Text

Proposed TS Allowing Plant Personnel to Effect Repairs to Rod Control Sys in an Orderly Manner While Continuing to Ensure That Control & Shutdown Banks Capable of Performing Safety Function as Designed
	ML20035A355
Person / Time
Site:	North Anna
Issue date:	03/18/1993
From:	; VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	;
Shared Package
ML20035A350	List: ML20035A349; ML20035A355;
References
	NUDOCS 9303250188
	Download: ML20035A355 (17)
	v • d • e

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i Technical Specifications Changes i

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1 9303250188 930318 PDR ADOCK 05000338 i

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e REACTMTVCONTROL SYSTEMS 3/4.1.3 MOVABLE CONTROL ASSEMBLIES GROUP HEIGHT UMITING CONDITION FOR OPERATION 3.1.3.1 All shutdown and control rods shall be OPERABLE and positioned within 112 steps

of their group step counter demand position.

APPLICABILITY: MODES 1" and 2".

ACTION:

a. With one or more rods untrippable, determine within one hour that the SHUTDOWN l

MARGIN requirement of Specification 3.1.1.1 is satisfied and be in HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

b. With more than one rod misaligned from the group step counter demand position by l

more than the above alignment requirements, determine within one hour that the SHUTDOWN MARGIN requirement of Specification 3.1.1.1 is satisfied and be in HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

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With a maximum of one rod misaligned from the group step counter demand position l_

by more than the above alignment requirements, POWER OPERATION may continue provided that within one hour, either:

1. The rod is restored to OPERABLE status within the above alignment requirements, or

2. The rod is declared inoperable and the SHUTDOWN MARGIN requirement of Specification 3.1.1.1 is satisfied. POWER OPERATION may then continue provided that:

I a) A reevaluation of each accident analysis of Table 3.1-1 is performed within 5 days. This reevaluation shall confirm that the previous analyzed results of these accidents remain valid for the duration of operation under these conditions, and For power levels below 50% of RATED THERMAL POWER, the position of each rod as determined by its individual rod position indicator may be more than 1 12 steps from its group step counter demand position for a maximum of one hour in every 24. During this hour, the indicated position of each rod may be no more than 24 steps from its demand position. The 124 step / hour limit is not applicable when control rod position is known to j

be greater than 12 steps from the rod group step counter demand position indicat'on.

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See Special-Test Exceptions 3.10.2 and 3.10.3.

NORTH ANNA - UNIT 1 3/4 1-18 Amendment No.-%,438,

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BE6CTMTYCONTROL SYSTBAS SHUTDOWN ROD INSERTION LIMIT i

UMITING CONDITION FOR OPERATION 3.1.3.5 All shutdown rods shall be limited in physical insertion as specified in the CORE OPERATING UMITS REPORT.

i APPLICABILITY: MODES 1* and 2*#.

i ACTION:

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a. With a maximum of one shutdown rod inserted beyond the insertien limit specified in l

the CORE OPERATING LIMITS REPORT, except for surveillance testing pursuant to Specification 4.1.3.1.2, within one hour either:

1. Restore the rod to within the insertion limit specified in the CORE OPERATING

.l LIMITS REPORT, or

2. Declare the rod to be misaligned and apply Specification 3.1.3.1 l

b. With a maximum of one shutdown bank inserted beyond the insertion limit specified in the CORE OPERATING LIMITS REPORT during surveillance testing pursuant to Specification 4.1.3.1.2 and immovable due to malfunctions in the rod control system, POWER OPERATION may continue provided that:

1. the shutdown bank is inserted no more than 18 steps below the insertion limit as j

measured by the group step counter demand position indicators,

2. the affected bank is trippable, l

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3. each shutdown and control rod is aligned to within 12 steps of its respective group step counter demand position, g

4. the insertion limits of Specification 3.1.3.6 are met for each control bank,

5. the SHUTDOWN MARGIN requirement of Specification 3.1.1.1 is determined to be met at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , and

6. the shutdown bank is restored to within the insertion limit specified in the CORE j

OPERATING LIMITS REPORT within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .

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Otherwise, be in HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

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See Special Test Exceptions 3.10.2 and 3.10.3.

