ML18153C598

Application for Amends to Licenses DPR-32 & DPR-37,changing Tech Specs to Provide Allowed Outage Times & Operator Actions for Engineered Safeguards Instruments Per WCAP-10271,Suppl 2,Rev 1 & Generic Ltr 89-19

ML18153C598
Person / Time
Site:	Surry
Issue date:	11/08/1990
From:	Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML18152A437	List: ML18152A436 ML18153C598
References
90-195, GL-89-19, NUDOCS 9104170215
Download: ML18153C598 (13)

Text

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.* Novemb~r 8, 1990 United States Nuclear Regulatory Commission Serial No.90-195 Attention: Document Control Desk NOIETS.

Washington, D. C. 20555 Docket Nos. 50-280 50-281 License Nos. DPR-32 DPR-37 Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS l AND 2 ENGINEERED SAFEGUARDS ACTION INSTRUMENT OPERABILITY AND SURVEILLANCE REQUIREMENTS PROPOSED TECHNICAL* SPECIFICATION CHANGE Pursuant to 10 CFR 50.90, the Virginia Electric and Power Company requests amendments, in the form of changes to the Technical Specifications, to Operating Licenses No. DPR-32 and DPR-37 for the Surry Power Station Units 1 and 2 respectively.

These Technical Specification changes provide Allowed Outage Times and Operator Actions for the Engineered Safeguards Instruments in accordance with WCAP 10271, Supplement 2, Revision 1, "Evaluation of Surveillance Frequencies and Out of Service Times for the Engineered Safety Features Actuation System (ESFAS)8 and the NRC Safety Evaluation Reports (SER) dated February 22, 1989 and April 30, 1990. In addition, this request incorporates the operability and surveillance requirements for Feedwater Isolation/Turbine Trip instruments in accordance with GL 89-19, "Safety Implication of Control Systems in LWR Nuclear Power Plants.* Attachment 1 provides a discussion of the proposed Technical Specification Change, while Attachment 2 provides the revised pages.

This request has been reviewed and approved by the Station Nuclear Safety and Operating Committee. It has been determined that the proposed changes do not involve a significant hazards consideration as defined in 10 CFR 50.92. The basis for our no signiflcant hazards consideration determination is included in Attachment 1.

Very truly you~

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Stewart Senior Vice President - Nuclear Attachments r- *?:f6if.fi<):;f15 ':-'0:l 108____ . ~,

PDR ADOCI< O~:i000:2:30

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cc: U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, N. W.

Suite 2900 Atlanta, Georgia 30323 Mr. W. E. Holland NRC Senior Resident Inspector Surry Power Station Commissioner Department of Health Room 400 109 Governor Street Richmond, Virginia 23219

( '

COMMONWEALTH OF VIRGINIA )

)

COUNTY OF HENRICO )

The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by W. L. Stewart who is Senior Vice President - Nuclear, of Virginia Electric and Power Company. He is duly authorized to execute and file the foregoing document in behalf of that Company, and the statements in the document are true to the best of his knowledge and belief.

Acknowledged before me t h i s £ day o f ~ , 19~.

My Commission Expires: ~ 3/ , 19ft.

~-)(&,g Notary Public (SEAL)

( '

01scuss10N OF CHANGE Currently, Surry Technical Specifications do not have allowed outage times (AOT) for the majority of the ir:1struments listed in Tables 3. 7-2 and 3. To provide consistent required operator actions and allowed outage times for the Reactor Protection (Trip)

Instruments and the Er,gineered Safeguards Actuation Instruments Tables 3.7-1, 2 and 3 are being modified. Table 3.7-1, Reactor Trip Instruments, was previously modified in accordance with the Westinghouse Owners Group Topical Report WCAP 10271, Supplement 1 and the NRC Safety Evaluation Report dated February 21, 1985. This proposed Technical Specification change reformats and provides action statements and allowed outage times for each functional unit (instrument) in Tables

3. 7-2 and 3. 7-3. The action statements and allowed outage times are consistent with WCAP 10271, Supplement 2, Revision 1, 'Evaluation of Surveillance Frequencies and Out of Service Times for the Engineered Safety Features Actuation System (ESFAS)" and the NRC Safety Evaluation Reports (SER) dated February 22, 1989 and April 30, 1990. Several additional changes are being incorporated into Table 3.7-1 to maintain consistent action statements and allowed outage times for the instruments that are included in both tables. The surveillance intervals are not being changed to quarterly at this time. Surry Power Station performs surveillance tests of the Reactor Protection and Engineered Safeguards instruments on a monthly basis. To make the Surry Technical Specifications more consistent with Standard Technical Specifications, operability requirements for the reactor protection system and engineered safeguards system interlocks are being included in Tables 3.7-1 & 2. The appropriate surveillance requirements for these interlocks are being added to Table 4.1.

