenance, during plant operation in Modes.* 1 through.. 4, to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
. NLR-N92086 ATTACHMENT 2 DESCRIPTION OF THE PROPOSED CHANGE
- 1)
Unit 1 Technica1*specification 3.8.2.1, "A.C.
Distribution - Operating" a) Add a separate Action Statement for an inoperable inverter.
With one inverter inoperable, the Action statement would require the associated bus to be energized within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and the inoperable inverter to be restored to operable within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, or the unit would be shutdown.
b) Revise the existing Action Statement to be consistent with the Limiting Condition of Operation (LCO), by changing "OPERABLE" to "OPERABLE and energized".
- 2)
Unit 1 Technical Specification 3.8.2.2, "A.C.
Distribution -
Shutdown."
Add "energized from its respective inverter connected to its respective D.C. bus train" to the LCO for the 115 volt Instrument Bus.
REASON AND JUSTIFICATION FOR THE PROPOSED CHANGE The proposed changes would make Unit 1 LCO's and Action Statements for Unit 1 inverters identical to those of Pnit 2.
- 1)
Unit 1 Technical Specification 3.8.2.1, "A.C. Distribution -
Operating" a) The addition of a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> allowed outage time (AOT) for an inoperable inverter is consistent with revision 4 of the Westinghouse Standard Technical Specifications.
With an inoperable inverter, the proposed Technical Specifications would require the associated bus to be energized within eight hours.
This is consistent with the present action requirements for an inoperable or deenergized AC bus.
Total loss of any Vital Instrument Bus requires immediate recovery actions via Abnormal Operating Procedure.
With the inverter inoperable and the bus energized, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> would be allowed to restore the inverter to operable status.
24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is based on engineering judgement, in consideration of time needed for inverter troubleshooting and repair, vs.
the need to minimize the risk of momentarily losing the instrument bus due to loss of the preferred (offsite) AC power supply.
The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> AOT was included in Salem Unit 2's original Technical Specifications.
- Attachment 2 NLR-N92086 -------
b) Changing "OPERABLE" to "OPERABLE and energized" for proposed Unit 1 Technical Specification 3.8.2.l Action a, would make the action statement consistent with the LCO, which presently requires the AC buses to be operable and energized.
- 2)
Technical Specification 3.8.2.2, "A. C. Distribution -
Shutdown."
Adding "energized from its respective inverter connected to its respective D.C. bus train," to the LCO for the 115 volt Instrument Bus, is consistent with PSE&G's present interpretation of vital instrument bus and inverter operability requirements.
The 115 V AC surveillance requirements are identical for both Salem units.
They include verification that the bus is energized through the inverter's AC power feed, and that the inverter is capable of transferring to the DC power supply upon loss of AC power.
NO SIGNIFICANT HAZARDS CONSIDERATION The proposed changes to the Salem Unit 1 Technical Specifications:
- 1)
Do not involve a significant increase in the probability or consequences of an accident previously evaluated.
The proposed changes would revise Technical Specification 3.8.2 to make the Unit 1 vital instrument bus Limiting Conditions of Operation {LCO) and action statements identical to those of Unit 2.
The proposed changes do not alter the design or operation of the vital instrument buses or inverters.
The proposed changes would add an allowed outage time {AOT) of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> for one inoperable inverter.
The Unit 1 Technical Specifications presently require restoration of an inverter to operable and energized status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, based on the action statement applicable to the AC buses.
The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period allowed for the inverter would only apply if the affected vital instrument bus remains energized or is re-energized within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> in accordance with the present action statement.
The vital instrument bus* may be energized through a constant voltage transformer in the event the inverter is not available to provide the normal AC power feed.
24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore the inverter to operable status is consistent with standard industry practice (eg., Westinghouse Standard Technical Specifications, revision 4) for allowing restoration of inverter operability without incurring an unacceptable risk of losing a vital instrument bus following a loss of of the preferred (offsite) power source.
The proposed changes would also clarify that the AC distribution system operability requirements include energizing the 115 V AC
- Attachment 2 NLR-N92086 buses through an operable inverter.
These clarifications reflect present practices and are compatible with the Technical Specifications as written.
- 2)
Do not create the possibility of a new or different kind of accident from any accident previously evaluated.
The proposed changes would not introduce any changes to the design or operating configuration of the AC distribution system.
Therefore, the proposed changes do not introduce the possibility of a new or different kind of accident.
- 3)
Do not involve a significant reduction in a margin of safety.
The changes to. the Unit 1 vital instrument bus and inverter Technical Specification requirements are consistent with the present requirements for Unit 2, which have been determined to ensure an acceptable margin of safety relative to AC power availability.
The proposed changes do not involve a significant reduction in any margin of safety.
NLR-N92086 ATTACHMENT 3