ML13308C188

Interim Staff Evaluation and Request for Additional Information Regarding the Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation

ML13308C188
Person / Time
Site:	Three Mile Island
Issue date:	11/13/2013
From:	John Hughey Plant Licensing Branch 1
To:	Pacilio M Exelon Nuclear
Hughey J
References
EA-12-051, TAC MF0866
Download: ML13308C188 (28)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 November 13, 2013 Mr. Michael J. Pacilio President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

THREE MILE ISLAND NUCLEAR STATION, UNIT 1 -INTERIM STAFF EVALUATION AND REQUEST FOR ADDITIONAL INFORMATION REGARDING THE OVERALL INTEGRATED PLAN FOR IMPLEMENTATION OF ORDER EA-12-051, RELIABLE SPENT FUEL POOL INSTRUMENTATION (TAC NO. MF0866)

Dear Mr. Pacilio:

On March 12, 2012, the U.S. Nuclear Regulatory Commission (NRC) issued Order EA-12-051, "Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation" (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12054A679), to all power reactor licensees and holders of construction permits in active or deferred status. This order requires the licensee to have a reliable indication of the water level in associated spent fuel storage pools capable of 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 cooling system, (2) level that is adequate to provide substantial radiation shielding for a person standing 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.

By letter dated February 28, 2013 (ADAMS Accession No. ML13063A540), Exelon Generation Company, LLC (the licensee) provided the Overall Integrated Plan (OIP) for Three Mile Island Nuclear Power Station, Unit 1, describing how it will achieve compliance with Attachment 2 of Order EA-12-051 by fall 2015. By letter dated June 26, 2013 (ADAMS Accession No. ML13176A470), the NRC staff sent a Request for Additional Information (RAI) to the licensee.

The licensee provided supplemental information by letters dated July 24, 2013 (ADAMS Accession No. ML13205A305) and August 28, 2013 (ADAMS Accession No. ML13241A036).

The NRC staff has reviewed these submittals with the understanding that the licensee will update its OIP as implementation of the Order progresses. With this in mind, the staff has included an interim staff evaluation with this letter to provide feedback on the OIP. The staff's findings in the interim staff evaluation are considered preliminary and will be revised as the OIP is updated. As such, none of the staff's conclusions are to be considered final. A final NRC staff evaluation will be issued after the licensee has provided the information requested.

The interim staff evaluation also includes RAis, response to which the NRC staff needs to complete its review. The licensee should provide the information requested in the 6-month status updates, as the information becomes available. However, the staff requests that all

M. Pacilio information be provided by March 31, 2015, to ensure that any issues are resolved prior to the date by which the licensee must complete full implementation of Order EA-12-051. The licensee should adjust its schedule for providing information to ensure that all this information is provided by the requested date.

If you have any questions regarding this letter, please contact me at 301-415-3204 or via e-mail at john.hughey@nrc.gov.

Sincerely, ftiJ;/Jr John D. Hughey, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-289

Enclosure:

Interim Staff Evaluation and Request for Additional Information cc w/encl: Distribution via Listserv

INTERIM STAFF EVALUATION AND REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO THE OVERALL INTEGRATED PLAN IN RESPONSE TO ORDER EA-12-051, RELIABLE SPENT FUEL POOL INSTRUMENTATION EXELON GENERATION COMPANY, LLC THREE MILE ISLAND NUCLEAR POWER STATION, UNIT 1 DOCKET NO. 50-289

1.0 INTRODUCTION

On March 12, 2012, the U.S. Nuclear Regulatory Commission (NRC) issued Order EA-12-051, "Issuance of Order to Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation" (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12054A679), to all power reactor licensees and holders of construction permits in active or deferred status. This order requires, in part, that all operating reactor sites have a reliable means of remotely monitoring wide-range Spent Fuel Pool (SFP) levels to support effective prioritization of event mitigation and recovery actions in the event of a Beyond-Design-Basis (BOB) external event. The order required all holders of operating licenses issued under Title 10 of the Code of Federal Regulations (10 CFR) Part 50, "Domestic Licensing of Production and Utilization Facilities," to submit to the NRC an Overall Integrated Plan (OIP) by February 28, 2013.

By letter dated February 28, 2013 (ADAMS Accession No. ML13063A540), Exelon Generation Company, LLC (the licensee) provided the OIP for Three Mile Island (TMI) Nuclear Power Station, Unit 1, describing how it will achieve compliance with Attachment 2 of Order EA-12-051 by fall2015. By letter dated June 26, 2013 (ADAMS Accession No. ML13176A470), the NRC staff sent a Request for Additional Information (RAI) to the licensee. The licensee provided supplemental information by letters dated July 24, 2013 (ADAMS Accession No. ML13205A305) and August 28, 2013 (ADAMS Accession No. ML13241A036).

2.0 REGULATORY EVALUATION

Order EA-12-051 requires all holders of operating licenses issued under 10 CFR Part 50, notwithstanding the provisions of any Commission regulation or license to the contrary, to comply with the requirements described in Attachment 2 to the Order except to the extent that a more stringent requirement is set forth in the license. Licensees shall promptly start implementation of the requirements in Attachment 2 to the Order and shall complete full implementation no later than two refueling cycles after submittal of the OIP or December 31, 2016, whichever comes first.

Order EA-12-051 required the licensee, by February 28, 2013, to submit to the Commission an OIP, including a description of how compliance with the requirements described in Attachment 2 of the Order will be achieved.

Enclosure

Attachment 2 of Order EA-12-051 requires the license to have a reliable indication of the water level in associated spent fuel storage pools capable of 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 cooling system, (2) level that is adequate to provide substantial radiation shielding for a person standing on the SFP operating deck, and (3) level where fuel remains covered and actions to implement make-up water addition should no longer be deferred. of Order EA-12-051, states that the SFP level instrumentation shall include the following design features:

1.1 Instruments

The instrumentation shall consist of a permanent, fixed primary instrument channel and a backup instrument channel. The backup instrument channel may be fixed or portable. Portable instruments shall have capabilities that enhance the ability of trained personnel to monitor spent fuel pool water level under conditions that restrict direct personnel access to the pool, such as partial structural damage, high radiation levels, or heat and humidity from a boiling pool.