With Kelf 21.0 J

NORTH ANNA-UNIT 1 3/4 1-24 Amendment No.-438, -446, I

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I SURVEll1ANCE REQUIREMENTS 4.1.3.5 Each shutdown rod shall be determined to be within the insertion limit specified in the CORE OPERATING UMITS REPORT

a. Within 15 minutes prior to initial control rod bank withdrawal during an approach to reactor criticality, and l

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b. At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter.

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NORTH ANNA - UNIT 1 3/4 24a Amendment No.

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REACTMTVCOfffROL SYST9AS CONTROL RODINSERTION LIMITS UMITING CONDITION FOR OPERATION 3.1.3.6 The control banks shall be limited in physical insertion as specified in the CORE OPERATING UMITS REPORT.

APPLICABILITY: MODES 1* and 2*#.

i ACTION

a. With the control banks inserted beyond the insertion limits, except for survei! lance l

testing pursuant to Specification 4.1.3.1.2, either:

1. Restore the control banks to within the insertion limits within two hours, or l

2. Reduce THERMAL POWER within two hours to less than or equal to that fraction of

.l RATED THERMAL POWER which is E! lowed by the rod group step counter demand i

position using the insertion limits specified in the CORE OPERATING LIMITS REPORT, or

3. Be in HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

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b. With a maximum of one control bank inserted beyond the insertion limit specified in the CORE OPERATING LIMITS REPORT during surveillance testing pursuant to j

Specification 4.1.3.1.2 and immovable due to malfunctions in the rod control system, POWER OPERATION ##may continue provided that I

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1. the control bank is inserted no more than 18 steps below the insertion limit as i

measured by the group step counter demand position indicators,

2. the affected bank is trippable, j

3. each shutdown and control rod is aligned to within 12 steps of its respective l

groco step counter demand position,

4. the insertion limits of Specification 3.1.3.5 are met for each shutdown bank, I

i See Special Test Exceptions 3.10.2 and 3.10.3.

With Keff 21.0.

1. Provision for continued POWER OPERATION does not apply to Control Bank D inserted beyond the insertion limit.

NORTH ANNA-UNIT 1 3/4 1-25 Amendment NoA38, 446, i

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UMITING CONDITION FOR OPERATION (cont'd.)

5. the SHUTDOWN MARGiti requiremont of Specification 3.1.1.1 is determined to be i

met at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , and

6. the control bank is restored to within the insertion limit specified in the CORE OPERATING LIMITS REPORT within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .

Otherwise, be in HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

SURVE!LLANCE REQUIREMENTS 4.1.3.6 The position of each control bank shall be determined to be within the insertion limits at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months except during time intervals when the Rod insertion Limit Monitor is inoperable, then verify either the individual rod positions (indicated positions) or the group step counter demand position of each rod group to be within the insertion limits at least once per 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .

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l NORTH ANNA-UNIT 1 3/4 1-25a Amendment No.

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PEACTMTY CONTROL SYSTEMS i

BASESJContinued) i The ACTION statements which permit limited variations from the basic requirements are accompanied by additional restrictions which ensure that the original design criteria are met.

Misalignment of a rod requires measurement of peaking factors or a restriction in THERMAL.

POWER: either of these restrictions provides assurance of fuel rod integrity during continued operation. In addition those accident analyses affected by a misaligned rod are reevaluated to confirm that the results remain valid during future operation.

Continuous monitoring of rod position with respect to insertion limits and rod deviation is provided by the rod insertion limit monitor and rod position deviation monitor, respectively.

OPERABILITY of the rod position deviation monitor is verified by a functional test at least once per 7 days and by comparison of the indicated positions versus the respective demand position indicators at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . If the rod position deviation monitor or the rod insertion limit monitor is inoperable, the frequency of manual comparison of indicated rod (or bank) position is increased to an interval of at least once per 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .

In the event that a malfunction of the Rod Control System renders control rods immovable, provision is made for continued operation provided:

the affected control rods remain trippable, and i

the individual control rod alignment limits are met.

In the event that a malfunction of the Rod Control System renders control rod banks immovable during surveillance testing, provision is made for 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months of continued operation provided:

the affected control rod banks remain trippable, the individual control rod alignment limits are met, a maximum of one control or shutdown bank is inserted no more than 18 steps below the insertion limit, and the SHUTDOWN MARGIN requirements are verified every 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months during the period the insertion limit is not met.

