ML102571627

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Issuance of Amendments 260 & 241 Regarding Change to Technical Specification (TS) 3.7.12, Emergency Core Cooling System (ECCS) Pump Room Exhaust Air Cleanup System (Preacs)
ML102571627
Person / Time
Site: North Anna  
Issue date: 11/01/2010
From: V Sreenivas
Plant Licensing Branch II
To: Heacock D
Virginia Electric & Power Co (VEPCO)
Sreenivas V.NRR/DORL/LPL2-1 415-2597
References
TAC ME2413, TAC ME2414
Download: ML102571627 (23)
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NUCLEAR REGULATORY COMMISSION

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WASHINGTON, D.C. 20555-0001 0

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November 1, 2010

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Mr. David A. Heacock President and Chief Nuclear Officer Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711

SUBJECT:

NORTH ANNA POWER STATION, UNITS 1 AND 2, ISSUANCE OF AMENDMENTS TO CHANGE TECHNICAL SPECIFICATION (TS) 3.7.12, EMERGENCY CORE COOLING SYSTEM (ECCS) PUMP ROOM EXHAUST AIR CLEANUP SYSTEM (PREACS) (TAC NOS. ME2413 AND ME2414)

Dear Mr. Heacock:

The U.S. Nuclear Regulatory Commission has issued the enclosed Amendment Nos260and241 to Renewed Facility Operating License Nos. NPF-4 and NPF-7 for the North Anna Power Station, Units 1 and 2. The amendment consists of changes to the Technical Specifications (TSs) in response to your application dated September 28, 2009, as supplemented by letters dated April 8, 2010 and May 10, 2010.

The amendments revise the TSs by adding new Conditions Band C with associated Action Statements and Completion Times to TS 3.7.12 and modifying Conditions A and D. The changes specifically address the filtration function of the ECCS PREACS.

A copy of our related safety evaluation is also enclosed. The Notice of Issuance will be included in the Commission's biweekly Federal Register notice.

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c::%Sreenivas, Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Reguiation Docket Nos. 50-338 and 50-339

Enclosures:

1. Amendment I\\J 0 260 to NPF-4
2. Amendment No.241 to NPF-7
3. Safety Evaluation cc w/encls: Distribution via Listserv

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 VIRGINIA ELECTRIC AND POWER COMPANY DOCKET NO. 50-338 NORTH ANNA POWER STATION, UNIT NO.1 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 260 Renewed License No. NPF-4

1.

The Nuclear Regulatory Commission (the Commission) has found that:

A.

The application for amendment by Virginia Electric and Power Company et aI., (the licensee) dated September 28,2009, as supplemented by letters dated April 8, and May 10, 2010, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations set forth in 10 CFR Chapter I; B.

The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C.

There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations; D.

The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E.

The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.

- 2

2.

Accordingly, the license is amended by changes to paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-4, as indicated in the attachment to this license amendment, and is hereby amended to read as follows:

(2)

Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment NO.260, are hereby incorporated in the renewed license. The licensee shall operate the facility in accordance with the Technical Specifications.

3.

This license amendment is effective as of its date of issuance and shall be implemented within 60 days of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION Gloria Kulesa, Chief Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Attachment:

Changes to License No. NPF-4 and the Technical Specifications Date of Issuance: November 1, 2010

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 VIRGINIA ELECTRIC AND POWER COMPANY DOCKET NO. 50-339 NORTH ANNA POWER STATION, UNIT NO.2 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 241 Renewed License No. NPF-7

1.

The Nuclear Regulatory Commission (the Commission) has found that:

A.

The application for amendment by Virginia Electric and Power Company et aI., (the licensee) dated September 28,2009, as supplemented by letters dated April 8, and May 10, 2010, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations set forth in 10 CFR Chapter I; B.

The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C.

There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations; D.

The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E.

The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.

- 2

2.

Accordingly, the license is amended by changes to paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-7, as indicated in the attachment to this license amendment, and is hereby amended to read as follows:

(2)

Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No.241are hereby incorporated in the renewed license. The licensee shall operate the facility in accordance with the Technical Specifications.

3.

This license amendment is effective as of its date of issuance and shall be implemented within 60 days of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION Gloria Kulesa, Chief Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Attachment:

Changes to License No. NPF-7 and the Technical Specifications Date of Issuance: I~overnber 1, 2010

ATTACHMENT TO LICENSE AMENDMENT NO. 260

. RENEWED FACILITY OPERATING LICENSE NO. NPF-4 DOCKET NO. 50-338 TO LICENSE AMENDMENT NO. 241 RENEWED FACILITY OPERATING LICENSE NO. NPF-7 DOCKET NO. 50-339 Replace the following pages of the Licenses and the Appendix "A" Technical Specifications (TSs) with the enclosed pages as indicated. The revised pages are identified by amendment number and contain vertical lines indicating the areas of change.