1.2 Arrangement

The spent fuel pool level instrument channels shall be 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 spent fuel pool. This protection may be provided by locating the primary instrument channel and fixed portions of the backup instrument channel, if applicable, to maintain instrument channel separation within the spent fuel pool area, and to utilize inherent shielding from missiles provided by existing recesses and corners in the spent fuel pool structure.

1.3 Mounting

Installed instrument channel equipment within the spent fuel pool shall be mounted to retain its design configuration during and following the maximum seismic ground motion considered in the design of the spent fuel pool structure.

1.4 Qualification

The primary and backup instrument channels shall be reliable at temperature, humidity, and radiation levels consistent with the spent fuel pool water at saturation conditions for an extended period.

This reliability shall be established through use of an augmented quality assurance process (e.g., a process similar to that applied to the site fire protection program).

1.5 Independence

The primary instrument channel shall be independent of the backup instrument channel.

1.6 Power supplies: Permanently installed instrumentation channels shall each be powered by a separate power supply. Permanently installed and portable instrumentation channels shall provide for power connections from sources independent of the plant [alternating current (ac)] and [direct

current (de)] power distribution systems, such as portable generators or replaceable batteries. Onsite generators used as an alternate power source and replaceable batteries used for instrument channel power shall have sufficient capacity to maintain the level indication function until offsite resource availability is reasonably assured.

1. 7 Accuracy: The instrument channels shall maintain their designed accuracy following a power interruption or change in power source without recalibration.

1.8 Testing

The instrument channel design shall provide for routine testing and calibration.

1.9 Display

Trained personnel shall be able to monitor the spent fuel pool water level from the control room, alternate shutdown panel, or other appropriate and accessible location. The display shall provide on-demand or continuous indication of spent fuel pool water level. of Order EA-12-051, states that the SFP instrumentation shall be maintained available and reliable through appropriate development and implementation of the following programs:

2.1 Training

Personnel shall be trained in the use and the provision of alternate power to the primary and backup instrument channels.

2.2 Procedures

Procedures shall be established and maintained for the testing, calibration, and use of the primary and backup spent fuel pool instrument channels.

2.3 Testing and Calibration: Processes shall 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.

On August 29, 2012, the NRC issued an Interim Staff Guidance (ISG) document, JLD-ISG-2012-03, "Compliance with Order EA-12-051, Reliable Spent Fuel Pool Instrumentation" (ADAMS Accession No. ML12221A339), to describe methods acceptable to the NRC staff for complying with Order EA-12-051. The ISG endorses, with exceptions and clarifications, the methods described in the Nuclear Energy Institute (NEI) guidance document NEI 12-02, Revision 1, "Industry Guidance for Compliance with NRC Order EA-12-051, 'To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation,"' dated August 2012 (ADAMS Accession No. ML12240A307). Specifically, the ISG states:

The NRC staff considers that the methodologies and guidance in conformance with the guidelines provided in NEI 12-02, Revision 1, subject to the clarifications and exceptions in Attachment 1 to this ISG, are an acceptable means of meeting the requirements of Order EA-12-051.

3.0 TECHNICAL EVALUATION

3.1 Background and Schedule TMI is a two unit pressurized-water reactor station, with Unit 2 permanently shut down. The two units share a common Fuel Handling Building (FHB). TMI, Unit 2 SFP is not in service and it is not connected to the TMI, Unit 1 SFP. Therefore, TMI, Unit 2 SFP is out of scope for this review.

The licensee's OIP was submitted on February 28, 2013. The OIP states that installation of the SFP level instrumentation at TMI, Unit 1 will be completed by fall 2015.

The NRC staff has reviewed the licensee's schedule for implementation of SFP level instrumentation. If the licensee completes implementation in accordance with this schedule, it would appear to achieve compliance with Order EA-12-051 within two refueling cycles after submittal of the OIP and before December 31, 2016.

3.2 Spent Fuel Pool Water Levels of Order EA-12-051 states, in part, that:

All licensees identified in Attachment 1 to this Order shall have a reliable indication of the water level in associated spent fuel storage pools capable of 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 cooling system [Level 1], (2) level that is adequate to provide substantial radiation shielding for a person standing on the SFP operating deck [Level 2],

and (3) level where fuel remains covered and actions to implement make-up water addition should no longer be deferred [Level 3].

NEI 12-02 states, in part, that:

Level 1 represents the HIGHER of the following two points:

• The level at which reliable suction loss occurs due to uncovering of the coolant inlet pipe, weir or vacuum breaker (depending on the design), or

• The level at which the water height, assuming saturated conditions, above the centerline of the cooling pump suction provides the required net positive suction head specified by the pump manufacturer or engineering analysis.

TMI, Unit 1 has SFP A and SFP B for storage of used fuel. The pools are normally connected via a channel and normally open gate; thus, they are operated as a common pool. The bottom of the channel is at elevation 321 feet (ft.) 0 inches (in.). The pools are normally interconnected at the same water level when the water level is greater than nominally 1 ft. 11 in. above the top of the spent fuel storage racks in SFP A, and 1 ft. 8 in. above the top of the spent fuel storage

rack in SFP B. The gate between the pools is closed for limited time periods for maintenance or non-refueling operations.

In its OIP, the licensee stated that Level 1 is the indicated level on either primary or backup instrument channel of greater than 21 ft. 0 in. (elevation 340ft. 4 in.) above the top of the storage racks. The licensee also stated that any elevation above 340ft. 4 in. will provide flow of water to fuel pool cooling system.