The following specific changes are being proposed:

• TS 3.7.8.2 and C These specifications are bejng deleted and replaced with a standard operability statement for the instruments in Tables 3.7-2 and 3. These statements are no longer necessary because the tables now contain the appropriate action statements and allowed action times for an inoperable channel and minimum channels operable requirement.

• TS 3.7.E.1 and 2 These Specifications have been modified in a previous Technical Specification change request, dated June 29, 1990. This request removes the Radiological Effluent Technical Specifications (RETS) from the Technical Specifications.

• TS 3.7.F.J and 2 These Specifications are the action statements for the accident monitoring instruments listed in Table 3. 7-6. These actions are required for items 1 through 1o in the Table; items 11 through 15 have action statements included on the table as notes. Therefore, we are correcting TS 3.7.F.1 and 2 to address only the applicable instruments. Pages 3.7-1 and 2 were reformatted and pages 3.7-2a and b are being deleted.

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• Table 3.7-1, Reactor Trip Instrument Operating Conditions Action statement 6 is being modified to permit unit startup (REACTOR CRITICAL) with an instrument channel in trip as long as the minimum channel operable requirement is met.

Action statement* 7 is being modified. The existing action statement allows power operatton with an inoperable channel (in trip) until the next scheduled channel functional test. Both WCAP 10271, Supplements 1 and 2, and the NRC Safety Evaluation Reports have eliminated the need for a time limit in this action statement, based on an insignificant increase in core melt frequency when operating with a channel in trip. Therefore, the proposed action statement will permit unit startup (REACTOR CRITICAL) and power operation with an inoperable instrument channel in trip indefinitely. This action is similar to action statement 6 except that, when the "minimum channel operable" requirement is not met, the unit must be placed in cold shutdown rather than just hot shutdown.

This action statement is necessary for those instruments that provide a safety function at hot shutdown. Functional Units 7,8, 12, 14, and 17 are affected.

Action statement 11 is being modified to allow four hours to test the logic train.

This is an increase of two hours to perform the logic train testing. This will allow for the testing to be performed in a more controlled manner thus reducing the probability of human error. The increased time to perform surveillance testing is consistent with the increased time allotted for testing of the Engineered Safeguards Action logic train.s. This increase in the time allowed for testing has been addressed in the NRC's supplemental SER for WCAP 10271, Supplement 2, dated April 30, 1990.

The Reactor Protection system interlocks are being included in Table 3.7-1 with operability requirements and action statements.

Each functional unit in Tables 3.7-2 and 3 was reformatted and provided with an action statement and allowed outage time consistent with WCAP 1 0271, Supplement 2, and the NRC Safety Evaluation Report for this document. The differences between the existing specification and the proposed specification for each functional unit are listed below. Along with the interlocks the automatic actuation logic for the protective functions (e.g., Safety Injection, Containment Isolation, Auxiliary Feedwater, etc) is being included as a functional unit with operability requirements.

• Table 3,Z*2

1. Safety Injection

a. Manya! - requires 2 channels to be operable rather than 1. 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> are provided to make repairs before requiring the unit to be in hot shutdown within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

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b. Hjgh pon~aiorpert pressure

• lnclude.s action to place inoperable channel 1n trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip.

c. High Djfferentjat Pressure

• Includes action to place inoperable channel in trip within- 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip.

Also, it allows a reactor startup and continued power operations with a channel in trip.

d. Pressurizer Low Low Level* Includes action to place inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip.

Also, it allows a reactor startup and continued power operations with a channel_ in trip.

e. High Steam Flow - Includes action to place inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip. Also, it allows a reactor startup and continued power operations with a channel in trip.

f. Automatjc Actuatjon Logjc

• This is a new functional unit. The action provides 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for channel/train repair or complete a unit shutdown. The.

action statement also establishes a time limit to perform surveillance testing.

In this case 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is used to accommodate testing of the relay logic.

2. Containment Spray

a. Manual

• Provides 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to repair circuit or complete a unit shutdown.

This action is more conservative than the WCAP requirement. We have 2 switches that are required to be pushed simultaneously to initiate containment spray.

b. Hiob-Hiob Contajnment pressure

• Includes action to place inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and establishes a time limit to . perform surveillance testing on an additional channel with a channel inoperable and in trip.

c. Automatjc Actuation Logic a This is a new functional unit. The action provides 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> fqr channel/train repair or complete a unit shutdown. The action statement also establishes a time limit to perform surveillance testing.