Remove Pages Insert Pages Licenses Licenses License No. NPF-4, page 3 License No. NPF-4, page 3 License No. NPF-7, page 3 License No. NPF-7, page 3 3.7.12-1 3.7.12-1 3.7.12-2 3.7.12-3 3.7.12-4 3.7.12-2 3.7.12-5

-3 (2) Pursuant to the Act and 10 CFR Part 70, VEPCa to receive, possess, and use at any time special nuclear material as reactor fuel, in accordance with the limitations for storage and amounts required for reactor operation, as described in the Updated Final Safety Analysis Report; (3) Pursuant to the Act and 10 CFR Parts 30, 40, and 70, VEPCO to receive, possess, and use at any time any byproduct, source, and special nuclear material as sealed neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amounts as required; (4) Pursuant to the Act and 10 CFR Parts 30,40, and 70, VEPCO to receive, possess, and use in amounts as required any byproduct, source, or special nuclear material, without restriction to chemical or physical form, for sample analysis or instrument calibration or associated with radioactive apparatus or component; and (5) Pursuant to the Act and 10 CFR Parts 30 and 70, VEPCO to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility.

C. This renewed operating license shall be deemed to contain and is subject to the conditions specified in the folloWing Commission regulations in 10 CFR Chapter I:

Part 20, Section 30.34 of Part 30. Section 40.41 of Part 40, Sections 50.54 and 50.59 of Part 50, and Section 70.32 of Part 70; is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission now or hereafter in effect; and is subject to the additional conditions specified or incorporated below:

(1) Maximum Power Level VEPCa is authorized to operate the North Anna Power Station. Unit NO.1, at reactor core power levels not in excess of 2940 megawatts (thermal).

(2) Technical Specifications The Technical Sr~ifications contained in Appendix A. as revised through Amendment No 269(re hereby incorporated in the renewed license. The licensee shall operate the facility in accordance with the Technical Specifications.

Renewed License No. NPF-4 NORTH ANNA - UNIT 1 Amendment No. 260

(3) Pursuant to the Act and 10 CFR Parts 30, 40, and 70, VEPCa to receive, possess, and use at any time any byproduct, source, and special nuclear material as sealed neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amounts as required; (4) Pursuant to the Act and 10 CFR Parts 30, 40, and 70, VEPCa to receive, possess, and use in amounts as required any byproduct, source, or special nuclear material, without restriction to chemical or physical form, for sample analysis or instrument calibration or associated with radioactive apparatus or components; and (5) Pursuant to the Act and 10 CFR Parts 30,40, and 70. VEPCa to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility.

C. This renewed license shall be deemed to contain and is SUbject to the conditions specified in the Commission's regUlations as set forth in 10 CFR Chapter ( and is subject to all applicable provisions of the Act and to the rules. regUlations, and orders of the Commission flOW or hereafter in effect; and is subject to the additional conditions specified or incorporated below:

(1) Maximum Power Level VEPca is authorized to operate the facility at steady state reactor core power levels not in excess of 2940 megawatts (thermal).

(2) Technical Specifications The Technical Sper.ifications contained in Appendix A, as revised through Amendment No, 241 (re hereby incorporated in the renewed license. The licensee shall operate the facility in accordance with the Technical Specifications.

(3) Additional Conditions The matters specified in the follOWing conditions shall be completed to the satisfaction of the Commission within the stated time periods follOWing the issuance of the condition or within the operational restrictions indicated. The removal of these conditions shall be made by an amendment to the renewed license supported by a tavorable evaluation by the Commission:

a. If VEPCO plans to remove or to make significant changes in the normal operation of equipment that controls the amount of radioactivity in ef1luents from the North Anna Power Station, the Renewed License No. NPF-7 NORTH ANNA - UNIT 2 ffia1drent rt>.

241

ECCS PREACS 3.7.12 3.7 PLANT SYSTEMS 3.7.12 Emergency Core Cooling System (ECCS) Pump Room Exhaust Air Cleanup System (PREACS)

LCO 3.7.12 Two ECCS PREACS trains shall be OPERABLE.

- - - -- - - - - - - - - NOTE - - - - - - - - - - - -

The ECCS pump room boundary openings not open by design may be opened intermittently under administrative control.

APPLICABILITY:

MODES I, 2, 3, and 4.

ACTIONS

- - - - - - - - - - - - - - - - NOTE - - - - - - - - - - - - - - -

Separate Condition entry is allowed for each Function.

