RS-15-030, Fourth Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051)

Fourth Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051)

ML15058A252
Person / Time
Site:	Limerick
Issue date:	02/27/2015
From:	Jim Barstow Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
EA-12-051, RS-15-030
Download: ML15058A252 (18)

Text

Order No. EA-12-051 RS-15-030 February 27, 2015 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Limerick Generating Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-39 and NPF-85 NRC Docket Nos. 50-352 and 50-353

Subject:

Fourth Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051)

References:

1. NRC Order Number EA-12-051, "Issuance of Order to Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation," dated March 12, 2012

2. NRC Interim Staff Guidance JLD-ISG-2012-03, "Compliance with Order EA-12-051, Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation,"

Revision 0, dated August 29, 2012

3. NEI 12-02, Industry Guidance for Compliance with NRC Order EA-12-051, "To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation," Revision 1, dated August 2012

4. Exelon Generation Company, LLC's Initial Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051 ), dated October 25, 2012

5. Exelon Generation Company, LLC Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051), dated February 28, 2013 (RS-13-032)

6. Exelon Generation Company, LLC First Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051), dated August 28, 2013 (RS-13-122)

7. Exelon Generation Company, LLC Second Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051 ), dated February 28, 2014 (RS 022)

8. Exelon Generation Company, LLC Third Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051), dated August 28, 2014 (RS-14-200)

U.S. Nuclear Regulatory Commission Integrated Plan Report to EA-12-051 February 27, 2015 Page 2

9. NRC letter to Exelon Generation Company, LLC, Limerick Generating Station, Units 1 and 2 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 Nos. MF0854 and MF0855), dated October 23, 2013 On March 12, 2012, the Nuclear Regulatory Commission ("NRC or "Commission") issued an order (Reference 1) to Exelon Generation Company, LLC (EGC). Reference 1 was immediately effective and directs EGC to install reliable spent fuel pool level instrumentation. Specific requirements are outlined in Attachment 2 of Reference 1.

Reference 1 required submission of an initial status report 60 days following issuance of the final interim staff guidance (Reference 2) and an overall integrated plan pursuant to Section IV, Condition C. Reference 2 endorses industry guidance document NEI 12-02, Revision 1 (Reference 3) with clarifications and exceptions identified in Reference 2. Reference 4 provided the EGC initial status report regarding reliable spent fuel pool instrumentation. Reference 5 provided the Limerick Generating Station, Units 1 and 2 overall integrated plan.

Reference 1 requires submission of a status report at six-month intervals following submittal of the overall integrated plan. Reference 3 provides direction regarding the content of the status reports. References 6, 7, and 8 provided the first, second, and third six-month status reports, respectively, pursuant to Section IV, Condition C.2, of Reference 1 for Limerick Generating Station. The purpose of this letter is to provide the fourth six-month status report pursuant to Section IV, Condition C.2, of Reference 1, that delineates progress made in implementing the requirements of Reference 1. The enclosed report provides an update of milestone accomplishments since the last status report, including any changes to the compliance method, schedule, or need for relief and the basis, if any. The enclosed report also addresses the NRC Interim Staff Evaluation Request for Additional Information Items contained in Reference 9.

This letter contains no new regulatory commitments. If you have any questions regarding this report, please contact David P. Helker at 610-765-5525.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 27th day of February 2015.

Respectfully submitted, James Barstow Director - Licensing & Regulatory Affairs Exelon Generation Company, LLC

Enclosure:

1. Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for the Implementation of Order EA-12-051, Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation

U.S. Nuclear Regulatory Commission Integrated Plan Report to EA-12-051 February 27, 2015 Page 3 cc: Director, Office of Nuclear Reactor Regulation NRC Regional Administrator Region I NRC Senior Resident Inspector - Limerick Generating Station, Units 1 and 2 NRC Project Manager, NRR - Limerick Generating Station, Units 1 and 2 Ms. Jessica A. Kratchman, NRR/JLD/PMB, NRC Mr. Stephen R. Monarque, NRR/JLD/JPMB, NRC Mr. Robert L. Dennig, NRR/DSS/SCVB, NRC Mr. Richard B. Ennis, NRR/DORULPL3-2, NRC Mr. John D. Hughey, NRR/JLD/JOMB, NRC Director, Bureau of Radiation Protection - Pennsylvania Department of Environmental Resources R. R. Janati, Chief, Division of Nuclear Safety, Pennsylvania Department of Environmental Protection, Bureau of Radiation Protection

