2CAN079703, Application for Amend to License NPF-6,revising Surveillance Testing Requirements for Facility EFW Sys as Specified in TS 4.7.1.2.Requests That Effective Date for Change Be within 30 Days of Issuance

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Application for Amend to License NPF-6,revising Surveillance Testing Requirements for Facility EFW Sys as Specified in TS 4.7.1.2.Requests That Effective Date for Change Be within 30 Days of Issuance
ML20149K051
Person / Time
Site: Arkansas Nuclear Entergy icon.png
Issue date: 07/21/1997
From: Hutchinson C
ENTERGY OPERATIONS, INC.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20149K053 List:
References
RTR-NUREG-1432 2CAN079703, 2CAN79703, NUDOCS 9707290221
Download: ML20149K051 (9)
v • d • e


Text

Ent:rgy oper;tiona,Inc.

'-e M

IL 1443 5 R 333 HJMM AR 7?801 Td 501 #8 4883 C. Randy Hutchinson Wr bewn Omahrvs ANf)

July 21,1997 l

2CAN079703 j U. S. Nuclear Regulatory Comnussion l

Document Control Desk 1 Mail Station Pl-137 Washington, DC 20555

Subject:

Arkansas Nuclear One- Unit 2 Docket No. 50-368 License No. NPF-6 Technical Specification Change Request Concerning Emergency Feedwater Surveillance Testing Gentlemen:

Attached for your review and approval is a proposed Technical Specification change that revises the surveillance testing requirements for the Arkansas Nuclear One - Unit 2 (ANO-2) emergency feedwater (EFW) system as specified in specification 4.7.1.2. The major components of this change include an extension of the EFW pump surveillance testing frequency, a reduction in the minimum steam generator pressure required to perform the surveillance testing on the turbine driven EFW pump, and a modification to the EFW pump testing requirements to those contained in NUIGG-1432, " Standard Technical Specifications for Combustion Engineering Plants." A complete discussion of all the proposed changes to I this specification are included in the attached submittal. I The proposed change has been evaluated in accordance with 10 CFR 50.91(a)(1) using criteria in 10 CFR 50.92(c) and it has been determined that this change involves no significant hazards considerations. The bases for these determinations are included in the attached submittal.

Entergy Operations requests that the effective date for this change be within 30 days of issuance and prior to the completion of the outage currently scheduled for February 1998.

9707290221 970721 PDR ADOCK 05000368 P PDR WM llll!O!!!#l1!#l1lll31.13lll11ll1.1l

U. S. NRC

'Juy l 211997

> 2CAN079703 Page 2 l

Very truly 'ours g

W f C rc

Attachments To the best of my knowledge and belief, the statements contained in this submittal are true.

SUBSCRIBED AND SWORN TO before e , a Notary Public in and for 4W&pu County and the State of Arkansas, this c7 day of AMZ ,1997.I ff Ad Ed/W /

140 tar [Public My Commission Expires XI$v' // #D00 y <

cc: Mr. Ellis W. Merschoff Regional Administrator  !

U. S. Nuclear Regulatory Commission Region IV.

611 Ryan Plaza Drive, Suite 400

, Arlington, TX 76011-8064 NRC Senior Resident Inspector Arkansas Nuclear One P.O. Box 310 London, AR 72847 Mr. George Kalman NRR Project Manager Region IV/ANO-1 & 2 U. S. Nuclear Reg,ulatory Commission NRR Mail Stop 13-H-3 One White Flint North 11555 Rockville Pike Rockville, MD 20852 Mr. David D. Snellings Director, Division ofRadiation Control and Emergency Management 4

Arkansas Department of Health 4815 West Markham Street Little Rock, AR 72205

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., l s

ATTACHMENT

, IQ i

2CAN079703 PROPOSED TECHNICAL SPECIFICATION AND

! RESPECTIVE SAFETY ANALYSES IN THE MATTER OF AMENDING -

4 LICENSE NO. NPF-6 ENTERGY OPERATIONS. INC.

i ARKANSAS NUCLEAR ONE. UNIT TWO l

DOCKET NO. 50-368 i

' Att:chment to i

'2CAN079703 l Page1of6

., DESCRIPTION OF PROPOSED CIIANGES

  • SR 4.7.1.2.b was added to incorporate testing of both emergency feedwater (EFW) pumps in accordance with specification 4.0.5. This change allowed the removal of the current SRs 4.7.1.2.a.1 and 4.7.1.2.a.2 which previously performed this function.
  • The required steam generator pressure for the turbine driven EFW pump in the proposed i SR 4.7.1.2.b.1 was reduced from greater than 800 psia to greater than 700 psia.
  • SR 4.7.1.2.b.1 was also modified to require the surveillance test to be completed within 24 l hours of readting a steam generator (S/G) pressure of 700 psia for the turbine driven EFW
pump. This change allowed the removal of the exception to the 4.0.4 provisions due to j the addition of the requirement to complete the test within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of reaching a S/G
pressure of 700 psia.

