ML072680945

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Issuance of License Amendments 252 and 232 Control Room Habitability, Using the Technical Specification Task Force Traveler, TSTF-448, Revision 3
ML072680945
Person / Time
Site: North Anna  Dominion icon.png
Issue date: 10/31/2007
From: Richard Jervey
NRC/NRR/ADRO/DORL/LPLII-1
To: Christian D
Virginia Electric & Power Co (VEPCO)
Jervey, Richard 301-415-2728
Shared Package
ML072680874 List:
References
TAC MD5653, TAC MD5654
Download: ML072680945 (22)
v • d • e


Text

October 31, 2007 Mr. David A. Christian 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, UNIT NOS. 1 AND 2, ISSUANCE OF AMENDMENT RE: CONTROL ROOM ENVELOPE HABITABILITY, USING THE TECHNICAL SPECIFICATION TASK FORCE TRAVELER, TSTF-448, REVISION 3 (TAC NOS. MD5653 AND MD5654)

Dear Mr. Christian:

The U.S. Nuclear Regulatory Commission (NRC) has issued the enclosed Amendment Nos. 252 and 232 to Renewed Facility Operating License Nos. NPF-4 and NPF-7 for the North Anna Power Station, Unit Nos. 1 and 2. The amendments change the Technical Specifications (TSs) in response to your application dated May 29, 2007. The amendment modifies the TS requirements related to control room emergency ventilation systems to establish more effective and appropriate actions to ensure the habitability of the control room envelope. The change is based on Technical Specification Task Force (TSTF) traveler, TSTF-448, Revision 3.

A copy of the related Safety Evaluation is enclosed. A Notice of Issuance will be included in the Commission's next regular biweekly Federal Register notice.

Sincerely,

/RA/

Richard A. Jervey, Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-338 and 50-339

Enclosures:

1. Amendment No. 252 to NPF-4
2. Amendment No. 232 to NPF-7
3. Safety Evaluation cc w/encls: See next page

October 31, 2007 Mr. David A. Christian 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, UNIT NOS. 1 AND 2, ISSUANCE OF AMENDMENT RE: CONTROL ROOM ENVELOPE HABITABILITY, USING THE TECHNICAL SPECIFICATION TASK FORCE TRAVELER, TSTF-448, REVISION 3 (TAC NOS. MD5653 AND MD5654)

Dear Mr. Christian:

The U.S. Nuclear Regulatory Commission (NRC) has issued the enclosed Amendment Nos. 252 and 232 to Renewed Facility Operating License Nos. NPF-4 and NPF-7 for the North Anna Power Station, Unit Nos. 1 and 2. The amendments change the Technical Specifications (TSs) in response to your application dated May 29, 2007. The amendment modifies the TS requirements related to control room emergency ventilation systems to establish more effective and appropriate actions to ensure the habitability of the control room envelope. The change is based on Technical Specification Task Force (TSTF) traveler, TSTF-448, Revision 3.

A copy of the related Safety Evaluation is enclosed. A Notice of Issuance will be included in the Commission's next regular biweekly Federal Register notice.

Sincerely,

/RA/

Richard A. Jervey, Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-338 and 50-339

Enclosures:

1. Amendment No. 252 to NPF-4
2. Amendment No. 232 to NPF-7
3. Safety Evaluation cc w/encls: See next page DISTRIBUTION:

Public RidsAcrsAcnwMailCenter LPL2-1 R/F GHill (4 hard copies)

RidsNrrDorlLpl2-1 (EMarinos) RidsNrrDirsItsb (TKobetz)

RidsNrrPMRJervey (hard copy) RidsRgn2MailCenter (Guthrie)

RidsNrrLAMO=Brien (2 hard copies) RidsNrrDorlDpr RidsOgcRp RidsNrrDirsWCartwright Package No.: ML072680874 Amendment No.: ML072680945 Tech Spec No.: ML073060406 *transmitted by memo dated OFFICE NRR/LPL2-1/PM NRR/LPD2-1/LA NRR/DIRS/ITSB OGC NRR/LPL2-1/BC NAME RJervey MO=Brien TKobetz BMizuno EMarinos DATE 10/15/07 10/15/07 9/11/07* 10/23/07 10/31/07 OFFICIAL RECORD COPY

North Anna Power Station, Units 1 & 2 cc:

Mr. David A. Christian Mr. Chris L. Funderburk, Director President and Chief Nuclear Officer Nuclear Licensing & Operations Support Virginia Electric and Power Company Dominion Resources Services, Inc.

Innsbrooks Technical Center Innsbrook Technical Center 5000 Dominion Boulevard 5000 Dominion Blvd.

