ML13196A079

Request for Additional Information Regarding Overall Integrated Plan for Reliable Spent Fuel Pool Instrumentation

ML13196A079
Person / Time
Site:	Saint Lucie
Issue date:	07/16/2013
From:	Siva Lingam Plant Licensing Branch II
To:	Nazar M Florida Power & Light Co
Lingam S
References
TAC MF0090, TAC MF0091
Download: ML13196A079 (10)

Text

UNrrED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555*0001 July 16, 2013 Mr. Mano Nazar Executive Vice President and Chief Nuclear Officer Florida Power and Light Company P.O. Box 14000 Juno Beach, Florida 33408-0420

SUBJECT:

ST. LUCIE NUCLEAR POWER PLANT, UNITS 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING OVERALL INTEGRATED PLAN FOR RELIABLE SPENT FUEL POOL INSTRUMENTATION (TAC NOS. MF0090 AND MF0091)

Dear Mr. Nazar:

By letter dated February 28, 2013, Florida Power & Light Company submitted an Overall Integrated Plan in response to the March 12,2012, Commission Order modifying licenses with regard to requirements for Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051) for St. Lucie Nuclear Power Plant, Units 1 and 2. The NRC staff is reviewing your submittal and has determined that additional information is required to complete the reviews. The specific information requested is addressed in the enclosure to this letter. This request was communicated to Mr. Ken Frehafer of your staff, and based on Mr. Frehafer's e-mail dated July 9,2013, a response would be provided by August 1, 2013. If any part of this information is not available by such date, please provide the date this information will be submitted.

Should you have any questions, please feel free to contact me at 301-415-1564.

Sincerely,

~~.~

Siva P. Lingam, Project Manager Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-335 and 50-389

Enclosure:

Request for Additional Information cc w/enclosure: Distribution via Listserv

REQUEST FOR ADDITIONAL INFORMATION OVERALL INTEGRATED PLAN IN RESPONSE TO ORDER EA-12-051, "RELIABLE SPENT FUEL POOL INSTRUMENTATION" FLORIDA POWER & LIGHT COMPANY ST. LUCIE NUCLEAR POWER PLANT. UNITS 1 AND 2 DOCKETNUMBERS5~335AND50~89

1.0 INTRODUCTION

By letter dated February 28, 2013 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13063A026), Florida Power & Light Company submitted an Overall Integrated Plan (OIP) in response to the March 12,2012, U.S. Nuclear Regulatory Commission (NRC) Order modifying licenses with regard to requirements for Reliable Spent Fuel Pool [SFP]

Instrumentation (Order Number EA-12-051; ADAMS Accession No. ML12054A679) for St. Lucie Nuclear Power Plant, Units 1 and 2. The NRC staff endorsed Nuclear Energy Institute (NEI) 12 02 "Industry Guidance for Compliance with NRC Order EA-12-051, to Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation," Revision 1, dated August 2012 (ADAMS Accession No. ML12240A307), with exceptions, as documented in Interim Staff Guidance 2012-03 "Compliance with Order EA-12-051, Reliable Spent Fuel Pool Instrumentation,"

Revision 0, dated August 29,2012 (ADAMS Accession No. ML12221A339).

The NRC staff has reviewed the February 28, 2013, response by the licensee and determined that the following Request for Additional Information (RAI) is needed to complete its Technical Review.

2.0 LEVELS OF REQUIRED MONITORING The OIP states, in part, that:

Key spent fuel pool water levels:

1. Level adequate to support operation of the normal fuel pool cooling system Elevation 56'-0" for both Units 1 and 2. This elevation is derived from Unit 1 UFSAR [Updated Final Safety Analysis Report] Section 9.1 and is shown on isometric drawings 8770-G-125 Sheet FS-W-3 and 2998-G-125 Sheet FS-W-6 (References 10, 11 & 12 respectively).

2. Level adequate to provide substantial radiation shielding for a person standing on the spent fuel pool operating deck - An elevation approximately 10' above the highest fuel rack is utilized, with specific elevations as follows:

- 2 Unit 1: EI. 46"-3" based on Unit 1 FSAR Fig. 1.2-19 (Reference 17) in conjunction with plant drawings 8770-11884, 8770-11885 &8770-11890 (References 13 thru 15 respectively).

