LIC-13-0011, Spent Fuel Pool Instrumentation Overall Integrated Plan

Spent Fuel Pool Instrumentation Overall Integrated Plan

ML13059A268
Person / Time
Site:	Fort Calhoun
Issue date:	02/28/2013
From:	Cortopassi L Omaha Public Power District
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
LIC-13-0011
Download: ML13059A268 (12)

Text

444 South 16th Street Mall Omaha, NE 68102-2247 LIC-13-0011 February 28, 2013 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001

References:

1. Docket No. 50-285

2. NRC Order Number EA-12-051, Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation, dat ed March 12, 2012 (ML12056A044) (NRC-12-0023)

3. NEI 12-02, Revision 1, Industr y Guidance for Compliance with NRC Order EA-12-051, To Modify Licenses with Regard t o Reliable Spent Fuel Pool Instrumentation, dated August 2012 (ML12240A307)

4. NRC Interim Staff Guidance, JLD-ISG-2012-03, Compliance with Order EA-12-051, Reliable Spen t Fuel Pool Instrumentation, Revision 0, da ted August 29, 2012 (ML12221A339)

5. Letter from OPPD (L. P. Cortopassi) to NRC (Document Control Desk),

OPPD Initial Status Report in Re sponse to March 12, 2012 Commission Order Modifying Licenses with Reg ard to Requ irements for Reliable S pent Fuel Pool Instrumentation (Order Number EA-12-051), dated October 27, 2012 (ML12305A311) (LIC-12-0155)

SUBJECT:

Fort Calhoun Station Spent Fuel Pool Instrumentation Overall Integrated Plan On March 12, 2012, the Nuclear Re gulatory Commission (NRC) issued an Order (Reference 2) to all power reactor licensees and holders of construction permits in a ctive or def erred status.

The Order was immedi ately effective and requires the Omaha Public Power District (OPPD) t o have a reliable indica tion of the water level in F ort Calhoun Stations spent fuel st orage pool.

Specific requirements for such indication are described in Attachment 2 of the Order. The Order also requires that an overall integra ted plan for achieving compliance with these requirements be submitted by February 28, 2013. OPPDs overall integrated plan is attached.

The Nuclear Energy Institute (NEI) has provid ed guidance (Reference 3) to the industry for compliance with the Order. The NEI guidance was endorsed by the NRC (with exc eptions and clarifications) in the Interim Staff Guidance (ISG) (Reference 4), w hich describes methods acceptable to the NRC for complying with the Order.

OPPD has received the ISG and h as developed its overall integrated plan in acco rdance with the Orders guidance for reliable indication of water level in the spent fuel storage pool.

Employment with Equal Opportunity

U. S. Nuclear Regulatory Commission LlC-13-0011 Page 2 Reference 5 provided OPPD's initial status report regarding mitigation strategies. The attached plan is based on conceptual design information. Final design details and associated procedure guidance, as well as any revisions to the information contained in the attachment, will be provided in the 6-month updates required by the Order.

If you should have any questions regarding this submittal, please contact Mr. Bill R. Hansher at (402) 533-6894.

No regulatory commitments are contained in this submittal.

I declare under penalty of perjury that the foregoing is true and correct. Executed on February 28, 2013.

Louis P. Cortopassi Site Vice President - CNO LPC/JKG/mle

Attachment:

Fort Calhoun Station Overall Integrated Plan with Regard to Reliable Spent Fuel Pool Instrumentation c: E. J. Leeds, Director of Office of Nuclear Reactor Regulation E. E. Collins, Jr., NRC Regional Administrator, Region IV L. E. Wilkins, NRC Project Manager J. M. Sebrosky, NRC Project Manager J. C. Kirkland, NRC Senior Resident Inspector

LIC-13-0011 Attachment Page 1 Fort Calhoun Station Overall Integrated Plan with Regard to Reliable Spent Fuel Pool Instrumentation I. Introduction The Nuclear Regulatory Co mmission (NRC) issued Order EA-12-05 1, Issuance of Order t o Modify Licenses with Regard to Re liable Spent Fuel Pool Instrumentation, (Reference 1) on March 12, 2012. The Order requires licenses t o have a rel iable indication of the water level in associated spent fuel storage pools capable o f supporting identification of the following pool water level conditions by trained personnel: (1) level that is adequate to support operation of the normal fuel pool coolin g system, (2) level that is adequa te to provide substantial radiation shielding for a person st anding on the spent fuel pool operating deck, and (3) level where fuel remains covered and actions to implement make-up water addition should no longer be deferred. T he Order also requires the submittal of an overall integrated plan that provides a description of how the requirements of the Order will be achieved.

