ML20086D798

LAR to License DPR-22,revising TS to Extend Surveillance Test Intervals & Allowable out-of-svc Times for Selected Instrumentation

ML20086D798
Person / Time
Site:	Monticello
Issue date:	07/05/1995
From:	Hill W NORTHERN STATES POWER CO.
To:
Shared Package
ML20086D796	List: ML20086D794 ML20086D798 ML20086D801
References
NUDOCS 9507100388
Download: ML20086D798 (10)

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UNITED STATES NUCLEAR REGULATORY COMMISSION I- NORTHERN STATES POWER COMPANY l Monticello Nuclear Generating Plant Docket No. 50-263 k

REQUEST FOR AMENDMENT TO OPERATING LICENSE DPR-22 LICENSE AMENDMENT REQUEST DATED July 5,1995 Northern States Power Company, a Minnesota corporation, requests authorization for changes to Appendix A of the Monticello Operating License as shown on the attachments labeled  :

Exhibits A, B and C. Exhibit A describes the proposed changes, describes the reasons for the changes, and contains a Safety Evaluation, a Determination of Significant Hazards Consideration and an Environmental Assessment. Exhibit B contains current Technical Specification pages marked up with the proposed changes. Exhibit C is a copy of the Monticello Technical Specifications incorporating the proposed changes.  ;

l This letter contains no restricted or other defense information.

l NORTHERN STATES POWER COMPANY By Y Y'dtn W J Hill "'

Plant Manager Monticello Nuclear Generating Plant l

On thisN day of b /64f before me a notary public in and for said County, personally appeared'W J Hill, Plant' Manager, Monticello Nuclear Generating Plant, and being first duly sworn acknowledged that he is authorized to execute this document on behalf of Northern States Power Company, that he knows the contents thereof, and that to the best of  ;

his knowledge, information, and belief, the statements made in it are true and that it is not j interposed for delay.

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ll JUDYL KLAPPERICK $

j; NOTARY PUBLIC41NNESOTA d

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$ Wy Comme Espires Sept. 29,1997

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l EXHIBIT A j l

Monticello Nuclear Generating Plant License Amendment Reauest Dated July 5.1995 Evaluation of Proposed Changes to the Technical Specifications for Operating License DPR-22 Pursuant to 10 CFR Part 50, Section 50.59 and 50.90, the holders of Operating License DPR-22 hereby propose the following changes:

BACKGROUND This amendment, Part 2 of the Monticello Surveillance Test Interval / Allowed Outage Time (STl/AOT) Program, extends the surveillance test intervals and allowable out-of service times for selected instrumentation. The proposed changes will minimize unnecessary testing and remove excessively restrictive out-of service times that could potentially degrade overall plant safety and availability.

Prior to approving amendment No. 81 to the Monticello Nuclear Generating Plant Technical '

Specification, the NRC Staff found the analysis in General Electric Topical Reports NEDC-30844 and NEDC-30851P acceptable to support the determination that current on-line Reactor Protection System test intervals were consistent with the high availability required by Generic Letter 83-28, item 4.5.3. The NRC Staff also found the use of the analyses acceptable for supporting the proposed extensions to Technical Specification Surveillance Test intervals (STis) and increases in Allowable Out-of-service Times (AOTs). The NRC issued its Safety Evaluation Report on July 15,1987, along with conditions for plant-specific application for proposed Technical Specification changes and close-out of Generic Letter 83-28, item 4.5.3.

As follow-on items, the NRC Staff found acceptable extension to Technical Specification STis and increases in AOTs for isolation instrumentation, as documented in their Safety Evaluations for General Electric Topical Reports NEDC-30851P, Supplement 2, and NEDC-31677P, dated January 6,1989 and June 18,1990, respectively.

The General Electric methodology for changing instrument functional testing from monthly to quarterly was found to be acceptable provided the generic analyses was shown to be applicable to the specific plant and instrument drift expected with the extended functional test interval was within the margins of the methodology.

l Exhibit A Page 2 of 9 On April 16,1992, the NRC staff found NSP's Technical Specification change submittal on STI and AOT time limits for common instrumentation serving the reactor protection system and containment isolation system acceptable (Amendment No. 81) as Part 1 of a two part change.