Glen Allen, VA 23060-6711 Glen Allen, Virginia 23060-6711 Mr. C. Lee Lintecum Office of the Attorney General County Administrator Commonwealth of Virginia Louisa County 900 East Main Street Post Office Box 160 Richmond, Virginia 23219 Louisa, Virginia 23093 Senior Resident Inspector Ms. Lillian M. Cuoco, Esq. North Anna Power Station Senior Counsel U. S. Nuclear Regulatory Commission Dominion Resources Services, Inc. P. O. Box 490 Building 475, 5 th floor Mineral, Virginia 23117 Rope Ferry Road Waterford, Connecticut 06385 Mr. Daniel G. Stoddard Site Vice President Dr. W. T. Lough North Anna Power Station Virginia State Corporation Commission Virginia Electric and Power Company Division of Energy Regulation Post Office Box 402 Post Office Box 1197 Mineral, Virginia 23117-0402 Richmond, Virginia 23218 Dr. Robert B. Stroube, MD, MPH Old Dominion Electric Cooperative State Health Commissioner 4201 Dominion Blvd. Office of the Commissioner Glen Allen, Virginia 23060 Virginia Department of Health Post Office Box 2448 Richmond, Virginia 23218

VIRGINIA ELECTRIC AND POWER COMPANY DOCKET NO. 50-338 NORTH ANNA POWER STATION, UNIT NO. 1 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 252 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 al., (the licensee) dated May 29, 2007, 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. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-4 is hereby amended to read as follows:

(2) Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 252, are hereby incorporated in the renewed license. The licensee shall operate the facility in accordance with the Technical Specifications.

3. Further, Renewed Facility Operating License No. NPF-4 will be amended to add license condition 2.C.(3)f to read as follows:
f. Upon implementation of Amendment No. 252 adopting TSTF-448, Revision 3, the determination of Main Control Room/Emergency Switchgear Room (MCR/ESGR) envelope unfiltered air inleakage as required by TS SR 3.7.10.4 in accordance with TS 5.5.16.c(i), the assessment of MCR/ESGR envelope habitability as required by Specification 5.5.16.c(ii), and the measurement of MCR/ESGR envelope pressure as required by Specification 5.5.16.d, shall be considered met.

Following implementation:

(i) The first performance of SR 3.7.10.4 in accordance with Specification 5.5.16.c(i),

shall be within the specified frequency of 6 years plus the 18-month allowance of SR 3.0.2, as measured from September 21, 2003, the date of the most recent successful tracer gas test, as stated in the March 30, 2004 letter response to Generic Letter 2003-01, or within the next 18 months of the time period since the most recent successful tracer gas test is greater than 6 years.

(ii) The first performance of the periodic assessment of MCR/ESGR envelope habitability, Specification 5.5.16.c(ii), shall be within 3 years, plus the 9-month allowance of SR 3.0.2, as measured from September 21, 2003, the date of the most recent successful tracer gas test, as stated in the March 31, 2004 letter response to Generic Letter 2003-01, or within the next 9 months if the time period since the most recent successful tracer gas test is greater than 3 years.

(iii) The first performance of the periodic measurement of MCR/ESGR envelope pressure, Specification 5.5.16.d, shall be within 18 months, plus the 138 days allowed by SR 3.0.2, as measured from February 27, 2007, the date of the most recent successful pressure measurement test, or within 138 days if not performed previously.

4. This license amendment is effective as of its date of issuance and shall be implemented within 180 days of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION

/RA/

Evangelos C. Marinos, Chief Plant Licensing Branch II-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: October 31, 2007

VIRGINIA ELECTRIC AND POWER COMPANY DOCKET NO. 50-339 NORTH ANNA POWER STATION, UNIT NO. 2 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 232 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 al., (the licensee) dated May 29, 2007, 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. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-7 is hereby amended to read as follows:

(2) Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 232, are hereby incorporated in the renewed license. The licensee shall operate the facility in accordance with the Technical Specifications.

3. Further, Renewed Facility Operating License No. NPF-7 will be amended to add license condition 2.C.(3)f to read as follows:
f. Upon implementation of Amendment No. 232 adopting TSTF-448, Revision 3, the determination of Main Control Room/Emergency Switchgear Room (MCR/ESGR) envelope unfiltered air inleakage as required by TS SR 3.7.10.4 in accordance with TS 5.5.16.c(i), the assessment of MCR/ESGR envelope habitability as required by Specification 5.5.16.c(ii), and the measurement of MCR/ESGR envelope pressure as required by Specification 5.5.16.d, shall be considered met.

Following implementation:

(i) The first performance of SR 3.7.10.4 in accordance with Specification 5.5.16.c(i),

shall be within the specified frequency of 6 years plus the 18-month allowance of SR 3.0.2, as measured from September 21, 2003, the date of the most recent successful tracer gas test, as stated in the March 30, 2004 letter response to Generic Letter 2003-01, or within the next 18 months of the time period since the most recent successful tracer gas test is greater than 6 years.

(ii) The first performance of the periodic assessment of MCR/ESGR envelope habitability, Specification 5.5.16.c(ii), shall be within 3 years, plus the 9-month allowance of SR 3.0.2, as measured from September 21, 2003, the date of the most recent successful tracer gas test, as stated in the March 31, 2004 letter response to Generic Letter 2003-01, or within the next 9 months if the time period since the most recent successful tracer gas test is greater than 3 years.

(iii) The first performance of the periodic measurement of MCR/ESGR envelope pressure, Specification 5.5.16.d, shall be within 18 months, plus the 138 days allowed by SR 3.0.2, as measured from February 27, 2007, the date of the most recent successful pressure measurement test, or within 138 days if not performed previously.

