ML12284A130

McGuire Nuclear Station, Units 1 and 2 - Response to Request for Additional Information Regarding License Amendment Request Related to Measurement Uncertainty Recapture Power Uprate

ML12284A130
Person / Time
Site:	McGuire, Mcguire
Issue date:	09/27/2012
From:	Capps S D Duke Energy Carolinas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC ME8213, TAC ME8214
Download: ML12284A130 (27)

Text

Duke Contains sensitive security related information.

STEVEN D. CAPPS Duke Vice President t Energy Withhold from public disclosure per 10 CFR 2.390(d)(1)

McGuire Nuclear Station Duke Energy MG01 VP / 12700 Hagers Ferry Rd.Huntersville, NC 28078 980-875-4805 980-875-4809 fax Steven. Capps@duke-energy.

com September 27, 2012 10 CFR 50.90 U. S. Nuclear Regulatory Commission Washington, D.C. 20555 ATTENTION:

Document Control Desk

Subject:

Duke Energy Carolinas, LLC (Duke Energy)McGuire Nuclear Station, Units 1 and 2 Docket Nos. 50-369 and 50-370 Response to Request for Additional Information Regarding License Amendment Request Related to Measurement Uncertainty Recapture Power Uprate (TAC Nos. ME8213 and ME8214)This letter provides responses to a August 23, 2012 Nuclear Regulatory Commission (NRC)request for additional information (RAI questions 45 and 46) and a September 7, 2012 RAI (questions 47 through 53) related to a March 5, 2012 McGuire Nuclear Station (MNS) Units 1 and 2 License Amendment Request (LAR) submitted pursuant to 10 CFR 50.90 in support of a measurement uncertainty recapture (MUR) power uprate.The responses to questions 50 and 53 in the September 7, 2012 RAI are dependent on the implementation schedule for each Unit's MUR power uprate, High Pressure Turbine replacement, and Generator Stator/Exciter replacement.

MNS is re-evaluating the implementation schedule for Unit 1. Therefore, in order to ensure a complete and accurate response, MNS requests additional time to respond to questions 50 and 53. MNS anticipates that responses to RAI questions 50 and 53 will be provided by October 19, 2012.In addition, this letter provides the following:

• A revised response to NRC MUR LAR RAI question 23 originally provided in Enclosure 2 of the July 6, 2012 MNS MUR LAR RAI response.* Clarification and changes related to requests for withholding information from public disclosure per 10 CFR 2.390 provided in MNS MUR RAI responses dated May 29, 2012 and July 16, 2012.Contains sensitive security related information. )D Withhold from public disclosure per 10 CFR 2.390(d)(1) www. duke-energy.

corn Nuclear Regulatory Commission September 27, 2012 Page 2 NRC MUR LAR RAI questions 45 and 46 provided in the August 23, 2012 RAI and Duke Energy's responses are provided in Enclosure

1. NRC MUR LAR RAI questions 47 through 49, 51, and 52 provided in the September 7, 2012 RAI and Duke Energy's responses are provided in Enclosure

2. The revised response to MUR LAR RAI question 23 is provided in Enclosure 2 as part of the response to RAI question 52. Enclosure 3 provides a regulatory commitment described in this submittal.

Enclosure 4 provides tables referenced in the revised response to MUR RAI question 23 and the original response to RAI question 23 provided in correspondence dated July 6, 2012. Enclosure 5 provides revised MNS MUR LAR pages reflecting required changes described in this submittal.

Enclosures 6 through 8 provide clarification and changes related to requests for withholding information from public disclosure provided in MNS MUR LAR RAI responses dated May 29, 2012 and July 16, 2012. The information in Enclosures 6 through 8 is sensitive security-related information which Duke Energy requests be withheld from public disclosure per 10 CFR 2.390(d)(1).

Upon removal of Enclosures 6 through 8, this letter is uncontrolled.

As per RIS 2005-026 -Control of Sensitive Unclassified Nonsafeguards Information Related To Nuclear Power Reactors, an affidavit is not required for sensitive security-related information withheld under 10 CFR 2.390(d)(1).

The conclusions reached in the original determination that this LAR contains No Significant Hazards Considerations and the basis for the categorical exclusion from performing an Environmental/Impact Statement have not changed as a result of the RAI responses and other information provided in this submittal.

