ML13275A187

Interim Staff Evaluation and Request for Additional Information Regarding the Overall Integrated Plan for Implementation of Order EA-12-051

ML13275A187
Person / Time
Site:	Monticello
Issue date:	10/28/2013
From:	Beltz T Plant Licensing Branch III
To:	Fili K Northern States Power Co
Beltz T
References
EA-12-051, TAC MF0924
Download: ML13275A187 (27)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Mrs. Karen D. Fili Site Vice President Monticello Nuclear Generating Plant October 28, 2013 Northern States Power Company - Minnesota 2807 West County Road 75 Monticello, MN 55362-9637

SUBJECT:

MONTICELLO NUCLEAR GENERATING PLANT-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 (TAG NO. MF0924)

Dear Mrs. Fili:

On March 12,2012, the U.S. Nuclear Regulatory Commission (NRC) issued Order EA-12-051, "Order Modifying Licenses with Regard to Reliable Spent Fuef 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. ML13060A447), Northern States Power Company-Minnesota, doing business as Xcel Energy, Inc. (the licensee), provided the Overall Integrated Plan (OIP) for the Monticello Nuclear Generating Plant describing how it will achieve compliance with Attachment 2 of Order EA-12-051 by spring 2015. By e-mail dated June 7, 2013 (ADAMS Accession No. ML13176A331 ), the NRC staff sent a request for additional information (RAI) to the licensee: The licensee provided supplemental information by letters dated July 12,2013 (ADAMS Accession No. ML13193A324) and August 28,2013 (ADAMS Accession No. ML13241A197).

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, responses to which the NRC staff needs to complete its review. The licensee should provide the information requested in the 6-month

.J K. D.Fili *status updates, as the information becomes available. However, the staff requests that all information be provided by September 30, 2014, 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 301-415-3049 or via e-mail at Terrv.Beltz@nrc.gov.

. Docket Nos. 50-263

Enclosure:

Interim Staff Evaluation and Request for Additional Information cc w/encl: Distribution via Listserv Sincerely, Terry. Beltz, Senior Project Manager Plant Licensing Branch 111-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

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 NORTHERN STATES POWER COMPANY-MINNESOTA MONTICELLO NUCLEAR GENERATING PLANT DOCKET NO. 50-263 (TAC NO. MF0924) 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 rec9very 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 (1 0 CFR) Part 50, "Domestic Licensing of Production and Utilization Facilities," to submit to the NRC an*overalllntegrated Plan (OIP) by February 28, 2013.

By letter dated February 28, 2013 (ADAMS Accession No. ML13060A447), Northern States Power Company-Minnesota, doing business as Xcel Energy, Inc. (the licensee), provided the OIP for the Monticello Nuclear Generating Plant describing how it will achieve compliance with of Order EA-12-051 by spring 2015. By e-mail dated June 7, 2013 (ADAMS Accession No. ML13176A331 ), the NRC staff sent a request for additional information (RAI} to the licensee. The licensee provided supplemental information by letters dated July 12, 2013 (ADAMS Accession No. ML13193A324) and August 28, 2013 (ADAMS Accession No. ML13241A197).

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 01 P or December 31, Enclosure 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. of Order EA-12-051 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 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.

~ 3 -

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, alter~ate 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 document (the ISG),

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 24, 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 Monticello Nuclear Generating Plant (MNGP) has a single SFP.

The licensee's OIP, was submitted on February 28, 2013. The OIP states that installation of the SFP level instrumentation at MNGP is scheduled for completion prior to startup from Refueling Outage in the spring of 2015.

The NRC staff has reviewed the licensee's schedule for implementation of SFP level instrumentation provided in its OIP. 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 Level1 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.

In its OIP, the licensee stated, in part, that Level 1 is the level that is adequate to support operation of the normal fuel pool cooling system. Currently, the level in the fuel pool is maintained at a constant level due to overflow weirs that spill into skimmer surge tanks. This configuration permits the total water volume to change within the skimmer surge tanks but it does not impact the spent fuel pool water level. The minimum level, without weirs, where the skimmer surge tank and the spent fuel pool become decoupled is 37 feet and 3 inches from the bottom of the spent fuel pool. This level will be used for Level 1. Allowance for instrumentation accuracy will be applied to this setpoint.

In its letter dated July 12,. 2013 the licensee stated, in part, that The water level.in the skimmer surge tanks, not the water level in the SFP, provides the required net positive suction head to the fuel pool cooling and cleanup pumps. The fuel pool cooling and cleanup pumps are tripped on low level in the skimmer surge tarik.