This present submittal, Part 2, proposes to complete our Technical Specification changes related to Generic Letter 83-28, item 4.5.3. surveillance interval revisions by extending surveillance test intervals and allowable out-of-service times for instrumentation in the ECCS, Rod Block, Isolation Group 4 (HPCI), and Isolation Group 5 (RCIC), Reactor Building Ventilation & Standby Gas Treatment, Recirculation Pump Trip and Alternate Rod injection, and Shutdown Cooling Supply isolation systems.

PLANT SPECIFIC ANALYSIS The following generic and specific GE documents were reviewed to determine applicability of MNGP instrumentation, and are used as references in this amendment request:

1. NEDC-30851P-A, Technical Specification improvement Analysis for BWR Reactor Protection System, March 1988.

2. NEDC-30851P-A, Supplement 1, Technical Specification improvement Analysis for BWR Control Rod Block Instrumentation, October 1988.

3. NEDC-30851P, Supplement 2, Technical Specification Improvement Analysis for BWR lsolation Instrumentation Common to RPS and ECCS Instrumentation July 1986.

4. NEDC-30936P-A, BWR Owners' Group Technical Specification improvement Methodology (With Demonstration for BWR ECCS Actuation Instrumentation) Part 1, December 1988.

5. NEDC-30936P-A, BWR Owners' Group Technical Specification improvement Methodology (With Demonstration for BWR ECCS Actuation Instrumentation) Part 2, December 1988.

6. NEDC-31677P-A, Technical Specification improvement Analysis for BWR isolation Actuation Instrumentation, July 1990.

7. GE Report RE-006, " Technical Specification improvement Analysis for the Emergency Core Cooling System Actuation instrumentation for Monticello Nuclear Plant", January 1987.

8. GENE-770-06-1-A," Bases for Changes to Surveillance Test intervals and Allowed Out-of-Service Times for Selected instrumentation Technical Specifications", December 1992.

! Exhibit A l

Page 3 of 9

9. GENE-770-06-2-A, " Addendum To Bases for Changes to Surveillance Test Intervals

and Allowed Out-of-Service Times for Selected Instrumentation Technical Specifications", December 1992.

10. OG6-120-12, Letter from Lynne Rash (GE) to BWROG Technical Specification Improvement (TSI) Committee Members .... Northem States Power, " Plant -Specific Technical Specification improvement Analysis for the Reactor Protection System",

March 7,1986.

11. OG9-131-32D, Letter from J.F.Klapproth (GE) to BWR Owners' Group Technical Specification Committee - D, "NRC Safety Evaluation for Isolation Instrumentation Common to RPS and ECCS Instrumentation", February 8,1989.

12. OG90-319-32D, Letter from W.P.Sullivan (GE) to Millard L. Wohl (NRC), " Clarification of Technical Specification Changes Given in ECCS Actuation Instrumentation Analysis", March 22,1990.  ;

13. OG92-584-32D, Letter from J.D. Friday and W.P.Sullivan (GE) to BWR Owners' Group Technical Specification Committee - D, " Clarification to Plant-Specific Technical Specification Improvement (TSI) Analysis for Emergency Core Cooling System (ECCS) )

Actuation Instrumentation", July 9,1992.

We have reviewed the GE generic and plant specific analyses and concluded that they are applicable to the Monticello Nuclear Generating Plant. The table below identifies the Technical Specification areas being revised and the primary documents used in the review.