NEI 12-02, Industry Guidance for Compliance with NRC Order EA-12-051, To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation, (Reference 3) provides an approach for complying with Order EA-12-051. The NRC Interim Staff Guidance (ISG), JLD-ISG-2012-03, Compliance with Order EA-12-051, Reliable Spent Fuel Pool Instrumentation , (Reference 2) considers that the methodologies and guidance in conformance with the guidelines provided in NEI 12-02, Revision 1, subject to the clar ifications and exceptions specific to Section 3.4, Qualification, are an acceptable means of meeting the requirements of Order EA-12-051.

This overall integrated plan provides the Fort Calhoun Station (FCS) approach f or complying with Order EA-12-051 using the methods descr ibed in NRC JLD-ISG-2012-03. The current revision of the Fort Calhoun Statio n Overall Integrated Plan is based on our conceptual desig n information and will be revised as we proceed with detailed design engineering. Consistent with the requirements of Order EA-12-051 and the guidance in NEI 12-02, our six-month reports will delineate progress made, any prop osed changes in our compliance methods, updates to the schedule, and if needed, requests for relief and the bases.

II. Schedule Installation of reliable spent fuel po ol level instr umentation is schedu led to be completed two refueling outages after FCS starts up from its current shutdo wn, which would be prio r to startup from Refueling Outage (28) scheduled to begin in the spring of 2016. This is an up date of the schedule provided in Reference 4 based on the anticipat ed startup date from t he current shutdown.

The following milestone schedule is provided. The dates are planning dates subject to change as design and implementation details are developed. Any changes to the following target dates will be reflected in the subsequent 6-month status reports.

LIC-13-0011 Attachment Page 2 The current milestones are:

Commence Engineering and Design 3Q 2013 Complete Design 2Q 2015 Receipt of Spent Fuel Pool (SFP) Instruments 3Q 2015 Complete Functional Test of SFP Instruments 1Q 2016 SFP Instrument Operational and Training complete 2Q 2016 III. Identification of Spent Fuel Pool Water Levels Key spent fuel pool water levels:

1. Level adequate to support operation of the normal fuel pool c ooling system -

Indicated level on either the primary or ba ckup instrument channel will be approximately elevation 1034.6 (existing low level alarm LIA-2846, 39.1 feet above po ol floor) plus the accuracy of the SFP le vel instrument channel and the current LIA-2846 low water leve l alarm. The Level 1 ele vation is approximately 2 3 feet above the lowest spent fuel pool cooling suction line, and is a conservative elevation that has been established above the lowest spent fuel pool cooling suction line. T he exact elevation for Level 1 will be determined during the d etailed design and engineering phase, but will be approximately the same as the low-level alarm elevation of the current LIA-2846 instrument.

2. Level adequate to provide substantial radiation shielding for a person standing on the spent fuel pool op erating deck - Indicate d level on e ither the primary or bac kup instrument channel will be approximately elevation 1020 plus the accuracy of the SFP level instrument channel, which is to be determined. Th is elevation is approximately 10 above the top of the spent fuel storage racks (Reference 7). The top of the spent fuel storage racks is approx imately at elevation 1009-7 (per Reference 7). The top of th e active fuel area is approximately elevation 1007-5 and as such a pproximately an additional 2.5 of water shielding is available through setting the Level 2 elevation at 1020. The Level 2 elevation of 1020 is approximately 12-7 above the top of the active fuel. This water level should provide substa ntial radiation shielding for personnel to respond to Beyond-Design-Basis external events and initiate an y SFP ma keup strategies.

3. Level where fuel rema ins covered - Indicated level on e ither the primary or backup instrument channel will be approximately elevation 1011 (approximately one foot a bove the top of the highest spent fuel r ack) plus th e accuracy of the SFP level instrument channel, which is to be determined. This elevat ion is approximately 1 above the top of the spent fuel rack. Th is monitoring level assures that there is adequate water level above the stored fuel seated in the rack. Se tting Level 3 elevation at 1011 provides a water level of approximately 3.5 over the top of the active fuel region.

LIC-13-0011 Attachment Page 3 IV. Instruments Design of the instruments will be consistent with the guidelines of NRC JLD-ISG-2012-03 an d NEI 12-02 as discussed below.

