ML13275A094: Difference between revisions

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:  The proposed license amendment (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13260A256) requests the changes to the Technical Specification (TS) 3.8.1, "AC Sources-Operating."  TS  
:  The proposed license amendment (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13260A256) requests the changes to the Technical Specification (TS) 3.8.1, "AC Sources-Operating."  TS  


3.8.1 contains Surveillance Requirement (SR) 3.8.1.8, which requires verification of the  
====3.8.1 contains====
Surveillance Requirement (SR) 3.8.1.8, which requires verification of the  


capability to manually transfer Unit 1 4.16 kV ESF bus AC power sources from the normal  
capability to manually transfer Unit 1 4.16 kV ESF bus AC power sources from the normal  

Revision as of 23:00, 12 October 2018

Request for Publication in Biweekly Fr Notice - Notice of Consideration of Issuance of Amendments to Facility Operating Licenses, Proposed No Significant Hazards Consideration Determination, and Opportunity for a Hearing (TAC No. MF2721)
ML13275A094
Person / Time
Site: North Anna Dominion icon.png
Issue date: 10/04/2013
From: V Sreenivas
Plant Licensing Branch II
To:
Division of Operating Reactor Licensing
Sreenivas V, NRR/DORL 415-2597
References
TAC MF2721
Download: ML13275A094 (4)


Text

October 4, 2013

MEMORANDUM TO: Biweekly Notice Coordinator

FROM: V. Sreenivas, Project Manager

/RA/ Plant Licensing Branch II-1

Division of Operating Reactor Licensing

Office of Nuclear Reactor Regulation

SUBJECT:

REQUEST FOR PUBLICATION IN BIWEEKLY FR NOTICE - NOTICE OF CONSIDERATION OF ISSUANCE OF AMENDMENTS TO FACILITY

OPERATING LICENSES, PROPOSED NO SIGNIFICANT HAZARDS

CONSIDERATION DETERMINATION, AND OPPORTUNITY FOR A

HEARING (TAC NO. MF2721)

Virginia Electric and Power Company, Docket No. 50-339, North Anna Power Station, Unit No.

2, Louisa County, Virginia Date of amendment request

September 10, 2013 Description of amendment request
The proposed license amendment (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13260A256) requests the changes to the Technical Specification (TS) 3.8.1, "AC Sources-Operating." TS

3.8.1 contains

Surveillance Requirement (SR) 3.8.1.8, which requires verification of the

capability to manually transfer Unit 1 4.16 kV ESF bus AC power sources from the normal

offsite circuit to the alternate required offsite circuit and this surveillance is only applicable to

Unit 1. Dominion is developing a plant modification to install an alternate offsite power feed to

each of the two 4.16 kV ESF buses for Unit 2, such that it will be similar to the Unit 1 design.

Therefore, the proposed change would delete Note 1 to SR 3.8.1.8 to remove the limitation that

excludes Unit 2 and will be consistent with the verification currently performed for Unit 1.

Basis for proposed no significant hazards consideration determination

As required by 10 CFR 50.91(a), the licensee has provided its analysis of the issue of no significant hazards

consideration, which is presented below:

Biweekly Notice Coordinator

1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No

The previously evaluated accident that could be affected is a complete loss of offsite power (LOOP). Analyses have been performed to confirm that power

distribution system voltages and currents with both of the new Unit 2 alternate

normal to emergency bus ties in service are adequate during a unit trip scenario.

The conditions under which the Unit 2 manual transfer capability is verified are

the same as Unit 1. The verification test may only be performed under conditions

that will not challenge steady state operation or challenge the safety of the unit.

Therefore, the Unit 2 verification test (manual transfer between Unit 2 normal

offsite circuit and alternate required offsite circuit) will not significantly increase

the probability of a LOOP.

Should a LOOP occur, the consequences are unaffected by availability of offsite

power (normal offsite circuit and alternate required offsite circuit). Therefore, the

Unit 2 verification test (normal offsite circuit and alternate required offsite circuit)

will not affect the consequences of an accident previously evaluated.

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

Response: No The purpose of the surveillance test is to verify the capability to manually transfer AC power sources from the normal offsite circuit to the alternate required offsite

circuit.

The only effect of the change is to permit the new Unit 2 required offsite circuits

to be tested in the same manner and frequency as the corresponding Unit 1

circuits. Since the Unit 2 circuits are similar to the Unit 1 circuits, and the Unit 1

test is a required TS Surveillance to demonstrate operability of the alternate

offsite circuits, permitting the Unit 2 circuits to undergo the same surveillance test

will not create the possibility of a new or different kind of accident from any

accident previously evaluated.

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No

Biweekly Notice Coordinator

The proposed change enables SR testing of the new Unit 2 alternate offsite AC

circuits to verify the capability to manually transfer AC power sources from the

normal offsite circuit to the alternate required offsite circuit as is performed in

Unit 1.

The margin of safety is related to the confidence in the ability of the fission

product barriers to perform their design functions during and following an

accident situation and the ability of the ECCS to provide adequate core cooling.

These barriers include the fuel cladding, the reactor coolant system, and the

containment system. The proposed change does not directly affect these

barriers, nor does it involve any adverse impact on the Class 1E circuits or SSCs supplied by Class 1E power. In fact, it enhances the ability to power the required

ECCS equipment during accident conditions. Therefore, the proposed change

will not involve a significant reduction in a margin of safety.

The NRC staff has reviewed the licensee's analysis and, based on this review, it appears that the three standards of 50.92(c) are satisfied. Therefore, the NRC staff proposes to

determine that the amendment request involves no significant hazards consideration.

Attorney for licensee

Lillian M. Cuoco, Senior Counsel, Dominion Resources Services, Inc., 120 Tredegar Street, RS-2, Richmond, VA 23219

NRC Branch Chief

Robert Pascarelli.

Biweekly Notice Coordinator The proposed change enables SR testing of the new Unit 2 alternate offsite AC circuits to verify the capability to manually transfer AC power sources from the

normal offsite circuit to the alternate required offsite circuit as is performed in

Unit 1.

The margin of safety is related to the confidence in the ability of the fission

product barriers to perform their design functions during and following an

accident situation and the ability of the ECCS to provide adequate core cooling.

These barriers include the fuel cladding, the reactor coolant system, and the

containment system. The proposed change does not directly affect these

barriers, nor does it involve any adverse impact on the Class 1E circuits or SSCs supplied by Class 1E power. In fact, it enhances the ability to power the required

ECCS equipment during accident conditions. Therefore, the proposed change

will not involve a significant reduction in a margin of safety.

The NRC staff has reviewed the licensee's analysis and, based on this review, it appears that the three standards of 50.92(c) are satisfied. Therefore, the NRC staff proposes to

determine that the amendment request involves no significant hazards consideration.

Attorney for licensee

Lillian M. Cuoco, Senior Counsel, Dominion Resources Services, Inc., 120 Tredegar Street, RS-2, Richmond, VA 23219

NRC Branch Chief

Robert Pascarelli.

DISTRIBUTION

Nonpublic LPL2-1 R/F

RidsNrrDorlLpl2-1 RidsNrrPMNorthanna (hard copy)

RidsNrrLASFigueroa Resource

ADAMS Accession Number: ML13275A094 OFFICE NRR/LPL2-1/PM NRR/LPL2-1/LA NRRLPL2-1/BC NRR/LPL2-1/PM

NAME VSreenivas SFigueroa RPascarelli VSreenivas

DATE 10/2/13 10/2/13 10/3/13 10/4/13 OFFICIAL RECORD COPY