CONDITION REQUIRED ACTION

~OMPLETION TIME A.

One ECCS PREACS train inoperable for reasons other than Condition B.

A.l Restore ECCS PREACS train to OPERABLE status.

7 days North Anna Units 1 and 2 3.7.12-1 Amendments 260 and 241

ECCS PREACS 3.7.12 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B.

One ECCS PREACS train inoperable due to inoperable filtration capability.

B.1.1 Verify ECCS leakage log is less than the maximum allowable unfiltered leakage.

1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> AND B.1.2 Verify by field walkdown that ECCS leakage is less than the maximum allowable unfiltered leakage.

AND Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter B.l.3 Restore ECCS PREACS train to OPERABLE status.

30 days OR B.2 Restore ECCS PREACS train to OPERABLE status.

7 days North Anna Units 1 and 2 3.7.12-2 Amendments 260 and 241

Eces PREACS 3.7.12 ACTIONS CONDITION REQUIRED ACTION

~OMPLETION TIME C.

Two ECCS PREACS trains inoperable due to inoperable filtration capability.

C.1.1 Verify ECCS leakage log is less than the maximum allowable unfiltered leakage.

1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> AND C.1.2 Verify by field walkdown that ECCS leakage is less than the maximum allowable unfiltered leakage.

Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter C.1.3 Restore at least one ECCS PREACS train to OPERABLE status.

14 days OR C.2 Restore at least one ECCS PREACS train to OPERABLE status.

1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> North Anna Units 1 and 2 3.7.12-3 Amendments 260 and 241

ECCS PREACS 3.7.12 ACTIONS CONDITION REQU IRED ACTI ON COMPLETION TIME D.

Two ECCS PREACS trains inoperable due to inoperable ECCS pump room boundary affecting filtration capability.

0.1.1 Verify ECCS leakage log is less than the maximum allowable unfiltered leakage.

AND 0.1.2 Verify by field walkdown that ECCS leakage is less than the maximum allowable unfiltered leakage.

AND 0.1.3 Restore ECCS pump room boundary to OPERABLE status.

OR 0.2 Restore ECCS pump room boundary to OPERABLE status.

1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter 14 days 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Eo Required Action and associated Completion Time not met.

E.1 Be in MODE 3.

AND 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> E.2 Be in MODE 5.

36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.7.12.1 Operate each ECCS PREACS train for

~ 10 continuous hours with the heaters operating.

31 days North Anna Units 1 and 2 3.7.12-4 Amendments 260 and 241

ECCS PREACS 3.7.12 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.7.12.2 Actuate each ECCS PREACS train by aligning Safeguards Area exhaust flow and Auxiliary Building Central exhaust flow through the Auxiliary BUilding HEPA filter and charcoal ad sorber assembly.

31 days SR 3.7.12.3 Perform required ECCS PREACS filter testing in accordance with the Ventilation Filter Testing Program (VFTP).

In accordance wi th the VFTP SR 3.7.12.4 Verify Safeguards Area exhaust flow is diverted and each Auxiliary Building filter bank is actuated on an actual or simulated actuation signal.

18 months SR 3.7.12.5 Verify one ECCS PREACS train can maintain a negative pressure relative to adjacent areas during post accident mode of operation.

18 months on a STAGGERED TEST BASIS North Anna Units 1 and 2 3.7.12-5 Amendments 260 and 241

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 260 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-4 AND AMENDMENT NO. 241 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-7 VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION, UNITS 1 AND 2 DOCKET NOS. 50-338 AND 50-339

1.0 INTRODUCTION

By application dated September 28, 2009 (Agencywide Documents Access and Management System (ADAMS), Accession No. ML092730468), as supplemented by letters dated April 8, 2010 (ADAMS Accession No. ML100990088), May 10,2010 (ADAMS Accession No. ML101300461), and electronic correspondence dated July 6 and 7, 2010 (ADAMS Accession Nos. ML102180069 and ML102180068), Virginia Electric and Power Company (the licensee) submitted a request for changes to the North Anna Power Station, Units 1 and 2 (NAPS 1 and 2), Technical Specifications (TSs). The proposed amendment would revise the TSs requirements for plant systems by adding new Conditions Band C with associated Action Statements and Completion Times to TS 3.7.12 "Emergency Core Cooling System (ECCS) Pump Room Exhaust Air Cleanup System (PREACS),"

and modify Conditions A and D. The licensee stated that the proposed amendment is consistent with the associated design and licensing basis accident analysis assumptions. The supplemental letter provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the staff's original proposed no significant hazard consideration determination.