Control Bank D is excluded from the 72 hour8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months provision since insertion of D Bank below the insertion limit is not required for control rod assembly surveillance testing.

Checks are performed for each reload core to ensure that bank insertions of up to 18 mil not result in power distributions which violate the DNB criterion for ANS Condition I.

Jents ( moderate frequency transients analyzed in Section 15.2 of the UFSAR) or in a j

violation of the SHUTDOWN MARGIN requirement of Specification 3.1.1.1 during the repair period.

l The 72 hour8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months period for a, control rod assembly bank to be inserted below its insertion limit restricts the likelihood of a more severe (i.e., ANS Condition lli or IV) accident or transient condition occurring concurrently with the insertion limit violation.

used in the accident analyses. Measurement with Tavg 2 500*F-and with all reactor coolant ~

The maximum rod drop time restridion is consistent with the assumed rod drop time j

pumps operating ensures that the measured drop times will be representative of insertion times experienced during a reactor trip at operating conditions.

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NORTH ANNA - UNIT 1 B 3/4 1-4a Amendment NoA38, l

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I REACTMTYCONTROL SYSTEMS f

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3/4.1.3 MOVABLE CONTROL ASSEMBLIES GROUP HEIGHT LIMITING CONDITION FOR OPERATION 3.1.3.1 All shutdown and control rods shall be OPERABLE and positioned within i 12 steps

of their group step counter demand position.

l APPLICABILITY: MODES 1" and 2".

t ACT!ON:

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a. With one or more rods untrippable, determine within one hour that the SHUTDOWN l

c MARGIN requirement of Specification 3.1.1.1 is satisfied and be in HOT STANDBY within G hours.

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b. With more than one rod misaligned from the group step counter demand position by l

l more than the above alignment requirements, determine within one hour that the l

SHUTDOWN MARGIN requirement of Specification 3.1.1.1 is satisfied and be in HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

c.

With a maximum of one rod misaligned from the group step counter demand position l

by more than the above alignment requirements, POWER OPERATION may continue provided that within one hour, either.

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1. Toe rod is restored to OPERABLE status within the above alignment requirements, or r

2. The rod is declared inoperable and the SHUTDOWN MARGIN requirement of Specification 3.1.1.1 is satisfied.

POWER OPERATION may then continue provided that:

a) A reevaluation of each accident analysis of Table 3.1-1 is performed within 5 days. This reevaluation shall confirm that the previous analyzed results of j

these accidents remain valid for the duration of operation under these conditions, and I

l For power levels below 50% of RATED THERMAL POWER, the position of each rod as determined by its individual rod position indicator may be more than i 2 steps from its 1

group step counter demand

position for a rnaximum of one hour in every 24. During this hour, the indicated position of each rod may be no more than i 24 steps from its demand position. The 124 step / hour limit is not applicable when control rod position is known to be greater than 12 steps from the rod group step counter demand position indication.

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See Special Test Exceptions 3.10.2 and 3.10.3.

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NORTH ANNA - UNIT 2 3/4 1 16 Amendment NoA24, l

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i REACTMTYCONTROLSYSTEMS i

SHUTDOWN ROD INSERTION UMIT i

UMITING CONDITION FOR OPERATION l

3.1.3.5 All shutdown rods shall be limited in physical insertion as specified in the CORE OPERATING UMITS REPORT.

APPUCABluTY: MODES 1* and 2*#.

i ACTX)N

a. With a maximum of one shutdown rod inserted beyond the insertion limit specified in l

the CORE OPERATING UMITS REPORT, except for surveillance testing pursuant to Specification 4.1.3.1.2, within one hour either

1. Restore the rod to within the insertion limit specified in the CORE OPERATING l

i UMITS REPORT, or

2. Declare the rod to be misaligned and apply Specification 3.1.3.1 l

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b. With a maximum of one shutdown bank inserted beyond the insertion limit specified in the CORE OPERATING LIMITS REPORT during surveillance testing pursuant to i

Specification 4.1.3.1.2 and immovable due to malfunctions in the rod control system, POWER OPERATION may continue provided that:

1. the shutdown bank is inserted no more than 18 steps below the insertion limit as I.leasured by the group step counter dema'd position indicators,

2. the affected bank is trippable,

3. each shutdown and control rod is aligned to within 3.12 steps of its respective group step counter demand position,

4. the insertion limits of Specification 3.1.3.6 are met for each control bank, l

S. the SHUTDOWN MARGIN requirement of Specification 3.1.1.1 is determined to be met at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , and

6. the shutdown bank is restored to within the insertion limit specified in the CORE OPERATING LIMITS REPORT within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .

Otherwise, be in HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

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See Special Test Exceptions 3.10.2 and 3.10.3.

With Kett greater than or equal to 1.0 i

NORTH ANNA - UNIT 2 3/4 1-22 Amendment NoA27,4GO, f

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l SURVElllANCE REOU!REMENTS 4.1.3.5 Each shutdown rod shall be determined to be within the insertion limit specified in the.

CORE OPERATING UMITS REPORT

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a. Within 15 minutes prior to initial control rod bank withdrawal during an approach' to reactor criticality, and l

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b. At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter.

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l NORTH ANNA-UNIT 2 3/4 1 22a Amendment No.

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REACTMTYOONTROL SYSTEMS

_ CONTROL RODINSERTION LIMITS UMITING CONDITION FOR OPERATION 3.1.3.6 The control banks shall be limited in physical insertion as specified in the CORE OPERATING UMITS REPORT.

APPLICABILITY: MODES 1* and 2*#.

i ACTION

a. With the control banks inserted beyond the insertion limits, except for surveillance l

testing pursuant to Specification 4.1.3.1.2, either:

1. Restore the control banks to within the insertion limits within two hours, or l

2. Reduce THERMAL POWER within two hours to less than or equal to that fraction of

,l RATED THERMAL POWER which is allowed by the rod group step counter demand position using the insertion limits specified in the CORE OPERATING LIMITS REPORT,or

3. Be in HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

b. With a maximum of one control bank inserted beyond the insertion limit specified in f

the CORE OPERATING LIMITS REPORT during surveillance testing pursuant to Specification 4.1.3.1.2 and immovable due to malfunctions in the rod control system, POWER OPERATION ##may continue provided that:

1. the control bank is inserted no more than 18 steps below the insertion limit as measured by the group step counter demand position indicators,

2. the affected bank is trippable.

3. each shutdown and control rod is aligned to within 1 12 steps of its respective group step counter demand position,

4. the insertion limits of Specification 3.1.3.5 are met for each shutdown bank, I

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See Special Test Exceptions 3.10.2 and 3.10.3.

With Keft 21.0.

1. Provision for continued POWER OPERATION does not apply to Control Bank D inserted beyond the insertion limit.

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NORTH ANNA - UNIT 2 3/4 1-23 Amendment NoA24, -430, 1

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UMITING CONDITION FOR OPERATION (cont'd.)

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5. the SHUTDOWN MARGIN requirement of Specification 3.1.1.1 is determined to be met at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , and i

6. the control bank is restored to within the insertion limit specified in the CORE j

OPERATING UMITS REPORT within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .

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Otherwise, be in HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

i SURVEILLANCE REQUIREMENTS l

4.1.3.6 The position of each control bank shall be determined to be within the insertion limits at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months except during time intervals when the Rod insertion Umit Monitor is inoperable, then verify either the Individual rod positions (indicated positions) or the group i

step counter demand position of each rod group to be within the insertion limits at least once per 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .

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NORTH ANNA - UNIT 2 3/4 1-23a Amendment No.

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i PEACTMTYCONTROL SYST9AS 3

BASES (Continued) i T

The ACTION statements which permit limited variations from the basic requirements are accompanied by additional restrictions which ensure that the original design criteria are met.

Misalignment of a rod requires measurement of peaking factors or a restriction in THERMAL i

POWER: either of these restrictions provides assurance of fuel rod integrity during continued operation. In addition those accident analyses affected by a misaligned rod are reevaluated to

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confirm that the results remain valid during future operation.