4. This license amendment is effective as of its date of issuance and shall be implemented within 180 days of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION

/RA/

Evangelos C. Marinos, Chief Plant Licensing Branch II-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: October 31, 2007

ATTACHMENT TO LICENSE AMENDMENT NO. 252 RENEWED FACILITY OPERATING LICENSE NO. NPF-4 DOCKET NO. 50-338 AND TO LICENSE AMENDMENT NO. 232 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-4, page 5 License No. NPF-4, page 5 License No. NPF-4, page 6 License No. NPF-4, page 6 License No. NPF-4, page 7 License No. NPF-4, page 7

--- License No. NPF-4, page 8 License No. NPF-7, page 3 License No. NPF-7, page 3 License No. NPF-7, page 5 License No. NPF-7, page 5 License No. NPF-7, page 6 License No. NPF-7, page 6 License No. NPF-7, page 7 License No. NPF-7, page 7

--- License No. NPF-7, page 8 Remove TS Pages Insert TS Pages 3.7.10-1 3.7.10-1 3.7.10-2 3.7.10-2 3.7.13-1 3.7.13-1 3.7.13-2 3.7.13-2 3.7.13-3 3.7.13-3

--- 3.7.13-4 3.7.14-1 3.7.14-1 3.7.14-2 3.7.14-2 5.5-15 5.5-15

--- 5.5-16

--- 5.5-17

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 252 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-4 AND AMENDMENT NO. 232 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-7 VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION, UNIT NOS. 1 AND 2 DOCKET NOS. 50-338 AND 50-339

1.0 INTRODUCTION

By letter dated May 29, 2007, Agencywide Documents Access and Management System (ADAMS)

Accession No. ML071500145, Virginia Electric and Power Company (the licensee) submitted a request for changes to the North Anna Power Station, Unit Nos. 1 and 2 (North Anna 1/2),

Technical Specifications (TSs). The requested changes would modify TS requirements related to control room envelope habitability in accordance with Technical Specification Task Force (TSTF) traveler, TSTF-448, Revision 3.

The staff's proposed no significant hazards consideration determination was published in the Federal Register on July 3, 2007 (72 FR 36523).

On August 8, 2006, the commercial nuclear electrical power generation industry owners group Technical Specifications Task Force (TSTF) submitted a proposed change, TSTF-448, Revision 3, to the improved standard technical specifications (STS) (NUREGs 1430-1434) on behalf of the industry (TSTF-448, Revisions 0, 1, and 2 were prior draft iterations). TSTF-448, Revision 3, is a proposal to establish more effective and appropriate action, surveillance, and administrative STS requirements related to ensuring the habitability of the control room envelope (CRE).

In Nuclear Regulatory Commission (NRC) Generic Letter (GL) 2003-01 (Reference 1), licensees were alerted to findings at facilities that existing TS surveillance requirements for the Control Room Envelope Emergency Ventilation System (CREEVS ) may not be adequate. Specifically, the results of ASTM E741 (Reference 2) tracer gas tests to measure CRE unfiltered inleakage at facilities indicated that the differential pressure surveillance is not a reliable method for demonstrating CRE boundary operability. Licensees were requested to address existing TSs as follows:

Provide confirmation that your technical specifications verify the integrity [i.e., operability]

of the CRE [boundary], and the assumed [unfiltered] inleakage rates of potentially contaminated air. If you currently have a differential pressure surveillance requirement to demonstrate CRE [boundary] integrity, provide the basis for your conclusion that it remains

adequate to demonstrate CRE integrity in light of the ASTM E741 testing results. If you conclude that your differential pressure surveillance requirement is no longer adequate, provide a schedule for:

1) revising the surveillance requirement in your technical specification to reference an acceptable surveillance methodology (e.g., ASTM E741), and
2) making any necessary modifications to your CRE [boundary] so that compliance with your new surveillance requirement can be demonstrated.

If your facility does not currently have a technical specification surveillance requirement for your CRE integrity, explain how and at what frequency you confirm your CRE integrity and why this is adequate to demonstrate CRE integrity.

To promote standardization and to minimize the resources that would be needed to create and process plant-specific amendment applications in response to the concerns described in the GL, the industry and the NRC proposed revisions to CRE habitability system requirements contained in the STS, using the STS change traveler process. This effort culminated in Revision 3 to traveler TSTF-448, AControl Room Habitability,@ which the NRC staff approved on January 17, 2007.

Consistent with the traveler as incorporated into NUREG-1431, the licensee proposed revising action and surveillance requirements in the following Technical Specifications:

- TS 3.7.10, AMain Control Room/Emergency Switchgear Room (MCR/ESGR)

Emergency Ventilation System (EVS) - Modes 1,2,3, and 4.@

- TS 3.7.13, AMain Control Room/Emergency Switchgear Room (MCR/ESGR)

Bottled Air System.@

- TS 3.7.14, AMain Control Room/Emergency Switchgear Room (MCR/ESGR)

Emergency Ventilation System (EVS) - During the Movement of Recently Irradiated Fuel Assemblies.@

- TS 5.5.18, AMain Control Room/Emergency Switchgear Room (MCR/ESGR)

Envelope Habitability Program@, a new administrative controls program.

The purpose of the changes is to ensure that MCR/ESGR envelope (the plant-specific name for CRE) boundary operability is maintained and verified through effective surveillance and programmatic requirements, and that appropriate remedial actions are taken in the event of an inoperable MCR/ESGR envelope boundary.