Please contact Kenneth L. Ashe at 980-875-4535 if additional questions arise regarding this LAR.Sincerely, S. D. Capps Enclosures Nuclear Regulatory Commission September 27, 2012 Page 3 cc: w/enclosures V. M. McCree Regional Administrator, Region II U.S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE, Suite 1200 Atlanta, GA 30303-1257 J. H. Thompson (addressee only)Project Manager (MNS)U.S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop 0-8 G9A Rockville, MD, 20852-2738 J. Zeiler NRC Senior Resident Inspector McGuire Nuclear Station cc: without enclosures W. L. Cox Ill, Section Chief North Carolina Department of Environment and Natural Resources Division of Environmental Health Radiation Protection Section 1645 Mail Service Center Raleigh, NC 27699-1645 Nuclear Regulatory Commission September 27, 2012 Page 4 OATH AND AFFIRMATION Steven D. Capps affirms that he is the person who subscribed his name to the foregoing statement, and that all the matters and facts set forth herein are true and correct to the best of his knowledge.

Steven D. Capp -Presint, McGuire Nuclear Station Subscribed and sworn to me:&,rJ: f, W ý ý- --'412' IJ)1 Date ry Public JAit liZp My commission expires: vrýDate Nuclear Regulatory Commission September 27, 2012 Page 5 bxc w/enclosures:

McGuire Master File (MG02DM)NRIAIELL (EC050)S. D. Capps (MG01VP)C. J. Morris III (RNPC32)H. D. Brewer (MG01VP)K. L. Ashe (MG01VP)K. L. Crane (MG01RC)J. J. Nolin (MG02MO)J. W. Bryant (MG01RC)D. C. Smith (MG0273)M. R. Wilder (MG0273)B. D. Meyer (MG02MO)M. C. Nolan (EC05P)S. M. Snider (MG05EE)J. W. Boyle (MG05SE)B.J. Horsley (EC04C)

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE Enclosure I McGuire Nuclear Station's Responses to MUR LAR RAI Questions 45 and 46 In the August 23, 2012 NRC Request for Additional Information By letter dated March 5, 2012 (Agencywide Documents Access and Management System (ADAMS), Accession No. ML12082A21 0), Duke Energy Carolinas, LLC (Duke Energy, the licensee), submitted a license amendment request (LAR) to change the McGuire Nuclear Station, Units 1 and 2 (McGuire 1 and 2), Technical Specifications (TSs). The proposed change revises the TSs to implement a measurement uncertainty recapture (MUR) power uprate for McGuire 1 and 2.The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the licensee's submittal and determined that the following additional information is needed in order to complete our review: NRC Question 45 Please provide the current operating EFPYs for McGuire 1 and 2 to assist in determining the margin available in the current Pressure-Temperature limits for 34 EFPY.McGuire Response to NRC Question 45 The operating Effective Full Power Years (EFPYs) for McGuire Nuclear Station (MNS) Units 1 and 2 as of September 17, 2012 is as follows: MNS Unit 1: 24.143 EFPY MNS Unit 2: 24.111 EFPY NRC Question 46 Please confirm that the ISI records for McGuire 1 and 2 show no Reactor Vessel (RV) surface flaws. If any RV surface flaws were detected, please characterize them.Page 1 of 3 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE McGuire Response to NRC Question 46 MNS performed a review of MNS Unit 1 and Unit 2 Refueling Outage (RFO) Inservice Inspection (ISI) Reports issued since initial startup of the Units. For Unit 1, the reports reviewed encompassed RFOs 1 EOC1 through 1 EOC21. For Unit 2, the reports reviewed encompassed RFOs 2EOC1 through 2EOC20. The purpose of the review was to determine if the inservice inspections documented in the reports identified any RV surface flaws that were reportable due to a failure to meet the acceptance criteria of the version of the ASME Section XI Code applicable to MNS Unit 1 and Unit 2 at the time of the inservice inspection.

MNS confirms that review of the Unit 1 RFO ISI Reports did not identify any reportable RV surface flaws. MNS review of the Unit 2 RFO ISI Reports identified two reportable RV surface flaws documented in the 1993 2EOC8 RFO ISI Report. The other Unit 2 RFO ISI reports reviewed did not identify any reportable RV surface flaws.The 2EOC8 RFO ISI Report identified the following RV surface flaws that were reportable due to a failure to meet the acceptance criteria of the version of the ASME Section Xl Code applicable to MNS Unit 2 at the time of the inservice inspection:

• An indication was noted in the RV interior consisting of a gouged area in the cladding of the lower vessel wall at 290 degrees circumferentially about 2 to 3 inches above the bottom head to bottom head spherical weld and approximately 2 feet up from the incore instrumentation nozzle. The length of the indication parallel to the inside surface is 3/8 inches and the depth is 3/32 inches. As per a manufacturer's drawing, the minimum dimension for clad thickness is 0.126 inches. Subsequent evaluation in 1993 concluded that, based upon manufacturer's information and ultrasonic testing (UT)/physical measurement, it did not appear the cladding had been breached and the indication was characterized as entirely in the cladding.