Unit 2: EI. 46"-5" based on Unit 2 FSAR Fig. 1.2-17 (Reference 18) and plant drawing 2998-18511 (Reference 16).

These elevations are approximately 10' above the top of the fuel racks (see level 3 elevations below)...

3. Level where fuel remains covered Unit 1: EI. 36"-3", based on Unit 1 FSAR Fig. 1.2-19 (Reference 17) in conjunction with plant drawings 8770-11884, 8770-11885 & 8770-11890 (References 13 thru 15 respectively).

Unit 2: EI. 36"-5", based on Unit 2 FSAR Fig. 1.2-17 (Reference 18) and plant drawing 2998-18511 (Reference 16).

RAI-1

Please provide the following:

a) For Level 1, specify how the identified location represents the HIGHER of the two pOints described in the NEI 12-02 guidance for this level.

b) A clearly labeled sketch depicting the elevation view of the proposed typical mounting arrangement for the portions of instrument channel consisting of permanent measurement channel equipment (e.g., fixed level sensors and/or stilling wells, and mounting brackets). Indicate on this sketch the datum values representing Level 1, Level 2, and Level 3, as well as the top of the fuel racks. Indicate on this sketch the portion of the level sensor measurement range that is sensitive to measurement of the fuel pool level, with respect to the Level 1,

Level 2, and Level 3 datum points.

3.0 INSTRUMENTATION DESIGN FEATURES 3.1 Arrangement The OIP states, in part. that:

The two SFP level instrument channels will be installed in diverse locations, arranged in a manner that provides reasonable protection of the level indication function against missiles that may result from damage to the structure over the SFP. As indicated above. the primary and backup SFP level sensors will be installed in the South side of each unit's SFP, as close to the oppOSite corners as practical to maintain maximum attainable separation. Sensor conditioning electronics and battery backup will be mounted in a remote location separated

- 3 from the SFP by a reinforced concrete wall(s) which will provide suitable radiation shielding for the electronics.

RAI-2

Please provide a clearly labeled sketch or marked-up plant drawing of the plan view of the SFP area, depicting the SFP inside dimensions, the planned locations/placement of the primary and back-up SFP level sensors, and the proposed routing of the cables that will extend from the sensors toward the location of the local electronics cabinets and read-out/display devices in the main control room or alternate accessible location.

3.2 Mounting The OIP states, in part, that:

Mounting will be Seismic Class I. Installed equipment will be seismically qualified to withstand the maximum seismic ground motion considered in the design of the plant area in which it is installed.

RAI-3

Please provide the following:

a) The design criteria that will be used to estimate the total loading on the mounting device(s), including static weight loads and dynamic loads. Describe the methodology that will be used to estimate the total loading, inclusive of design basis maximum seismic loads and the hydrodynamic loads that could result from pool sloshing or other effects that could accompany such seismic forces.

b) A description of the manner in which the level sensor (and stilling well, if appropriate) will be attached to the refueling floor and/or other support structures for each planned point of attachment of the probe assembly. Indicate in a schematic the portions of the level sensor that will serve as points of attachment for mechanical/mounting or electrical connections.

c) A description of the manner by which the mechanical connections will attach the level instrument to permanent SFP structures so as to support the level sensor assembly.

3.3 Qualification The OIP states, in part, that:

Components of the instrument channels will be qualified for shock and vibration using one or more of the following methods:

• Components are supplied by manufactures using commercial quality programs (such as IS09001, Quality management systems - Requirements (Reference 8>> with shock and

- 4 vibration requirements included in the purchase specification at levels commensurate with portable hand-held device or transportation applications; Components have a substantial history of operational reliability in environments with significant shock and vibration loadings, such as transportation applications; or components are inherently resistant to shock and vibration loadings, such as cables.

The effects of postulated seismic events on installed instrument channel components (with the exception of battery chargers and replaceable batteries),

will be verified to ensure that the equipment design and installation is robust. Applicable components of the instrument channels will be qualified by the manufacturer (or otherwise tested) for seismic effects at response levels commensurate with the equipment mounting location. Instrument channel qualification will be based on the guidance provided in Sections 7, 8, 9, and 10 of IEEE [Institute of Electrical and Electronics Engineers] Standard 344-2004, IEEE Recommended Practice for Seismic Qualification of Class 1 E Equipment for Nuclear Power Generating Stations, (Reference 9) or a substantially similar industrial standard...