2.0 REGULATORY EVALUATION

2.1 Control Room and Control Room Envelope NRC Regulatory Guide (RG) 1.196, AControl Room Habitability at Light-water Nuclear Power Reactors,@ Revision 0, May 2003, (Reference 4) uses the term Acontrol room envelope (CRE)@ in addition to the term Acontrol room@ and defines each term as follows:

Control Room: The plant area, defined in the facility licensing basis, in which actions can be taken to operate the plant safely under normal conditions and to maintain the reactor in a safe condition during accident situations. It encompasses the instrumentation and controls necessary for a safe shutdown of the plant and typically includes the critical document reference file, computer room (if used as an integral part of the emergency response plan), shift supervisor's office, operator wash room and kitchen, and other critical areas to which frequent personnel access or continuous occupancy may be necessary in the event of an accident.

Control Room Envelope: The plant area, defined in the facility licensing basis, that in the event of an emergency, can be isolated from the plant areas and the environment external to the CRE. This area is served by an emergency ventilation system, with the intent of maintaining the habitability of the control room. This area encompasses the control room, and may encompass other non-critical areas to which frequent personnel access or continuous occupancy is not necessary in the event of an accident.

NRC RG 1.197, ADemonstrating Control Room Envelope Integrity At Nuclear Power Reactors,@

Revision 0, May 2003 (Reference 5), also contains these definitions, but uses the term CRE to mean both. This is because the protected environment provided for operators varies with the nuclear power facility. At some facilities this environment is limited to the control room; at others, it is the CRE. In this safety evaluation, consistent with the proposed changes to the STS, the CRE will be used to designate both. For consistency, facilities should use the term CRE with an appropriate facility-specific definition derived from the above CRE definition.

2.2 The Bottled Air and Emergency Ventilation Systems (EVS)

The licensee refers to the systems used to maintain control room habitability as Athe emergency habitability system,@ a combination of the bottled air and the EVS. The emergency habitability system provides a protected environment from which operators can control the unit, during airborne challenges from radioactivity, hazardous chemicals, and fire byproducts, such as fire suppression agents and smoke, during both normal and accident conditions.

The emergency habitability system is designed to maintain a habitable environment in the control room envelope for 30 days of continuous occupancy after a Design Basis Accident (DBA) without personnel exceeding 5 rem total effective dose equivalent (TEDE).

The emergency habitability system consists of three redundant trains of EVS (one Unit 1 system and two Unit 2 systems), each capable of maintaining the habitability of the MCR/ESGR envelope and three trains of bottled air including associated piping, valves, and a common exhaust header.

Two of the three EVS and bottled air trains are required for the emergency habitability system to be operable. The emergency habitability system is considered operable when the individual components necessary to limit operator exposure are operable in two trains. A bottled air and EVS train is considered operable when the associated:

$ Fan is operable;

$ High efficiency particulate air (HEPA) filters and charcoal adsorbers are not excessively restricting flow, and are capable of performing their filtration functions;

$ Heater, demister, ductwork, valves, and dampers are operable, and air circulation can be maintained;

$ Bottled air bank, flow path, and common exhaust header are operable; and

$ MCR/ESGR envelope boundary is operable (the single boundary supports both trains).

The MCR/ESGR envelope boundary is considered operable when the measured unfiltered air inleakage is less than or equal to the inleakage value assumed by the licensing basis analyses of DBA consequences to MCR/ESGR occupants.

2.3 Regulations Applicable to Control Room Habitability In Appendix A, AGeneral Design Criteria for Nuclear Power Plants,@ to 10 CFR Part 50, ADomestic Licensing of Production and Utilization Facilities,@ General Design Criteria (GDC) 1, 2, 3, 4, 5, and 19 apply to CRE habitability. A summary of these GDCs follows.

Plant-specific design criteria are described in the facility's Updated Final Safety Analysis Report.

GDC 1, AQuality Standards and Records,@ requires that structures, systems, and components (SSCs) important to safety be designed, fabricated, erected, and tested to quality standards commensurate with the importance of the safety functions performed.

GDC 2, ADesign Basis for Protection Against Natural Phenomena,@ requires that SSCs important to safety be designed to withstand the effects of earthquakes and other natural hazards.

GDC 3, AFire Protection,@ requires SSCs important to safety be designed and located to minimize the effects of fires and explosions.

GDC 4, AEnvironmental and Dynamic Effects Design Bases,@ requires SSCs important to safety to be designed to accommodate the effects of and to be compatible with the environmental conditions associated with normal operation, maintenance, testing, and postulated accidents, including loss-of-coolant accidents (LOCAs).

GDC 5, ASharing of Structures, Systems, and Components,@ requires that SSCs important to safety not be shared among nuclear power units unless it can be shown that such sharing will not significantly impair their ability to perform their safety functions, including, in the event of an accident in one unit, the orderly shutdown and cooldown of the remaining units.

GDC 19, AControl Room,@ requires that a control room be provided from which actions can be taken to operate the nuclear reactor safely under normal conditions and to maintain the reactor in a safe condition under accident conditions, including a LOCA. Adequate radiation protection is to be provided to permit access and occupancy of the control room under accident conditions without personnel receiving radiation exposures in excess of specified values.