This safety evaluation (SE) documents the U.S. Nuclear Regulatory Commission (NRC) staff's review of the impact of the proposed TS changes specifically addressing the filtration function of the ECCS PREACS for NAPS 1 and 2.

2.0 REGULATORY EVALUATION

The licensee proposes to change the Action Statements and Completion times for Technical Specification (TS) 3.7.12, "Emergency Core Cooling System (ECCS) Pump Room Exhaust Air Cleanup System (PREACS)." The proposed changes will add new Conditions Band C with ENCLOSURE

- 2 associated Action Statements and Completion Times. Existing Condition Band C will be renumbered as Conditions D and E. The proposed changes will modify Conditions A and D (old Condition B). The changes specifically address the filtration function of ECCS PREACS.

The proposed change will modify "Condition A" to relocate the filtration function from the ventilation requirements of a PREACS train. The "Actions" addressing the cooling (ventilation exhaust mode) function of the ECCS PREACS train will remain unchanged.

"Condition B" will be renumbered as "Condition D." "Condition C" will be renumbered as "Condition E."

The new "Condition B" and "Condition C" will be added. The new "Condition B" will address the operability of the filtration function of one train of ECCS PREACS. The new "Condition C" will address the operability of two trains of ECCS PREACS.

The "Condition D" will be modified to be consistent with the new "Condition B" and "Condition C" to account for ECCS leakage.

The new "Condition E" will be unchanged except it is renumbered from "Condition C" to new "Condition E."

Title 10 of the Code ofFederal Regulations (10 CFR) Part 50.36 establishes the requirements for Technical Specifications for a utilization facility. These Technical Specifications are derived from the analysis and evaluations included in the safety analysis report and its amendments.

Section 50.36(c)(2) provides requirements for the limiting condition for operation (LCD) which is the lowest functional capability or performance level of equipment required for safe operation of the facility.

Section 50.67 provides the limitations of radiological dose for an individual located on the exclusion boundary and outer boundary of the low population zone, and provides for the radiological protection of the personnel occupying the control room under accident conditions.

Appendix A to 10 CFR 50 establishes general design criteria (GDC) for power plants. GDC 19 establishes the requirements for protecting the occupants of the facility control room under normal operating conditions and under accident conditions including loss-of-coolant accidents. GDC 19 establishes maximum radiological dose to control room personnel during an accident.

Additional guides and standards upon which the NRC staff based its review upon are the following:

  • Standard Review Plan (SRP) Section 6.2.1, "Containment Functional Design."

- 3

3.0 TECHNICAL EVALUATION

3.1 Background

The ECCS PREACS consists of both unit-specific subsystems (Unit 1 and Unit 2 Safeguards Exhaust) and a shared subsystem (Auxiliary Building Central Exhaust) and the associated common ductwork. During normal operation, ECCS PREACS provides ventilation for cooling, and the PREACS filters are bypassed.

During emergency operations, the ECCS PREACS dampers realign to direct the ventilation through one of the two Auxiliary Building Central Exhaust charcoal adsorber and high efficiency particulate air (HEPA) filter assemblies.

The existing accident analysis (dose) for North Anna does not credit the ECCS PREACS exhaust filtration until 60 minutes following the onset of the event. This amendment does not change the assumptions or inputs into the existing dose analysis of record.

The accident analysis has been evaluated using ECCS leakage varying from 3,400 cc/hr (cubic centimeters per hour) with no air filtration for the ECCS PREACS to 34,400 cc/hr using ECCS PREACS filtration and various combinations of both. The licensee indicates that no credit is taken for Control Room filtered recirculation flow. The control room, exclusion area boundary, and low population zone doses remained within the regulatory limits.

3.2 Evaluation The staff evaluated the licensee's dose consequence analysis described in the Sections 3.0, "Designl Licensing Bases" and Section 4.0 "Technical Analysis & Safety Considerations," of to the licensee's submittal dated September 28, 2009 (ADAMS Accession No. ML092730468). "Technical Analysis and Safety Considerations" as described in the Section 3.0, included the discussion on monitoring ECCS leakage, system leakage performance, evaluation of potential pump seal leakage, time needed to complete repairs, basis for extended completion time with one train inoperable, basis for extended completion time with two trains operable, and basis for extended completion time with pump room boundary.

Upon reviewing the licensee's assessment of these areas of the review, the NRC staff determined that a request for additional information (RAI) was needed to complete its detailed technical review.