In its letter dated, July 24, 2013, the licensee stated, in part, that:

The TMI-1 Spent Fuel Pool has two Spent Fuel Pool Cooling Pumps that take suction from the pool with the bottom of the suction elbows (which faces downward) at the 340' elevation. Normal Spent Fuel Pool Level is at the 344' 6" and low level at 343' 6". Presently Level 1 is considered 340' 4"; however, the detailed design will include a calculation to determine adequate water level to maintain normal fuel pool cooling system operation. This information will be available following acceptance of the 100% design, scheduled in May 2014. The result will be provided in the August 2014, 6-month Integrated Plan update report to the NRC.

In its letter dated, August 28, 2013, the licensee stated in part, that:

The detailed design will include a calculation to determine adequate water level to maintain normal fuel pool cooling system operation. This information will be available following acceptance of the 100% design, scheduled in May, 2014.

The result will be provided in the August 2014, 6- month Integrated Plan update report to the NRC.

The NRC staff notes that further information regarding the identification of Level 1 is not currently available for review and that the detailed design will include a calculation to determine adequate water level to maintain normal fuel pool cooling system operation. The staff also notes that the licensee indicated that the information will be provided to the staff in the August 2014, 6-month OIP update. The staff has identified this request as:

RAI#1 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.

(This information was previously requested as RAI-1 a in the NRC letter dated June 26, 2013)

NEI 12-02 states, in part, that:

Level 2 represents the range of water level where any necessary operations in the vicinity of the spent fuel pool can be completed without significant dose consequences from direct gamma radiation from the stored spent fuel. Level 2 is based on either of the following:

• 10 feet (+/- 1 foot) above the highest point of any fuel rack seated in the spent fuel pools, or

• a designated level that provides adequate radiation shielding to maintain personnel radiological dose levels within acceptable limits while performing local operations in the vicinity of the pool. This level shall be based on either plant-specific or appropriate generic shielding calculations, considering the emergency conditions that may apply at the time and the scope of necessary local operations, including installation of portable SFP instrument channel components.

In its OIP, the licensee stated that Level 2 is the indicated level on either the primary or backup instrument channel of greater than 10ft. (elevation 329ft. 4 in.) above the top of the storage racks.

In its letter dated July 24, 2013, the licensee provided a sketch depicting the SFP elevations identified as levels 1, 2, and 3. The NRC staff reviewed this sketch and notes that Level 2 is identified at an elevation 10 ft. 3 in. above the top of the storage racks. The staff also notes that the licensee designated Level 2 using the first of the two options described in NEI 12-02 for Level2.

NEI 12-02 states, in part, that:

Level 3 corresponds nominally (i.e., +/- 1 foot) to the highest point of any fuel rack seated in the spent fuel pool. Level 3 is defined in this manner to provide the maximum range of information to operators, decision makers and emergency response personnel.

In its OIP, the licensee stated that Level 3 is the indicated level on either the primary or backup instrument channel of greater than 0 ft. (elevation 319ft. 4 in.) above the top of the storage racks.

In its letter dated July 24, 2013, the licensee provided a sketch depicting the SFP elevations identified as levels 1, 2, and 3. The NRC staff reviewed this sketch and notes that the elevation provided for Level 3 is above the highest point of any spent fuel storage rack seated in the SFP.

The licensee's proposed plan, with respect to identification of Levels 2 and 3, appears to be consistent with NEI 12-02, as endorsed by the ISG.

3.3 Design Features: Instruments of Order EA-12-051 , states, in part, that:

The instrumentation shall consist of a permanent, fixed primary instrument channel and a backup instrument channel. The backup instrument channel may be fixed or portable. Portable instruments shall have capabilities that enhance the ability of trained personnel to monitor spent fuel pool water level under

conditions that restrict direct personnel access to the pool, such as partial structural damage, high radiation levels, or heat and humidity from a boiling pool.

NEI 12-02 states, in part, that:

A spent fuel pool level instrument channel is considered reliable when the instrument channel satisfies the design elements listed in Section 3

[Instrumentation Design Features] of this guidance and the plant operator has fully implemented the programmatic features listed in Section 4 [Program Features].

In its OIP, the licensee stated, in part, that:

Primary (fixed) instrument channel: The primary instrument channel level sensing components will be located and permanently mounted in the SFP A. The primary instrument channel will provide for SFP A continuous level indication over a minimum range of approximately 26 feet from the high pool level elevation of 345' 0" to the top of the spent fuel racks at elevation 319' 1" for SFP A and to elevation 321' 0" for SFP B which is the bottom of the channel between the pools ...

Backup instrument channel: The backup instrument channel level sensing components will be located and permanently mounted in SFP B. The backup instrument channel will provide for SFP B continuous level indication over a minimum range of approximately 26 feet from the high pool level elevation of 345' 0" to the top of the spent fuel racks at elevation 319' 4" for SFP B and to elevation 321' 0" for SFP A which is the bottom of the channel between the pools ...

Regarding the configuration of the SFPs and gates, in its OIP, the licensee stated, in part, that:

In the context of NEI 12-02, the sensor located in SFP A is considered the Primary Instrument Channel for SFP A and the Backup Instrument Channel for SFP B. Similarly, the sensor located in SFP B is considered the Primary Instrument Channel for SFP B and the Backup Instrument Channel for SFP A.

Spent Fuel Pools A and B both contain spent fuel, and are interconnected by a channel and normally open gate. The bottom of the channel is at elevation 321' 0". This is 1 foot 11 inches above the top of the fuel storage racks in SFP A and 1 foot 8 inches above the top of the fuel storage racks in SFP B. With this configuration the sensor in SFP A fully meets the Primary Instrument channel level measuring requirements for SFP A. Similarly, the sensor in SFP B fully meets the Primary Instrument channel level measuring requirements for SFP B.

However, due to the depth of the interconnecting channel relative to the top of the fuel storage racks neither of these sensors, when considered as Backup Instrument Channels, will measure to the top of the fuel storage racks as defined by the parenthetical tolerance for this value given in NEI 12-02. Exelon considers this situation acceptable for the following reasons:

• NEI 12-023 describes Level 3 as nominally the highest point of any fuel rack seated in the SFP. The bottom of the connecting channel is a maximum of 1 foot 11 inches above the top of the shortest rack (elevation 321' 0"- 319' 1" =

1 foot 11 inches). Considering the overall depth of the SFP, 1 foot 11 inches is essentially the same as the +/- 1 foot tolerance suggested by NEI 12-02.