The minimum SFP level that assures water is delivered to the fuel pool cooling and cleanup pumps is a SFP level that is above the height of the weir. Therefore, the SFP "level that is adequate to support operation of the normal fuel pool cooling system" is slightly above the height of the weir. In the MNGP OIP, Level 1 was established based on the minimum SFP level, without the weirs attached, where the skimmer surge tank and the SFP become decoupled. Therefore, Level 1 for Monticello appropriately reflects the-intent of the first of the two bullets in NEI 12-02, Section 2.3.1.

In its letter dated July 12, 2013, the licensee provided a sketch showing the elevations identified as Levels 1, 2 and 3. This sketch shows Level 1 at an elevation of 37 (ft.) 3 (in.), which is aligned with the lowest height of the weir.

The NRC staff notes that Level1 is adequate for normal SFP cooling system operation; it is also sufficient for NPSH an? represents the higher of the two points described above.

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 ( +1-1 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 apprqpriate 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, in part, that Based on the guidance in Section 2.3 of NEI 12-02, Level 2 is 10 feet above the top of the spent fuel rack, which corresponds to 24 feet and 9 inches from the bottom of the MNGP spent fuel storage pool.

The NRC notes that the licensee designated Level 2 using the first of the two options described in NEI 12-02 for Level 2.

In its OIP, the license stated that, "An evaluation of other hardware stored in the SFP will be conducted as part of the design process to ensure other hardware will not adversely interact with the fixed instrument locations." The NRC staff has concerns with the lack of information regarding the effect of varied dose rates from hardware stored in the SFP on the licensee's evaluation to identify Level 2.

RAI #1 Given the potential for varied dose rates from hardware stored in the SFP, please provide a description of how the elevation identified 'as Level 2 might be affected.

NEI 12-02 states, in part, that Level 3 corresponds nominally (i.e., +1-1 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, in part, that Level 3 corresponds nominally to the highest point of the fuel rack in the spent fuel pool. Level 3 will be 14 feet and 9 inches from the bottom of the spent fuel storage pool.

In its letter dated July 18, 2013, the licensee provided a sketch showing the approximate location of the level sensor and the elevations identified as Levels 1, 2 and 3. This sketch shows Level 3 at an elevation of 14 ft. 9 in., which is approximately 10 ft. above the top of the fuel rack.

The NRC notes that this elevation is the highest point of any spent fuel storage rack seated in the SFP.

The licensee's proposed plan, with respect to identification of Levels 1 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, f_ixed primary instrument channel and a backup instrument channel. The backup instrument channel may be fixed or portable. Portaqle 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 that the primary and backup instrument channel.level sensing components would be located and permanently mounted in the SFP. The primary and backup instrument channel would be identical to and independent from each other, and would be based on a guided wave radar system. The licensee also stated that the device will be a level monitoring system capable of measuring the range of levels identified by the licensee.

In its letter dated July 12, 2013, the licensee provided a sketch depicting the elevation view of the Monticello Nuclear Generating Plant SFP showing the proposed Level 1, 2, and 3 values, the top of the fuel racks and the bottom of the SFP, and the level sensor range. The NRC staff reviewed this sketch and notes that the proposed sensor range is approximately 22ft. 6 in.

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 the MNGP SFP appears to be consistent with NEI 12-02, as endorsed by the ISG.

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 3.2.1 Probes The probe for the primary channel level transmitter will be located near or in a corner of the spent fuel pool to utilize the inherent shielding from missiles. The final length, location, and mounting of the probe will be determined during the design process.

The probe for the backup channel level transmitter will be located across.the spent fuel pool from the probe of the primary level transmitter. The backup channel probe will be located in or near a different corner of the pool. The final length, location and mounting of the backup channel probe will be determined during the design process.

The primary and backup level transmitter probes will be located in separate corners, which will allow separation between the probes and will also provide protection against a single missile damaging both the primary and the backup spent fuel pool probes.

3.2.2 Mounting The cable routing for the primary and backup instrument channels will be diverse and protected from external events, in accordance with the requirements of NRC JLD-ISG-2012-03 and NEI 12-02. No cables will be routed outside structures.

The conduit and cable routing will be determined during the design process.

In its letter dated July 12, 2013, the licensee stated, in part, that The planned locations for the primary and back-up level sensors, the mounting brackets and the proposed routing of the cables have not been determined. The final component locations will be available upon completion of the final design.

NSPM's current plan is to begin the design phase for the SFPI system by January 2014, with design completion expected in July 2014. The requested information will be provided with the August 2014, six-month status report.