Conservatively assuming the cladding had been breached and considering the effects of corrosion on the RV base metal, the evaluation concluded that the RV minimum wall thickness requirements would still be met for the life of the vessel. In addition, the evaluation concluded the indication would not cause the Unit 2 RV to exceed the applicable ASME Code stress intensities and continued operation of the RV was acceptable.

Based upon the evaluation results, repair of the indication was not warranted.

Review of RV interior inspection results in Unit 2 RFO ISI Reports after 1993 did not identify any results which indicated the subject indication has degraded.* An indication was noted at approximately 129 to 130 degrees on the lower head to bottom head circumferential weld at the surface of the RV outer diameter.

The indication is planar, oriented transverse to the weld, and approximately 0.5 inches deep and 2.4 inches in length. Subsequent evaluation in 1993 concluded that the RV could Page 2 of 3 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE continue to operate for the life of the plant. Based upon the evaluation results, repair of the indication was not warranted.

In 1995, based upon new data, the subject indication was reclassified from an unacceptable surface connected planar flaw to an acceptable subsurface volumetric flaw. Inspection of the weld containing the flaw was performed in Unit 2 RFO 2EOC16 (Spring 2005) and the results were acceptable.

No changes to the Reactor Coolant System design or operating pressure were made as a part of the power uprate. The operating temperature changes are small and within design limits.The effect of changes in operating conditions due to MUR power uprate have been evaluated for the above two indications.

It has been determined that MUR power uprate causes no adverse impact to the structural evaluations performed for these indications.

Therefore, based on these evaluations, the Unit 2 RV can operate at MUR conditions for the life of the plant without repair to the indications.

Page 3 of 3 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE Enclosure 2 McGuire Nuclear Station's Responses to MUR LAR Request for Additional Information (RAI) Questions 47 Through 49 and 51 Through 52 In the September 7, 2012 NRC RAI By letter dated March 5, 2012 (Agencywide Documents Access and Management System (ADAMS), Accession No. ML1 2082A21 0), as supplemented, Duke Energy Carolinas, LLC (Duke Energy, the licensee), submitted a license amendment request (LAR) to change the McGuire Nuclear Station, Units 1 and 2 (McGuire 1 and 2), Technical Specifications (TSs). The proposed change revises the TSs to implement a measurement uncertainty recapture (MUR)power uprate for McGuire 1 and 2.The NRC staff has reviewed the licensee's response and determined that following additional information is needed to complete the safety evaluation:

NRC Question 47 For Prairie Island Nuclear Generating Plant (Prairie Island), the MUR power level is 1677 MWt.With a "Failed" Leading Edge Flow Meter (LEFM), the Prairie Island MUR power uprate allows operation at 1677 MWt until the next scheduled daily power calorimetric determination and a 7-day allowed outage time (AOT) at the Pre-MUR power level of 1650 MWt. The LAR for McGuire 1 and 2 is asking for 7-day operation with an out-of-service (OOS) allowance of 0.045% (compared to the Pre-MUR power level at Prairie Island) for a 7-day AOT. Provide justifications how the Prairie Island example is applicable for McGuire 1 and 2 MUR LAR.McGuire Response to NRC Question 47 As described in the McGuire (MNS) response to MNS MUR LAR RAI Question 49, MNS will implement a 72-hour AOT for a non-functional LEFM System without application of an OOS allowance of 0.045 percent. This is consistent with previous MUR power uprate applications approved by the NRC. With the agreement to implement a 72-hour AOT, MNS no longer references the Prairie Island example as a basis for an extended AOT.Page 1 of 7 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE NRC Question 48 Drift evaluations similar to the drift evaluation the licensee performed for the McGuire 1 and 2 LEFM AOT have been used by the industry to establish TS surveillance intervals, (e.g. fuel cycle extension from 18-months to 24-months).

However, it is not the established industry practice to rely only on drift evaluation for AOT determination when one or more instrument channels are inoperable.