By letter dated April 8, 2010, the licensee provided additional information. Upon review, the NRC staff further determined that the additional clarifications were needed concerning the ECCS pump seal leakage issue that included 1) high head safety injection (HHSI) pump seal model number; (2) cause of the seal leak (for the worst-case historic seal leak) of 1200 cc/hour and its fluid temperature; (3) difference in this leakage at fluid temperature assumed in a design basis accident; (4) mission time for the HHSI pump; and (5) HHSI pump seal vendor (Flowserve) Operating Experience.

- 4 By the electronic correspondence dated July 6 and 7, 2010 (ADAMS Accession Nos.

ML102180069 and ML102180068), the licensee responded to the NRC staffs request for additional information concerning PREACS seal leakage.

The licensee also evaluated the expected maximum allowable unfiltered ECCS leakage and a single failure of the worst case pump seal or valve packing under operating accident conditions; and off site and control room radiological doses with two trains of ECCS PREACS filters inoperable. The licensee concluded that based on the worst case expected increase in ECCS leakage of 1200 cc/hr, due to the single failure of a seal or valve packing, the control room and offsite accident doses will be within the GDC 19 limits.

The NRC staff assessed the licensee's evaluation of the integrity of the seal leakage and determined that the expected seal leakage is within the limits of Regulatory Guide (RG) 1.183 and finds that it meets the GDC 19 limits.

CONDITION A The proposed Technical Specification, TS 3.7.12 Condition A will be applicable when "One ECCS PREACS train inoperable for reasons other Condition B." This change removes the filtration function from the operability requirements of an ECCS PREACS train. Condition B will address the filtration function. The remaining operability requirements for an ECCS PREACS train remain unchanged. The NRC staff considers this change acceptable.

CONDITION B The proposed TS 3.7.12, Condition B, will be applicable when "One ECCS PREACS train inoperable due to inoperable filtration capability." The Required Action B.1.1 specifies verification that "ECCS leakage log is less than the maximum allowable unfiltered leakage" with a Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> AND Required Action B.1.2 directing the plant to "Verify by field walkdown that ECCS leakage is less than the maximum allowable unfiltered leakage" with a Completion Time of "Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter" AND Required Action B.1.3 to "Restore ECCS PREACS train to OPERABLE status" with a Completion Time of 30 days.

The licensee indicates the dose accident analyses show that neither the offsite nor control dose limits will be exceeded when ECCS leakage remains below 3400 cubic centimeters per hour and no PREACS filters are in operation. As per RG 1.183 verification, the ECCS leakage at the start of the accident remains below one-half the value assumed in the accident analysis. This provides reasonable assurance that the accident dose analyses inputs are not exceeded. The remedial action specified in the Required Action B.1.1 and B.1.2 provides defense-in-depth for the remaining PREACS filter assembly. When ECCS leakage exceeds the maximum allowable unfiltered leakage the plant would enter Required Action B.2 or Condition E as applicable.

Therefore, the NRC staff finds the extension of the Completion Time to be acceptable.

CONDITION C The proposed TS 3.7.12, Condition C, will be applicable when "Two ECCS PREACS trains inoperable due to inoperable filtration capability." The Required Action C.2 directing the plant to "Restore one ECCS PREACS train to OPERABLE status" with a Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.

Therefore, the NRC staff finds this change is acceptable.

- 5 The proposed TS 3.7.12, Condition C, will be applicable with Two ECCS PREACS trains inoperable due to inoperable filtration capability." The Required Action C.1.1 specifies verification that "ECCS leakage log is less than the maximum allowable unfiltered leakage" with a Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> AND Required Action C.1.2 directing the plant to "Verify by field walkdown that ECCS leakage is less than the maximum allowable unfiltered leakage" with a Completion Time of "Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter" AND Required Action C.1.3 to "Restore at least one ECCS PREACS train to OPERABLE status" with a Completion Time of 14 days.

The Low Head Safety Injection (LHSI) pumps and the Outside Recirculation Spray (ORS) pumps have tandem pump seals. Clean water is injected between the seals. ECCS leakage will have to overcome the differential between the water pressure inside the pump at the shaft and the pressure of the water injected between the seals. The pump seal water (clean water injected between the tandem seals) will dilute any ECCS leakage through the second seal to the environment.

The HHSI pumps have a single seal. ECCS leakage through the seal discharges directly to the environment. The HHSI pumps are used for normal reactor coolant system (RCS) makeup and during large-break loss-of-coolant accident (LOCA). During a design basis LOCA, at least one train of HHSI operates until RCS pressure decreases sufficiently to allow the LHSI pumps to inject cooling water into the reactor. After the LHSI pumps are in operation providing reactor core cooling the HHSI pumps are not required to operate and may be stopped. The assumptions in RG-1.183 that the ECCS leakage (including through the pump seals) is more than twice the operational limit, accommodates some increase in leakage due to component wear post-accident and provides reasonable assurance that the total ECCS leakage outside the containment assumed in the accident analysis will not be exceeded during the post-accident operating time as required from the HHSI.