Enclosure Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for the Implementation of Order EA-12-051, Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (14 pages)

Limerick Generating Station. Units I and 2 Fourth Six-Month Status Report for the Implementation of SFPLI February 27. 20 I 5 Fourth Six-Month Status Report for the Implementation of Order EA-12-051, Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation I Introduction Limerick Generating Station, Units I and 2. developed an Overall Integrated Plan (Reference 1 in Section 8), documenting the requirements to install Reliable Spent Fuel Pool Level Instrumentation (SFPLI), in response to NRC Order EA-12-051 (Reference This enclosure provides an update of milestone accomplishments since submittal of the third six month status report including any changes to the compliance method, schedule, or need for relief I relaxation and the basis. if any.

2 Milestone Accomplishments The following milestones have been completed since the submittal of the Third Six Month Status Report, (Reference 8) and are current as of January 31, 2015.

• SFPLI Modification Package is complete and issued.

3 Milestone Schedule Status The following provides an update to the milestone schedule to support the Overall Integrated Plan. This section provides the activity status of each item, and the expected completion date noting any change.

The dates are planning dates subject to change as design and implementation details are developed.

The revised milestone target completion dates do not impact the order implementation date.

Revised Target Target Completion Milestone Activity Status Completion Date Date Submit 60 Day Status Report October 25. 2012 Complete Submit Overall Integrated Plan February 28, 2013 Complete Submit Responses to RAis July 18, 2013 Complete Submit 6 Month Updates:

Update 1 August 28, 2013 Complete Update 2 February 28, 2014 Complete Update 3 August 28. 2014 Complete Provide Final Safety Evaluation September 30, 2014 Complete (SE) Information Complete with Update 4 February 28, 2015 this submittal Page I of 14

Limerick Generating Station. Units 1 and 2 Fourth Six-Month Status Report for the Implementation of SFPLI b

Fe.ruary '1015.

LI."-

Revised Target Target Completion Milestone Activity Status Completion Date Date Modifications:

Conceptual Design 3()2012 Complete Issue Exelon Fleet contract to 1()2015 Complete procure SFPI Equipment Begin Detailed Engineering Design 3()2013 Complete Complete and Issue SFPI 3()2014 Complete Modification Package Begin Installation IQ2015 Complete Complete SFPI Installation and Put 1()2015 Started Into Service 4 Changes to Compliance Method There are no changes to the compliance method as documented in the Overall Integrated Plan (Reference I).

5 Need for Relief/Relaxation and Basis for the Relief/Relaxation Limerick Generating Station, Units 1 and 2 expects to comply with the order implementation date and no relief/relaxation is required at this time.

6 Open Items from Overall Integrated Plan and Interim Staff Evaluation The following tables provide a summary of the open items documented in the Overall Integrated Plan (OIP) or the Intetim Staff Evaluation (ISE) and the status of each item.

Overall Integrated Plan Open Items OIP# Description Status 1 Open Item: Complete Continuous level indication will be (Addressed in Reference 6) provided by a guided wave radar system, submersible pressure transducer, or other appropriate level sensing technology that will be determined during the detailed engineering phase of the project.

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Limerick Generating Station. Units I and 2 Fourth Six~Month Status Report for the Implementation of SFPLI Fehruarv ,-'0 I -5 2 RAI Question: Complete (RAI-1. Please provide the following: (Addressed in Reference 4)

Ref. 3) a) For level 1, specify how the identified location represents the HIGHER of the two points described in the NEI 12-02 guidance for this level.

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

Indicate on this sketch the portion of the level sensor measurement range that is sensitive to measurement of the fuel pool level, with respect to the Level 1 , Level 2, and Level 3 datum points.

Indicate on this sketch the elevation of the bottom opening of the gates that connect the two pools.