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Continuous monitoring of rod position with respect to insertion limits and rod deviation is provided by the rod insertion limit monitor and rod position deviation monitor, respectively.

t OPERABILITY of the rod position deviation monitor is verified by a functional test at least once per 7 days and by comparison of the indicated positions versus the respective demand position indicators at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . If the rod position deviation monitor or the rod insertion limit monitor is inoperable, the frequency of manual comparison of indicated rod (or bank) j position is increased to an interval of at least once per 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .

in the event that a malfunction of the Rod Control System renders control rods immovable, provision is made for continued operation provided:

the affected control rods remain trippable, and the individual control rod alignment limits are met.

in the event that a malfunction of the Rod Control System renders control rod banks immovable during surveillance testing, provision is made for 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months of continued operation

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provided:

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the affected control rod banks remain trippable, the individual control rod alignment limits are met.

a maximum of one control or shutdown bank is inserted no more than 18 steps below the insertion limit, and I

the SHUTDOWN MARGIN requirements are verified every 12. hours during the period j

the insertion limit is not met.

Control Bank D is excluded from the 72 hour8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months provision since insertion of D Bank below the insertion limit is not required for control rod assembly surveillance testing.

Checks are performed for each reload core to ensure that bank insertions of up to 18 i

steps will not result in power distributions which violate the DNB criterion for ANS Condition 11 transients ( moc'erate frequency transients analyzed in Section 15.2 of the UFSAR) or in a violation of the SHUTDOWN MARGIN requirement of Specification 3.1.1.1 during the repair

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period.

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i The 72 hour8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months period for a, control rod assembly bank to be inserted below its insertion limit restricts the likelihood of a more severe (i.e., ANS Condition ill or IV) accident or transient condition occurring concurrently with the insertion limit violation.

The maximum rod drop time restriction is consistent with the assumed rod drop time used in the accident analyses. Measurement with Tavg 2 500*F and with all reactor coolant pumps operating ensures that the measured drop times will be representative of insertion times experienced during a reactor trip at operating conditions.

NORTH ANNA - UNIT 2 B 3/4 1 -4 a Amendment NoAG4,

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l Significant Hazards Consideration I

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SIGNIFICANT HAZARDS CONSIDERATION Virginia Electric and Power Company has proposed changes to the North Anna Power Station Units 1 and 2 Technical Specifications which provide for operation with one or more aligned and trippable control or shutdown banks which cannot be moved by the Rod Control i

system.

In addition, provision is made for li.mited operation with a

bank below its insertion limit under certain restricted conditions.

It has been determined that the proposed changes do involve a significant hazards consideration as defined in 10 not i

CFR 50.92.

The basis for this determination may be stated as follows:

1.

The proposed changes will not involve a significant increase in either the probability of occurrence or potential consequences of an accident previously i

evaluated in the UFEAR. Allowing for continued operation j

during diagnosis and repair associated with electronic or 1

electrical mz.1 functions of the Rod Control System is I

acceptable, since the design safety function of the I

control rods (reactor trip) will remain unaffected during the repair period.

During the extended troubleshooting and maintenance period, the requirements for control rod alignment, insertion limits (except~

for a

small allowed deviation for one bank) and shutdown margin will r

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j be maintained.

The small deviation from the control rod insertion limits allowed for one bank for up to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months 1

will not adversely impact the current Technical i

I Specification requirements for normal operation core power distributions.

The proposed changes do not affect the ability of the control rods to perform their intended safety function when a safety system. setting is l

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reached.

Nor will any new or unique accident precurscrs l

i be introduced by the proposed changes.

Therefore the probability and consequences of accidents related to or i

dependent on control rod operation will remain 5

unaffected.

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The proposed change will result in a small increase in the probability that, at any given time, a control or 1

i shutdown bank will be inserted slightly below (i.e. up to 18 steps) its insertion limit. However, by design, the control and shutdown banks will continue to meet the s

safety analysis criterion for steady state and ANS Condition II (moderate frequency) transients.

The i

allowed insertion is not a malfunction of equipment i,

d' important to safety in this case and 'therefore the probability of such a malfunction is not iricreased.

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2.

The proposed changes will not create the possibility of I

a new or different kind of acc3 h ' Crom any previously I

evaluated.

There are no new faiJ..

? des or mechanisms e

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f associated with plant operation for an extended period to e

perform maintenance on the Rod Control System.

I Limited periods of operation with immovable but trippable control rods does not involve any modification to the operational limits or physical design of the involved i

systems.

There are no new accident precursors created i

due to the allowed maintenance period.

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The results of the current accident analyses are not impacted by this change. Therefore the margin of safety i

is not impacted.

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ML20035A355

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