Therefore, an evaluation using drift alone is not sufficient to justify extending an AOT. Please provide additional information to justify the 7-day LEFM AOT.McGuire Response to NRC Question 48 As described in the MNS response to MNS MUR LAR RAI Question 49, MNS is not requesting an AOT which would be extended in comparison to an AOT approved by the NRC for previous MUR power uprate applications.

Instead, consistent with previous applications, MNS will implement a 72-hour AOT for a non-functional LEFM System. The basis for the proposed 72-hour AOT, which is provided in the below response to RAI Question 49, does not rely solely on a drift evaluation.

NRC Question 49 The McGuire 1 and 2 MUR LAR is asking for 7 days plant operation with the above bounding secondary calorimetric uncertainty (SCU) when the LEFM is inoperable.

For previous measurement uncertainty recapture (MUR) power uprate applications, the NRC staff approved a similar AOT with the LEFM inoperable for maximum of 3 days, which is consistent with Cameron's analysis and recommendations to operate with a failed LEFM. An AOT of 3 days for repair or replacement of inoperable instrumentation and controls systems is an established practice in the nuclear power industry.

Please explain why a 7-days AOT at the higher power level is needed for McGuire 1 and 2, when the LEFM equipment that justifies operation at the higher power level is inoperable.

McGuire Response to NRC Question 49 MNS evaluation of Criterion 1 from ER-1 57P, Rev 8, described in Enclosure 2 of the MUR LAR dated March 5, 2012, the MNS response to MUR LAR RAI Question 20c provided in correspondence dated July 6, 2012, and the MNS response to MUR LAR RAI Question 44 provided in correspondence dated August 15, 2012 provided the basis for selection of a 7-day AOT when an LEFM System is not functional.

However, MNS will implement a 72-hour AOT for a non-functional LEFM System consistent with previous MUR power uprate applications approved by the NRC. The basis for the proposed 72-hour AOT, which is consistent with the basis provided for the 7-day AOT, is as follows: Page 2 of 7 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE* When an LEFM System is non-functional, signals from an existing ASME flow nozzle will be used as input to the Secondary Calorimetric portion of the Rated Thermal Power (RTP) calculation in place of the LEFM System. During normal LEFM operations, the signals from the ASME flow nozzles are calibrated to the LEFM signals and upon LEFM failure the ASME flow nozzle calibration is locked to the last good LEFM value.* A statistical analysis and review of drift data for plant instrumentation which will provide the ASME flow nozzle signals to the Secondary Calorimetric portion of the RTP calculation demonstrates instrumentation and RTP drift should be insignificant over a 72-hour AOT period. This indicates that, without application of a bias based upon a bounding value of RTP SCU, the MNS Units can be operated for 72-hours without exceeding the licensed RTP limit when the ASME Flow Nozzle signals are used as an input to the Secondary Calorimetric portion of the RTP calculation in place of the LEFM System.* A review of ASME Flow Nozzle fouling history demonstrates that fouling/de-fouling should not introduce significant error/drift over a 72-hour AOT period. This indicates that, without application of a bias based upon a bounding value of RTP SCU, the MNS Units can be operated for 72-hours without exceeding the licensed RTP limit when the ASME Flow Nozzle signals are used as an input to the Secondary Calorimetric portion of the RTP calculation in place of the LEFM System.* It is expected that most issues rendering an LEFM System non-functional could be resolved within a 72-hour AOT.* The NRC has approved a 72-hour AOT for previous MUR power uprate applications.

Reference NRC to Shearon Harris correspondence dated May 30, 2012 (Accession Number ML1 1356A096), NRC to Calvert Cliffs correspondence dated July 22, 2009 (Accession Number ML091820366), and NRC to Limerick correspondence dated April 8, 2011 (Accession Number ML1 10691095).

Based upon the above and as described in Enclosure 1 and Attachment 1 of Enclosure 2 of the MUR LAR dated March 5, 2012, a Selected Licensee Commitment (SLC) will be added to address functional requirements for the LEFMs and appropriate Required Actions and Completion Times when an LEFM is not functional.