3 RAI Question: Complete (RAI-2. Please provide a clearly labeled (Addressed in Reference 8)

Ref. 3) sketch or marked-up plant drawing of the plan view of the s:FP area, depicting the Sf'P 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 read-out/disulav device.

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Limerick Generating Station. Units I and 2 Fourth Six-Month Status Report for the Implementation of SFPLI Fe b ruar J "'7

~ , 2015 4 RAI 0ur'stinn Complete (RAl-3, Please provide the following: (Addressed in Reference 8)

Ref. 3) 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 SJ<'P structures so as to support the level sensor assembly.

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Limerick Generating Station. Units l and 2 Fourth Six-Month Status Report for the Implementation of SFPLI Februar v 27, 2015 5 RAI Question: Complete (RAl-4, Please provide the following: (Addressed in Reference 8)

Ref. 3) 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 ec1uipment 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.

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Limerick Generating Station. Units l and 2 Fourth Six-Month Status Report for the Implementation of SFPLI Fe b ruar ',27 . "0 -

.:.. I ~

6 RAI Question: Complete (RAl-5. Please provide the following: (Addressed in Reference 8)

Ref. J) 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,

('.Onsisting of' level sensor eledronics, cabling, and readout devices will be designed and installed to address independence throngh 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.

7 RAI Question: Complete I

(RAI-6. Please provide the following: (Addressed in Reference 8)

Ref. J) 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 requirement'>

demonstrating that it'> capacity is sufficient to maintain the level indication function until offsite resource availability is reasonably assured.

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Limerick Generating Station. Units I and 2 Fourth Six-Month Status Report for the Implementation of SFPU F e b ruar V LI, '1015 1

8 RAJ 011t>.;;tion Complete (RAI-7. Please provide the following: (Addressed in Reference 8)

Ref. 3) a) An estimate of the expected instrument channel accuracy performance under both (a) normal SFP level conditions (approximately Level 1 or higher) and (b) at the BDB 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 point'i.

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.

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Limerick Generating Station, Units I and 2 Fourth Six~Month Status Report for the Implementation of SFPLI Fe bmar LI, ?015 1

9 RAT Clrn><;:tmn Sta11ed (RAl-8, Please provide the following: a) Westinghouse calibration procedure WNA-TP-Ref. 3) a) A description of the capability 04709-GEN, Rev. 4 and functional test procedure and provisions the proposed level WNA-TP-046 t:~-GEN. Rev. 5 describe the sensing equipment will have to capabilities and provisions of SFPI periodic testing enable periodic testing and and calibration. including in-situ testing.

calibration, including how this b) The level displayed by the channels will be capability enables the equipment to be tested in-situ. verified per the LGS administrative and operating b) A description of how such procedures. as recommended by Westinghouse testing and calibration will enable vendor technical manual WNA-G0-00127-GEN, the conduct of regular channel Rev. 3. If the level is not within the required checks of each independent accuracy per Westinghouse recommended tolerance channel against the other, and in WNA-TP-04709-GEN. channel calibration will against any other permanently- be performed.

installed SFP level c) Functional checks will be performed per instrumentation.

Westinghouse functionality test procedure WNA-c) A description of how functional checks will be performed, and the TP-04613-GEN at the Westinghouse recommended frequency at which they will be frequency. Calibration tests will be performed per conducted. Describe how Westinghouse calibration procedure WNA-TP-calibration tests will be performed, 04709-GEN at the Westinghouse recommended and the frequency at which they frequency.

will be conducted. Provide a In accordance with LGS maintenance and operating discussion as to how these programs, LGS will develop Preventive surveillances will be incorporated Maintenance (PM) tasks for calibration, functional into the plant surveillance test, and channel verification per Westinghouse program.

recommendations to ensure reliable. accurate and d) A description of what preventive maintenance tasks are continuous SFPI functionality prior to Startup from required to be performed during 2R 13 outage (Spring 2015).

normal operation, and the planned d) LGS will develop preventive maintenance tasks maximum surveillance interval for the SFPI per Westinghouse recommendation that is necessary to ensure that the identified in the technical manual WNA-G0-00127-channels are fully conditioned to accurately and reliably perform GEN to assure that the channels are fully their functions when needed. conditioned to accurately and reliably perform their functions when needed prior to Startup from the 2R 13 outage (Spring 2015 ).

