ML20217E901

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Proposed Tech Specs Re Configuration Risk Mgt Program for risk-informed Allowed Outage Times & Insp Frequency of EDGs
ML20217E901
Person / Time
Site: North Anna  Dominion icon.png
Issue date: 03/25/1998
From:
VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
Shared Package
ML20217E897 List:
References
NUDOCS 9803310201
Download: ML20217E901 (13)
v • d • e


Text

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3/.Lg FIECTRICAL POWER SYSTEMS 3/4.8.1. A.C. SOURCES OPERATING LIMITING CONDITION FOR OPERATION 3.8.1.1 As a minimum, the following A.C. electrical power sources shall be OPERABLE:

a. Two physically independent circuits between the offsite transmission network and the onsite Class IE distribution system, and
b. Two separate and independent emergency diesel generators (EDGs): l
1. Each with a separate day tank containing a minimum of 450 gallons of fuel, and
2. A fuel storage system consisting of two underground storage tanks each containing a minimum of 45,000 gallons of fuel (This is a shared system with Unit 2), and
3. A separate fuel transfer system.

APPLICABII ITY: MODES 1,2,3 and 4 ACTION:

a. With one offsite circuit of 3.8.1.1.a inoperable, demonstrate the OPERABILITY of the remaining A.C. sources by performing Surveillance Requirement 4.8.1.1.1.a within I hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter. Restore the offsite circuit to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />,
b. (Risk-Informed) With one EDG ( f 3.8.1.1.b inoperable, demonstrate the l OPERABILITY of the offsite A.C. power sources by performing Surveillance Requirement 4.8.1.1.1.a within I hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter. If the EDG is inoperable due to any cause other than an inoperable support system, an l independently testable component, or preplanned preventive maintenance or testing, demonstrate the OPERABILITY of the remaining OPERABLE EDG by performing Surveillance Requirement 4.8.1.1.2.a.4 within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> *, unless the

. absence of any potential common mode failure for the remaining EDG is demonstrated. Restore the EDG to OPERABLE status within 14 days if the AAC DG and the opposite unit's EDGs are OPERABLE or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. In addition:

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' NORTH ANNA -. UNIT 1 3/48-1 AT.end=n* R. 83,128,181,203 j 9803310201 900325 I j

PDR. ADOCK 05000338 '

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. . - .7 RI FCTRICAL POWER SYSTEMS 1

SURVEILLANCE REQUIREMENTS - 4.8.1.1.2 (Continued)

7. Verifying that the auto-connected loads to each EDG do not exceed the l 2000 hour0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> rating of 3000 kw.
8. Verifying the EDG's capability to:

a) Synchronize with the offsite power source while the EDG is loaded with its emergency loads upon a' simulated restoration of offsite power, b) Transfer its loads to the offsite power source, and c) Proceed through its shutdown sequence.

9. Verifying that the following EDG lockout features prevent EDG starting l only when required:

a) Remote Local Selection Switch b) Emergency Stop Switch'

10. Verifying the EDG's hot restart capability by:

a) Operating the EDG** loaded to an indicated 2500 to 2600 kw*** for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> or until operating temperatures have stabilized, and b) Within 5 minutes of shutdown verify the EDG can be started ** and l accelerated to at least 900 rpm in less than or equal to 10 seconds. The generator voltage and frequency shall be 4160

  • 420 volts and 60
  • 1.2 Hz within 10 seconds after the start signal.
e. At least once per 10 years or after any modifications which could affect EDG interdependence by starting ** both EDGs simultaneously, during shutdown, and verifying that both EDGs accelerate to at least 900 rpm in less than or equal to 10 seconds.
f. At least once per 24 months during any mode of operation, by subjecting each EDG to a preventive maintenance inspection in accordance with maintenance procedures appropriate for diesels used for this class of standby service.

" This test shall be conducted in accordance with the manufacturer's recommendations regarding engine prelube and warmup procedures, and as applicable regarding loading

< recommendations.

  • * * : This band is meant as guidance to avoid routine overloading of the engine. Loads in excess

. of this band for special testing under direct monitoring of the manufacturer or momentary

. variations due to changing bus loads'shall not invalidate the test.