RAI-4

Please provide the following:

a) A description of the specific method or combination of methods you intend to apply to demonstrate the reliability of the permanently installed equipment under Beyond*

Design-Basis (BOB) ambient temperature, humidity, shock, vibration, and radiation conditions.

b) A description of the testing and/or analyses that will be conducted to provide assurance that the equipment will perform reliably under the worst-case credible design basis loading at the location where the equipment will be mounted. Include a discussion of this seismic reliability demonstration as it applies to a) the level sensor mounted in the SFP area, and b) any control boxes, electronics, or read-out and re-transmitting devices that will be employed to convey the level information from the level sensor to the plant operators or emergency responders.

c) A description of the specific method or combination of methods that will be used to confirm the reliability of the permanently installed equipment such that following a seismic event the instrument will maintain its required accuracy.

3A Independence The OIP states, in part, that:

The primary instrument channel will be redundant to and independent of the backup instrument channel. Independence will be obtained through separation of the sensors, indication, backup battery power supplies, associated cabling and channel power feeds.

- 5 RAI-S Please provide the following:

a) A description of how the two channels of the proposed level measurement system in each pool meet this requirement so that the potential for a common cause event to adversely affect both channels is minimized to the extent practicable.

b) Further information describing the design and installation of each level measurement system, consisting of level sensor electronics, cabling, and read-out devices. Please address how independence of these components of the primary and back-up channels is achieved through the application of independent power sources, physical and spatial separation, independence of signals sent to the location(s) of the read-out devices, and the independence of the displays.

3.S Power supplies The OIP states, in part, that:

Both channels will be powered from dedicated batteries and local battery chargers. The battery chargers for both channels will normally be powered from separate sources of 120V AC power. Minimum battery life of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> will be provided. The battery systems will include provision for battery replacement should the battery charger be unavailable following the event. Spare batteries will be readily available. In the event of a loss of normal power the battery chargers could be connected to another suitable power source.

RAI-S a) A description of the electrical AC power sources and capacities for the primary and backup channels battery charger.

b) If the level measurement channels are to be powered through a battery system (either directly or through an Uninterruptible Power Supply), please provide the design criteria that will be applied to size the battery in a manner that ensures, with margin, that the channel will be available to run reliably and continuously following the onset of the BDB event for the minimum duration needed, consistent with the plant mitigation strategies for BDB external events (Order EA-12-049).

3.S Accuracy The OIP states, in part, that:

Instrument channels will be designed such that they will maintain their design accuracy following a power interruption or change in power source without recalibration.

Accuracy will consider SFP conditions, e.g., saturated water, steam environment, or concentrated borated water. Additionally, instrument accuracy will be

- 6 sufficient to allow trained personnel to determine when the actual level exceeds the specified lower level of each indicating range (Levels 1, 2 and 3) without conflicting or ambiguous indication. The accuracy will be within the resolution requirements of Figure 1 of NEI-12-02.

RAI-7

Please provide the following:

a) An estimate of the expected instrument channel accuracy performance (e.g., in percentage of span) under both a) normal SFP level conditions (approximately Level 1 or higher) and b) at the SDS conditions (i.e., radiation, temperature, humidity, post-seismic and post-shock conditions) that would be present if the SFP level were at the Level 2 and Level 3 datum points.

b) A description of the methodology that will be used for determining the maximum allowed deviation from the instrument channel design accuracy that will be employed under normal operating conditions as an acceptance criterion for a calibration procedure to flag to operators and to technicians that the channel requires adjustment to within the normal condition design accuracy.

3.7 Testing The OIP states, in part, that:

Instrument channel design will provide for routine testing and calibration consistent with Order EA-12-051 and the guidance in NEI 12-02. Details will be determined during the engineering and design phase. Instrument channel testing and calibration will be performed using existing plant work control processes.

RAI-8

Please provide the following:

a) A description of the capability and provisions the proposed level sensing equipment will have to enable periodic testing and calibration, including how this capability enables the equipment to be tested in situ.

b) A description of how such testing and calibration will enable the conduct of regular channel checks of each independent channel against the other, and against any other permanently-installed SFP level instrumentation.

c) A description of how calibration tests and functional checks will be performed and the frequency at which they will be conducted. Discuss how these surveillances will be incorporated into the plant surveillance program.

d) A description of what preventative maintenance tasks are required to be performed during normal operation, and the planned maximum surveillance interval that is

- 7 necessary to ensure that the channels are fully conditioned to accurately and reliably perform their functions when needed.