• Level 3 is described as the level where fuel remains covered and actions to implement make-up water addition should no longer be deferred. In the extremely unlikely event that water addition to the SFP was to be deferred until Level 3 is reached, in the TMI, Unit 1, interconnected pool configuration, Level 3 would be reached in SFP 8 first at elevation 319' 4". Considering the difference in time to reach Level 3 based on the top of the SFP 8 fuel racks versus the bottom elevation of the interconnecting channel at 321' 0", it would take approximately 3% less time to reach Level 3 based on the bottom of the channel. This is considered a negligible time differential.

• In all likelihood, water addition to the SFP will commence between Levels 1 and 2 and be monitored to confirm success. As such this deviation from the reference point for Level 3 (i.e., top of fuel rack or bottom of channel) is insignificant relative to any follow-up decision making.

Therefore, this configuration provides adequate monitoring for beyond-design-basis external events and catastrophic events affecting TMI, Unit 1, Spent Fuel Pools, and provides plant personnel adequate level monitoring information to effectively prioritize emergency actions.

In its letter dated July 24, 2013, the licensee provided a sketch showing the different level indications and the level sensor instrument. This sketch shows that the level sensor range for both the primary and backup instrument channels is approximately 25 ft. 11 in. from the normal water level elevation to the top of the spent fuel racks.

The NRC staff notes that the range specified for the licensee's instrumentation will cover Levels 1, 2, and 3, as described in Section 3.2 above. The licensee's proposed plan, with respect to the number of channels and the range of the instrumentation for both of its SFPs, appears to be consistent with NEI 12-02, as endorsed by the ISG.

The NRC staff has concerns regarding the effects the installation of the gate could have on the reliability of the SFP level instrumentation to meet the requirements of Order EA-12-051 when the gate between the pools is closed. The staff has identified this request as:

RAI#2 Please describe the impact of the installation of the gate on the reliability of the SFP level instrumentation for each SFP, and what compensatory measures would be taken to ensure reliable level indication in each SFP when the gate is installed.

3.4 Design Features: Arrangement of Order EA-12-051, states, in part, that:

The spent fuel pool level instrument channels shall be 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 spent fuel pool. This protection may be provided by locating the primary instrument channel and the fixed portions of the backup instrument channel, if applicable, to maintain instrument channel separation within the spent fuel pool area, and to utilize inherent shielding from missiles provided by existing recesses and corners in the spent fuel pool structure.

NEI 12-02 states, in part, that:

The intent of the arrangement requirement is to specify reasonable separation and missile protection requirements for permanently installed instrumentation used to meet this order. Although additional missile barriers are not required to be installed, separation and shielding can help minimize the probability that damage due to an explosion or extreme natural phenomena (e.g., falling or wind-driven missiles) will render fixed channels of SFP instrumentation unavailable.

Installation of the SFP instrument channels shall be consistent with the plant-specific SFP design requirements and should not impair normal SFP function.

Channel separation should be maintained by locating the installed sensors in different places in the SFP area.

In its OIP, the license stated, in part, that:

The current plan is to install SFP level sensors in the northwest corner of the SFP A and along the south wall of SFP B. These locations provide in excess of 80' of separation between the sensors. The sensors themselves will be mounted, to the extent practical, near the pool walls and below the pool curb to minimize their exposure to damaging debris and not interfere with SFP activities.

Instrument channel electronics and power supplies will be located in seismic and missile protected areas either below the SFP operating floor or in buildings other than the FHB. The areas to be selected will provide suitable radiation shielding and environmental conditions for the equipment consistent with instrument manufacturer's recommendations. Equipment and cabling for power supplies and indication for each channel will be separated equivalent to that provided for redundant safety related services.

In its letter dated July 24, 2013, the licensee stated, in part, that:

The initial concept is to locate the primary and backup level sensors at the opposite ends of the combined pool. The final locations and cable routings are not available at this time. A detailed design will include sensor locations and cable routing drawings from the Spent Fuel Pool to each channel indicator. The

current plan for the design of the SFPI [spent fuel pool instrumentation] system based on the current Exelon Nuclear program schedule for TMI-1 is to begin the design phase in October 2013 with design completion and 100% acceptance of the design in May 2014. The requested information will be provided in the August 2014, 6-month Integrated Plan update.

In its letter dated August 28, 2013, the licensee included Attachment 1 showing the proposed components and arrangement of the guided wave radar system SFP level sensor and electronics enclosure for one of the channels.

The NRC staff notes that the information regarding final sensor locations and cable routings for the SFP level instrumentation is not currently available for review and that in its letter dated August 28, 2013, the licensee identified the status of this activity as "Not Started." The licensee indicated that the information will be provided during the August 2014, 6-month OIP update.

The staff has identified this request as:

RAI#3 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 backup SFP level sensor, and the proposed routing of the cables that will extend from the sensors toward the location of the readout/display device.

(This information was previously requested as RA/-2 in the NRC letter dated June 26, 2013) 3.5 Design Features: Mounting of Order EA-12-051 states, in part, that:

Installed instrument channel equipment within the spent fuel pool shall be mounted to retain its design configuration during and following the maximum seismic ground motion considered in the design of the spent fuel pool structure.

NEI 12-02 states, in part, that:

The mounting shall be designed to be consistent with the highest seismic or safety classification of the SFP. An evaluation of other hardware stored in the SFP shall be conducted to ensure it will not create adverse interaction with the fixed instrument location(s).

The basis for the seismic design for mountings in the SFP shall be the plant seismic design basis at the time of submittal of the Integrated Plan for implementing NRC Order EA-12-051.