The HHSI pumps operate during a small-break LOCA. The required operating mission time for HHSI pumps during a small-break LOCA is longer than for a large-break LOCA. The ECCS is assumed to maintain the core in a coolable geometry and maintain the peak cladding temperature below specified limits. Offsite and onsite accident dose analyses do not assume core damage during a small break LOCA.

RG 1.183 specifies that the ESF systems that recirculate sump water outside of the primary containment are assumed to leak during their intended operation. This release source includes leakage through valve packing glands, pump shaft seals, flanged connections, and other similar components. The radiological consequences from the postulated leakage should be analyzed and combined with consequences postulated for other fission product release paths to determine the total calculated radiological consequences from the LOCA. The leakage should be taken as two times the sum of the simultaneous leakage from all components in the ESF recirculation systems above which the TSs, or licensee commitments to item 111.0.1.1 of NUREG-0737 would require declaring such systems inoperable. The two times multiplier allows for the possibility of increased leakage over the duration of the event.

Generic Safety Issue (GSI) 191, "Assessment of Debris Accumulation on PWR Sump Performance," (ADAMS Accession No. ML080650563) addresses the effect of debris generated in containment during a design basis LOCA. Debris has the potential to affect pump seal performance during the recirculation phase of a design basis LOCA. The major increase in allowed outage time for both trains of PREACS filters being inoperable raised concerns of ECCS

- 6 pump seal failure if a design basis LOCA occurred during this time. The factor of 2 used for the leakage rate in the dose analysis of record helps provide assurance that LOCA generated debris will not increase the ECCS leakage above the 1700 cc/hr limit.

Since 2002, when North Anna converted to Improved Technical Specifications, North Anna entered TS 3.0.3 two times. In each case, the cause was inoperable filtration capability due to a leakage issue associated with dampers and not specifically attributed to charcoal. Entry into Condition C is not expected to be a frequent occurrence.

The staff finds* that the combination of tandem seals on the LHSI and ORS pumps combined with the continuing verification that the ECCS leakage does not exceed the maximum allowable unfiltered limit provides adequate assurance that offsite and on site dose limits will not be exceeded in the event a design basis LOCA occurs during the allowed completion time for TS 3.7.12 Condition C. The licensee's response to GSI-191 (ADAMS Accession no. ML080650563) documents that the "downstream" effects of LOCA generated debris during a LOCA are not likely to cause a catastrophic increase in the leakage from the HHSI pump during a design basis large break LOCA. The "safety factor" of two recommended in the alternate source term guidance (RG-1.183) helps provide assurance that any leakage from the ECCS will not increase beyond that assumed in the accident dose analyses for no PREACS filtration. In addition, entry into a scenario where the filtration capability of both trains of PREACS is inoperable has been historically infrequent. Maintaining the ECCS leakage below that rate where PREACS filtration is required provides assurance that control room and offsite dose limits will be maintained in the event of a design basis LOCA. The NRC staff finds the proposed change acceptable.

CONDITION 0 The proposed TS 3.7.12, Condition 0, will be applicable when "Two ECCS PREACS trains inoperable due to inoperable ECCS pump room boundary affecting filtration capability." The Required Action 0.2 directing the plant to "Restore ECCS pump room boundary to OPERABLE status" with a Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This is similar to the guidance in NUREG-1431 (Standard Technical Specification) TS 3.7.12 Condition B. The NRC staff finds this change acceptable.

The Required Action D.1.1 specifies verification that "ECCS leakage log is less than the maximum allowable unfiltered leakage" with a Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> AND Required Action 0.1.2 directing the plant to "[v]erify by field walkdown that ECCS leakage is less than the maximum allowable unfiltered leakage" with a Completion Time of "Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter" AND Required Action 0.1.3 "Restore ECCS PREACS pump room boundary OPERABLE status" with a Completion Time of 14 days.

The pump room boundary is necessary to assure that any radiological source term from ECCS system leakage is captured by the ventilation system, filtered, and exhausted as analyzed in the offsite and the on-site dose analyses. The NRC staff reviews determined that the inoperable ECCS pump room boundary with ECCS leakage below 1700 cc/hr is enveloped by the current dose analysis of record. As discussed in the review for the changes to Condition C, the NRC staff finds that the combination of tandem seals on the LHSI and ORS pumps combined with the continuing verification that the ECCS leakage does not exceed the maximum allowable unfiltered limit, provides adequate assurance that the offsite and onsite dose limits will not be exceeded during an allowed design basis LOCA. Therefore, the NRC staff finds this change acceptable.