3. Auxiliary Feedwater (AFW)

a. Steam Generator Law Low Level

• Includes action to place inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> (change from 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />) and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip. Also, it allows a reactor startup and continued power operations with a channel in trip.

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Q b .. B,GF Underyoitage

• Includes action to place inoperable channel in trip within_ 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> (c~ange from 1 h~_ur) and establishes a time limit to perform surveillance testing on an add1t1onal channel with a channel inoperable and in trip. Also, it allows a reactor startup and continued power operations with a channel in trip. This logic scheme was reevaluated and included in the NRC's s~pplemental SER for WCAP 10271, Supplement 2, issued April 30, 199~.

c. Safety lniection

• Requirements of Safety Injection instruments must be met.

d. Statjon Blackout

• No change to existing Technical Specification requirement.

e. Trip of Main Feed Pump

• No change to existing Technical Specification requirement.

f. Automatic Actuation Logjc

• New functional unit. Provides 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> to repair circuiUswitch or complete a unit shutdown and then 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> cooldown to less than 350 degrees and 450 psig. The overall time requirement to reach a condition where this function is not necessary has not changed and remains consistent with the WCAP and NRC's SER.

However, we have changed the time to hot shutdown from 12 to 1O hours and the time to reach 350/450 from 6 to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. This will provide additional time to borate to establish the shutdown margin required by TS and permit a more orderly plant shutdown.

g. Manya!

• AFW does not have a single switch or button that initiates Auxiliary feedwater. The pumps and valves must be operated individually to manually initiate AFW.

4. Loss of Power

a. 4, la Ky Emergency Power <Degraded Y91tage) - Includes action to place inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> (change from 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />) and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip. Also, it allows a reactor startup and continued power operations with a channel in trip.

b.4.16 Ky Emergency Power lUnderyoltage) - Includes action to place inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> (change from 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />) and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip. Also, it allows a reactor startup and continued power operations with a channel in trip.

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5. Nonessential Service Water

a. Low Intake Canal level* Includes action to place an inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> (change from 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />) and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip. Also. it allows a reactor startup and continued power operations with a channel in trip. This is a Surry-specific instrument that performs a safety function.

6. Engineered Safeguards System Interlocks This is a new requirement that will provide operability requirements for each interlock.

• Table 3, 7-3 The Table Functions have been reorganized by phase isolation functional units.

1. Containment Isolation

a. Phase 1

1) Safety !njectjon - Remains the same as existing Technical Specification

2) Aytomatjc Actuation Logjc - This is a new functional unit. The action provides 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for channel/train repair or complete a unit shutdown.

The action statement also establishes a time limit to perform surveillance testing. In this case 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is used to accommodate testing of the relay logic.

3) Manual - Provides 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> to repair circuit/switch prior to requiring the unit be placed in hot shutdown within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

b. Phase 2

1) High Contajnment Pressure - Includes action to place inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip.

-2) Aytgmatjc Actuatjon Logjc

• This is a new functional unit. The action provides 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for channel/train repair or complete a unit shutdown.

The action statement also establishes a time limit to perform surveillance testing. In this case 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is used to accommodate testing of the relay logic.

3) Manyat - Provides 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to repair circuit/switch or complete a unit shutdown.

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'-.,.! c. Phase 3*

1) Hjgh High Contajnment Pressure - Includes action to place inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip.

2) A_utomatjc Actuatjon Logjc - This is a new functional unit. The action provides 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for channel/train repair or complete a unit shutdown.

The action statement also establishes a time limit to perform surveillance testing. In this case 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is used to accommodate testing of the relay logic.

3) Manya! - Provides 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to repair circuit/switch or complete a unit shutdown.

2. Steam Line Isolation

a. High Steam flow - Includes action to place inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip. *

b. Hjgh High Containment Pressure - Includes action to place inoperable channel in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and establishes a time limit to perform surveillance testing on an additional channel with a channel inoperable and in trip.

c. Manya!

• Provides 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> to repair circuit/switch prior to requiring the unit be placed in hot shutdown within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. This is consistent with the WCAP even though we did not use the identical action statement.

d. Aytomatjc Actuatjon Log;c - New functional unit. Provides 1o hours to repair circuit/switch or complete a unit shutdown and then a hours cooldown to less than 350 degrees and 450 psig. The overall time requirement to reach a condition in which this function is not necessary has not changed and remains consistent with the WCAP and SER. However, we have changed the time to hot shutdown from 12 to 1o hours and the time to reach 350/450 from 6 to a hours. This will provide additional time to borate to establish the shutdown margin required by Technical Specifications and permit a more orderly plant cooldown.

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3. Feedwater Isolation Feedwater Isolation is being included under the Turbine Trip and Feedwater Isolation function.