If a non-functional LEFM is not restored to functional status within 72-hours, then within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> the Unit will be reduced to no more than 3411 MWt (the previously licensed rated thermal power). These SLC changes are not provided as part of the MNS MUR LAR or this RAI response but will be controlled using the 10 CFR 50.59 process. The above SLC description supersedes the SLC description and related AOT Page 3 of 7 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE text discussed in the MNS evaluation of Criterion 1 from ER-1 57P, Rev 8, as described in Enclosure 2, Pages E2-6 and E2-7, of the MUR LAR dated March 5, 2012.As part of the MNS evaluation of Criterion 1 from ER-1 57P, Rev 8, described in Enclosure 2 of the MUR LAR dated March 5, 2012, the MNS response to MUR LAR RAI Question 20c provided in correspondence dated July 6, 2012, and the MNS response to MUR LAR RAI Questions 43 and 44 in correspondence dated August 15, 2012, MNS indicated that, for a 7-day AOT, additional conservatism would be added by applying a bias based upon the bounding value of 0.045% RTP SCU. This bias would be applied to the ASME Flow Nozzle signals used as an input to the Secondary Calorimetric portion of the RTP calculation when the LEFM System is not functional.

Also, as described in the response to RAI Question 43 and documented in Enclosure 3 of a MNS MUR LAR RAI response letter dated August 15, 2012, for a 7-day AOT, McGuire committed to adding a SLC requirement to perform an analysis on a MNS Unit's LEFM System on an every other outage refueling frequency.

This analysis would include updating the bounding SCU data used to establish the bias based upon the bounding value of RTP SCU. As described above, MNS will implement a 72-hour AOT when an LEFM System is non-functional.

Since the ASME Flow Nozzle fouling/de-fouling related drift, instrumentation related drift, and RTP drift over a 72-hour AOT would be insignificant, it is not necessary to apply a bias to ensure the licensed RTP remains within the allowed limit while an LEFM System is non-functional.

This is consistent with previous MUR power uprate applications approved by the NRC. Given that MNS will not apply a bias for a 72-hout AOT, the commitment described in the response to RAI Question 43 and documented in Enclosure 3 of the MNS MUR LAR RAI response letter dated August 15, 2012 is withdrawn.

A revised Enclosure 2, Pages E2-6 and E2-7, of the MUR LAR dated March 5, 2012 are provided in Enclosure 5 to reflect changes related to this RAI response.NRC Question 50 In the letter by Duke Energy dated July 16, 2012, in response to the NRC staff RAI question 40, the licensee stated that the degraded voltage relay settings at the safety-related buses will not be changed under post-MUR uprate conditions.

Therefore, any changes in switchyard voltages after MUR implementation will be dependent on plant loading. Any change in these post-MUR switchyard voltages will be discussed and communicated with the TSO [Transmission System Operator]

prior to implementation of the MUR.Provide assurance, including the use of a regulatory commitment as appropriate, that any changes in the switchyard voltages required (so as not to impact the degraded voltage relay Page 4 of 7 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE settings), corresponding to the post-MUR uprate and HP Turbine replacement conditions, will be evaluated prior to the implementation of MUR uprate.McGuire Response to NRC Question 50 As described in the cover letter, the response to this question will be provided in a future submittal.

NRC Question 51 In the letter by Duke Energy dated July 6, 2012, in response to the NRC staff RAI question 4, the licensee stated that certain reactor vessel level indication reactor temperature detectors (RTDs) were previously determined to be a degraded/non-conforming condition, dependent on their installed location.

In addition, one of three McGuire 1 pressurizer level transmitters was determined to be inoperable for post-accident monitoring, but operable for other required normal operation functions.

Resolution of these existing conditions, which are being tracked in the corrective action program, are applicable for current operating conditions and conditions after MUR implementation.

Provide assurance, including the use of a regulatory commitment as appropriate, that the above mentioned RTDs and the pressurizer level transmitter will return to the operable condition prior to the implementation of MUR power uprate.McGuire Response to NRC Question 51 This RAI response provides the following regulatory commitment.

This commitment is documented in Enclosure 3: Unit 2 reactor vessel level indication RTDs (2NCRD8360 and 2NCRD8430) and a Unit 1 pressurizer level transmitter (1 NCLT5170), previously identified in the July 6, 2012 MNS response to MNS MUR LAR RAI Question 4 as being in a degraded/non-conforming condition and an inoperable condition respectively, will be returned to an operable condition prior to implementation of the MUR power uprate on the applicable MNS Unit.Page 5 of 7 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE NRC Question 52 In the letter by Duke Energy dated July 6, 2012, the response to RAI question 23 appears to be missing a table that is needed to complete this response.

Please provide this table.McGuire Response to NRC Question 52 MNS MUR LAR RAI question 23 was provided as part of an NRC RAI dated June 6, 2012.Duke Energy provided a response to RAI question 23 in Enclosure 2 of a letter dated July 6, 2012. The tables referenced in the RAI question 23 response were inadvertently omitted from the response submittal.

