ML20085G387

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Proposed Tech Specs Extending Surveillance Test Intervals for Control Rod Sys to Support 24 Month Operating Cycles
ML20085G387
Person / Time
Site: FitzPatrick Constellation icon.png
Issue date: 06/15/1995
From:
POWER AUTHORITY OF THE STATE OF NEW YORK (NEW YORK
To:
Shared Package
ML20085G345 List:
References
NUDOCS 9506200184
Download: ML20085G387 (12)
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JAFNPP ,

3.3 UMITING CONDITION FOR OPERATION 4.3 SURVEILLANCE REQUIREMENT 3.3 REACTIVITY CONTROL 4.3 REACTIVITY CONTROL Analicehility: Apolacatulatv:

Applies to the operational status of the Control Rod System. Applies to the surveillance requirements of the Control Rod System.

4 Obiective: Obiective:

To assure the ability of the Control Rod System to control reactivity. To verify 'the ability of the Control Rod System to control reactivity.

Specification
Soecification:

A. Reactivity Limitations A. Pleactivity Limetations

1. Reactivity margin - core loading 1. . Reactivity margin - core loading A sufficient number of control rods shall be operable so Sufficient control rods shall be withdrawn following a that the core could be made subcriticat in the most refuelmg' outage when core alterations were performed to reactive conditions during the operating cycle with the demonstrate with a margin of 0.38 percent aldk the core
strongest control rod fully withdrawn and all other can be made suberitical at any time in the subsequent fuel .

4 operable control rods fully inserted. cycle with the analytically determined strongest control l

rod fully withdrawn and all other operable rods fully inserted.

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. Amendment No. MyS*

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3.3.C (cont'd) 4.3.C (cont'd)

2. The average of the scram insertion times for the three 2. At 16-week intervalsi10 percent of the operable control fastest operable control rods of all groups of four control rod drives shall be scram timed above 950 psig. The same l rods in a two-by-two array shall be no greater than: control rod drives should not be tested each interval. I Whenever such scram time measurements are_mede, an -

, Control Rod . Average Scram evaluation shall be made to provide reasonable assurance -

Notch Position Insertion Time that proper control rod drive performance is being Observed (Seconds) maintained.

46 0.361 .

38 0.977 24 2.112 04 3.784

3. The maximum scram insertion time for 90 percent insertion of any operable control rod shall not exceed 3. All control rods shall be determined operable once every .

7.00 sec. 24 months by demonstrating the scram discharge volume drain and vent valves operable when the scram test .

initiated by placing the modo switch in the SHUTDOWN poestion is performed as required by Table 4.1-1 and by-verifying that the drain and vent valves:

.a. Close in less that 30 seconds after receipt of a signal for control rods to scram, and

b. Open when 'the scram signal is reset.

t ' Amendment No. 4F,E 75,.885,1Er85,205 96-

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ATTACHMENT 11 to JPN-95-029 Safety Evaluation For Proposed Changes to Technical Specification Control Rod System Surveillance Test Intervals to Accommodate 24-Month Operatina Cycles (JPTS 95-001El l

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i New York Power Authority JAMES A. FITZPATRICK NUCLEAR POWER PLANT-Docket No. 50-333 DPR 59

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Attachment ll to JPN 95-029 Control Rod System i SAFETY EVALUATION Page 1 of 6 l

1. DESCRIPTION OF THE PROPOSED CHANGES l
1. Page 88, Specification 4.3.A.1, change " strongest operable control rod fully withdrawn" I 1

to " strongest control rod fully withdrawn." The revised specification reads:

1 Sufficient control rods shall be withdrawn following a refueling outage when core alterations were performed to demonstrate with a margin of 0.38 percent Ak/k the core can be made suberitical at any time in the subsequent fuel cycle with the analytically determined strongest control rod fully withdrawn and all other operable rods fully inserted."

2. Page 96,' Specification 4.3.C.2, add the following after the first sentence: "The same control rod drives should not be tested each interval." The revised specification reads:

"At 16 week intervals,10 percent of the operable control rod drives should be scram timed above 950 psig. The same control rod drives should not be tested each interval.

Whenever such scram time measurements are made, an evaluation shall be made to provide reasonable assurance that proper control rod drive performance is being maintained."