In its OIP, the licensee stated that the design of the mounting of the sensors in the SFP shall be consistent with the seismic Class I criteria. The licensee also stated that the installed equipment will be verified to be seismically adequate for the seismic motions associated with

the maximum seismic ground motion considered in the design of the plant area in which it is installed.

In its letter dated July 24, 2013, the licensee stated, in part, that, Device total loading and mounting will be performed as part of the detailed design process. The current plan for the design of the SFPI system based on the current Exelon Nuclear program schedule for TMI-1 is to begin the design phase in October 2013 with design completion and 100% acceptance of the design in May 2014. The requested information will be provided in the August 2014, 6-month Integrated Plan update.

The NRC staff notes that the information regarding mounting device total loading and attachments for the SFP level instrumentation is not currently available for review and that in its letter dated August 28, 2013, the licensee identified the status of this activity as "Not Started."

The licensee indicated that the information will be provided to the staff during the August 2014, 6-month OIP update. The staff has identified these requests as:

RAI#4 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.

(This information was previously requested as RAI-3 in the NRC letter dated June 26, 2013)

In addition, the staff plans to verify the final design and the results of the licensee's seismic testing and analysis report. The staff has identified these requests as:

RAI#5 For RAI 4(a) above, please provide the results of the analyses used to verify the design criteria and methodology for seismic testing of the SFP instrumentation and the

electronics units, including, design-basis maximum seismic loads and the hydrodynamic loads that could result from pool sloshing or other effects that could accompany such seismic forces.

RAI#6 For each of the mounting attachments required to attach SFP level equipment to plant structures, please describe the design inputs, and the methodology that was used to qualify the structural integrity of the affected structures/equipment.

3.6 Design Features: Qualification of Order EA-12-051 states, in part, that:

The primary and backup instrument channels shall be reliable at temperature, humidity, and radiation levels consistent with the spent fuel pool water at saturation conditions for an extended period. This reliability shall be established through use of an augmented quality assurance process (e.g. a process similar to that applied to the site fire protection program).

NEI 12-02 states, in part, that:

The instrument channel reliability shall be demonstrated via an appropriate combination of design, analyses, operating experience, and/or testing of channel components for the following sets of parameters, as described in the paragraphs below:

• conditions in the area of instrument channel component use for all instrument components,

• effects of shock and vibration on instrument channel components used during any applicable event for only installed components, and

• seismic effects on instrument channel components used during and following a potential seismic event for only installed components ...

The NRC staff assessment of the instrument qualification is discussed in the following subsections: 3.6.1, "Augmented Quality Process," and 3.6.2, "Qualification and Reliability."

3.6.1 Augmented Quality Process Appendix A-1 of the guidance in NEI 12-02 describes a quality assurance process for non-safety systems and equipment that is not already covered by existing quality assurance requirements. Within the ISG, the NRC staff found the use of this quality assurance process to be an acceptable means of meeting the augmented quality requirements of Order EA-12-051.

In its OIP, the licensee stated that the reliability of the instrumentation would be established through the use of an augmented quality assurance process (e.g., a process similar to that applied to the site fire protection program).

The licensee's proposed augmented quality assurance process appears to be consistent with the guidance.

3.6.2 Qualification and Reliability NEI 12-02 states, in part, that:

The temperature, humidity and radiation levels consistent with conditions in the vicinity of the [SFP] and the area of use considering normal operational, event and post-event conditions for no fewer than seven days post-event or until off-site resources can be deployed by the mitigating strategies resulting from Order EA-12-049 should be considered. Examples of post-event (beyond-design-basis) conditions to be considered are:

• radiological conditions for a normal refueling quantity of freshly discharged (1 00 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />) fuel with the SFP water level 3 as described in this order,

• temperatures of 212 degrees F and 100% relative humidity environment,

• boiling water and/or steam environment

• a concentrated borated water environment, and ...

In its OIP, the licensee stated, consistent with NEI 12-02, in part, that:

Temperature, humidity and radiation levels consistent with the conditions in the vicinity of the SFP and the area of use considering normal operation, event and post- event conditions for no fewer than seven days post-event or until off-site resources can be deployed by the mitigating strategies resulting from Order EA-12-049 will be addressed in the detailed design engineering phase of the project. Examples of post-event (beyond-design-basis) conditions to be considered are:

• radiological conditions for a normal refueling quantity of freshly discharged (1 00 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />) fuel with the SFP water level 3 as described in this Order EA-12-051,

• temperatures of 212 degrees F and 100% relative humidity environment,

• boiling water and/or steam environment,

• a concentrated borated water environment, and ...

Related to qualification and reliability, in its letter dated July 24, 2013, the licensee stated, in part, that:

Device qualification and reliability will be performed as part of the detailed design process. The current plan for the design of the SF PI system based on the current Exelon Nuclear program schedule for TMI-1 is to begin the design phase in October 2013 with design completion and 100% acceptance of the design in May 2014. The requested information will be provided in the August 2014, 6-month Integrated Plan update.

The NRC staff notes that the information regarding SFP level instrumentation qualification and reliability is not currently available for review and that in its letter dated August 28, 2013, the licensee identified the status of this activity as "Not Started." The licensee indicated that the information will be provided to the staff during the August 2014, 6-month OIP update. The staff has identified these requests as:

RAI#7 Please provide the following:

a) A description of the specific method or combination of methods that will be applied to demonstrate the reliability of the permanently installed equipment under 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 (i) the level sensor mounted in the SFP area, and (ii) any control boxes, electronics, or readout 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.

(This information was previously requested as RAI-4 in the NRC letter dated June 26, 2013)

In addition, the staff plans to verify the results of the licensee's testing and analysis used to demonstrate the qualification and reliability of the installed equipment when it is completed based on the licensee's response to the following RAI.

RAI#8 For RAI 7 above, please provide the results from the selected methods, tests and analyses used to demonstrate the qualification and reliability of the installed equipment in accordance with the Order requirements.

3. 6. 3 Qualification Evaluation Summary Upon acceptable resolution of the RAis in subsection 3.6.1 and 3.6.2, the NRC staff will be able to make a conclusion regarding the instrument qualification.