Prior to incorporation of TSTF-448, Revision 3, the STS requirements addressing CRE boundary operability resided only in the following CRE ventilation system specifications:

$ NUREG-1430, TS 3.7.10, AControl Room Emergency Ventilation System (CREVS);@

$ NUREG-1431, TS 3.7.10, AControl Room Emergency Filtration System (CREFS);@

$ NUREG-1432, TS 3.7.11, AControl Room Emergency Air Cleanup System (CREACS);@

$ NUREG-1433, TS 3.7.4, A[Main Control Room Environmental Control (MCREC)]

System;@ and

$ NUREG-1434, TS 3.7.3, A[Control Room Fresh Air (CRFA)] System.@

In these specifications, the surveillance requirement associated with demonstrating the operability of the CRE boundary requires verifying that one CREEVS train can maintain a positive pressure relative to the areas adjacent to the CRE during the pressurization mode of operation at a makeup flow rate. Facilities that pressurize the CRE during the emergency mode of operation of the CREEVS have similar surveillance requirements. Other facilities that do not pressurize the CRE have only a system flow rate criterion for the emergency mode of operation. Regardless, the results of ASTM E741 (Reference 2) tracer gas tests to measure CRE unfiltered inleakage at facilities indicated that the differential pressure surveillance (or the alternative surveillance at non-pressurization facilities) is not a reliable method for demonstrating CRE boundary operability.

That is, licensees were able to obtain differential pressure and flow measurements satisfying the SR limits even though unfiltered inleakage was determined to exceed the value assumed in the safety analyses.

In addition to an inadequate surveillance requirement, the action requirements of these specifications were ambiguous regarding CRE boundary operability in the event CRE unfiltered inleakage is found to exceed the analysis assumption. The ambiguity stemmed from the view that the CRE boundary may be considered operable but degraded in this condition, and that it would be deemed inoperable only if calculated radiological exposure limits for CRE occupants exceeded a licensing basis limit; e.g., as stated in GDC-19, even while crediting compensatory measures.

NRC Administrative Letter 98-10, ADispositioning of Technical Specifications That Are Insufficient to Assure Plant Safety,@ (AL 98-10) states that Athe discovery of an improper or inadequate TS value or required action is considered a degraded or nonconforming condition,@ which is defined in NRC Inspection Manual Chapter 9900; see latest guidance in RIS 2005-20 (Reference 3).

AImposing administrative controls in response to an improper or inadequate TS is considered an acceptable short-term corrective action. The NRC staff expects that, following the imposition of administrative controls, an amendment to the TS, with appropriate justification and schedule, will be submitted in a timely fashion.@

Licensees that have found unfiltered inleakage in excess of the limit assumed in the safety analyses and have yet to either reduce the inleakage below the limit or establish a higher bounding limit through re-analysis, have implemented compensatory actions to ensure the safety of CRE occupants, pending final resolution of the condition, consistent with RIS 2005-20.

However, based on GL 2003-01 and AL 98-10, the staff expects each licensee to propose TS changes that include a surveillance to periodically measure CRE unfiltered inleakage in order to

satisfy 10 CFR 50.36(d)(3), which requires a facility's TSs to include surveillance requirements, which it defines as Arequirements relating to test, calibration, or inspection to assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that limiting conditions for operation will be met.@

The NRC staff also expects facilities to propose unambiguous remedial actions, consistent with 10 CFR 50.36(d)(2), for the condition of not meeting the limiting condition for operation (LCO) due to an inoperable CRE boundary. The action requirements should specify a reasonable completion time to restore conformance to the LCO before requiring a facility to be shut down. This completion time should be based on the benefits of implementing mitigating actions to ensure CRE occupant safety and sufficient time to resolve most problems anticipated with the CRE boundary, while minimizing the chance that operators in the CRE will need to use mitigating actions during accident conditions.

2.4 Adoption of TSTF-448, Revision 3, by North Anna Power Station, Units 1 and 2 Adoption of TSTF-448, Revision 3, will assure that the facility's TS LCOs for the emergency habitability system is met by demonstrating unfiltered leakage into the MCR/ESGR is within limits; i.e., the operability of the MCR/ESGR envelope boundary. In support of this surveillance, which specifies the test frequency specified by Regulatory Guide 1.196, TSTF-448 also adds TS administrative controls to assure the habitability of the MCR/ESGR envelope between performances of the ASTM E741 test. In addition, adoption of TSTF-448 will establish clearly stated and reasonable required actions in the event MCR/ESGR envelope boundary unfiltered inleakage is found to exceed the analysis assumption.

The changes made by TSTF-448 to the STS requirements for the emergency habitability system and the MCR/ESGR envelope boundary conform to 10 CFR 50.36(d)(2) and 10 CFR 50.36(d)(3).

Their adoption will better assure that the North Anna 1/2 MCR/ESGR envelope boundary will remain habitable during normal operation and design basis accident conditions. These changes are, therefore, acceptable from a regulatory standpoint.

3.0 TECHNICAL EVALUATION

The NRC staff reviewed the proposed changes against the corresponding changes made to the STS by TSTF-448, Revision 3, which the NRC staff has found to satisfy applicable regulatory requirements, as described above in Section 2.0. The emergency operational mode of the emergency habitability system at North Anna 1/2 pressurizes the MCR/ESGR envelope boundary to minimize unfiltered air inleakage. The proposed changes are consistent with this design.

3.1 Proposed Changes The proposed amendment would strengthen MCR/ESGR boundary habitability TS requirements by changing TS referenced in Section 1.0. Accompanying the proposed TS changes are appropriate conforming technical changes to the TS Bases. The proposed revision to the Bases also includes editorial and administrative changes to reflect applicable changes to the corresponding STS Bases, which were made to improve clarity, conform with the latest information and references, correct factual errors, and achieve more consistency among the STS

NUREGs. Except for editorial changes and plant specific differences, all of these changes are consistent with STS as revised by TSTF-448, Revision 3.