3.8 Display The OIP states, in part, that:

The design will include remote indication that will be accessible during post-event conditions.

RAI-9

Please provide the following:

a) The specific location for the primary and backup instrument channel display.

b) Since both the primary and backup display locations are not in the main control room, please provide a description of the location for the primary and back up displays, including primary and alternate route evaluation, habitability at display location(s), continual resource availability for personnel responsible to promptly read displays, and provisions for communications with decision makers for the various SFP drain-down scenarios and external events.

c) The reasons justifying why the locations selected will enable the information from these instruments to be considered "promptly accessible." Include consideration of various drain-down scenarios.

4.0 PROGRAM FEATURES 4.1 Procedures The OIP states, in part, that:

Procedures will be developed using guidelines and vendor instructions to address the maintenance, operation, and abnormal response issues associated with the new SFP instrumentation.

RAI-10

Please provide the following:

a) A list of the operating (both normal and abnormal response) procedures, calibration/test procedures, maintenance procedures, and inspection procedures that will be developed for use of the SFP instrumentation in a manner that addresses the order requirements.

b) A brief description of the specific technical objectives to be achieved within each procedure. If your plan incorporates the use of portable spent fuel level monitoring components, please include a description of the objectives to be achieved with

- 8 regard to the storage location and provisions for installation of the portable components when needed.

4.2 Testing and Calibration The OIP states, in part, that:

Processes will be established and maintained for scheduling and implementing necessary testing and calibration of the primary and backup spent fuel pool level instrument channels to maintain the instrument channels at the design accuracy. Testing and calibration of the instrumentation will be consistent with vendor recommendations and any other documented basis. Calibration will be specific to the mounted instrument and the monitor.

RAI-11

Please provide the following:

a) Further information describing the maintenance and testing program the licensee will establish and implement to ensure that regular testing and calibration is performed and verified by inspection and audit to demonstrate conformance with design and system readiness requirements. Include a description of your plans for ensuring that necessary channel checks, functional tests, periodic calibration, and maintenance will be conducted for the level measurement system and its supporting equipment.

b) A description of how the guidance in NEI 12-02 Section 4.3 regarding compensatory actions for one or both non-functioning channels will be addressed.

A description of the compensatory actions to be taken in the event that one of the instrument channels cannot be restored to functional status within 90 days.

July 16, 2013 Mr. Mano Nazar Executive Vice President and Chief Nuclear Officer Florida Power and Light Company P.O. Box 14000 Juno Beach, Florida 33408-0420 SUB~IECT:

ST. LUCIE NUCLEAR POWER PLANT, UNITS 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING OVERALL INTEGRATED PLAN FOR RELIABLE SPENT FUEL POOL INSTRUMENTATION (TAC NOS. MF0090 AND MF0091)

Dear Mr. Nazar:

By letter dated February 28, 2013, Florida Power & Light Company submitted an Overall Integrated Plan in response to the March 12, 2012, Commission Order modifying licenses with regard to requirements for Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051) for St. Lucie Nuclear Power Plant, Units 1 and 2. The NRC staff is reviewing your submittal and has determined that additional information is required to complete the reviews. The specific information requested is addressed in the enclosure to this letter. This request was communicated to Mr. Ken Frehafer of your staff, and based on Mr. Frehafer's e-mail dated July 9, 2013, a response would be provided by August 1, 2013. If any part of this information is not available by such date, please provide the date this information will be submitted.

Should you have any questions, please feel free to contact me at 301-415-1564.

Sincerely, IRA!

Siva P. Lingam, Project Manager Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-335 and 50-389

Enclosure:

Request for Additional Information cc w/enclosure: Distribution via Listserv DISTRIBUTION:

PUBLIC RidsLABClayton RidsAcrsAcnwMailCenter LPL2-2 RtF C. Roque-Cruz, NRR RidsNrrDssSbpb RidsNrrPMStLucie M. Waterman, RES RidsNrrDeEicb R. Rodriguez, NRR RidsRgn2MailCenter J. Evans, NRR ADAMS A ccesslon N0.: ML13196A079

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SLingam BClayton JPoole SLingam DATE 07/15/13 07/15/13 07/15/13 07/16/13 07/16/13 OFFICIAL AGENCY COPY