NORTH ANNA - UNIT 1 3/4 8-3c Amendment No. 83, l'5, !S A, I

1 - c.

314 1 ELECTRICAL POWER SYSTEMS BASES 3/4.8.1 and 3/4.8.2 A.C. and D.C. POWER SOURCES AND DISTRIBUTION

' The OPERABILITY of the A.C. and D.C. power sources and associated distribution-systems during operation ensures that sufficient power will be available to supply the safety related equipment required for 1) the safe shutdown of the facility and 2) the mitigation and control of accident conditions within the facility. The minimum specified independent and redundant A.C.

and D.C. power sources and distribution systems satisfy the requirements of General Design-Criteria 17 of Appendix "A" to 10 CFR 50.

For each EDG, the fuel oil transfer system shall be capable of automatically transferring fuel oil to the associated EDG day tank in sufficient quantities to maintain adequate day tank level to support fullload operation of the EDG.

The ACTION requirements specified for the levels of degradation of the power sources provide restriction upon continued facility operation commensurate with the level of degradation.

The OPERABILITY of the power sources are consistent with the initial condition assumptions of the accident analyses and are based upon maintaining at least one of each of the onsite A.C. and D.C. power sources and associated distribution systems OPERABLE during accident conditions coincident with an assumed loss of offsite power and single failure of the other onsite A.C. source.

Entering the 14 day EDG action statement during power operation has been shown to result in a small increase in the core damage frequency, provided the Alternate A.C. diesel generator (AAC DG) is OPERABLE and the opposite unit's EDGs are both OPERABLE. A Configuration Risk Management Program (CRMP) defined in Administrative Control Section 6.8.4.g is implemented to evaluate risk associated with the EDG outage. The EDG and AAC DG annual unavailability is limited by the Maintenance Rule Program.

When one or more of the diesel generators (i.e., AAC DG or opposite unit's EDGs) required to enter the 14 day action statement is inoperable or becomes inoperable during the fourteen day action statement of the affected EDO, a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> action statement is entered. If the three diesel generators (i.e., AAC DG or the opposite unit's EDGs) required to support entry into the fourteen day action statement are restored to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, the remainder of the 14 day action statement can be used. Restoring the affected EDG to service removes the conditional OPERABILITY requirements for the AAC DG and opposite unit's EDGs.

NORTH' ANNA - UNIT 1 B 3/4 8-l' Amendment No. 33,97,156,303

u.. 1 ADMINISTRATIVE CONTROLS -

L 8)- Limitations on the annual and quarterly air doses resulting from noble gases released in gaseous effluents from each unit to areas beyond the SITE BOUNDARY conforming to Appendix I to 10 CFR Part 50,

9) Limitations on the annual and quarterly doses to a MEMBER OF THE PUBLIC from Iodine-131, Iodine-133, tritium, and all radionuclides in particulate form with half-lives greater than 8 days in gaseous effluents released from each unit to areas beyond the SITE BOUNDARY conforming to Appendix I to 10 CFR 50,
10) Limitations on the annual dose or dose commitment to any MEMBER OF THE PUBLIC due to releases of radioactivity and to radiation from uranium fuel cycle sources conforming to 40 CFR Part 190.

L Rndiological Environmental Monitoring Program A program shall be provided to monitor the radiation and radio nuclides in the environs of the plant. The program shall provide (1) representative measurements of radioactivity in the highest potential exposure pathways, and (2) verification of the accuracy of the effluent monitoring program and modeling of environmental exposure pathways. The program shall (1) be contained in the ODCM, (2) conform to the guidance of Appendix I to 10 CFR Part 50, and (3) include the following:

1) Monitoring, sampling, analysis, and reporting of radiation and radionuclides in the environment in accordance with the methodology and parameters in the ODCM,
2) A Land Use Census to ensure that changes in the use of areas at and beyond the SITE BOUNDARY are identified and that modifications to the monitoring program are made if required by the results of this census, and
3) Participation in a Interlaboratory Comparison Program to ensure that independent checks on the precision and accuracy of the measurements of radioactive materials in environmental sample matrices are performed as part of the quality assurance program for environmental monitoring,
g. Configuration Risk Management Program The Configuration Risk Management Program (CRMP) provides a proceduralized risk-informed assessment to manage the risk associated with equipment inoperability. The program applies to technical specification structures, systems, or components for which a risk-informed allowed outage time has been granted. The program shall include the following elements:
1) Provisions for th 1 ontrol and implementation of a Level 1, at power, internal events, PRA-informed methodology. The assessment shall be capable of evaluating the applicable plant configuration.
2) Provisions for performing an assessment prior to entering the LCO Action Statement for planned activities, NORTH ANNA - UNIT 1 .6-13c. Amendment No. 4-30, j

ADMINISTRATIVE CONTROLS 3 Configuration Risk Management Program (continued)

3) Provisicns for performing an assessment after entering the LCO Action Statement for unplanned entry into the LCO Action Statement.
4) Provisions for assessing the need for additional actions after the discovery of additional equipment out of service conditions while in the LCO Action Statement.
5) Provisions for considering other applicable risk significant contributors such as Level 2 issue and external events, qualitatively or quantitatively.

Current risk-informed action statements include: Action 3.8.1.1.b (d REPORTING REOUIREMENTS ROUTINE REPORTS 6.9.1 In addition to the applicable reporting requirements of Title 10, Code of Federal Regulations, the following reports shall be submitted to the Director of the Regional Office of Inspection and Enforcement unless otherwise noted.

STARTUP REPORTS 6.9.1.1 A summary report of plant startup and power escalation testing shall be submitted following (a) receipt of an operating license, (2) amendment to the license involving a planned increase in power level, (3) installation of fuel that has a different design or has been manufactured by a different fuel supplier, and (4) modifications that may have significantly altered the nuclear, thermal, or hydraulic performance of the plant.

6.9.1.2 The startup report shall address each of the tests identified in the FSAR and shall include a description of the measured values of the operating conditions or characteristics obtained during the test program and a comparison of these values with design predictions and specifications. Any corrective actions that were required to obtain satisfactory operation shall also be described. Any additional specific details requested in h3ense conditions based on other commitments shall be included in this report.

6.9.1.3 Startup reports shall be submitted within (1) 90 days following completion of the startup test program, (2) 90 days following resumption or commencement of commercial power operation, or (3) 9 months following initial criticality, whichever is earliest. If the Startup Report does not cover all three events (i.e., initial criticality, completion of startup test program, and resumption or commencement of commercial power operation), supplementary reports shall be submitted at least every three months until all three events have been con $leted.

i NORTH ANNA-UNIT 1 6-14 Amendment No. 63 i

FIFCTRICAL POWER SYSTEMS

., 3/31 3/4.8.1 A.C. SOURCES OPERATING LIMITING CONDITION FOR OPERATION -

-3.8.1.1 As a minimum, the following A.C. electried power sources shall be OPERABLE:

a. Two physically independent circuits between the offsite transmission network and the onsite Class lE distribution system, and
b. Two separate and independent emergency diesel generators (EDGs): l
1. Each with a separate day tank containing a minimum of 450 gallons of fuel, and
2. A fuel storage system consisting of two underground storage tanks each containing a minimum of 45,000 gallons of fuel (This is a shared system with Unit 1), and
3. A separate fuel transfer system.

APPLICABILITY: MODES 1,2,3 and 4.

ACTION:

a. With one offsite circuit of 3.8.1.1.a inoperable, demonstrate the OPERABILITY of the remaining A.C. sources by perfonning Surveillance Requirement 4.8.1.1.1.a within I hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter. Restore the offsite circuit to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />,
b. (Risk-Informed) With one EDG of 3.8.1.1.b inoperable, demonstrate the l OPERABILITY of the offsite A.C. power sources by performing Surveillance Requirement 4.8.1.1.1.a within I hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter. If the EDG is inoperable due to any cause other than an inoperable support system, an l independently testable component, or preplanned preventive maintenance or testing, demonstrate the OPERABILITY of the remaining OPERABLE EDG by performing Surveillance Requirement 4.8.1.1.2.a.4 within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> *, unless the j absence of any potential common mode failure for the remaining EDG is demonstrated. Restore the EDG to OPERABLE status within 14 days if the AAC I