3.7 Design Features: Independence of Order EA-12-051 states, in part, that:

The primary instrument channel shall be independent of the backup instrument channel.

NEI 12-02 states, in part, that:

Independence of permanently installed instrumentation, and primary and backup channels, is obtained by physical and power separation commensurate with the hazard and electrical isolation needs. If plant AC or DC power sources are used then the power sources shall be from different buses and preferably different divisions/channels depending on available sources of power.

In its OIP, the licensee stated that the primary instrument channel would be independent of the backup instrument channel and that independence would be achieved through physical and electrical separation of each channels' components commensurate with hazard and electrical isolation needs.

In its July 24, 2013, letter, the licensee stated, in part, that:

Device channel independence evaluation will be performed as part of the detailed design process. The current plan for the design of the SFPI system based on the current Exelon Nuclear program schedule for TM1-1 is to begin the design phase in October 2013 with design completion and 100% acceptance of the design in May 2014. The requested information will be provided in the August 2014, 6-month Integrated Plan update.

The NRC staff notes that the information regarding SFP level instrumentation channel independence is not currently available for review and that in its letter dated August 28, 2013, the licensee identified the status of this activity as "Not Started." The licensee indicated that the information will be provided to the staff during the August 2014, 6-month OIP update for Unit 1.

The staff has identified this request as:

RAI#9 Please provide the following:

a) A description of how the two channels of the proposed level measurement system 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 on how each level measurement system, consisting of level sensor electronics, cabling, and readout devices will be designed and installed to address independence through the application and selection of independent power sources, the use of physical and spatial separation, independence of signals sent to the location(s) of the readout devices, and the independence of the displays.

(This information was previously requested as RAI-5 in the NRC letter dated June 26, 2013) 3.8 Design Features: Power Supplies of Order EA-12-051, states in part, that:

Permanently installed instrumentation channels shall each be powered by a separate power supply. Permanently installed and portable instrumentation channels shall provide for power connections from sources independent of the plant ac and de power distribution systems, such as portable generators or replaceable batteries. Onsite generators used as an alternate power source and replaceable batteries used for instrument channel power shall have sufficient capacity to maintain the level indication function until offsite resource availability is reasonably assured.

NEI 12-02 states, in part, that:

The normal electrical power supply for each channel shall be provided by different sources such that the loss of one of the channels primary power supply will not result in a loss of power supply function to both channels of SFP level instrumentation.

All channels of SFP level instrumentation shall provide the capability of connecting the channel to a source of power (e.g., portable generators or replaceable batteries) independent of the normal plant AC and DC power systems. For fixed channels this alternate capability shall include the ability to isolate the installed channel from its normal power supply or supplies. The portable power sources for the portable and installed channels shall be stored at separate locations, consistent with the reasonable protection requirements associated with NEI 12-06 (Order EA-12-049). The portable generator or replaceable batteries should be accessible and have sufficient capacity to support reliable instrument channel operation until off-site resources can be deployed by the mitigating strategies resulting from Order EA-12-049.

If adequate power supply for either an installed or portable level instrument credits intermittent operation, then the provisions shall be made for quickly and reliably taking the channel out of service and restoring it to service. For example, a switch on the power supply to the channel is adequate provided the power can be periodically interrupted without significantly affecting the accuracy and reliability of the instrument reading. Continuous indication of SFP level is acceptable only if the power for such indication is demonstrably adequate for the time duration specified in section 3.1 [.]

In its OIP, the licensee stated, in part, that:

Each channel will be normally powered from a different 120 Vac [120 volts-alternating current] bus. Upon loss of normal ac power, individual channel installed batteries will automatically maintain continuous channel operation. The batteries will be replaceable and be sized to maintain channel operation until off-site resources can be deployed by the mitigating strategies resulting from Order EA-12-0494. Additionally, each channel will have provisions for connection to another suitable power source.

In its letter dated July 24, 2013, the licensee stated, in part, that:

Device total power supply configuration will be performed as part of the detailed design process. The current plan for the design of the SF PI system based on the current Exelon Nuclear program schedule for TMI-1 is to begin the design phase in October 2013 with design completion and 100% acceptance of the design in May 2014. The requested information will be provided in the August 2014, 6-month Integrated Plan update.

The NRC staff notes that the information regarding total power supply configuration for the SFP level instrumentation is not currently available for review and that in its letter dated August 28, 2013, the licensee identified the status of this activity as "Not Started." The licensee indicated that the information will be provided to the staff during the August 2014, 6-month OIP update.

The staff has identified this request as:

RAI #10 Please provide the following:

a} A description of the electrical ac power sources and capabilities for the primary and backup channels.

b) Please provide the results of the calculation depicting the battery backup duty cycle requirements demonstrating that its capacity is sufficient to maintain the level indication function until offsite resource availability is reasonably assured.

(This information was previously requested as RAI-6 in the NRC letter dated June 26, 2013.

However, based on feedback from the licensees, it was revised as stated above.)

3.9 Design Features: Accuracy of Order EA-12-051 states, in part, that:

The instrument channels shall maintain their designed accuracy following a power interruption or change in power source without recalibration.

NEI 12-02 states, in part, that:

Accuracy should consider operations while under SFP conditions, e.g., saturated water, steam environment, or concentrated borated water. Additionally, instrument accuracy should be 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.

In its OIP, the licensee stated, in part, that:

The instrument channels will be designed to maintain their design accuracy following a power interruption or change in power source without recalibration.

Instrument channel accuracy, to be determined during detailed design, will consider SFP conditions (e.g., saturated water, steam environment, concentrated borated water), as well as, other applicable radiological and environmental conditions and include display accuracy. Instrument channel accuracy will be sufficient to allow trained personnel to determine when the actual level exceeds the specified lower level of each indicating range (levels 1, 2 or 3) without conflicting or ambiguous indications.