In its letter dated August 28, 2013, the licensee stated that the planned location for the primary and backup level sensor, the mounting brackets and the proposed routing of the cables have not been determined. The NRC staff notes that the licensee identified the status of this item "Not Started" and that further information will be provided to the staff in the August 2014, six-month status report. The staff has identified this request as:

RAI#2 I

Please provide a clearly labeled sketch or marked-up plant drawing of the plan view of the SFP area, depicting the SFP inside dimensions, the planned locations/placement of the primary and back-up SFP level sensor, and the proposed routing of the cables that will extend from these sensors toward the location of the read-out/display device.

(This information was previously requested as RAI-2 in the NRC e-mail dated June 7, 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, in part, that, Both the primary and backup system mounting will be installed as Seismic Category I to meet the NRC JLD-ISG-2012-03 and NEI 12-02 guidance requirements. An evaluation of other hardware stored in the spent fuel pool will be conducted as part of the design process to ensure other hardware will not adversely interact with the fixed instrument locations.

In its letter dated July 12, 2013, the licensee stated, in part, that NSPM's current plan is to begin the design phase for the SFPI system by January 2014, with design completion expected in July 2014. The requested information will be provided with the August 2014, six-month status report.

In its letter dated August 28, 2013, the licensee indicated that the information regarding mounting of the SFP instrumentation is not available. The NRC staff notes that the licensee identified the status of this item "Not Started" and that further information will* be provided to the staff in the August 2014, six-month status report. The staff has identified these requests as:

RAI#3 Please provide the following:

• a) The design criteria that will be used to estimate the total loading on the mounting device(s), including static weight loads and dynamic loads.

Describe the methodology that will be used to estimate the total loading, inclusive of design basis maximum seismic loads and the hydrodynamic loads that could result from pool sloshing or other effects that could accompany such seismic forces.

b) A description of the manner in which the level sensor (and stilling well, if appropriate) will be attached to the refueling floor and/or other support structures for each planned point of attachment of the probe assembly.

Indicate in a schematic the portions of the level sensor that will serve as points.

of attachment for mechanical/mounting or electrical connections.

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

d) Address how other hardware stored in the SFP will not create adverse interaction with the fixed instrument location(s);

. (This information was previously requested as RAI-3 in NRC e-mail dated June 7, 20.13)

In addition, the staff plans to verify the results of the licensee's seismic testing and analysis when it is completed based on the licensee's response to the following RAI.

RAI#4 For RAI 3(a) above, please provide 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 #5 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 spentfuel 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 below: (3.6.1) Augmented Quality Process, (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 primary and backup instrument channels will be qualified through the use of an augmented quality assurance process that meets the NRC JLD-ISG-

• 2012-03 and NEI 12-02 guidance requirements.

The licensee's proposed augmented quality assurance process appears to be consistent with NEI 12-02, as endorsed by the ISG.

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, in part, that 3.4.1 Conditions Both the primary and.the backup instrument channels will be capable of performing their function and maintaining the required accuracy under conditions described by NRC JLD-ISG-2012-03 and Section 3.4 of NEI 12-02. Per this guidance, the sensor and cables for both of the channels will be reliable at the temperature, humidity and radiation levels consistent with conditions in the vicinity of the spent fuel pool and the area of use for normal operation, event and post-event conditions. The sensors and cables located in the vicinity of the SFP will be qualified to withstand these conditions for an extended period consistent with strategies developed in response to NRC Order EA-12-049 and NEI12-06.

3.4.2 Shock and Vibration The primary and backup instrument channel components required after an event will be rated for anticipated shock and vibration per the recommendations of NRC

' JLD~ISG-2012-03 and NEI 12-02, Section 3.4.

3.4.3 Seismic The applicable primary and backup instrument channel components will be qualified for reliable operation following a seismic event. The methods used to qualify components will be consistent with the guidance of NEI 12-02 and the exceptions and clarifications to NEI 12-02 provided by the NRC Staff in NRC JLD-ISG-2012-03. Mounting of components for reliable operation following a seismic event is addressed in Section 3.3 of this Enclosure.

In its letter dated July 12, 2013, the licensee stated, in part, that NSPM's current plan is to begin the design phase for the SFPI system by January 2014, with design completion expected in July 2014. The requested information will be provided with the August 2014, six-month status report.

In its letter dated August 28, 2013, the licensee indicated that the information regarding qualification of the SFP instrumentation is not available. The NRC staff notes that the licensee identified the status of this item "Not Started" and that further information will be provided to the staff in the August 2014, six-month status report. The staff has identified these requests as:

RAI#6 Please provide the following:

a) A description of the specific method or combination of methods you intend to apply to demonstrate the reliability of the permanently installed equipment under beyond-design-basis ambient temperature, humidity, shock, vibration, and radiation conditions.