The NRC staff compared the proposed TS changes to the STS, the STS markups and evaluations in TSTF-448. The staff verified that differences from the STS were adequately justified on the basis of plant-specific design or retention of current licensing basis. The NRC staff also reviewed the proposed changes to the TS Bases for consistency with the STS Bases and the plant-specific design and licensing bases, although approval of the Bases is not a condition for accepting the proposed amendment. However, TS 5.5.13, ATS Bases Control Program,@ provides assurance that the licensee has established and will maintain the adequacy of the Bases. The proposed Bases for TS 3.7.10 and TS 3.7.14 refer to specific guidance in NEI [Nuclear Energy Institute]

99-03, AControl Room Habitability Assessment Guidance,@ Revision 0, dated June 2001 (Reference 6), which the NRC staff has formally endorsed, with exceptions, through Regulatory Guide 1.196, AControl Room Habitability at Light-Water Nuclear Power Reactors,@ dated May 2003 (Reference 4).

3.2 Editorial Changes The licensee proposed editorial changes to TS 3.7.10 and TS 3.7.13 to establish standard plant terminology, such as AMCR/ESGR envelope@ in place of ACRE,@ the plant-specific name for the CREEVS (MCR/ESGR EVS), and Aradiological, chemical, and smoke hazards A in place of various phrases to describe the hazards that MCR/ESGR occupants are protected from by the emergency habitability system. These changes improve the usability and quality of the presentation of the TSs, have no impact on safety, and therefore, are acceptable.

3.2.1 TS 3.7.10, AMain Control Room/Emergency Switchgear Room (MCR/ESGR) Emergency Ventilation System (EVS) - Modes 1, 2, 3, 4,@ and TS 3.7.13 AMain Control Room/Emergency Switchgear Room (MCR/ESGR) Bottled Air System.@

The licensee proposed to revise the action requirements of TS 3.7.10, AMCR/ESGR EVS,@ and TS 3.7.13, AMCR/ESGR Bottled Air System,@ to acknowledge that an inoperable MCR/ESGR envelope boundary, depending upon the location of the associated degradation, could cause just one, instead of both trains to be inoperable. The changes made were functionally identical in TS 3.7.10 and TS 3.7.13. This is accomplished by revising Condition A to exclude Condition B, and revising Condition B to address one or more trains, as follows:

$ Condition A One train inoperable for reasons other than Condition B.

$ Condition B One or more trains inoperable due to inoperable MCR/ESGR envelope boundary (applicable in MODE 1, 2, 3, or 4.)

This change clarifies how to apply the action requirements in the event just one train is unable to ensure MCR/ESGR occupant safety within licensing basis limits because of an inoperable MCR/ESGR envelope boundary. It enhances the usability of Conditions A and B with a presentation that is more consistent with the intent of the existing requirements. This change is an administrative change because it neither reduces nor increases the existing action requirements, and therefore is acceptable.

The licensee proposed to replace existing Required Action B.1, ARestore control room boundary to OPERABLE status,@ which has a 24-hour Completion Time, with Required Action B.1, to immediately initiate action to implement mitigating actions; Required Action B.2, to verify, within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, that in the event of a DBA, MCR/ESGR envelope occupant exposures to radiological, chemical, and smoke hazards will not exceed limits; and Required Action B.3, to restore MCR/ESGR envelope boundary to operable status within 90 days.

The 24-hour Completion Time of new Required Action B.2 is reasonable based on the low probability of a DBA occurring during this time period, and the use of mitigating actions as directed by Required Action B.1. The 90-day Completion Time of new Required Action B.3 is reasonable based on the determination that the mitigating actions will ensure protection of MCR/ESGR envelope occupants within analyzed limits while limiting the probability that MCR/ESGR envelope occupants will have to implement protective measures that may adversely affect their ability to control the reactor and maintain it in a safe shutdown condition in the event of a DBA. The 90-day Completion Time is a reasonable time to diagnose, plan and possibly repair, and test most anticipated problems with the MCR/ESGR envelope boundary. Therefore, proposed Actions B.1, B.2, and B.3 are acceptable.

3.2.2 TS 3.7.14 MCR/ESGR EVS The licensee proposed to add a new condition to Action B that states, AOne or more MCR/ESGR EVS trains inoperable due to an inoperable MCR/ESGR envelope boundary during movement of recently irradiated fuel assemblies.@ Accordingly, the new condition is stated with the other condition in Action B using the logical connector AOR@. The practical result of this presentation in format is the same as specifying two separately numbered Actions, one for each condition. Its advantage is to make the TS Actions table easier to use by avoiding having an additional numbered row in the Actions table.

A similar change was made to TS 3.7.13 Action E which added the statement AOne or more required bottled air systems trains inoperable due to an inoperable MRC/ESGR envelope boundary during the movement of recently irradiated fuel assemblies@ using the logical connector AOR.@

These changes will ensure that the Actions table continues to specify a condition for an inoperable MCR/ESGR envelope boundary during Modes 5 and 6 and during refueling. Therefore, this change is administrative and acceptable.