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  • The words "during shutdown" were removed from proposed SR 4.7.1.2.c.

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  • The SR for the turbine driven EFW train flow path verification (currently SR 4.7.1.2.b.4) j was rewritten and renumbered to proposed SR 4.7.1.2.d. This SR was rewritten to include the electric driven EFW train flow path verification. This SR was also modified by l '

the removal of the exception to the 4.0.4 provisions because of the addition of the requirement to perform the SRs prior to entering MODE 2 whenever the plant has been in MODES 4,5,6, or defueled for > 30 days.

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  • The bases for Technical Specification (TS) 3/4.7.1.2 was modified by the addition of bases l for specifications 4.7.1.2.b.1 and 4.7.1.2.d. The numerical value for which the reactor j coolant system can be cooled down to on a total loss of off-site power and the temperature at which shutdown cooling may be placed in operation was changed from 350 F to Shutdown Cooling (SDC) entry conditions consistent with the ITS.

BACKGROUND The Arkansas Nuclear One - Unit 2 (ANO-2) EFW system is a two train system consisting of one electric driven and one turbine driven pump each capable of feeding either of the two S/Gs. The system is designed to provide a safety grade backup source of feedwater to the S/Gs when needed to meet the cooling requirements for accidents analyzed in the Safety Analysis Report (SAR). The EFW system provides the feedwater to the S/Gs as necessary to assure the decay heat and residual heat can be removed at a rate such that the fuel design limits and the design conditions of the reactor coolant pressure bounaaty are not exceeded.

The EFW system removes decay heat until the plant has been cooled and depressurized

' , Attachment to l 2CAN079703 Page 2 of 6

. sufficiently to permit the use of the SDC system. The EFW system can also be used during normal startups and shutdowns along with the main and auxiliary feedwater systems.

By letter dated August 4,1992, (2CAN089204) Entergy Operations requested and received Amendment 131 dated October 2,1992 (2CNA109203) to the ANO-2 TS. This amendment reduced the secondary steam supply pressure requirements from greater than 865 psig to a S/G pressure of greater than 800 psia for the turbine driven EFW pump surveillance test. This change was necessary due to an RCS hot leg temperature reduction in order to inhibit a S/G tube damage mechanism. The RCS hot leg temperature reduction resulted in a significant reduction in the steam pressure in the S/Gs.

I Since RCS hot leg temperature reduction, ANO-2 has continued inspecting the S/G tubes and removing them from service when they meet the plugging criteria. The S/G steam pressure has continued to decrease as more of the S/G tubes have been removed from service. The

. S/G secondary side steam pressure is expected to challenge the current TS value of > 800 psia after the S/G inspection currently scheduled for February 1998. The proposed value of > 700 psia will allow adequate steam pressure for the testing of the turbine driven EFW pump and should be adequate to account for S/G tube plugging until the S/Gs are replaced. The ANO-2 S/Gs are scheduled for replacement in the fall of 2000.

l The reliability and performance of both trains of EFW for ANO-2 is excellent and improving. ,

This is based upon reliability trending in support of the maintenance rule assessment of both l l trains back to 1988. The unavailability for both trains combined for the last calendar year was i 14.9 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br />. This low unavailability is well below the industry average for a two train configuration and is one indicator of excellent system performance.

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The system reliability is also excellent and improving for both trains of EFW. This is l monitored by recording all starts and run hours for both trains and calculating a start probability and run probability for each train. The current start probability fer each train for ,

the last three years is 100%. During this time there were no failures to start for surveillance l testing or actual demand since 1994 for the steam driven pump. ANO-2 has never experienced a failure of the motor driven train to start back to 1988 when start attempts were l first monitored. The run probability for the motor driven train is 100% with no failures to run after being started ever recorded. The turbine driven train has a run probability of above 95%

with no failures to run after being started since a failure to run in 1989.

DISCUSSION OF CHANGE Changing the electric and turbine driven EFW pump surveillance frequency from monthly to quarterly is a TS line item improvement listed in Generic Letter 93-05, "Linc-Item Technical Specification Improvements To Reduce Surveillance Requirements For Testing During Power Operation." The quarterly surveillance frequency for the EFW pumps is also consistent with the current revision of NUREG-1432, " Standard Technical Specifications Combustion Engineering Plants" (ITS).

