ML18096A709
| ML18096A709 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 05/11/1992 |
| From: | Labruna S Public Service Enterprise Group |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NLR-N91115, NUDOCS 9205190302 | |
| Download: ML18096A709 (14) | |
Text
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 - Nuclear Operations ttiAY l t 1992 NLR-N91115 LCR 89-06 United States Nuclear Regulatory commission Document Control Desk Washington, D.C. 20555 Gentlemen:
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 In accordance with the requirements of 10CFR50.90 1 Public Service Electric and Gas Company (PSE&G) is transmitting a request to amend Facility Operating Licenses DPR-70 and DPR-75, for Salem Generating Station (SGS) Unit Nos. 1 and 2.
Pursuant to the requirements of 10CFR50.90 (b) (1), a copy of this request has been sent to the State of New Jersey.
The proposed changes revise the Reactor Trip System (RTS) and Engineered Safety Features Actuation System (ESFAS)
Instrumentation Sections and associated Bases, for Surveillance Test Intervals (STI) and Allowed Outage Times (AOT).
These changes are line item improvements previously approved by the NRC and documented in Safety Evaluations for WCAP-10271 and Supplement 1, WCAP-10271 Supplement 2 and Supplement 2 Revision 1, and the Supplemental Safety Evaluation for WCAP-10271 Supplement 2 Revision 1.
PSE&G has evaluated the following issues associated with implementing the proposed changes: applicability of generic conclusions to Salem Units 1 and 2, setpoint calculation allowance for instrumentation drift, and plausible common mode failure mechanisms.
- 1)
The Process Control System and Solid State Protection system used at Salem were specifically modelled in the generic analyses.
Salem Unit 2 utilizes Functional Unit 9 (Semi-Automatic Switchover to the Containment Sump.on Refueling Water Storage Tank Low Level), which was not part of the generic program.
- A plant specific evaluation confirmed acceptability of this Functional Unit.
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Document Control Desk NLR-N91115 2
MAY 1 l 1992
- 2)
We have reviewed the setpoint methodology employed at Salem.
The values used in the Salem Units 1 and 2 setpoint methodology properly account for drift associated with extended STis.
- 3)
A PSE&G Engineering Evaluation reviewed failure mechanisms and plausible common failure modes that could be introduced or impacted by extended STis.
No existing common mode failure mechanisms were identified.
We will have procedures in-place for common cause failure evaluation prior to the requested implementation date.
PSE&G believes that the proposed changes result in plant safety improvements through:
- 1)
Reduced number of inadvertent reactor trips and ESFAS actuations, due to less frequent testing.
- 2)
Improved equipment repairs and reliability, due to longer allowed outage times.
- 3)
Improved operating staff effectiveness in monitoring and controlling plant operations, due to less frequent operating shift distractions from surveillance testing.
This amendment request is similar to those submitted and approved for Indian Point 3, Wolf Creek, and Diablo Canyon.
Attachment A contains further discussion and justification for the proposed revision.
Attachment B is a markup of the existing Unit 1 Technical Specifications to reflect the requested changes.
Attachment C is a markup of the existing Unit 2 Technical Specifications to reflect the requested changes.
PSE&G has reviewed the implementation requirements for the proposed amendment and requests a 120 day implementation period after amendment approval.
Document control Desk NLR-N91115 3
MAY l t 1992 Should you have any questions on this transmittal, please contact us.
Affidavit Attachments C
Mr. J. C. Stone Sincerely, Licensing Project Manager - Salem Mr. T. Johnson Senior Resident Inspector 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
STATE OF NEW JERSEY COUNTY OF SALEM
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SS.
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REF:
NLR-N91115
- s. 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 dated MA.'< 1 1 1912
, concerning the Salem Generating Station, Unit Nos. 1 and 2, are true to the best of my knowledge, information and belief.
Subscribed and Sworn to before me this II My Commission expires on I
1992 ELIZABETH J. KIDD Notary Public of New Jersey My Commission Expires April 25, 1995
PROPOSED LICENSE CHANGE SALEM GENERATING STATION UNIT NOS. 1 AND 2 ATTACHMENT A FACILITY OPERATING LICENSE NOS. DPR-70 AND DRP-75 DOCKET NOS. 50-272 AND 50.311 I.
Background
LCR 89-06
- 1.
History of the Westinghouse Owners Group Program Many utilities expressed concern over the level of testing and maintenance requirements, and their impact on plant operation, particularly in instrumentation systems.