Tech Spec Description GE Document - references ECCS 4,5,7,11 Rod Blocks 2 HPCI (Group 4 ) Isolation 6 RCIC (Group 5 ) Isolation 6,8,9,12 Reactor Building Vent & SBGT 3, 6 Recire Pump Trip & Altemate Rod injection 8 Shutdown Cooling Supply isolation 6,1 INSTRUMENT DRIFT ANALYSIS To address the setpoint drift issue, a drift analysis was performed on each instrument channel whose surveillance intervat is being extended. The analysis was done per the guidance provided by the NRC in a letter dated April 27,1988 to the BWR Owners' Group. The NRC Staff stated that,

• Licensees should examine plant and/or generic data from representative instrument channels over a sufficier.t period to demonstrate that the setpoint drift expected ,

with the extended STis is within the margins established using their current methodology. If the drift expected with the extertded STis is not within the allowance established using their 1

i

l Exhibit A Page 4 of 9 current methodology, a larger allowance should be incorporated into the setpoint calculation to account for the increased drift."

To address the setpoint drift issue in the amendment proposal, Monticello has analyzed plant specific drift which could be expected. Drift has been shown to remain within required allowance for all instruments with the exception of PS 2-3-52A, " Low Reactor Pressure ECCS Valve Permissive". For this instrument, appropriate hardware changes will be made to address the additional drift prior to implementation of the Technical Specification change.

Proposed Chances a) On page 30, revise Note "A". by deleting the phrase "within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />" and add "(ref.

3.1.B)"in the Note A header. Also on page 30, note "b."; correct typographical error of "functionin" to " function in".

b) On page 32, for

• Mode Switch in Shutdown", change "Each refueling outage" to "Every operating cycle."

c) On page 33, Note 2, delete ". . and on high steam line radiation once per shift".

d) On page 34, Table 4.1.2, revise minimum frequency of Recirculation Flow Meters &

Flow instrumentation from *Every 3 months" to *Every Operating Cycle (5)". Also, add note 5 to say: "A sensor check shall be performed on APRM recirculation flow signals once per day."

e) On page 42, change " amplifies" to " amplifiers".

f) On page 50, add that HPCI Steam Lines are Group 4, and RCIC Steam Lines are Group 5.

g) On page 51, delete portions of Notes (1) and (2) that pertained only to Groups 4 & 5, and delete " Groups 1,2 and 3"in Notes (1) and (2) so the notes refer to all the groups. !

In Note 1, add "(a shared channelis considered one channel).

h) On pages 52,53, and 54, add Note 6 to the column on " Minimum No. of Operable or Operating Trip Systems". On page 55, revise Note 3, and add Note 6.

i) On page 59, revise placement of note references so they are allin one column. Add Notes 5 and 6.

j) On page 60d, revise Note 1, add Note 2. For RCIC initiation, correct " Total No. of ,

instrument Channels Per Trip System", and " Minimum No. of instrument Channels Per l Trip System" columns. Change Required Condition A, to reference the specific section i of the Technical Specifications that pertains to the applicable condition. On the end of i Required Condition C, add "for HPCI, or B for RCIC".

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Exhibit A  ;

Page 5 of 9 k) On pages 61 and 62, Table 4.2.1, extend the instrument channel test frequency for the j ECCS Instrumentation, Rod Blocks, HPCI (Group 4) Isolation, RCIC (Group 5) Isolation, )

Reactor Building Ventilation & Standby Gas Treatment, Recirculation Pump Trip and i Altemate Rod injection, and Shutdown Cooling Supply isolction from Once/ month to j Once/3 months as shown. j l

Reason for Chances I

a) The proposed deletion of "within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />"in Note A on page 30 removes a potential  :

conflict with section 3.1.B.3, which states " place and maintain the plant under the l specified required conditions using normal operating procedures." The time frame is defined by specifying the use of normal operating procedures and the "within 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />" l phrase is not needed. Eliminating "within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />"is consistent with similar sections of the Montice'lo l Technical Specifications.

Also on page 30, a typographical error was corrected.

b) On page 32, "Each refueling outage"is being changed to "Every operating cycle" for consistency with wording elsewhere.

c) On page 33, deletion of ". . and on high steam line radiation once per shift"is to remove notation that should have been removed as part of revision 133 approved 8/18/92 when the high steam !ine radiation scram was deleted and removed from the Monticello Technical Specifications.

d) During review of the STI's, it was determined that the quarterly calibration interval for  !

the APRM flow converter was very conservative compared to other similar electronic 1 instrument loops. Calibration at the proposed interval will minimize unnecessary testing i that could potentially degrade overall plant safety and availability.