In its letter dated July 24, 2013, the licensee stated, in part, that:

Device channel accuracy analysis will be performed as part of the detailed design process. The current plan for the design of the SF PI system based on the current Exelon Nuclear program schedule for TMI-1 is to begin the design phase in October 2013 with design completion and 100% acceptance of the design in May 2014. The requested information will be provided in the August 2014, 6-month Integrated Plan update.

The NRC staff notes that the information regarding SFP level instrumentation channel accuracy is not currently available for review and that in its letter dated August 28, 2013, the licensee identified the status of this activity as "Not Started." The licensee indicated that the information will be provided to the staff during the August 2014, 6-month OIP update. The staff has identified this request as:

RAI #11 Please provide the following:

a) An estimate of the expected instrument channel accuracy performance under both (i) normal SFP level conditions (approximately Level 1 or higher) and (ii) at the

BOB 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.

(This information was previously requested as RAI-7 in the NRC letter dated June 26, 2013) 3.10 Design Features: Testing of Order EA-12-051 states, in part, that:

The instrument channel design shall provide for routine testing and calibration.

NEI 12-02 states, in part, that:

Static or non-active installed (fixed) sensors can be used and should be designed such that testing and/or calibration can be performed in-situ. For microprocessor based channels the instrument channel design shall be capable of testing while mounted in the pool.

In its OIP, the licensee stated that instrument channel design would provide for routine testing and calibration consistent with the ISG guidelines and NEI 12-02.

In its letter dated July 24, 2013, the licensee stated, in part, that:

Device testing requirement analysis will be performed as part of the process and procedure development following the design phase. The current plan for the design of the SF PI system based on the current Exelon Nuclear program schedule for TMI-1 is to begin the design phase in October 2013 with design completion and 100% acceptance of the design in May 2014. Following the issue of the design, procedures will start being developed with a projected September 2015 completion date. The requested information will be developed early in the process and will be provided in the February 2015, 6-month Integrated Plan update.

The NRC staff notes that the information regarding SFP level instrumentation testing requirements is not currently available for review and that in its letter dated August 28, 2013, the licensee identified the status of this activity as "Not Started." The licensee indicated that the information will be provided to the staff during the February 2015, 6-month OIP update. The staff has identified this request as:

RAI #12 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 functional checks will be performed, and the frequency at which they will be conducted. Describe how calibration tests will be performed, and the frequency at which they will be conducted. Provide a discussion as to how these surveillances will be incorporated into the plant surveillance program.

d) A description of what preventive maintenance tasks are required to be performed during normal operation, and the planned maximum surveillance interval that is necessary to ensure that the channels are fully conditioned to accurately and reliably perform their functions when needed.

(This information was previously requested as RAI-8 in the NRC letter dated June 26, 2013) 3.11 Design Features: Display of Order EA-12-051 states, in part, that:

Trained personnel shall be able to monitor the spent fuel pool water level from the control room, alternate shutdown panel, or other appropriate and accessible location. The display shall provide on-demand or continuous indication of spent fuel pool water level.

NEI 12-02 states, in part, that:

The intent of this guidance is to ensure that information on SFP level is reasonably available to the plant staff and decision makers. Ideally there will be an indication from at least one channel of instrumentation in the control room.

While it is generally recognized (as demonstrated by the events at Fukushima Daiichi) that SFP level will not change rapidly during a loss of spent fuel pool cooling scenario more rapid SFP drain down cannot be entirely discounted.

Therefore, the fact that plant personnel are able to determine the SFP level will satisfy this requirement, provided the personnel are available and trained in the use of the SFP level instrumentation (see Section 4.1) and that they can accomplish the task when required without unreasonable delay.

SFP level indication from the installed channel shall be displayed in the control room, at the alternate shutdown panel, or another appropriate and accessible location (reference NEI 12-06). An appropriate and accessible location shall have the following characteristics:

• occupied or promptly accessible to the appropriate plant staff giving appropriate consideration to various drain down scenarios,

• outside of the area surrounding the SFP floor, e.g., an appropriate distance from the radiological sources resulting from an event impacting the SFP,

• inside a structure providing protection against adverse weather, and

• outside of any very high radiation areas or LOCKED HIGH RAD AREA during normal operation.

If multiple display locations beyond the required "appropriate and accessible location" are desired, then the instrument channel shall be designed with the capability to drive the multiple display locations without impacting the primary "appropriate and accessible" display.

In its OIP, the licensee stated that the primary and backup instrument displays would be located at the control room, alternate shutdown panel, or other appropriate and accessible location. Also, the licensee stated that the specific location will be determined during detailed design.

In its letter dated July 24, 2013, the licensee stated, in part, that:

Device channel display location will be finalized during the detailed design process. The current plan for the design of the SF PI system based on the current Exelon Nuclear program schedule for TMI-1 is to begin the design phase in October 2013 with design completion and 100% acceptance of the design in May 2014. The requested information will be provided in the August 2014, 6-month Integrated Plan update.

The NRC staff notes that the information regarding the SFP level instrumentation channel displays location is not currently available for review and that in its letter dated August 28, 2013, the licensee identified the status of this activity as "Not Started." The licensee indicated that the information will be provided to the staff during the August 2014, 6-month OIP update. The staff has identified this request as:

RAI #13 Please provide the following:

a) The specific location for each of the primary and backup instrument channel displays.

b) For any SFP level instrumentation displays located outside the main control room, please describe the evaluation used to validate that the display location can be accessed without unreasonable delay following a BOB event. Include the time available for personnel to access the display as credited in the evaluation, as well as the actual time (e.g., based on walk-throughs) that it will take for personnel to access the display. Additionally, please include a description of the radiological and environmental conditions on the paths personnel might take. Describe whether the display location remains habitable for radiological, heat and humidity, and other environmental conditions following a BOB event. Describe whether personnel are continuously stationed at the display or monitor the display periodically.

3.12 Programmatic Controls: Training of Order EA-12-051 states, in part, that:

Personnel shall be trained in the use and the provision of alternate power to the primary and backup instrument channels.