The Westinghouse Owners Group (WOG) initiated a program to respond to these concerns, by developing a justification for revising generic and plant specific Instrumentation Technical Specifications.
This program is documented in WCAP-10271 and its supplements, and referred to as the Technical Specification Optimization Program (TOPS).
Many operating plants experienced inadvertent reactor trips and safeguards actuations while performing instrumentation surveillances.
These actions resulted in unnecessary plant transients and safety system challenges.
Plant personnel devote a significant amount of time and effort to performing, documenting, reviewing, and tracking required surveillance activities.
Many of these surveillances seemed unwarranted due to the high level of equipment reliability.
An opportunity for significant benefits existed through revised instrumentation test and maintenance requirements.
The NRC Staff issued a Safety Evaluation Report (SER) for WCAP-10271 and supplement 1 in a letter dated February 21, 1985 (Reference 1).
The SER approved quarterly testing, 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to place a failed channel in a tripped condition, and increased AOT for testing RTS analog channels.
Quarterly testing was required on a staggered basis.
The Staff issued a Supplemental SER (SSER) for WCAP-10271 Supplement 2 and Supplement 2 Revision 1 in a letter dated April 30, 1990.
The SSER approved STI and AOT extensions for the ESFAS functions included in Appendix A2 of WCAP-10271, Supplement 2, Revision 1.
The approved functions include:
Safety Injection, Steam Line Isolation, Main Feedwater Isolation, and 'Auxiliary Feedwater Pump Start Signals.
Appendix A2 configurations are not addressed in the Westinghouse Standard Technical Specifications (STS).
The SER and SSER allow identical relaxations for the RTS and ESFAS analog channels, eliminating the special conditions previously imposed on shared analog channels.
1
The Salem Unit 2 Solid State Protection System includes Functional Unit 9; Semi-Automatic Transfer to Recirculation on Refueling Water Storage Tank (RWST) Low Level.
This Functional Unit is not part of the generic TOPS Program.
However, relaxation is necessary to support extended AOTs for the Automatic Actuation Logic, and Actuation Relays associated with Functional Units relaxed by WCAP-10271.
Since the logic and actuation relays are a single system, if any Functional Unit employed in the system is not eligible for relaxation, that Functional Unit becomes the limiting factor.
Westinghouse has completed a plant-specific evaluation of Functional Unit 9 (Reference 6) for PSE&G's Salem Unit 2.
Westinghouse used the generically approved methodology and AOT/STI relaxations to determine the change in functional availability.
The results indicated an automatic function decreased availability, that corresponds to the lowest values calculated for any Functional Unit in the generic TOPS Program approved by the NRC Staff.
- 2.
Hardware Modifications Plant modifications are not required to implement the requested changes.
WCAP-10271 allows testing in the bypass mode, but Salem Units 1 and 2 do not have bypass testing capability for any RTS or ESFAS analog instrumentation, with the exception of the Containment Pressure High-High channels.
II.
Description of Changes This amendment request proposes to revise Salem Unit 1 and 2 Technical Specification Sections 3/4.3.1 (RTS) and 3/4.3.2 (ESFAS) as follows:
- 1.
Limiting Condition for Operation 3.3.1.1 A.
Table 3.3-1
- 1)
(Units 1 and 2) Functional Units 11 thru 15 and 18.
Change applicable ACTION from 7 to
- 6.
- 2)
(Units 1 and 2) Functional Units 19 and 22.
Change applicable ACTION from 1 to 10.
ACTION 10 is added to implement a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> maintenance and 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> surveillance AOT for
- the appropriate functions.
2
- 3)
(Units 1 and 2) ACTIONS 2 and 6.
Change the time an inoperable channel may be maintained in an untripped condition from 1 to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
Allow placing the inoperable channel in bypass while testing another channel in the same function, instead of placing the tested channel in bypass.
Change the time an inoperable channel may remain in bypass to support testing another channel in the same function from 2 to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
- 4)
(Units 1 and 2) ACTION 7.
Delete and mark NOT USED.
- 5)
(Units 1 and 2) ACTION 11.
Change the time an inoperable channel may be maintained in an untripped condition from 1 to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
B.
Table 4.3-1
- 1)
(Units 1 and 2) Functional Units 2, 3, 4, 6, 7 I 8 I 9 I 10 I 11, 12 I 14 I 15 I 16 I and 17.