3.2.3 CRE PRESSURIZATION SURVEILLANCE REQUIREMENT In the accident mode of operation, the emergency habitability system isolates unfiltered ventilation air supply intakes, filters the emergency ventilation air supply to the MCR/ESGR envelope, and pressurizes the MCR/ESGR envelope boundary to minimize unfiltered air inleakage past the MCR/ESGR envelope boundary. The licensee proposed to delete the MCR/ESGR EVS envelope boundary pressurization surveillance requirements (SR 3.7.10.4 and SR 3.7.14.3). These SRs require verifying that each MCR/ESGR EVS air system train can maintain a pressure of 0.04 inches water gauge, relative to the adjacent areas during the pressurization mode of operation with a make-up flow between 900 cfm and 1100 cfm. The deletion of this SR is proposed because measurements of unfiltered air leakage into the CRE at numerous reactor facilities demonstrated

that a basic assumption of this SR, an essentially leak-tight CRE boundary, was incorrect for most facilities. Hence, meeting this SR by achieving the required CRE pressure is not necessarily a conclusive indication of CRE boundary leak tightness, i.e., CRE boundary operability. In its response to GL 2003-01, dated March 30, 2004, the licensee reported that it had determined that the North Anna 1/2 MCR/ESGR surveillances were adequate to demonstrate the operability of the MCR/ESGR envelope boundary. However, the licensee proposes to replace the pressurization surveillances with inleakage measurement SRs and an MCR/ESGR Envelope Habitability Program in TS Section 5.5, consistent with the approved version of TSTF-448 in their amendment request dated May 29, 2007. Based on the adoption of TSTF-448, Revision 3, the licensee's proposal to revise SR 3.7.10.4 and SR 3.7.14.3 to reference the MCR/ESGR envelope habitability program is acceptable.

The proposed MCR/ESGR envelope boundary inleakage measurements SR 3.7.10.4 and SR 3.7.14.3 state, APerform required MCR/ESGR envelope unfiltered air inleakage testing in accordance with the MCR/ESGR Envelope Habitability Program.@ The MCR/ESGR Envelope Habitability Program TS, proposed TS 5.5.16, requires that the program include ARequirements for determining the unfiltered air inleakage past the MCR/ESGR envelope boundary into the MCR/ESGR in accordance with the testing methods and at the frequencies specified in Sections C.1 and C.2 of RG 1.197, Revision 0 (Reference 5). This guidance references ASTM E741 (Reference 2) as an acceptable method for ascertaining the unfiltered leakage into the MCR/ESGR envelope. The licensee has proposed to follow this method. Therefore, the proposed MCR/ESGR envelope inleakage measurement SR is acceptable.

3.4 TS 5.5.16, MCR/ESGR Envelope Boundary Habitability Program The proposed administrative controls program TS is consistent with the model program TS in TSTF-448, Revision 3. In combination with SR 3.7.10.4 and SR 3.7.14.3, this program is intended to ensure the operability of the MCR/ESGR envelope boundary, which as part of an operable emergency habitability system will ensure that MCR/ESGR envelope habitability is maintained such that MCR/ESGR envelope occupants can control the reactor safely under normal conditions and maintain it in a safe condition following a radiological event, hazardous chemical release, or a smoke challenge. The program shall ensure that adequate radiation protection is provided to permit access and occupancy of the MCR/ESGR envelope under DBA conditions without personnel receiving radiation exposures in excess of 5 rem total effective dose equivalent (TEDE) for the duration of the accident.

A MCR/ESGR Envelope Boundary Habitability Program TS acceptable to the NRC staff requires the program to contain the following elements:

  • Definitions of MCR/ESGR envelope and MCR/ESGR envelope boundary. This element is intended to ensure that these definitions accurately describe the plant areas that are within the MCR/ESGR envelope boundary, and also the interfaces that form the MCR/ESGR envelope boundary, and are consistent with the general definitions discussed in Section 2.1 of this safety evaluation. Establishing what is meant by the MCR/ESGR envelope and the MCR/ESGR envelope boundary will preclude ambiguity in the implementation of the program.
  • Configuration control and preventive maintenance of the MCR/ESGR envelope boundary.

This element is intended to ensure the MCR/ESGR envelope boundary is maintained in its design condition. Guidance for implementing this element is contained in RG 1.196 (Reference 4), which endorsed, with exceptions, NEI 99-03 (Reference 6). Maintaining the MCR/ESGR envelope boundary in its design condition provides assurance that its leak-tightness will not significantly degrade between MCR/ESGR envelope inleakage determinations.

  • Assessment of MCR/ESGR envelope habitability at the frequencies stated in Sections C.1 and C.2 of RG 1.197, Revision 0 (Reference 5), and measurement of unfiltered air leakage into the MCR/ESGR envelope in accordance with the testing methods and at the frequencies stated in Sections C.1 and C.2 of RG 1.197. The licensee proposed the following exception to C.2 of RG 1.197, to be listed in the TS with this program element.

Exceptions were taken to RGs 1.52, 1.78, and 1.83, and are documented in the UFSAR/current licensing basis. This element is intended to ensure that the plant assesses MCR/ESGR envelope habitability consistent with Sections C.1 and C.2 of Regulatory Guide 1.197 and NRC approved exceptions. Assessing MCR/ESGR envelope habitability at the NRC accepted frequencies provides assurance that significant degradation of the MCR/ESGR envelope boundary will not go undetected between MCR/ESGR envelope inleakage determinations. Determination of MCR/ESGR envelope inleakage using test methods acceptable to the NRC staff assures that test results are reliable for ascertaining MCR/ESGR envelope boundary operability. Determination of MCR/ESGR envelope inleakage at the NRC-accepted frequencies provides assurance that significant degradation of the MCR/ESGR envelope boundary will not occur between MCR/ESGR envelope inleakage determinations.