DG and the opposite unit's EDGs are OPERABLE or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. In addition:

  • This action is required to be completed regardless of when the inoperable EDG is

. restored to OPERABILITY l

' NORTH ANNA - UNIT 2. 3/48-1 Amendment No. d',  ! !2,165, i 303 i

_a

+

ELECTRICAL POWER SYSTEMS SURVEILLANCE REQUIREMENTS - 4.8.1.1.2 (Continued)

9. _ Verifying that the following EDG lockout features prevent EDG starting l only when required:

a) Remote Local Selection Switch b) Emergency Stop Switch

10. Verifying the EDG's hot restart capability by:

a) Operating the EDG** loaded to an indicated 2500 to 2600 kw*** for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> or until operating temperatures have stabilized, and b) Within 5 minutes of shutdown verify the EDG can be started ** and l accelerated to at least 900 rpm in less than or equal to 10 seconds. The generator voltage and frequency shall be 4160

  • 420 volts and 60 1.2 Hz within 10 seconds after the start signal,
e. At least once per 10 years or after any modifications which could affect EDG interdependence by starting ** both EDGs simultaneously, during shutdown, and verifying that both EDGs accelerate to at least 900 rpm in less than or equal to 10 seconds.
f. At least once per 24 months during any mode of operation, by subjecting each EDG to a preventive maintenance inspection in accordance with maintenance procedures appropriate for diesels used for this class of standby service.

4.8.1.1.3 Each emergency diesel generator 125-volt battery bank and charger shall be demonstrated OPERABLE:

a. At least once per 7 days by verifying that:
1. The parameters in Table 4.8-3 meet Category A limits and
2. The total battery terminal voltage is 2129 volts on a float charge.
    • ' This test shall be conducted in accordance with the manufacturer's recommendations regarding engine prelube and warmup procedures, and as applicable regarding loading recommendations.

L*" This band is meant as guidance to avoid routine overloading of the engine. Loads in excess of this band for special testing under direct monitoring of the~ manufacturer or momentary variations due to changing bus loads shall not invalidate the test.

iNORTH ANNA - UNIT 2 3/48 Amendment No. 48, Si,165,

l 3/g FI FCTRICAL POWER SYSTEMS BASES-3/4.8.1 and 3/4.8.2 A.C. and D.C. POWER SOURCES AND DISTRIBUTION The OPERABILITY of the A.C. and D.C. power sources and associated distribution -

- systems during operation ensures that sufficient power will be available to supply the safety related equipment required for 1) the safe shutdown of the facility and 2) the mitigation and control of ~ ]

accident conditions within the facility. The minimum specified independent and redundant A.C. l

~

and D.C. power sources and distribution systems satisfy the requirements of General Design

= Criteria 17 of Appendix "A" to 10 CFR 50.

For each EDG, the fuel oil transfer system shall be capable of automatically transferring fuel oil to the associated EDG day tank in sufficient quantities to maintain adequate day tank level to suppon full load operation of the EDO.

The ACTION requirements specified for the levels of degradation of the power sources provide restriction upon continued facility operation commensurate with the level of degradation.

The OPERABILITY of the power sources are consistent with the initial condition assumptions of the accident analyses and are based upon maintaining at least one of each of the onsite A.C. and D.C. power sources and associated distribution systems OPERABLE during accident conditions coincident with an assumed loss of offsite power and single failure of the other onsite A.C. source.

Entering the 14 day EDG action statement during power operation has been shown to result in a small increase in the core damage frequency, provided the Alternate A.C. diesel generator (AAC DG) is OPERABLE and the opposite unit's EDGs are both OPERABLE. A Configuration Risk Management Program (CRMP) defined in Administrative Control Section 6.8.4.g is implemented to evaluate risk associated with the EDG outage. The EDG and AAC DG annual unavailability is limited by the Maintenance Rule Program.