The flow referenced APRM scram and rod block are only active below 75% drive flow.

Above 75% drive flow, the APRM scram and rod block setpoints are fixed at nominally l

120% and 108% respectively. The plant operates below 75% drive flow only during i startup, shutdown, or power reductions for maintenance activities. This represents a very small percentage of the operating cycle.

A drift analysis has been performed which shows that by extending the calibration interval from 3 months to once every operating cycle, the allowed margin for drift will not be exceeded.

When extending the surveillance interval of the recirculation flow meters and instrumentation, the potential exists for a recirculation flow signal to drift higher (non-conservative) than its actual value. This occurrence would be detected by the flow comparator function of the system. Each flow converter contains a comparator circuit which provides a Rod Withdraw Block alarm if the output signals of the two converters l

Exhibit A Page 6 of 9 should deviate by more than a preset value. This function will be checked every operating cycle as indicated above.

A daily sensor check comparing each flow converter output will provide early detection of any drift and indicate if calibration is needed.

e) Changing "which employ amplifies" to "which employ amplifiers"is essentially correcting a typographical error. Although " amplifies"is a word, it is not used correctly in this context.

f) The addition of (Group 4) and (Group 5) in the HPCI Steam Lines and RCIC Steam Lines titles provides additional descriptive infonnation and makes the wording of these two titles consistent with the three tities earlier irt the same section. This addition does not change the meaning or function of the sections.

g) As part of Phase 1 of the STl/AOT time extension amendment request, Notes 1 and 2 of Table 3.2.1 (page 51) were divided up to recognize new AOT requirements for the instrumentation on the extended (3 month) surveillance cycle. Since the present request will put the remaining instrumentation on a 3 month STI, Part 2 deletes the old wording and places the same AOT requirements on the remaining instrumentation.

The extension of AOTs provides time to perform testing or to make repairs without significantly affecting overall instrumentation failure frequency, or plant safety. The wording proposed for the Phase 2 instrumentation is identical to the wording approved in Phase 1 with the addition of the phrase "(a shared channelis considered one channel)". This phrase is being added to clarify that a shared channelis treated as a single channel. The change is consistent with the AOT recommended by GE and its implementation in the Improved Technical Specifications.

h) Revision of Note 3 on page 55 provides time to perform testing or to make repairs without significantly affecting overall instrumentation failure frequency, or plant safety.

This is again consistent with the GE references.

Addition of Note 6 is to add the 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> out-of-service time for performance of surveillance without tripping the system. The addition of the phrase "(a shared channel is considered one channel)"is being added to clarify that a shared channelis treated as a single channel.

Changes on pages 52, 53, and 54 are to tie the " Minimum No. of Operable or i Operating Trip Systems" column to the new Note 6.

i) On page 59, placement of applicability notes has been rearranged to place them allin the column titled " Min. No. of Operable of Operating Instrument Channels Per Trip ,

System". This should lessen the chances that any notes would be overlooked.

Exhibit A Page 7 of 9 The addition of Notes 5 and 6 again add the extension of AOTs times to perform testing or to make repairs for the Low Low Reactor Water Level and High Drywell Pressure functions without significantly affecting overall instrumentation failure frequency, or plant safety The wording proposed for the Phase 2 instrumentation is identical to the wording approved in Phase 1. The change is consistent with the AOT recommended by GE.

j) On page 60d, Note 1 is revised to include statement to allow 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> out-of-service time for one inoperable instrument channel. Note 2 is new and adds the 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> out-of-service time for performance of surveillance without tripping the system. Wording is similar to that already used in Note 1 of Table 3.2.1 and approved in Part 1 of the STl/AOT amendment.