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

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

(This information was previously requested as RAI-4 in the NRC e-mail dated June 7, 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 compl~ted based on the licensee's response to the following RAI.

RAI#7 For RAI #6 above, please provide the results for the selected methods, tests and analyses used to demonstrate the qualification and reliability of the installed equipment in accordance with the Order requirements.

~ 14-3.6.3 Qualification Evaluation Summary Upon acceptable resolution of the RAisin Section 3.6, 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.

N El 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, in part, that

. The primary chann.el will be independent of the backup channel. Both channels will have their own probes located in separate corners of the spent fuel pool with separate cable routes and separate electronics. Where routed in conduit and cable trays, the primary and backup channel cabling will be routed in separate

• conduit or cable trays to achieve independence.

In its letter dated July 12, 2013, the licensee stated, in part, that NSPM's current plan is to begin the design phase for the SFPI system by January 2014, with design completion expected in July 2014. The requested information will be provided with the August 2014; six-month status report.

In its letter dated August 28, 2013, the licensee indicated that the information regarding independence of the SFP instrumentation is not available. The NRC staff notes.that the licensee identified the status of this item "Not Started" and that further information will be provided to the staff in the August 2014, six-month status report. The staff has identified this request as:

RAI #8 Please p~ovide 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 thro.ugh 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 NRC e-mail dated June 7, 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 *acc;:essible 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, The instrument channels will each have an independent backup battery power supply that will be capable of supporting the instrument until repowered as specified by the mitigating strategies of NRC Order EA-12-049 and NE112-06.

Any onsite generators used as an alternate power source and replaceable batteries used for instrument channel function will have sufficient capacity to maintain level indication function until offsite resource availability is reasonably assured.Any portable power supplies used will be stored consistent with the requirements of NRC Order EA-12-049 and NEI12-06. The design process will.

determine the normal power source, battery power supply, and any additional power sources required for the instrument channels. Both the primary and the backup instrument channels will maintain their design accuracy without recalibration following a power interruption or change in the power source as required by NRC Order EA-12-051.

In its letter dated July 12, 2013, the licensee stated, in part, that NSPM's current plan is to begin the design phase for the SFPI system by January 2014, with design completion expected in July 2014. The requested information will be provided with the August 2014, six-month status report.

In its letter dated August 28, 2013, the licensee indicated that the information regarding power supply for the SFP instrumentation is not available. The NRC staff notes that the licensee identified the status of this item "Not Started" and that further information will be provided to the staff in the August 2014, six-month status report. The staff has identified this request as:

RAI#9 Please provide the following:

r 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 NRC e-mail dated June 7, 2013) 3.9 Design Features: Accuracy

.Attachment 2 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 consid~r 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 primary and backup instrument channels will maintain their design accuracy without requiring recalibration following a power interruption or change in the power source as required by NRC Order EA-12-051. The total loop accuracy of the primary system and the backup system will be determined for the entire span (Level 1 through 3) during the design process.

In its ~uly 12, 2013 letter, the licensee stated, in part, that Setpoints will be determined following Monticello procedure ESM-03.02, "Design Requirements, Practices & Topics (Instrumentation & Controls)." This procedure allows for several options for setpoint determination. Determination of setpoints using this procedure is part of the NSPM design process. NSPM's current plan is to begin the design phase for the SFPI system by January 2014, with design completion expected in July 2014. The requested information will be provided with the August 2014, six-month status report.

In its letter dated August 28, 2013, the licensee indicated that setpoints will be determined following a licensee procedure and that determination of setpoints using this procedure is part of the NSPM design process. The NRC staff notes that the licensee identified the status of this item "Not Started" and that further information will be provided to the staff in the August 2014, six-month status report. The staff has identified this request as:

RAI #10 Please provide the following:

a) An estimate of the expected instrument channel accuracy performance under both (a)-normal SFP level conditions (approximately Level1 or higher) and (b) at the beyond design-basis conditions (i.e., radiation, temperature, humidity, post-seismic and post-shock conditions) that would be present if the SFP level were at the Level2 and Level3 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 NRC e-mail dated June 7, 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, in part, that The instrument channel design will provide for routine testing and calibration. The

. primary and backup instrumentation channels will be capable of in-situ testing and calibration.

In its letter dated July 12, 2013, the licensee stated, in part, that NSPM's current plan is to begin the design phase for the SFPI system by January 2014, with design completion expected in July 2014. The requested information will be provided with the August 2014, six-month status report.