Change CHANNEL FUNCTIONAL TEST frequencies frommonthly to quarterly.
- 2)
(Units 1 and 2) Notation (1) is changed from 7 to 31 days.
- 2.
Limiting Condition for Operation 3.3.2.1 A.
Table 3.3-3
- 1)
(Units 1 and 2) Functional Units 1.c, 1.d, 1.f (three places), 4.d (three places), 5.a, 8.c.i, and 8.c.ii.
Change the applicable ACTION from 14 to 19.
- 2)
(Units 1 and 2) ACTIONS 13 and 20.
Change to include a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> maintenance AOT.
(Unit 1 only) Add the words "provided the other channel is OPERABLE" to ACTION 13 and the words "per specification 4.3.2.1 provided the other channel is OPERABLE" to ACTION 20.
- 3)
(Units 1 and 2) ACTION 16.
Change the time an inoperable channel may be maintained in an unbypassed condition from 1 to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and increase the time that another channel in the same function may be bypassed to allow testing from 2 to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
3
- 4)
(Units 1 and 2) ACTION 19.
Change the time an inoperable channel may be maintained in an untripped condition from 1 to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
Allow placing the inoperable channel in bypass while testing another channel in the same function, instead of placing the tested channel in bypass.
Change the time an inoperable channel may remain in bypass to support testing another channel in the same function from 2 to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
- 5)
(Unit 2 only) Functional Unit 9.b.
Change applicable ACTION from 13 to 20.
B.
Table 4.3-2
- 1)
(Units 1 and 2) Functional Units 1.c, 1.d, 1
- e, 1. f, 2
- c, 3
- b
- 3, 4. c, 5. a, and 8. c
- Change CHANNEL FUNCTIONAL TEST frequency from monthly to quarterly.
- 2)
(Units 1 and 2) Functional Unit 8.d.
Change CHANNEL FUNCTIONAL TEST frequency from monthly staggered (Unit 1) and monthly (Unit
- 2) to quarterly.
- 3)
(Units 1 and 2) Functional Unit 9.a.
Change CHANNEL FUNCTIONAL TEST from monthly to quarterly.
III. Justification for the Proposed Changes Increasing the RTS and ESFAS instrumentation STis minimizes the potential number of inadvertent reactor trips and ESFAS actuations.
Less frequent surveillance testing is estimated to result in 0.5 fewer inadvertent reactor trips per unit, per year.
Increasing the STis enhances the operational effectiveness of plant personnel.
Reducing the amount of time devoted to surveillance testing allows manpower reallocation to tasks such as preventive maintenance.
Increased AOTs result in fewer human factors errors, since more time is allotted to perform corrective actions.
WCAP-10271 results indicate that the reduction in testing frequency and the increase in maintenance AOTs do not adversely affect public health and safety.
The results of the plant-specific evaluation for Functional Unit 9, Automatic Switchover the Containment Sump on RWST Low Level, also supports this conclusion.
The proposed changes will reduce the number of inadvertent reactor trips and ESFAS actuations, and support a greater level of managed plant resources.
4
IV.
Response to Safety Evaluation Report Imposed Conditions The WOG evaluated the impact of the proposed STI and AOT changes on Core Damage Frequency (CDF) and public risk in WCAP-10271 and its supplements.
The NRC Staff concluded in their review of these documents, that the overall upper bound of the CDF increase is less than 6% for Westinghouse PWR plants.
The Staff expected actual CDF increases for individual plants substantially below 6%.
This CDF increase is small when compared to the range of uncertainty in the CDF analysis, and therefore acceptable.
The Staff did not require a staggered test strategy for ESFAS channel testing, and eliminated this previous requirement for RTS analog channel testing.
This decision resulted from the relatively small contribution of the analog channels to RTS/ESFAS unavailability, process parameter signal diversity, and normal operational testing sequencing.
Our proposed changes are consistent with NRC SERs dated February 21, 1985 (Reference 1), February 22, 1989 (Reference 2), and April 30, 1990 (Reference 5).
These SERs are associated with WCAP-10271, WCAP-10271 Supplement 1, WCAP-10271 Supplement 2, and WCAP 10271 Supplement 2 Revision 1 respectively.
Functional Unit 9, Automatic Switchover to the Containment Sump on RWST Low Level, is not part of the TOPs generic program.
Westinghouse completed a plant-specific evaluation for PSE&G's Salem Unit 2.
This evaluation determined the change in availability when the generically approved AOT and STI were applied to this function.