3. Page 96, Specification 4.3.C.3, change "each operating cycle" to "every 24 months."

The revised specification reads:

"All control rods shall be determined operable once every 24 months by demonstrating the scram discharge volume drain and vent valves operable when the scram test initiated by placing the mode switch in the SHUTDOWN position is performed as ll. P_URPOSE OF THE PROPOSED CHANGES This application for amendment proposes to extend the control rod system surveillance test intervals to accommodate a 24 month operating cycle. The proposed change in test frequency is every 24 months. These changes are necessary to avoid an extended mid-cycle outage. These changes follow the guidance provided by Generic Letter 91-04, " Changes in Technica' Specification Surveillance Intervals to Accommodate 24 Month Fuel Cycle," (Reference 1). Extension of the surveillance test intervals was evaluated for the FitzPatrick control rod system and the results documented in Reference 2.

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I Attachment 11 to JPN-95-029 Control Rod System SAFETY EVALUATION Page 2 of 6 lit. SAFELY IMPLIOATION OF THE PROPQSED CHANGES The control rod system is the primary A reactivity scram) in order that no fuel damage results from any abnormal operati review of the technical specification required control rod surveillance tests was conducted to determine the safety implications of ext numbers 1 through 3, involves technical clarifications and a surveillance test specification revision.

The technical clarification in Specification 4.3.A.1, Reactivity Umitations, term " operable" from the specification in order to better clarify the analytic determined strongest control rod fully withdrawn f this specification. This is a prudent clarification s with the terminology used in the corresponding lim clarification.

A second technical clarification in Specification 4.3.C.2 Scram insertion Times, provides further information on testing so as to preclude the same c from being tested in subsequent 16 week intervals. This clarification resu indication of the overall control rod drive system operability. No additiona test restrictions or relaxations are created by this clarification.

The current language of Specifications 4.3.A.1 an are required since no operating cycle intervals are the safety implications have been assessed.

Reactivity Margin - Core Loading Test. Soecification 4.3. A.1 This test is performed following a refueling outage when core alterations are performed. The purpose of this test is with f l ycle to demonstrate the analytically with a margi Ak/k that the reactor will be subcritical throughout the ue c determined strongest control rod fully withdrawn and all other rods inserted margin is typically demonstrated by bringing the reactor core to critica free condition, by withdrawing control rods in a normal start-up sequence. T reactivity added to the core to bring the reactor subcriticalis then calcu

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Attachment il to JPN-95-029 Control Rod System SAFETY EVALUATION

- Page 3 of 6 calculated worth of the rods withdrawn must be greater than the worth o' f the strongest rod by 0.38% Ak/k + R. The term R is the difference between the calculated value of maximum core reactivity during the operating cycle and the calculated beginning of:

cycle core reactivity (by definition R ls 10). As such, this ' calculation takes into account the longer fuel cycle. This test is valid for the duration of the fuel cycle. '

Based on the discussion above, the reactivity margin - core loading test can be safely -

extended to accommodate a 24 month operating cycle.

Control Rod Scram Time Test.' Soecification 4.3.C.1

% This test is performed after each refueling outage, where all operable control rods are scram time tested from the fully withdrawn position with the reactor at a pressure

above 950 psig.' This testing is completed prior to exceeding 40% power. .The control rod system is designed to bring the reactor subcritical at a rate fast'enough t'o prevent fuel damage. The design basis transient and accident analyses assume that all of the control rods scram at a specified insertion ratec Surveillance of each individual scram time ensures that the scram time assumed _in the design basis transient and accident -

analysis can be met (i.e., technical specification values are not exceeded). Operating -

experience has shown that control rod scram times do not significantly change over an -

operating cycle. There are additional on-line surveillance tests to. verify control rod operability.. At 16 week intervals,10 percent of the operable control rod drives are i

scram time tested above 950 psig. In addition, accumulator pressure is verified weekly and technical specifications also require testing of control rods if work is performed l which may affect insertion time.

Based on the discussion above, the control rod scram time test can be safely extended l to accommodate a 24 month operating cycle.  !

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Scram Discharoe Instrument Volume (SDM Ver1Ligid Drain Valve Ooerability Test.

. Soecification 4[3.C.3

' This test, performed once each operating cycle, 'demorotrates the scram discharge

. volume vent and drain valves close in less than 30 seconds from the time the reactor 4'

mode switch is placed in shutdown. This test was inco.porated into the Technical Specifications in 1982 to reduce the susceptibility of scram discharge volume systems to common cause failures.' This test is an integrated test of the SDiV drain and vent valves which demonstrates total system performance.' It provides assurance that the:

valves operate automatically to close during a scram to limit the amount of reactor coolant discharged and to open on a scram reset to restore the SDIV system so that there is sufficient volume to accept the reactor coolant discharged during a subsequent scram.