, Attachment to 2CAN079703 Page 3 of 6

. TS Thsk Force change number 101 (TSTF-101) is a change to the ITS that affects the surveillance frequency of the EFW pumps. TSTF-101 modified the ITS surveillance I

frequency from quarterly, to a frequency that is "in accordance with the inservice testing program." TSTF-101 has been approved by the NRC and can be adopted by those plants converting to the ITS. Since AN ' b2 has previously committed to implementation of the ITS (0CAN069502), these changes have been modified to be consistent with the ITS in the current TS format. The remaining differences between the current specifications and the ITS will be addressed during the conversion process.

ANO-2 implements the inservice testing program via specification 4.0.5. Requiring this test to be performed in accordance with specification 4.0.5 is consistent with how the High and j Low Pressure Safety Injection pumps, Coolant Charging pumps, and Containment Spray pumps are required to be tested in specifications 4.5.2.f, 4.1.2.4, and 4.6.2.1.b. The inservice testing program requires testing of these pumps on a quarterly frequency.

The minimum required steam generator pressure for the turbine driven EFW pump was reduced from greater than 800 psia to greater than 700 psia in the proposed SR 4.7.1.2.b.l.

The bases for the ITS states that this SR should be deferred until suitable test conditions v.

' l established. This deferral is required because there is an insufficient steam pressure to  !

perform the test before entering the mode of applicability. Suitable test conditions are )

established by deferring the surveillance test until S/G pressure is greater than 700 psia.  !

, The turbine driver expected performance curve shows that a steam inlet pressure of 300 psia available to the trip and throttle valve is sufficient to develop the full turbine horsepower for the required flowrate and discharge pressure. The maximum head loss for these conditions has been calculated to be less than 100 psi from the S/Gs to the trip and throttle valve. Based on a S/G supply pressure of greater than 700 psia, the steam pressure at the trip and throttle valve will exceed 600 psia. This will result in a 300 psi margin between the TS minimum allowed S/G pressure and that required for the turbine to develop the required turbine horsepower. Therefore, the proposed reduction in the minimum allowed S/G pressure will not affect the turbine driven EFW pump's capability to deliver the required flowrate e.nd discharge pressure during operation.

SR 4.7.1.2.b.1 was also modified by the removal of the exception from the specification 4.0.4 provisions and the addition of the applicable exception for this specification extracted from the ITS. The current exception from the provisions of specification 4.0.4 allows entry into the mode of applicability (mode 3) without completion of the SR. This exception is necessary because the SR can not be completed until the plant is heated up sufliciently to establish the required S/G pressure or suitable test conditions. The addition of the requirement to have this SR completed within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after reaching a S/G pressure of 700 psia clarifies the existing exception so that future interpretation of these requirements will no longer be necessary. The current SR is required to be performed on the turbine driven EFW pump within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of entering mode 3 as required by specification 4.0.3. However, there are situations when the plant could be heated up into mode 3 but not > 800 psia S/G pressure within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This change allows 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from the time when the plant exceeds the minimum required steam pressure of > 700 psia, before requiring completion of the surveillance test.

' Attachment to l l

'2CAN079703 Page 4 of 6

,. ' The words "during shutdown" were removed from proposed SR 4.7.1.2.c. These words are not defined terms in the ANO-2 TS and therefore create the need for interpretation. Removal

of these terms is consistent with the applicable SRs located in the ITS and no requirements
could be found that would require these SRs to be done m a specific mode.

The SR for the turbine driven EFW train flow path verification currently located in SR l l 4.7.1.2.b.4 was revised in accordance with the ITS and renumbered to 4.7.1.2.d. The 18 l month surveillance requirement was modified to the ITS format by requiring performance of ,

s the SR prior to entering mode 2 whenever plant has been below mode 3 for > 30 days. The  :

proposed revision to this SR includes a new electric driven EFW train flow path verification l and the removal of the exception to the 4.0.4 provisions. i i \

! As stated in the bases for the ITS, the operability of the EFW flow paths must be verified l 4

before sufficient core heat is generated that would require the operation of the EFW system during a subsequent shutdown. The frequency is reasonable, based on engineering judgment

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and other administrative controls, to ensure that flow paths remain operable. To further ,

ensure EFW system alignment,t' he operability of the flow paths is verified following extended outages to determine that no misalignment of valves has occurred. This SR ensures that the flow path from the condensate storage tank (CST) to the S/Gs is properly aligned by requiring a flow verification. The CST is considered as the primary EFW system water source which is j consistent with the requirements of the current SR.

l The EFW train flow path verifications in the proposed SR,4.7.1.2.d are consistent with the '

applicable SR located in the ITS. The new requirement to ensure the performance of the surveillance requirement before entering mode 2 is considered more restrictive than the current exception to the provisions of specification 4.0.4. The current specification would i allow entry into mode 2 as long as the surveillance was completed within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of entering mode 3.