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Limerick Generating Station, Units l and 2 Fourth Six-Month Status Report for the Implementation of SFPLI Februar LI, 2015 1

10 RAJ 01w<:tion Complete (RAI-9, Please provide the following: (Addressed in Reference 8)

Ref. 3) a) The specific location for the primary and backup instrument channel display.

b) If the primary or backup display location is other than the main control room, then provide justification for prompt accessibility to displays including primary and alternate route evaluation, habitability at display location(s),

continual resource availability for personnel responsible to promptly read displays, and provisions for communications with decision makers for the various SFP drain-down scenarios and external events.

c) The reasons justifying why the locations selected enable the information from these instrument<>

to be considered "promptly accessible" to various drain-down scenarios and external event<>.

11 RA! Question: Complete (RAI-10, Please provide the following: (Addressed in Reference 8)

Ref. 3) a) A list of the operating (both normal and abnormal response) procedures, calibration/test procedures, maintenance procedures, and inspection procedures that will be developed for nse of the S:FP instrumentation in a manner that addresses the order requirement<>.

b) A brief description of the specific technical objectives to be achieved within each procedure. If your plan incorporates the use of portable spent fuel level monitoring component<>, please include a description of the objective<> to be achieved with regard to the storage location and provisions for installation of the portable components when needed.

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Limerick Generating Station, Units I and 2 Fourth Six-Month Status Report for the Implementation of SFPLI Fe bruar J 0 7 ?015.

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12 RAI Question: Complete (RAI-1 L Please provide the following: (Addressed in Reference 8)

Ref. 3) a) Further information describing Previous note under items b and e has changed to the maintenance and testing program the licensee will establish the following:

and implement to ensure that Note: Initiate an Issue Report to enter the condition regular testing and calibration is into the Corrective Action Program. Identify the performed and verified by equipment out of service time is greater than the inspection and audit to specified allowed out of service time. develop and demonstrate conformance with design and system readiness implement an alternate method of monitoring, requirement~. Please include a determine the cause of the non-functionality. and the description of your plans for plans and schedule for restoring the instrumentation ensuring that necessary channel channel(s) to functional status.

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.

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Limerick Generating Station. Units l and 2 Fourth Six-Month Status Report for the Implementation of SFPLI February 27. 2015 Interim Staff Evaluation Open Items 01# Description Status I R Al Otwstion Started (RAI- Please provide the following: a) Complete redundant monitoring of the pools L a) A description of the operational will not be available when the gates are circumstan<*es under which the gates are installed. The gates are not normally installed.

Ref.

expected to be installed, and describe how

5) There is an existing procedure M-097-009 continuous back-up monitoring (e.g.,

direct visual observation) i" available (Cask Pit Gate Removal.- Installation, when the gates are installed. Maintenance and Movement of Fuel Pool Gates b) The elevation for the bottom of the gate Between Storage/ Repair Locations) to remove opening to demonstrate that both the and install the gates. To address the concern primary and backup S:FP instrument I when the gates may be installed. the procedure channels can simultaneously measure the M-097-009 will be revised to establish same Level 3 elevation.

administrative guidance/controls to follow the NEI 12-02 rev. I guidance for the 90-day out of service criterion.

b) The elevation for the bottom of the transfer pit for Limerick Generating Station (LGS) is -

8.75". Level 3 for LGS is revised to elevation 327' 11.32", which is slightly above the bottom of the transfer pit. rather than. the top of the Fuel rack elevation 327.Sft. This will provide assurance that both the primary and backup SFP level instrument channels can measure the same Level 3 elevation in both SFPs.

2 RAI Question: Complete (RAI- Please describe the impact of the (Addressed in Reference 7)

2. installation of the gate on the reliability of the SFP level instrumentation for each Ref.

s:FP, and what compensatory measures

5) would be taken to ensure reliable level indication in each SFP when the gate is installed.

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Limerick Generating Station. Units I and 2 Fourth Six-Month Status Report for the Implementation of SFPLI Fe bruary 27 . -?()J'i.