In its letter dated August 28, 2013, the licensee indicated that the information regarding the design of the SFP instrumentation to provide for routine testing and calibration is not available.

The NRC staff notes that the licensee identified the status of this item "Not Started" and that further information will be provided to the staff in the August 2014, six-month status report. The staff has identified this request as:

RAI #11 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 NRC e-mail dated June 7, 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:

o 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, in part, that The primary display will be located in the coritrol room and will provide the operators an on-demand or continuous display of the spent fuel pool level. The backup display will be located in an area which meets the four characteristics defined in NEI 12-02, Section 3.9. The location for both of the electronics control cabinets will be determined during the design process.

In its letter dated July 12, 2013, the licensee stated, in part, that NSPM's current plan is to begin the design phase for the SFPI system by January 2014, with design completion expected in July 2014. The requested information will be provided with the August 2014, six-month status report.

In its letter dated August 28, 2013, the licensee indicated that the information regarding the location of the SFP instrumentatfon displays is not available. The NRC staff notes that the licensee identified the status of this item "Not Started" and that further information will be provided to the staff in the August 2014, six-month status report. The staff has ide(ltified this request as:

RAI #12 Please provide the following:

(

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

b) 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 will be trained in the use and the provision of alternate power to the primary and backup instrument channels, as determined by plant processes and procedures. NSPM's Systematic Approach to Training (SAT) will be used to identify the population to be trained, as well,as the initial and cqntinuing elements of the required training.

The licensee's proposed plan, with respect to the training personnel in the use and the provision "

of alternate power to the primary and backup instrument channels, including the approach to identifying 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, in part, that Procedures will be developed for both the primary and backup instrument channels consistent with the requirements of NRC JLD-ISG-2012-03 and NEI 12-02, Section 4.2. This will include procedures for the maintenance, operation, testing, calibration and normal/abnormal response of the primary and backup instrument channels.

In its letter dated July 12, 2013, the licensee stated, in part, that NSPM's current plan is to begin the design phase for the SFPI system by January 2014, with design completion expected in July 2014. The requested information will be provided with the February 2015, six-month status report.

In its letter dated August 28, 2013, the licensee indicated that the information regarding the SFP instrumentation procedures to be established and maintained for the testing, calibration, and use of the primary and backup instrument channels is not available. The NRC staff notes that the licensee identified the status of this item "Not Started" and that further information will be provided to the staff in the August 2014, six-month status report. The staff has identified this request as:

RAI #13 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 spent SFP instrumentation. Please provide 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 t~sting and calibration of the instrumentation shall be consistent with vendor recommendations or other documented basis.

In its OIP, the licensee stated, in part, that Testing and calibration of theprimary and backup instrument channels will be established and implemented by existing MNGP processes, and will be scheduled in intervals such that the design accuracy of the instrument channels is maintained. Surveillance or testing intervals will be established per the recommendations of NEI 12-02, Section 4.3. Allowed out of service time as identified in NEI 12-02 will be incorporated consistent with the programmatic process used for compliance with NRC Order EA-12-49.

In its letter dated July 12, 2013, the licensee stated, in part, that NSPM's current plan is to begin the design phase for the SFPI system by January 2014, with design completion expected in July 2014. The requested information will be provided with the August 2014, six-month status report.

In its letter dated August 28, 2013, the licensee indicated that the information regarding testing and calibration of the SFP instrumentation is not available. The NRC staff notes that the licensee identified the status of this item "Not Started" and that further information will be provided to the staff in the August 2014, six-month status report. The staff has identified this request as:

RAI #14 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~he guidance in NEI12-02 se.ction 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 NRC e-mail dated June 7, 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 instrument channels will be assured by conformance with the guidelines of NRC JLD-ISG-2012-03 and NEI 12-02.

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.

ML13275A187 OFFICE N RR/DORULPL3-1 /PM NAME TBeltz DATE 10/04/13 OFFICE NRR/DSS/SBPB/BC**

NAME GCasto DATE 10/01/13 Sincerely, IRA/

Terry A. Beltz, Senior Project Manager Plant Licensing Branch 111-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation RidsRgn3MaiiCenter Resource CRoque-Cruz, NRR DRahn, NRR GCasto, NRR JThorp, NRR MMitchell, NRR RKuntz, NRR BPurnell, NRR

• via e-mail

• • via memo NRR/DORULPL3-1/LA NRR/DE/EICB/BC*

MHenderson JThorp (DRahn for) 10/22/13 09/30/13 NRR/DORULPL3-1/BC NRR/DORULPL3-1/PM RCarlson TBeltz 10/24/13 10/28/13