Primary and backup instrument channels will consist of fixed components. The pla n is for both channels to utilize guided wave radar, which functions according to the principle of time domain reflectometry (TDR). A generated pulse of electromagnetic energy travels down the probe.

Upon reaching the liquid surface, the pulse is reflected and based upon reflection times level is inferred. Guided wave radar attributes:

The guided wave radar assembly is a fixture lo cated close to the o perating level f loor that suspends the probe into the pool. The guid ed wave radar assembly is small and as such is easier to protect from event-generated missiles or falling objects.

Guided wave radar is effectively immune to i nterference as the signal stays in the immediate vicinity. De tails regarding probe signal and transmission of signal will be included in the design and engineering phase of the project. It is unkno wn at this point in time if any wireless components will be utili zed to transmit signals. This information will be provided in the six-month updates.

The technology is immune to the changes in t emperature or the specific gravity of the SFP water.

The technology is capable of high resolution over the length of the probe.

Measured range will be continuous over the range of the le ngth of the probe starting at normal operating level.

Primary instrument channel level sensing com ponents will be located in the northeast corner of the SFP. Backup instrument channel level sensing components will be located in the southwest corner of the SFP. See Plan View of SFP Showing New SFP Level Instrum entation in Section XVIII, Drawings.

V. Reliability Reliability of the primary and backup instrument channels wil l be assured by conformance with the guidelines of NRC JLD-ISG-2012-03 and NE I 12-02, as discussed in Section IX, Qualification. Reliable level indication will be provided whenever water and fuel are in the p ool consistent with Section XIII, Testing.

VI. Instrument Channel Design Criteria Instrument channel design criter ia will be consist ent with the guidelines of NRC JLD-ISG-2012-03 and NEI 12-02.

The guided wave radar probes will be designed and installed to be consistent with guidelines of NRC JLD-ISG-2012-03 and NEI 1 2-02. Spe cifics about the design of the pro bes will be

LIC-13-0011 Attachment Page 4 provided in the 6-month update. F CS continues to work w ith the Util ity Services Alliance for procurement of this technology.

Boron deposits are not expected to adversely impact probe performance. Period ic cleaning of deposits on the probe at the air-water interface will be determined during the eng ineering and design phase. Discussions with t he guided wave technology vend or in regards to boron deposits have been initiated and details for any maintenance will be provided in FCS procedures upon installation of the probes.

The remaining design requirements will be met t hrough the selection of the probes and through the engineering and design phase.

VII. Arrangement SFP level probes are p roposed to be installed in the southwest and northeast corners of th e SFP (diagonally opposite corners). Details of the probe locations will be finalized in the design and engineering phase. Details related to location of the tra nsmitters and the cablin g have not been finalized at this point in time and will be part of the design and engineering phase of the project.

Supports for the probes will be d esigned to shield the components from event-generate d missiles. In the conceptual design, the SFP probes bolt to a mounting plate for in stallation at the corner of the SFP, or a plate for mounting n ear the side of the SF P. This moun ting option will allow the probe to be installed within a few inches of th e SFP liner, minimizing the chances of interference with other structures, and occupying limited space on the SFP d eck. To the greatest extent possible , the suppor ts will allow the fuel-handling machine to pa ss over them without interference. Details of the supports will be addressed in the design and engineering phase of th e project. The location of the pr obes will n ot interfere with fuel ca sk handling transfers.

Cabling for power supplies and indications for each channel will be routed in separate conduits from cabling for the other channels.

Planned locations for SFP level displays will be in a mild environment of the Auxiliary Building providing adequate protection from temperature, humidity, and radiation. Preliminarily, one channel will be located in a remote location in the Ventilation Equip ment Room near FLEX strategy equipment, and one SFP level displa y is to be mounted in the Alternate Shutdown Panel in th e Upper Electrical Penetration R oom. Both location s have ready access by operators.

VIII. Mounting Both the primary and b ackup system will be installed as Seismic Class I to meet the NRC JLD-ISG-2012-03 and NEI 12-02 guidance requirements.

LIC-13-0011 Attachment Page 5 IX. Qualification Both channels will be reliable at temperature, humidity, and radiation levels consistent with the spent fuel pool water at saturation conditions for an extended period. Post event temperature at probes located above th e SFP is as sumed to b e 212°F. Post event h umidity in th e Auxiliary Building near and above the SFP is assumed to be 100% w ith condensing steam. Equipment will be qualified for expected condit ions at the i nstalled location assuming that normal power is unavailable and that the SFP has been at saturation for an extended period. Equipment located in the vicinity of the SFP will be qu alified to withstand peak and total i ntegrated dose radiation levels for its installed location assuming that post event SFP water level is equal to SFP Level 3 for an extended period.