The bases for TS 3/4.7.1.2 was completely rewritten to be more consistent with the ITS and I to add bases for the SRs 4.7.1.2.b.1 and 4.7.1.2.d. The values listed in the bases for this specification to which the reactor coolant system can be cooled down to on a total loss of off site power was modified from 350 F to SDC entry conditions. The use of the term of SDC  !

entry conditions instead of an actual temperature is consistent with the philosophy used in the ITS. The SDC entry conditions (SDC mode) are discussed in section 3.6.6.3 of the safety analysis report.

Additional administrative changes were proposed by this submittal that include the renumbering of the current SR 4.7.1.2.a.3 to proposed SR 4.7.1.2.a.1 and the current SR 4.7.1.2.b to proposed SR 4.7.1.2.c.

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! Attachment to j

2CAN079703 Page 5 of 6 l , DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION l

- An evaluation of the proposed change has been performed in accordance with 1

10 CFR 50.91(a)(1) regarding no significant hazards considerations using the standards in l 10 CFR 50.92(c). A discussion of these standards as they relate to this amendment request l follows:

Criterion 1 - Does Not Involve a Significant Increase in the Probability or

! Consequences of an Accident Previously Evaluated. i

, The proposed changes included in this amendment request are being made to the emergency I feedwater (EFW) system technical specification (TS) surveillances. These changes include ,

surveillance interval modifications, allowances to perform the turbine driven EFW pump  !

j surveillance at a lower steam generator (S/G) pressure, removing the requirements to perform i specific EFW surveillance requirements (SRs) during plant shutdowns, bases changes, and i various administrative changes. These changes are consistent with the applicable SRs located i in NUREG-1432 and have therefore been previously approved by the NRC.

I These changes do not alter the functional characteristics of any plant component and do not allow any new modes of operation of any component. The accident mitigation features of the

plant are not affected by the proposed amendment request. No modifications have been made to the EFW system due to this amendment request. Although the minimum steam generator
pressure has been reduced for the turbine driven EFW pump testing, calculations show that j 4

significant margin exists between the proposed value and that needed to adequately perform 1 the test. The capability of the EFW pumps to perform their required safety function is not l impacted by this change. The addition of the electric driven EFW flow path verification will

) help to assure proper alignment of both trains ofEFW following extended outages.

The accident mitigation features of the plant are not affected by the proposed amendment. No modification has been made to the pump or turbine driver. The capability of the turbine driven EFW pump to perform its required function is not impacted by this change. The EFW pumps will be tested in accordance with the more restrictive of the data points required by the safety analysis or the inservice testing program. Therefore, this change does npf involve a significant increase in the probability or consequences of any accident previously evaluated.

Criterion 2 - Does Not Create the Possibility of a New or Different Kind of Accident from any Previously Evaluated.

No new possibility for an accident is introduced by modifying the proposed specifications for the surveillance testing of the EFW pumps. The EFW surveillance requirements will continue to demonstrate the pump's ability to perform its safety function. The modifications to the proposed EFW surveillance requirements are consistent with the current revision of NRC approved NUREG-1432, " Standard Technical Specifications Combustion Engineering Plants" (ITS). Therefore, this change does not create the possibility of a new or different kind of accident from any previously evaluated.

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, Attachment to

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2CAN079703 Page 6 of 6

. Criteiion 3 - Does Not Involve a Significant Reduction in the Margin of Safety.

The safety function of the EFW system is not altered as a result of this change. The capability of the EFW pumps to perform their required function is not impacted by this change. The capacity of the EFW pumps is not impacted by this change. The EFW pumps will be tested and proven operable in accordance with the more restrictive of the data points required by the safety analysis or the inservice testing program. The addition of the electric driven EFW flow ,

path verification will help to assure proper alignment of both trains of EFW following-extended outages. Therefore, this change does nql involve a significant reduction in the margin of safety.

Therefore, based upon the reasoning presented above and the previous discussion of the amendment request, Entergy Operations has determined that the requested change does DQ1 involve a significant hazards consideration.

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