- 7 CONDITION E The licensee's request of renumbering of TS 3.7.12, Condition C to Condition E is administrative.

Therefore, the NRC staff finds the proposed change acceptable.

Monitoring of ECCS Leakage The ECCS leakage is evaluated as: 1) the amount of filtered ECCS leakage from the ECCS pump rooms, and 2) the amount of unfiltered ECCS leakage from sources outside of the ECCS pump rooms. Since the post-accident air leakage from the ECCS pump rooms is exhausted through the ECCS PREACS filters, a larger amount of ECCS leakage can be accommodated from these rooms. The maximum amount of ECCS leakage that can be accommodated from both the pump rooms and remaining areas is established by the licensee's analysis of record (AOR) assumptions, as discussed above. This relationship is documents in Updated Final Safety Analysis Report (UFSAR). If all measured ECCS leakage is conservatively assumed to be located within unfiltered areas, then as long as the total leakage is less than the analyzed value for maximum allowable unfiltered leakage of 1700 cc/hr, as documented in UFSAR, the calculated dose consequence will be maintained within the applicable regulatory limits. The licensee stated that the amount of ECCS leakage is an operating parameter that is periodically monitored by their Operations department and is documented in the Operations ECCS Leakage (Accident Leakage) logs. This LAR proposed the addition of Conditions "B" and "C", and modifications to Condition "0" of TS 3.7.12 that would add additional Required Actions in which the licensee would: 1) Verify ECCS leakage log is less than the maximum allowable unfiltered leakage within 1hr (60 minutes); and 2)

Verify by field walkdown that ECCS leakage is less than the maximum allowable unfiltered leakage once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter.

In response to the RAI requests, the licensee provided documentation dated May 10, 2010, (ADAMS Accession No. ML101300461) to support that in addition to the proposed Required Action statements of TS 3.7.12, ECCS leakage would be conservatively monitored and recorded with adequate defense-in-depth to ensure that the operational limit of 1700 cc/hr (unfiltered) will not be exceeded. The HHSI Charging Pumps are rotated approximately every 30 days to balance the run time and performance of inservice testing. Leakage monitoring of these pump seals and associated valves/piping is performed by operator rounds once per shift (currently 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />) for the running HHSI pump and the normally non-running LHSI and ORS pumps. The non-running HHSI pumps are monitored during operator rounds once daily. Specifically, any leakage is monitored and documented in the ECCS Leakage Log. In addition, the quarterly surveillance testing of the HHSI and LHSI pumps and the 18-month surveillance testing of the ORS pumps also directs North Anna's Operations department to inspect pumps and associated valves for leakage, and to record any leakage in their ECCS Leakage Log. Therefore, with the proposed TS changes, and with additional monitoring policies and/or procedures in place for operator rounds, inservice testing, and/or engineering walkdowns, the NRC staff confirms that the licensee has provided reasonable assurance that the ECCS leakage limits of 1700 cc/hr (unfiltered) and 17,200 cc/hr (filtered) will be maintained. This will remain true even no filtration capacity exists due to both ECCS PREACS trains being inoperable, as described by the proposed changes to TS 3.7.12.

Accident Dose Analysis As described in Section 3.0 of the LAR, the North Anna ECCS PREACS is a two train ventilation system that consists of unit-specific subsystems (Unit 1 and Unit 2 Safeguards Exhaust), a shared

- 8 subsystem (Auxiliary Building Central Exhaust), and the associated common ductwork. The system is operated both during normal operation and during accident conditions; however, during normal operation, the ECCS PREACS only provides cooling for the ECCS pumps. The filters are bypassed. During accident conditions, the ECCS PREACS filters potentially radioactive air that is released from the pump room volume where active ECCS components are located.

In accordance with Chapter 15 of UFSAR, the only accident in which ECCS PREACS is credited is the LOCA. The licensee provided dose consequences information in Section 3.0 of the LAR "Design/Licensing Bases."

The licensee stated that "no changes to the analysis of record were required to support this PREACS License Amendment Request because the current analysis assumes 3400 cc/hr of unfiltered ECCS Leakage." The NAPS current AOR does not take credit for filtered recirculation in the control room. Additionally, in the May 10, 2010, response to the NRC staffs RAI, the licensee states: "Leakage accumulated in the ECCS pump rooms is considered filtered when the PREACS is operable. Areas in the auxiliary building outside the pump rooms are considered unfiltered due to the potential for a release pathway from the auxiliary building to the environment without the benefit of filtration. The current values for allowable ECCS leakage are 17,200 cc/hr filtered or 1700 cc/hr unfiltered". As a result, the licensee concluded that there are no changes to the current AOR pertaining to dose consequences.