When one or more of the diesel generators (i.e., AAC DG or opposite unit's EDGs) required to enter the 14 day actions statement is inoperable or becomes inoperable during the fourteen day action statement of the effected EDO, a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> action statement is entered. If the three diecel generators (i.e., AAC DG or opposite unit's EDGs) required to support entry into the fourteen day action statement are restored to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, the remainder of the 14 day action statement can be used. Re' storing the affected EDG to service removes the conditional OPERABILITY requirements for the AAC DG and opposite unit's EDGs.

. The operability requirements for the AAC DG are specified in the Technical Requirements Manual. In addition, to be considered OPERABLE to support the fourteen day action statement the AAC DG must be capable of providing power to the affected bus (i.e., connectable to the bus with the associated breakers and control power available.) If the AAC DG becomes inoperable NORTH ANNA - UNIT 2 B 3/4 8-1 Amendment No.18, Si,138,-484

1 l

ADMINISTRATIVE CONTROLS 6.8.4.e Radioactive Effluent Controls Program (Cont.)

8) Limitations on the annual and quarterly air doses resulting from noble gases released in gaseous effluents from each unit to areas beyond the SITE BOUNDARY conforming to Appendix I to 10 CFR Part 50,
9) Limitations on the annual and quarterly doses to a MEMBER OF THE PUBLIC from Iodine-131, Iodine-133, tritium, and all radionuclides in particulate form with half-lives greater than 8 days in gaseous effluents released from each unit to areas beyond the SITE BOUNDARY conforming to Appendix 1 to 10 CFR 50,
10) Limitations on the annual dose or dose commitment to any MEMBER OF THE PUBLIC due to releases of radioactivity and to radiation from uranium fuel cycle sources conforming to 40 CFR Part 190.

L Radiological Environmental Monitoring Program A program shall be provided to monitor the radiation and radio nuclides in the environs of the plant. The program shall provide (1) representative measurements of radioactivity in the highest potential exposure pathways, and (2) verification of the accuracy of the effluent monitoring program and modeling of environmental exposure pathways. The program shall (1) be contained in the ODCM,(2) conform to the guidance of Appendix I to 10 CFR Part 50, and (3) include the following:

1) Monitoring, sampling, analysis, and reporting of radiation and radionuclides in the environment in accordance with the methodology and parameters in the ODCM,
2) A Land Use Census to ensure that changes in the use of areas at and beyond the SITE BOUNDARY are identified and that modifications to the monitoring program are made if required by the results of this census, and
3) Participation in a Interlaboratory Comparison Program to ensure that independent checks on the precision and accuracy of the measurements of radioactive materials in environmental sample matrices are performed as part of the quality assurance program for environmental monitoring.
g. Configuration Risk Management Program The Configuration Risk Management Program (CRMP) provides a proceduralized risk-informed assessment to manage the risk associated with equipment inoperability. The program applies to technical specification structures, systems, or components for which a risk-informed allowed outage time has been granted. The program shall include the following elements:
1) Provisions for the control and implementation of a Level 1, at power, internal events, PRA-informed methodology. The assessment shall be capable of evaluating the applicable plant configuration.
2) Provisions for performing an assessment prior to entering the LCO Action Statement for planned activities.

NORTH AlTNA - UNIT 2 6-14c Amendmen* W '! A, i

._--_____--__-________-____--___-_A

ADMINISTRATIVE CONTROLS Configuration Risk Management Program (continued)

3) Provisions for performing an assessment after entering the LCO Action Statement for unplanned entry into the LCO Action Statement.
4) Provisions for assessing the need for additional actions after the discovery of additional equipment out of service conditions while in the LCO Action Statement.
5) Provisions for considering other applicable risk significant contributors such as Level 2 issue and external events, qualitatively or quantitatively.

Current risk-informed action statements include: Action 3.8.1.1.b (d REPORTING REOUIREMENTS ROUTINE REPORTS 6.9.1 In addition to the applicable reporting requirements of Title 10, Code of Federal Regulations, the following reports shall be submitted to the Director of the Regional Office of Inspection and Enforcement unless otherwise noted.