For RCIC Initiation,

• Minimum No. of Operable of Operating instrument Channels Per Trip System" and " Total No. of Instrument Channels Per Trip System" are being corrected from 2 to 4. These are errors that have been in this table since it was first added. Electrical print NX-7822-22-2 was reviewed to verify the revised numbers are correct.

Note 1 has been revised to add the allowable 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> AOT as discussed above. Also in Note 1, " Turbine /Feedwater Trip only" is being deleted since it is not applicable to Table 3.2.8.

Note 2 has been added to provide for the 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> surveillance AOT using the same wording as approved in Part 1 of the STl/AOT amendment.

Required Condition A has been revised to reference the specific section of the Technical Specifications that pertains to the applicable condition. This section,3.5.A, ECCS Systems, provides the specific LCO's to be entered into, and thus is more descriptive than just listing the allowable modes. The revision is consistent with other sections of the Technical Specifications. In conjunction with this change to Required Condition A, in Required Condition C, the addition of "for HPCI, or B for RCIC" provides separate pointers to the correct Technical Specification sections pertaining to HPCI and RCIC.

k) The Technical Specification changes for instrumentation STI extensions as proposed on pages 61 and 62 will increase safety and improve plant operation. The improvement is achieved by reducing the potential for unnecessary plant scrams, thereby reducing challenges to plant shutdown systems, and by reducing excessive cycles on equipment, thus improving plant availability. In addition, the elimination of unnecessary testing results in a potential safety gain and operation improvement by improving utilization of personnel and resources required for testing activities, by decreasing personnel radiation exposure, and reducing equipment wearout potential.

i Exhibit A i Page 8 of 9 l Safety Evaluation and Determination of Sianificant Hazards Considerations  !

The proposed change to the Operating License has been evaluated to determine whether it l constitutes a significant hazards consideration as required by 10 CFR Part 50, Section 50.91 l using standards provided in Section 50.92. This analysis is provided below; i

1. The proposed amendment will not involve a sianificant increase in the orcoability or consecuences of an accident previously evaluated.

The maximum failure frequency change is for the ECCS Actuation Instrumentation as identified by General Electric topical report NEDC-30936P-A, and Monticello specific report RE-006. These reports concluded core damage frequency changed by less than 4% when STis were increased to once per 3 months, AOTs for surveillance were increased to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and AOTs for repair were increased to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Since this small increase was within the guideline of acceptability stated in NEDC-30936P-A, and Monticello only proposes to increase the repair AOT to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> rather than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, this amendment will not cause a significant increase in the probability or consequences of an accident previously evaluated for the Monticello plant (see RE-006).

l The drift analysis determined the associated instrumentation would not be adversely effected with the longer calibration intervals. Pertinent process parameters including instrument drift will still be within acceptance criteria with the longer surveillance l intervals. )

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The recirculation flow meters and flow instrumentation are not used in any safety or j accident analysis. Therefore, no analysis would be changed by increasing the  !'

calibration interval to once per cycle.

2. The proposed amendment will not create the possibility of a new or different kind of accident from any accident previously analyzed.

These changes only affect the instrument STI and AOT times. No changes are being made to the functions of the instrumentation. Therefore, the proposed amendment will not create the possibility of a new or different kind of accident.

3. The proposed amendment will not involve a sianificant reduction in the marain of safety.

l These changes willimprove the performance of equipment and are intended to reduce the potential for equipment failures due to unnecessary testing. The safety limits and the limiting safety system setpoints will not be affected by these changes, No safety margins are affected, therefore, the drift will remain within the margins of safety. ]

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Exhibit A Page 9 of 9 Environmental Assessment Northern States Power has evaluated the proposed changes and determined that:

1. The changes do not involve a significant hazards consideration, 9

2. The changes do not involve a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or

3. The changes do not involve a significant increase in individual or cumulative occupational radiation exposure.

Accordingly, the proposed changes meet the eligibility criterion for categorical exclusion set forth in 10 CFR Part 51 Section 51.22(c)(9). Therefore, pursuant to 10 CFR Part 51 Section 51.22(b), an environmental assessment of the proposed changes is not required.

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