NEI 12-02 states, in part, that:

The personnel performing functions associated with these SFP level instrumentation channels shall be trained to perform the job specific functions necessary for their assigned tasks (maintenance, calibration, surveillance, etc.).

SFP instrumentation should be installed via the normal modification processes.

In some cases, utilities may choose to utilize portable instrumentation as a portion of their SFP instrumentation response. In either case utilities should use the Systematic Approach to Training (SAT) to identify the population to be trained. The SAT process should also determine both the initial and continuing elements of the required training.

In its OIP, the licensee stated, in part, that:

Personnel performing functions associated with these SFP level instrumentation channels will be trained to perform the job specific functions (maintenance, calibration, surveillance, etc.). This training will be consistent with equipment vendor guidelines, instructions and recommendations. The Systematic Approach to Training (SAT) will be used to identify the population to be trained and to determine the initial and continuing elements of the required training. Training will be completed prior to placing the instrumentation in service.

The licensee's proposed plan to train personnel in the use and the provision of alternate power to the primary and backup instrument channels, including the approach to identify the population to be trained appears to be consistent with NEI 12-02, as endorsed by the ISG.

3.13 Programmatic Controls: Procedures of Order EA-12-051 states, in part, that:

Procedures shall be established and maintained for the testing, calibration, and use of the primary and backup spent fuel pool instrument channels.

NEI 12-02 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.

In its OIP, the licensee stated that procedures would be developed using guidelines and vendor instructions to address the maintenance, operation and abnormal response issues associated with the primary and backup channels of SFP instrumentation.

In its letter dated July 24, 2013, the licensee stated, in part, that:

Device program features analysis will be performed as part of the detailed design process following the design phase. The current plan for the design of the SF PI system based on the current Exelon Nuclear program schedule for TMI-1 is to begin the design phase in October 2013 with design completion and 100%

acceptance of the design in May 2014. Following the issue of the design, procedures will start being developed with a projected September 2015 completion date. The requested information will be developed early in the process and will be provided in the February 2015, 6-month Integrated Plan update The NRC staff notes that the information regarding SFP level instrumentation program features is not currently available for review and that in its letter dated August 28, 2013, the licensee identified the status of this activity as "Not Started." The licensee indicated that the information will be provided to the staff during the February 2015, 6-month OIP update. The staff has identified this request as:

RAI #14 Please provide a list of the procedures addressing operation (both normal and abnormal response), calibration, test, maintenance, and inspection procedures that will be developed for use of the SFP instrumentation. The licensee is requested to include a brief description of the specific technical objectives to be achieved within each procedure.

3.14 Programmatic Controls: Testing and Calibration of Order EA-12-051 states, in part, that:

Processes shall 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.

NEI 12-02 states, in part, that:

Processes shall be established and maintained for scheduling and implementing necessary testing and calibration of the primary and backup SFP level instrument channels to maintain the instrument channels at the design accuracy. The testing and calibration of the instrumentation shall be consistent with vendor recommendations or other documented basis.

In its OIP, the licensee stated, in part, that:

The testing and calibration of the instrumentation will be consistent with vendor recommendations or other documented basis. Calibration will be specific to the mounted instruments and the displays. A Maintenance Procedure (e.g., 1430 series) will be written to direct calibration and repair of the instruments.

Database IISCP (Improved instrument Setpoint Control Program) will be used to control the calibration and setpoint parameters. The PIMS PM system will be used to direct the calibration frequency of the instruments.

In its letter dated July 24, 2013, the licensee stated, in part, that:

Device testing and calibration requirements analysis will be performed as part of the detailed design process following the design phase. The current plan for the design of the SF PI system based on the current Exelon Nuclear program schedule for TMI-1 is to begin the design phase in October 2013 with design completion and 100% acceptance of the design in May 2014. Following the issue of the design, procedures will start being developed with a projected September 2015 completion date. The requested information will be developed early in the process and will be provided in the February 2015, 6-month Integrated Plan update.

The NRC staff notes that the information regarding testing and calibration program requirements for the SFP level instrumentation is not currently available for review and that in its letter dated August 28, 2013, the licensee identified the status of this activity as "Not Started." The licensee indicated that the information will be provided to the staff during the February 2015, 6-month OIP update. The staff has identified this request as:

RAI #15 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. Please 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 NEI12-02, Section 4.3 regarding compensatory actions for one or both non-functioning channels will be addressed.

c) A description of what compensatory actions are planned in the event that one of the instrument channels cannot be restored to functional status within 90 days.

(This information was previously requested as RAI-11 in the NRC letter dated June 26, 2013) 3.15 Instrument Reliability NEI 12-02 states, in part, that:

A spent fuel pool level instrument channel is considered reliable when the instrument channel satisfies the design elements listed in Section 3 [Instrument Design Features] of this guidance and the plant operator has fully implemented the programmatic features listed in Section 4 [Program Features].

In its OIP, the licensee stated that the reliability of the primary and backup channels is to be assured through conformance with the guidance in NEI 12-02 and the NRC staff's ISG, and that such reliability will be demonstrated through testing, analysis, qualification, and operating experience.

Upon acceptable resolution of the RAis noted above, the NRC staff will be able to make a conclusion regarding the reliability of the SFP instrumentation.

4.0 CONCLUSION

The NRC staff is unable to complete its evaluation regarding the acceptability of the licensee's plans for implementing the requirements of Order EA-12-051 due to the need for additional information as described above. The staff will issue an evaluation with its conclusion after the licensee has provided the requested information.

M13308C188 *via memo **via email OFFICE NRR/DORL/LPL 1-2/PM NRR/DORL/LPL 1-2/LA NRR/DSS/SBPB/BC NAME JHughey A Baxter** GCasto*

DATE 11/13/2013 11/7/2013 10/07/2013 OFFICE NRR/DE/EICB/BC NRR/DORLILPL 1-2/BC NRR/DSS/SBPB/BC NAME JThorp DRahn/for

• VRodriguez (Acting) JHughey DATE 10/07/2013 11/12/2013 11/13/2013