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Attachment'll to JPN-95 029 Control Rod System SAFETY EVALUATION ,

Page.4 of 6 Mechanical functidnality of the system is assured by stroke testing of the valves and verifying valve position and accumulator level and pressure as required by Specifications 4.3.A.2.b and 4.3.A.2.c.;These tests and. verifications are performed while the plant is on-line. Therefore, on line testing provides adequate assurance of -

valve operability.

Functionality of the scram circuitry is ' assured once every three months. The scram circuitry has been previously evaluated for longer cycle length as part of the Reactor.

Protection System Surveillance Test improvements report (Reference 3). Operability of the mode switch and reset relays is demonstrated during forced and planned shutdowns.

A review of recent surveillance tests from 1987 through 1992 indicated that'the acceptance criteria was satisfied.in all cases. However, one instance required additional action where a valve had to be verified open locally and cycled manually, before proper light indication in the control room was observed. -In addition, quarterly on-line testing demonstrates SDIV vent and drain valve operability. Past performance of on-line testing has shown no problematic concerns.

Based on the discussion above, the SDIV and Drain Valve Operability test can be safely extended to accommodate a 24 month operating cycle.=

The assumptions in the Fitzpatrick licensing basis are not invalidated by performing the control rod system surveillances at the bounding interval limits (30 months) to accommodate the 24 month operating cycle.

L IV. EVALUATION OF NO SIGNIFICANT HAZARDS CONSIDERATION Operation of the FitzPatrick plant in accordance with the proposed Amendment would '

i not involve a significant hazards consideration as defined in 10 CFR 50.92, since it would not:

I lL 1. Involve a significant increase in the probability or consequences of an accident

! previously evaluated.

l l- The proposed changes increase the interval between control rod system surveillance -

, tests. These changes are consistent with the guidance provided in Generic Letter 91<

j. 04. These changes do not involve any physical changes to the plant, nor do they alter the way the control rod system functions.~ The type of testing and the corrective actions required if the subject control rod surveillances fail remain the same.. As such, the proposed changes create no new impacts on accidents previously evaluated.

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j Attachment 11 to JPN-95-029 l' s Control Rod System l

SAFETY EVALUATION Page 5 of 6 -

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The reactivity margin - core loading test can be safely extended to accommodate the -

24 month operating cycle. The calculation of reactiiv ty margi n tak esi nto account the longer operating cycle.

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The control rod scram time test can be safely extended to accommodate a 24 month

! operating cycle. Operating experience has indicated that control rod scram times do not significantly change over.an' operating cycle. Additional on-line testing provides 1,. adequate assurance of equipment operabillty.' .

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The SDIV vent and drein valve operability test can be safely extended to accommodate a 24 montn operating cycle. . Evaluation of past surveillance .

performance and additional on-line testing assure valve operability. The operability of .

the mode switch and the reset switch is demonstrated during shutdowns Therefore, the proposed changes do not involve a significant increase in the probability and do not change the consequences of an accident previously evaluated.

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2. create the possibility of a new or different kind of accident from any accident previously evaluated. ,

The proposed changes increase the interval between control rod system surveillance j l

!: tests. These changes are consistent with the guidance provided in Generic Letter 91- 1 L 04. The proposed changes do not change the ability of the control rod system to l provide rapid reactivity control in order that no fuel damage results from any abnormal operating transient. . Past equipment performance and on-line testing indicate the _

i- longer test intervals will not degrade control equipment. No changes are proposed to l the type of testing performed, only to the surveillance interval length. The proposed changes do not modify the design or operation of plant equipment, therefore, no new l I

or different failure modes are introduced.

Therefore, the proposed changes do not create the possibility of a new or different kind ,

of accident from any accident previously evaluated.

3. involve a significant reduction in a margin of safety.

The proposed changes increase the interval between control rod system surveillance tests; These changes are consistent with the guidance provided in Generic Letter 91-

04. The proposed changes do not alter the configuration of the control rod system nor change the manner in which the control rod system functions. : Past equipment .

performance and on-line testing indicate the longer test intervals will not degrade control rod equipment. Operation of the plant remains unchanged by the proposed >

changes.

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Attachment 11 to JPN-95-029 I

! Control Rod System SAFETY EVALUATION .