The evaluation yielded less than a 12% decrease in automatic function availability.
This corresponds to the lowest value for any Functional Unit in the generic program.
We anticipated these results since this function utilizes a 2 out of 4 configuration, with a minimum of modules in each loop.
The final switchover actions are manually completed.
Emergency Operating Procedures specify automatic action verification.
Thus, the decrease in automatic function has no impact on the ultimate success of the switchover evolution.
Staff approval of the TOPS generic program changes is contingent upon confirmation that certain conditions are met.
Although WCAP-10271 Supplement 2 and WCAP-10271 Supplement 2, Revision 1 specifically apply to ESFAS instrumentation, PSE&G has imposed the conditions described in WCAP-10271 and WCAP-10271 Supplement 1 for RTS instrumentation to the ESFAS, as appropriate.
These conditions also apply to the Functional Unit not covered by the generic program; where appropriate.
PSE&G provides the following responses to the required conditions.
5
- 1.
The RTS SER (Reference 1, page 10) states that approval of an increase in STI from once per month to once per quarter, for the analog channel operational tests, is contingent on performance of testing on a staggered test basis.
The ESFAS SER (Reference 2, page 4 of enclosure 1) removed this requirement.
PSE&G Response - Neither Salem Unit implemented staggered testing for the RTS function, so this SER condition has no impact.
B.
The RTS SER (Reference 1, page 10) states that approval of items related to extending STI is contingent on procedures in-place to require failure evaluation for common cause and additional testing, if necessary.
PSE&G Response -
Salem Units 1 and 2 will have procedures in-place for common cause failure evaluation and any required additional testing, prior to the requested implementation date.
Thes~
procedures will be consistent with the "Westinghouse Owners Group Guidelines for Preparing Submittals Requesting Revision of Reactor Protection System Technical Specifications, Revision 1, 11 which received NRC Staff review and approval.
- c.
The RTS SER (Reference 1, page 10) states that approval to extend STI and AOT for channels that provide dual inputs to other safety related systems, such as ESFAS, only applies to the RTS function.
PSE&G Response -
The extensions generically approved for the ESFAS analog channels are now the same as the RTS analog channels.
This condition is not applicable to Salem since the relaxations requested are the same for channels shared by the RTS and ESFAS.
D.
The RTS SER (Reference 1, page 10) states that approval of channel testing in a bypassed condition is contingent on the capability of the RTS design to support such testing without lifting leads or installing temporary jumpers.
6
PSE&G Response -
Salem Units 1 and 2 do not have bypass testing capability for any RTS or ESFAS analog instrumentation, with the exception of the Containment Pressure High-High channels.
Extending bypass testing capability to other channels requires plant modifications.
We do not anticipate installing these modifications in the near term.
Thus, approval for bypass testing is not requested at this time.
E.
The RTS SER (Reference 1, page 9) states that acceptance is contingent on confirmation that the instrument setpoint methodology includes sufficient margin to offset the drift anticipated as a result of less frequent surveillance.
PSE&G Response -
We have evaluated Salem Units 1 and 2 setpoint drift per "Westinghouse owners Group Guidelines for Preparing Submittals Requesting Revision of Reactor Protection System Technical Specifications, Revision 1, 11 which receive NRC Staff review and approval.
PSE&G has determined that the values used in the Salem Unit 1 and 2 setpoint methodology properly account for drift associated with extended STis.
- 2.
The ESFAS SER (Reference 2, Table 1 of enclosure
- 1) states that the licensee must confirm generic analysis applicability to their specific plant.
PSE&G Response -
The generic analysis used in WCAP-10271 and Supplements is applicable to Salem Units 1 and 2.
Salem Units 1 and 2 use the Westinghouse 7100 Process Control System and the Westinghouse Solid State Protection System for RTS and ESFAS.
Both of these systems were specifically modelled in the generic analyses.
All of the requested ESFAS Functional Unit relaxations are addressed by the generic analysis, with the exception of functional Unit 9 on Unit 2.
Westinghouse addressed Functional Unit 9 on a plant-specific basis for PSE&G (Reference 6).
They determined that this Functional Unit has less than a 12% decrea'se in availability.
This value corresponds to the lowest calculated value for any Functional Unit in the generic program.
The generic program determined that an availability decrease of less than 12% was acceptable.
7
B.