Instrument channel reli ability will b e demonstrated via an appropriate combination of design, analyses, operating experience, and/or testing of channel components for the following sets of parameters:

conditions in the area of instru ment channel component use f or all instrument components, effects of shock and vibration on all instrument channel components, and seismic effects on instrument channel components used during and following a potential seismic event for only installed components.

Augmented quality requirements, similar to those applied to fire protection, will be applied to this project.

Temperature, humidity, and radiation levels consist ent with conditions in the vicinity of the SFP and the are a of use considering normal operational, event and post-e vent conditions for no fewer than seven days post-event will be ad dressed in the engineering and de sign phase.

Examples of post-event (beyond-design-basis) conditions that will be considered are:

radiological conditions for a normal refueling quantity of fuel in the pool.

temperatures of 212°F and 100% relative humidity environment, boiling water and/or steam environment, a concentrated borated water environment.

Components of the inst rument channels will b e qualified f or shock an d vibration using one o r more of the following methods:

Components are supplied by man ufacturers using commercial qualit y programs with shock and vibration requirements included in the purchase spe cification at levels commensurate with portable hand-held device or transportation applications; Components have a substantial hi story of operational rel iability in e nvironments with significant shock and vibration loading, such as portable hand-held device or transportation applications; or Components are inherently resistant to shock and vibration loadings, such as cables.

LIC-13-0011 Attachment Page 6 For seismic effects on instrument channel components used after a po tential seismic event for only installed components (with the exception of battery chargers and replaceable batteries), the following measures will be used to verify that the design and installation is adequate. Applicable components of the instrument channels are rated by the manufacturer (or otherwise tested) for seismic effects at levels commensurate with th ose of postulated design basis event condit ions in the area of instrument channel component use using one or more of the following methods:

demonstration of sei smic motion will be consistent with th at of existin g design b asis loads at the installed location; substantial history of operational r eliability in environment s with significant vibrat ion, such as for portable hand-held devices or tran sportation applications. Such a vibration design envelope will be inclusive of the effects of seismic motion imparted to the components proposed at the location of the proposed installation; adequacy of seismic de sign and installation is demonstrated based on the guidance in IEEE Standard 344-2004, IEEE Recommended Practice f or Seismic Qualification of Class 1E Equip ment for Nuclear Power Ge nerating Stations, (Reference 5) or a substantially similar industrial standard; demonstration that pro posed devices are su bstantially similar in de sign to models that have been previously tested for seismic effects in excess of the plant design basis at the location where the instrument is to be installed (g-levels and frequency ranges); or seismic qualification using seismic motion consistent with that of existing design basis loading at the installation location.

The procurement specification for th e probes has specif ied that the probes are to be evaluated to two times safe shutdown earthquake requirements.

X. Independence The primary and backu p instrument channels are of the same technology, are permanently installed, separated by distance and utilize independent power supplies.

XI. Power Supplies The two instrumentation channels w ill each be powered normally by a separate power supply and will have dedicated batteries and local battery chargers. Minimu m 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 b attery systems will inclu de provision for battery replacement should the battery charger be unavailable foll owing the event. Spare batteries will be available. In th e event of a l oss of normal power, the battery ch argers could be connected to another suitable power source.

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

LIC-13-0011 Attachment Page 7 Accuracy will consid er SFP conditions, e. g., saturated water, steam environment, or concentrated borated water. Additionally, instrument accuracy will be sufficient to allow trained personnel using plant procedures to determine when the actual level exceeds th e specified lower level of each ind icating 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.

XIII. Testing Instrument channel design will provide for routine testing and calibratio n consistent with Order EA-12-051 and the guidance in NEI 12-02.

XIV. Display Remote indication will be provided in the alternate safe shutdown panel in the Auxiliary Building Upper Electrical Penetration Room. The other remote indication will be provided wi th portable equipment located near FLEX equipment along the north wall of the Ventilation Equipment Room. It has not been determined at this point in time if a readout will be provided in the control room or with the plant computer display system. That de termination will be mad e during th e design and engineering phase.