  • Measurement of MCR/ESGR envelope pressure with respect to all areas adjacent to the MCR/ESGR envelope boundary at designated locations for use in assessing the MCR/ESGR envelope boundary at a frequency of 18 months on a staggered test basis (with respect to the MCR/ESGR EVS trains). This element is intended to ensure that MCR/ESGR envelope differential pressure is regularly measured to identify changes in pressure warranting evaluation of the condition of the MCR/ESGR envelope boundary.

Obtaining and trending pressure data provides additional assurance that significant degradation of the MCR/ESGR envelope boundary will not go undetected between MCR/ESGR envelope inleakage determinations.

  • Quantitative limits on unfiltered inleakage. This element is intended to establish the MCR/ESGR envelope inleakage limit as the MCR/ESGR envelope unfiltered infiltration rate assumed in the MCR/ESGR envelope occupant radiological consequence analyses of DBAs. Having an unambiguous criterion for the MCR/ESGR envelope boundary to be considered operable in order to meet LCOs 3.7.10, 3.7.13, and 3.7.14 will ensure that associated action requirements will be consistently applied in the event of MCR/ESGR envelope degradation resulting in inleakage exceeding the limit.

Consistent with TSTF-448, Revision 3, the program states that the provisions of SR 3.0.2 are applicable to the program frequencies for performing the activities required by program paragraph number c, parts (i) and (ii) (assessment of MCR/ESGR envelope habitability and measurement of MCR/ESGR envelope inleakage), and paragraph number 5.5.16.d (measurement of MCR/ESGR

envelope differential pressure). This statement is needed to avoid confusion. SR 3.0.2 is applicable to the surveillance that references the testing in the MCR/ESGR envelope Habitability Program. However, SR 3.0.2 is not applicable to Administrative Controls unless specifically invoked. Providing this statement in the program eliminates any confusion regarding whether SR 3.0.2 is applicable, and is acceptable.

Consistent with TSTF-448, Revision 3, proposed TS 5.5.16 states that (1) a MCR/ESGR envelope Habitability Program shall be established and implemented, (2) the program shall include all of the NRC-staff required elements, as described above, and (3) the provisions of SR 3.0.2 shall apply to program frequencies. Therefore, TS 5.5.16, which is consistent with the model program TS approved by the NRC staff in TSTF-448, Revision 3, is acceptable.

3.5 Implementation of New Surveillance and Assessment Requirements by the Licensee The licensee has proposed license conditions regarding the initial performance of the new surveillance and assessment requirements. The new license conditions adopted the conditions in Section 2.3 of the model application published in the Federal Register on January 17, 2007 (72 FR 2022). Plant-specific changes were made to the proposed license conditions. The proposed plant-specific license conditions are consistent with the model application, and are 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 a facility component located within the restricted area as defined in 10 CFR Part 20 and change surveillance requirements. 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 consideration, and there has been no public comment on the finding published July 3, 2007, (72 FR 36523). The amendment also relates to changes in recordkeeping, reporting, or administrative procedure or requirement. Accordingly, the amendments meet the eligibility criteria for categorical exclusions set forth in 10 CFR 51.22(c)(9) and (c)(10). 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.

6.0 CONCLUSION

The Commission has concluded, on the basis of 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 amendments will not be inimical to the common defense and security or to the health and safety of the public.

7.0 REFERENCES

1. NRC Generic Letter 2003-01, Control Room Habitability, dated June 12, 2003, (GL 2003-01).
2. ASTM E 741 - 00, Standard Test Method for Determining Air Change in a Single Zone by Means of a Tracer Gas Dilution, 2000 (ASTM E741).
3. NRC Regulatory Issue Summary 2005-20: Revision to Guidance Formerly restricted in NRC Generic Letter 91-18, Information to Licensees Regarding Two NRC Inspection Manual Sections on Resolution of Degraded and Nonconforming Conditions and on Operability, dated September 26, 2005 (RIS 2005-20).
4. Regulatory Guide 1.196, Control Room Habitability at Light-Water Nuclear Power Reactors, Revision 0, dated May 2003.
5. Regulatory Guide 1.197, Demonstrating Control Room Envelope Integrity at Nuclear Power Reactors, Revision 0, dated May 2003.
6. NEI 99-03, Control Room Habitability Assessment Guidance, Revision 0, dated June 2001.
7. Virginia Electric and Power Company (Dominion), North Anna Power Station, Units 1 and 2, Proposed Amendment Request Control Room Envelope Habitability in accordance with TSTF-448, Revision 3 using the Consolidated Line Item Improvement Process, dated May 29, 2007, ADAMS ML071500145
8. Virginia Electric and Power Company (Dominion), North Anna Power Station, Units 1 and 2, Generic Letter 2003-01, Control Room Habitability Control Room Testing and Technical Information Submittal, dated March 30, 2004, ADAMS ML040970428.

Principal Contributor: William Cartwright Date: October 31, 2007

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