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! Ther0 fore, the proposed changes do not involve a significant reduction in a margin of safety.

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} V. IMPLEMENTATION OF THE PROPOSED CHANGE _

j. Implementation of the proposed changes will not adversely affect the ALARA or Fire . l j Protection Programs at the FitzPatrick plant, nor will the changes affect the -

j environment. ~

l VI. CONCLUSION 1

I The changes, as proposed, do,not constitute an unreviewed safety question as defined' in 10 CFR 50.59. ' That is, they:

1. will not increase the probability nor the consequences of an accident or malfunction of.

l equipment important to safety as previously evaluated in the Safety Analysis Report; 1

2. will not create the possibility of an accident or. malfunction of a type different from any previously evaluated in the Safety Analysis Report; ,

! 3. will not reduce the margin of safety as defined in the basis for any technical l

speclilcation; and i: 4. Involve no significant hazards consideratidn, as defined in 10 CFR 50.92.

i l Vll. REFERENCES

1. Generic Letter 91-04, " Changes in Technical Specification Surveillance Intervals to Accommodate 24-Month Fuel Cycle," dated April 2,1991.

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2. NYPA Report No. JAF-RPT-CRD-00340, " Control Rod Drive Surveillance Test Extensions," dated November,1991.
3. James A. FitzPatrick - 24 Month Operating Cycle, " Reactor Protection System Surveillance Test improvements," dated February,1991.

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l ATTACHMENT lit to JPN-95-029 I

Markup of the current Technical Specification pages Extension of Control Rod System Surveillance Test Intervals to Accommodate 24-MonttL90eratina Cycles (JPTS-95-001El l

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New York Power Authority JAMES A. FITZPATRICK NUCLEAR POWER PLANT Docket No. 50-333 DPR-59 4

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t i 3s tmuBNG CONDmON FOR OrdRATION 4.3 SURVEldANCE REOLNREMENT ,

4 j 33 REACTMTY CONTROL 4.3 REACTMTY CONTROL

! Appucabstr. Appscabstr. -

)j Appues to the operamonal status of the Contrd Rod System. AppEse to the surveRance requiremerte W the Conkd Rod System.

Objecthe:

l Objecove:

l To aneure the abaty W Ihe Cortrd Rod System to conkel reactMty. To verNy the abWty W the Cored Rod System to conkd reactMty. l 1

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W Speciscamon:

j A. ReactMty Umkadone A. ReactMty Umkations t

! 1. ReedMty margin-coreloading 1. ReactMty margin-coreloading l l

A sulReient number of control rods sheE be operable so SulEcient contrd rods shen be withdrawn fonowin0 a j

that the core could be made subcridcid in the most refueEng outage when core aNorations were performed to l reactive constions durin0 the operating cycle wth the demonstrate wilh a margin of 0.38 percent ak/k the core skongest control rod fully withdrawn and aE other operable can be made subcridcol at any time in the m W M fuel

! contrd rods tuuyinserted. cyde~wth the analyuce8y determined skongest(operame i control rod fugywthdrawn and at other operable rods fuBy

1,-

inserted. .

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j Amendment No. 155 as Y .

Q %d -

a JAFNPP

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3.3.C {cdnt'd) 4.3.C Icont'd)

2. The average of the scram insertion times for the three 2. At 16-week intervals,10 percent of the operable control fastest operable control rods of all groups of four control. rod drives shaN be scram timed above 950 psig. <

rods in a two-by-two array shnu be no greater than: Whenever such scram time measurements are made, an evaluation shall be made to provide reasonable assurance Controt Rod Average Scram that proper control rod drive performance is being Notch Eseition Insertion Time maintained.

Observ2n D conds) 7%e si7me dh,'m' drlyes dould IMt be 46 0.361 ## O!* ~

. 38 0.977 24 2.112 6 04 3.764 eve.ry 24 mon 4hs

3. The maximum scram insertion time for 90 perce 3. All control rods shall be determined operable once eseh-insertion of any operable control rod shall not exceed  :;::2. ,1 by demonstrating the scram discharge 7.00 sec. l volume drain and vent valves operable when the scram test initiated by placing the mode switch in the SHUTDOWN position is performed as required by Table 4.1-1 and by verifying that the drain and vent valves:
a. Close in less that 30 seconds after receipt of a segnal for control rods to scram, and -i
b. Open when the scram signal is reset. l' t

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Amendment No. 4 f Id

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