The NRC staff reviewed and compared the dose analysis assumptions identified by the licensee as relevant to the proposed change against the assumptions used in the dose AOR for the LOCA event. The NRC staff also determined that the current approved values for allowable ECCS leakage for unfiltered leakage of 1700 cc/hr and filtered leakage of 17,200 cc/hr are not being modified as a result of the proposed changes. The NRC staff concludes that the design basis LOCA dose consequences of 4.1 (control room), 2.1 (exclusion area boundary), and 0.2 (low-population zone) rem total effective dose equivalent (TEDE) remain valid for the proposed changes and are below the required limits of 10 CFR 50.67. Therefore, the NRC staff finds the proposed changes acceptable.

4.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Virginia State official was notified of the proposed issuance of the amendment. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

The amendments change a requirement with respect to the installation or use of facility components within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendments involve no significant increase in the amounts and no significant change in the types of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendments involve no significant hazards considerations, and there has been no public comment on such finding (74 FR 62838).

Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.

- 9 6.0 COI\\JCLUSION The LAR proposes TS changes that will add new conditions Band C with associated Action Statements and Completion Times to Technical Specification 3.7.12, "Emergency Core Cooling System (ECCS) Pump Room Exhaust Air Cleanup System (PREACS)" and modify Conditions A and 0 of the same. The new "Condition E" will be unchanged except it is renumbered from "Condition C" to new "Condition E." The TS Bases B 3.7.12 are modified to incorporate the new Conditions and is included for information.

These changes specifically address the filtration function of the ECCS pump room exhaust air cleanup system (PREACS). These changes are consistent with 10 CFR 50.36, 10 CFR 50.67 and GDC 19 of Appendix A to 10 CFR 50.

Therefore, the NRC Staff has concluded, based on the considerations discussed above, that:

(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributors: Bruce Heida, NRR/DRA Janak Raval, NRR/DSS Laray Benton, NRR/DRA Robert Wolfgang, NRR/CPTB Date: November 1, 2010

November 1, 2010 Mr. David A. Heacock President and Chief Nuclear Officer Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711 SUB~IECT:

NORTH ANNA POWER STATION, UNITS 1 AND 2, ISSUANCE OF AMENDMENTS TO CHANGE TECHNICAL SPECIFICATION (TS) 3.7.12, EMERGENCY CORE COOLING SYSTEM (ECCS) PUMP ROOM EXHAUST AIR CLEANUP SYSTEM (PREACS) (TAC NOS. ME2413 AND ME2414)

Dear Mr. Heacock:

The U.S. Nuclear Regulatory Commission has issued the enclosed Amendment Nos. 260 and 241 to Renewed Facility Operating License Nos. NPF-4 and NPF-7 for the North Anna Power Station, Units 1 and 2. The amendment consists of changes to the Technical Specifications (TSs) in response to your application dated September 28,2009, as supplemented by letters dated April 8,2010 and May 10, 2010.

The amendments revise the TSs by adding new Conditions Band C with associated Action Statements and Completion Times to TS 3.7.12 and modifying Conditions A and D. The changes specifically address the filtration function of the ECCS PREACS.

A copy of our related safety evaluation is also enclosed. The Notice of Issuance will be included in the Commission's biweekly Federal Register notice.

Sincerely, IRA!

Dr. V. Sreenivas, Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-338 and 50-339

Enclosures:

1. Amendment No. 260 to
2. Amendment No. 241 to
3. Safety Evaluation NPF-4 NPF-7 cc w/encls: Distribution via Listserv DISTRIBUTION:

Public LPL2-1 R/F RidsNrrDorlLpl2-1 Resource RidsNrrDirsltsb Resource RidsRgn2MailCenter RidsNrrDorlDprResource RidsAcrsAcnw_MailCTR Resource RidsOgcRpResource RidsNrrPMNorthAnna (hard RidsNrrLAMO'Brien (hard c RDennig, NRR copy) opy)

JRaval, NRR LBenton, NRR BHeida, NRR RWolfgang, NRR TTate, NRR N

ML102571627

InPut OFFICE LPL2-1/PM LPL2-1/LA DSS/SCVB/BC DRNAADB/BC OGC LPL2-1/BC LPL2-1/PM NAME VSreenivas MO'Brien RDennig*

TTate*

DRoth GKulesa VSreenivas DATE 10/5/2010 10/5/2010 09/28/2010 09/10/2010 09/30/2010 10/28/2010 11/112010 OFFICIAL RECORD COpy

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