STARTUP REPORTS 6.9.1.1 A summary report of plant startup and power escalation testing shall be submitted following (a) receipt of an operating license, (2) amendment to the license involving a planned increase in power level, (3) installation of fuel that has a different design or has been manufactured by a different fuel supplier, and (4) modifications that may have significantly altered the nuclear, thermal, or hydraulic performance of the plant.

I I

l NORTil ANNA - UNIT 2 614d Amendment No. 47,444, l

40, g, 3

  • O4 0

ATTACHMENT 3 SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA UNITS 1 AND 2 b

.,z -e.

Significant Hazards Consideration On -Septembe'r _1,1995 ' Virginia Electric and Power Company (Virginia Power)

. requested amendments, in the form of changes to the Technical Specifications, to Facility Operating License Numbers NPF-4 and NPF-7 for North Anna Power Station

' Units 1 and 2, respectively. The originally proposed changes would permit a single outage of up to 14 days for each emergency diesel generator (EDG) once every 18

. months in order to perform preventive maintenance. This request was amended on November 18,1997 to request a 14-day Allowed Outage Time (AOT) for any reason.

On January 13,1998, the NRC staff requested additional information to complete the review of the proposed changes and incorporation of a Configuration Risk Management Program in the Administrative Section of Technical Specifications. The currently proposed change will incorporate a Configuration Risk Management Program into the Administrative Section of Technical Specifications, in support of the previous submittals.

In. addition,-Technical Specification 4.8.1.1.2 requires EDG preventive maintenance every 18-months. However, the Fairbanks Morse Owners Group has recommended an increased interval . of up to two years between these preventive maintenance requirements, based upon a substantial data review of experience at operating plants.

The EDG manufacturer, Fairbanks Morse, has recently endorsed this recommendation.

Virginia Power proposes to increase the Technical Specifications maintenance interval from 18 to 24 months. The increased interval will reduce EDG while still supporting the EDG operability requirements.

The Configuration Risk Management Program will ensure that a proceduralized Probabilistic Risk Assessment (PRA) informed process is in place that assesses the overall impact of maintenance on plant risk. The addition of a CRMP is administrative in nature and does not affect the design or operation of any plant system, structure or component. The increased maintenance interval will continue to support EDG operability requirements. Therefore, incorporating a risk management program and the Owner's Group EDG preventive maintenance interval into Technical Specifications does not create a significant hazards consideration as discussed below.

1 Virginia' Electric and Power Company has reviewed the proposed Technical )

Specifications changes against the criteria of 10 CFR 50.92 and has concluded that the )

' changes do not pose a significant hazards consideration. Specifically, operation of North Anna Power Station in accordance with the proposed Technical Specifications changes will not:

a. ' involve a'significant increase in the probability or consequences of an accident

'previously evaluated. ,

The proposed CRMP is administrative in nature in that it only establishes the

. minimum controls necessary to ' evaluate accident risk during plant operations.  ;

The. plant design and operation are.not changed by this administrative type  ;

i Page 1 of 2 l

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change. Further, with -the ' proposed change to the preventive maintenance interval, the EDG reliability remains adequate to perform its function of supporting accident mitigation equipment with emergency electrical power. Therefore, neither the probability of occurrence nor the consequences of an accident'or ma! function of equipment important to safety previously evaluated in the safety analysis report -

are increased.

b. Create the possibility of a new or different kind of accident from'any accident previously evaluated. No new initiators are defined as a result of a review of the PSA model.

Adding the CRMP and changing the EDG preventive maintenance interval in the Technical Specifications does not change any method of operation or create any-new modes of operation.or accident precursors. Therefore, it is concluded that no new or different kind of accident or malfunction from any previously evaluated has been or will be created by the proposed change,

c. The. proposed Technical Specifications changes do ~ not result in a significant reduction .In margin of safety as defined in the basis for any Technical Specifications, incorporating the CRMP and changing the EDG preventive maintenance interval in the Technical Specifications does not affect any accident analysis assumptions or change any Technical Specifications criteria. Therefore, the margin of safety is not changed.

Virginia Electric and Power Company concludes that the activities associated with these proposed Technical Specifications changes satisfy the no significant hazards consideration criteria of 10 CFR 50.92 and, accordingly, a no significant hazards consideration finding is justified.

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