4. Turbine Trip a!'ld Feedwater Isolation

a. Stea*m Generator Water Level - High-High - This is a new item in response to GL 89-19, Request for Action Related to Resolution of Unresolved Safety Issue A-47 "Safety Implication of Control Systems in LWR Nuclear Power Plantsn pursuant to 10 CFR 50.54(f). Operability and surveillance of this instrument will now be required by Technical Specifications. An inoperable channel will be required to be placed in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and unit startup and power operations can continue indefinitely.

b. Automatic Actuation Logic and Actyatjon Belay - This is also a new item. This is necessary to maintain a consistent format with the other ESF and Containment isolation instruments. This item has the same action statement as the other logics associated with Auxiliary Feedwater and Main Steam Isolation.

c. Safety lnjectjon - Remains the same as existing Technical Specification.

• JS 4,1A l & 2 Surveillance requirements are being included for the Reactor Protection and Engineered Safeguards Systems' interlocks. TS 4* 1.A.2 is being deleted. This will eliminate the requirement to test the interlocks prior to each startup if they have not been tested in the past 92 days. Neither WCAP 10271 Supplements .1 or 2 require the additional. interlock operability test if not performed in the previous 92 days. Therefore eliminating the test will not impact the Core Damage Frequency determination in the WCAP.

• Table 4,l*l Surveillance requirements for the Reactor Protection and the Engineered Safeguards Action Interlocks are being included in this table. This addition to the table will delineate the actual surveillance test requirements for the interlocks. In addition, the surveillance requirements for the Feedwater Isolation and Turbine Trip instruments and logic circuit are included in accordance with GL 89-1]. Also, the page numbers for table 4.1*1, 4.1-A, 4.1*1A. and 4.1-1B have been changed.

• Table 4,l *A A description of the Engineered Safeguards Action Interlocks is being included in this table with the Reactor Protection Interlocks.

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e The generic evaluation described in WCAP 10271, Supplement 2. performed by Westinghouse, is applicable for the relay logic system installed at Surry Power Station.

With the exception of one, RCP Undervoltage - Auxiliary Feedwater start, the various logic schemes for the Reactor Protection and Engineered Safeguards Action instruments and interlocks have been included in the Westinghouse Probabilistic Risk Assessment and included in the NRC's Safety Evaluation Report. This one logic scheme has since. been evaluated by Westinghouse and the NRC and has been documented in a supplemental SER issued April 30, 1990.

At this time Surry Power Station is not changing the surveillance frequency of the Reactor Protection and/or the Engineered Safeguards Action instruments and actuation logic circuits. Therefore, instrument drift is not affected and there is no impact on any instrument setpoints.

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e e J SIGNIFICANT HAZARDS CONSIDERATION PEIEBMINATION Virginia Electric and Power Company has reviewed the proposed changes against the criteria of 10 CFR 50.92 and has concluded that the changes as proposed do not pose a significant Hazards consideration. Specifically, the proposed. change will reformat th_e Engine~red Safeguards instruments tables, provide operability requirements for Reactor Protection and Engineered Safeguards interlocks, and provide action statements and allowed outage times consistent with WCAP 10271, Supplement 2, "Evaluation of Surveillance Frequencies and Out of Service nmes for the Engineered Safety Features Actuation System (ESFAS)." Thus, operation of the Surry Power Station in accordance with the proposed changes will not:

1. Involve a significant increase in the probability or consequences of any accident previously evaluated. Based on the Westinghouse/WOG analyses and Brookhaven National Laboratory sensitivity studies of those analyses, the proposed ESFAS changes would have only a small impact on plant risk.

The overall upper bound for the Core Damage Frequency (CDF) increase is less than 6% for the proposed changes which is relatively small compared to the range of uncertainty in the CDF analyses. Since the proposed change does not extend the surveillance frequencies to quarterly, the overall CDF increase will be much smaller than the Westinghouse/WOG analyses projections of 2.4%.

2. Create the possibility of a new or different type of accident from those previously evaluated in the safety analysis report. Physical plant modifications are not being made and overall plant operations are not being changed. Only instrument Allowed Outage nmes, Action Statements, and surveillance requirements are being included or changed. Therefore, new accident precursors are not being generated and no new or different kind of accident is created.

3. Involve a significant reduction in the margin of safety. Plant operations are not changed nor are any of the accident analysis assumptions modified or exceeded by this change. The changes in Allowed Outage Times for Engineered Safeguards Action instruments and Operator Actions with inoperable instruments have no impact on the margin of safety because as long as the minimum channel operable requirements are met the unit is operating within the design basis. Therefore, the accident analysis assumptions remain bounding and safety margins remain unchanged.

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