3 RA I ni1estion Complete (RAJ- Please provide additional information (Addressed in Reference 8)

4. describing how the final arrangement of the SFP instrumentation and ronting of Ref.

the cabling between the level instruments,

5) the electronics and the displays, meet"> the Order requirement to arrange the SFP level instrument channels in a manner that provides reasonable protection of the level indication function against missiles that may result from damage to the structure over the SFP.

4 RAI Question: Complete (RAI- For RAI 5(a) above (please refer to (Addressed in Reference 8)

6. RAI-3(a) in the Overall Integrated Plan Ref. Open Items Table), please provide the analyses used to verify the design 5) 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 effect<; that could accomvanv such seismic forces.

5 RAI Question: Complete (RAI- For each of the mounting attachments (Addressed in Reference 8)

7. required to attach SI~P level equipment Ref. to plant structures, please describe the design input-;, and the methodology that 5) was used to qualify the structural integrity of the affected structures /equipment.

6 RAI Question: Complete with this submittal.

(RAJ- For RAI #8 above, (please refer to RAI-4 For this RAI. all portions of this question were

9. in the Overall Integrated Plan Open completed in the previous submittal except for the Ref. Items Table), please provide the result" Westinghouse aging test.

for the selected methods, tests and

5) Westinghouse has completed their aging tests to age analyses utilized to demonstrate the qualification and reliability of the the system components to l 0 years. The tests were installed equipment in accordance with completed satisfactorily and the final test reports the Order rec1uirements. were reviewed and found acceptable by Limerick Generating Station.

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Limerick Generating Station, Units I and 2 Fourth Six-Month Status Report for the Implementation of SFPLI February 27. 20 15 7 l~AI Ot1t~-:t10n Complete (RAJ- Please provide the following: (Addressed in Reference 8) 14, a) The specific location for the primary Ref. and backup instrument channel display.

5) b) For any display 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.

8 RAI Question: Complete (RAJ- Please provide a list of the procedures (Addressed in Reference 8)

15. addressing operation (both normal and abnormal response), calibration, test, Ref.

maintenance, and inspection procedures

5) 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.

Note: RAis 3. 5. 8, 10, 11, 12.13 and 16 are not included in the Interim Staff Evaluation Open Items Table as they are duplicate to the RAis in Reference 3 and listed in the Overall Integrated Plan Open Item Table as RAis 2, 3, 4, 5, 6, 7. 8. and 11 respectively.

7 Potential Draft Safety Evaluation Impacts There are no potential impacts to the Draft Safety Evaluation identified at this time.

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Limerick Station. Units I and 2 Fourth Six-Month Status Report for the Implementation of SFPLI February 2015 8 References The following ,,,.,,n***~c support the updates to the Overall Integrated Plan described in this enclosure.

I. Exelon Generating Company. LLC. letter to USNRC. "Overall Integrated Plan in Response to March 12. 2012 Commission Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051 )... dated February 2013 (RS 032).

2. NRC Order Number EA-12-051. "Issuance of Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation," dated March 12, 2012.

3. USNRC letter to Exelon Generation Company, LLC, Limerick Generating Station. Units 1 and 2-Request For Additional Information RE: Overall Integrated Plan In Response to Order EA-12-051,

" Reliable Spent Fuel Pool Instrumentation" (TAC NOS. MF0854 and MF0855). dated June 24 2013.

4. Exelon Generating Company. LLC, Letter to USNRC. "Response to Request for Additional Information - Overall Integrated Plan in Response to Commission Order Modifying License Requirements for Reliable Spent Fuel Pool Instrumentation (Order No. EA-12-051 )", dated July 18, 2013, (RS-I 177).

5. USNRC letter to Exelon Generation Company. LLC, "Limerick Generating Station, Units I and 2 -

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 NOS. MF0854 and MF0855)". dated October 23. 2013.

6. First Six-Month Status Report for the Implementation of Order EA-12-051. Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation, dated August 28, 2013 (RS 122).

7. Second Six-Month Status Report for the Implementation of Order EA-12-051. Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation, dated February 28, 2014 (RS-14-022).

8. Third Six-Month Status Report for the Implementation of Order EA-12-051. Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation, dated August 28. 2014 (RS 200).

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