The display in the alternate shutdown panel Upper Electrical Penetration Room will be:

promptly accessible to the appropriate plant st aff giving appropriate consideration to various drain down scenarios, outside of t he area surrounding the SFP floor, e.g., an appropriate distance fro m the radiological sources resulting from an event impacting the SFP, inside a structure providing protection against adverse weather, and outside of a ny very high radiation areas or LOCKED HIGH RAD AREA during normal operation.

Each instrument channel (Primary and Backup) will have the capability to dri ve an external remote 4 - 20 milliam p (ma) loop that can b e used to provide level indica tion at a se cond display location or be used as an input to the plant computer. Failure of the external remote 4 -

20 ma signal will not adversely impact the primary display located in the transmitter (electronics) enclosure.

XV. Instrument Channel Program Criteria Instrument channel program criteria will be consistent wit h the guidelines of NRC JLD-ISG-2012-03 and NEI 12-02.

LIC-13-0011 Attachment Page 8 A. Training FCS training programs and proce sses will b e used to identify the population to be trained and to determine both the initial and continuing elements of the required training.

Training will be completed prior to placing the instrumentation in service.

B. Procedures Procedures will be deve loped using guidelines and vendor instructions to address the maintenance, operation, and abnormal response issue s associated with the new SFP instrumentation consistent with NEI 12-02.

Procedures will address a strategy to ensure SFP water level addition is initiated at an appropriate time consistent with implementation of NEI 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide (Reference 6). The details of the procedure implementation will be linked to NRC Order 12-049, Issuance of Order to Modify Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Reference 8). Procedures will address the following situations:

If, at the time of an event or thereaf ter until the unit is returned to normal service, an instrument channel ceases to function, its function will be recovered within a period of time consistent with the emergency conditions t hat may apply at the time.

If, at the time of an event or thereaf ter until the unit is returned to normal service, an instrument channel component must be replaced, we may use commercially available components that may or may not meet all of the qualifications (Section IX) to maintain the instrument channel functionality.

C. Testing and Calibration Processes will be est ablished and maintained for scheduling a nd implementing necessary testing and calibration of the primary and ba ckup spent fuel pool level instrument channels to maintain t he instrument channels at the d esign accuracy.

Testing and calibration of the instrumentation will b e consistent with vendor recommendations and any other d ocumented basis. Calibration will be specific t o the mounted instrument and the monitor.

XVI. Need for Relief and Basis FCS is not requesting re lief from the requirements of Order EA-12-051 or the guidance in NRC JLD-ISG-2012-03 at this time.

Consistent with the requirements of Order EA-12-051 and the guidance in NEI 12- 02, our six-month reports will delineate progress made, any proposed changes in our compliance methods, updates to the schedule, and if needed, requests for relief and their bases.

LIC-13-0011 Attachment Page 9 XVII. References

1) EA-12-051, Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation, March 12, 2012 (ML12056A044) (NRC-12-0023)

2) NRC ISG JLD-ISG-201 2-03, Compliance with Order EA-12-051, Reliable Spent Fuel Pool Instrumentation, Revision 0, August 29, 2012 (ML12221A339)

3) NEI 12-02, Industry Guidance for Compliance with NRC Order EA-1 2-051, To Modify Licenses with Regard to Reliable Spent Fuel Pool I nstrumentation, Revision 1, August 2012 (ML12240A307)

4) Letter from OPP D (L. P. Cortopassi) to NRC (Document Control Desk), OPPD I nitial Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requir ements for Reliable S pent Fuel Pool Instrumentation (Order Number EA-12-051), October 27, 2012 (ML12305A311) (LIC-12-0155)

5) IEEE Standard 344-2004, IEEE Recommende d Practice f or Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations

6) NEI 12-06, Diverse a nd Flexible Coping Strategies (FLEX ) Implementation Guide, August 2012 (ML12242A378)

7) Letter from NRC (S. Bloom) to OPPD (T. L. Patterson), Fort Calhoun Station, Unit No. 1

- Amendment No. 155 to Facility Operating License No. DPR-40 (T AC No. M85116),

August 12, 1993 (NRC-93-0293)

8) EA-12-049, Order Modifying Licenses With Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis Exte rnal Events, Ma rch 12, 201 2 (ML12056A045)

(NRC-12-0020)

LIC-13-0011 Attachment Page 10 XVIII. Drawings Plan View of SFP Showing New SFP Level Instrumentation XIX. Open Items Fort Calhoun Station has identified no open items related to the Spen t Fuel Po ol Instrumentation Overall Integrated Plan submittal.