The ESFAS SER (Reference 2, Table 1 of enclosure
- 1) states that the licensee must confirm that any increase in instrument drift due to the extended STis is properly accounted for in the setpoint calculation methodology.
PSE&G Response -
Same as RTS Condition E above.
V.
Significant Hazards Analysis Consideration The proposed Technical Specification changes:
- 1.
Do not involve a significant increase in the probability or consequences of an.accident previously evaluated.
SERS issued for WCAP-10271, WCAP-10271 Supplement 1, WCAP-10271 Supplement 2 and WCAP-10271 Supplement 2, Revision 1 document the determination that the proposed changes are within acceptable limits.
Implementation of the proposed changes decreases the total Reactor Protection System (RPS) yearly availability, primarily due to less frequent surveillance testing.
Decreased availability causes a higher probability of Anticipated Transient Without Scram (ATWS), with an associated increase in the core melt contribution resulting from an ATWS.
Decreased ESFAS availability slightly increases the CDF.
The proposed changes result in a significant reduction in the core melt probability from inadvertent reactor trips.
This reduction is primarily attributable to less frequent survei-llance testing.
The reduction in inadvertent reactor trip core melt frequency is large enough to counter the increase in ATWS core melt probability, resulting in an overall reduction in total core melt probability.
The WOG determined values for the increase in CDF were documented in the WCAP, and independently verified by Brookhaven National Laboratory, as part of an NRC staff audit and sensitivity analysis.
Based on the small increase in CDF compared to the range of uncertainty, the increase is considered acceptable.
Salem Functional Unit 9, evaluated on a plant-specific basis, falls within the same criteria and is considered acceptable.
Therefore, it may be concluded that the proposed changes do not increase the severity or consequences of an accident previously evaluated.
The proposed changes do affect the probability of RPS failure, but do not alter the manner in which protection is afforded, nor the manner in which limiting criteria are established.
8
- 2.
Do not create the possibility of a new or different kind of accident from any previously evaluated.
The proposed changes do not involve hardware modifications or result in changes to RPS provided plant protection.
RPS functionally is not altered.
Therefore, it may be concluded that the proposed changes do not create the possibility of a new or different kind of accident from any previously evaluated.
- 3.
Do not involve a significant reduction in a margin of safety.
The proposed changed do not alter the manner in which Safety Limits, Limiting Safety System Setpoints, or Limiting Conditions for Operation are determined.
The impact of reduced testing is a longer time interval over which instrument uncertainties (e.g., drift) may act.
Experience indicates that the initial uncertainty assumptions are valid for reduced testing.
Therefore, it may be concluded that the proposed changes do not involve a significant reduction in a margin of safety.
VI.
Conclusions Implementation of the proposed changes results in plant safety and resource improvements through:
- 1.
Reduced number of inadvertent reactor trips and ESFAS actuations, due to less frequent testing.
- 2.
Improved equipment repairs and reliability, due to longer allowed outage times.
- 3.
Improved operating staff effectiveness in monitoring and controlling plant operations, due to less frequent operating shift distractions from surveillance testing.
Based on the information presented above, PSE&G has concluded that the proposed Technical Specification changes satisfy the criteria for a no significant hazards consideration.
9
VII. References
- 1.
"Safety Evaluation by the Office of Nuclear Reactor Regulation Review of Westinghouse Report WCAP-10271, and WCAP-10271 supplement 1 on Evaluation of Surveillance Frequencies and Out of Service Times for the Reactor Protection Instrumentation System," dated February 21, 1985.
- 2.
"Safety Evaluation by the Office of Nuclear Reactor Regulation Review of Westinghouse Report WCAP-10271 Supplement 2 and WCAP-10271 Supplement 2, Revision 1 on Evaluation of Surveillance Frequencies and Out of Services Times for the Engineered Safety Features Actuation System," dated February 22, 1989.
- 3.
WCAP-10271 Supplement 1-P-A, "Evaluation of Surveillance Frequencies and Out of Service Times for the Reactor Protection Instrumentation System," dated May 1986.
- 4.
WCAP-10271-P-A Supplement 2, Revision 1, "Evaluation of Surveillance Frequencies and Out of Service Times for the Engineered Safety Features Actuation System," dated May 1989.
- 5.
Supplemental Safety Evaluation for WCAP-10271 Supplement 2, Revision 1, dated April 30, 1990.
- 6.
Technical Specification Optimization Program, Semi Automatic Transfer to Recirculation on RWST Level Low for Salem Generating Station Unit 2.
10