This omission has been entered into the MNS corrective action program for cause evaluation and corrective action. These tables are provided in Enclosure 4.The response to RAI question 23 provided in Enclosure 2 of the letter dated July 6, 2012 indicated all changes required to reflect the MUR conditions were being incorporated in the Checworks models and the related databases were undergoing formal validation.

As stated in that response, a preliminary wear rate analysis was performed to assess the impact of the MUR on susceptible Flow Accelerated Corrosion (FAC) components and final data, which would be available around August 31, 2102, was expected to confirm the preliminary results. A revised response to MNS MUR LAR RAI question 23 is provided below incorporating MUR related changes, final data, and validated results into the MNS FAC program's Checworks models and databases.

The final data confirms the preliminary results of the wear rate analysis discussed in the original response to RAI question 23. The below revised response replaces the original response to RAI question 23 provided in Enclosure 2 of the July 6, 2012 MNS MUR LAR RAI response submittal.

Revised Response to NRC Question 23: As a result of plant and industry experience with pipe degradation in process systems, a FAC program was developed at MNS. The purpose of the program is to monitor piping systems that are subject to FAC degradation, and to mitigate pipe wall loss. The FAC program is based on the guidance of EPRI NSAC-202L-R3, Recommendations for an Effective Flow-Accelerated Corrosion Program.MNS uses the EPRI Checworks Steam/Feedwater Application (SFA) monitoring software to model operating conditions, material data, and UT inspection data to provide a calculated estimate of component wear. The thermodynamic changes associated with the MUR will impact corrosion rates for components located on FAC susceptible systems. All changes required to reflect the MUR conditions have been incorporated in the Checworks models and the final results and databases have been validated.

Page 6 of 7 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE A wear rate analysis has been performed to assess the impact of the MUR on susceptible FAC components and sample results are shown in the Tables in Enclosure

4. They provide a comparison of the pre-MUR and post-MUR wear rates. Per this analysis, the increase in wear rates due to the MUR power uprate is considered minor and the existing FAC Program is adequate to incorporate the updated predictions.

The wear rate analysis results described in the above revised response to RAI question 23 are consistent with the preliminary results discussed in the original RAI question 23 response provided on July 6, 2012. Therefore, the tables in Enclosure 4 are applicable references for both the tables described in revised response and the original response to RAI question 23.NRC Question 53 In the letter by Duke Energy dated March 5, 2012, it states that: Duke Energy requests approval of this amendment request by October 5, 2012 to support implementation during the Unit 2 Fall 2012 refueling outage. Implementation of the approved amendment on Unit 1 is scheduled to occur during the Spring 2013 refueling outage.The NRC staff typically requires that license amendments are implemented within 30 days of issuance of the amendment.

Please provide additional clarification and justification for your proposed time frame for implementation of the license amendment.

McGuire Response to NRC Question 53 As described in the cover letter, the response to this question will be provided in a future submittal.

Page 7 of 7 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE Enclosure 3 List of Commitments Commitment I Commitment Date-I-Unit 2 reactor vessel level indication RTDs (2NCRD8360 and 2NCRD8430) and a Unit 1 pressurizer level transmitter (1 NCLT5170), previously identified in the July 6, 2012 MNS response to MNS MUR LAR RAI Question 4 as being in a degraded/non-conforming condition and an inoperable condition respectively, will be returned to an operable condition prior to implementation of the MUR power uprate on the applicable MNS Unit.Prior to implementation of the MUR power uprate on the applicable MNS Unit.

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE Enclosure 4 Tables Referenced In the Revised Response to MUR LAR RAI Question 23 Provided In Enclosure 2 and the Original Response to RAI Question 23 provided on July 6, 2012 MNS Unit I Table Supporting The Response To Question #23 Sample of Unit I Components with Highest Increase In Wear Rate Due to MUR CHECWORKS T M SFA-Used to Predict Post-MUR Wear Rate' (at 101.7% Power) Which is Compared to Pre-MUR Measured Wear Rate (at 100% Power)Wear Rate (mils/cycle)

Pre- Post- Average increase MUR MUR in wear rate due CHECWORKS SFA Run Component (100% (101.7% to MUR Definition System Name Power) Power) (mils/cycle)

Comments Heater 1HC037P 2.186 2.312 Remaining susceptible portion of this HC1 D:HPT to C HTR Bleed 0.204 run definition scheduled for piping 1HC031E-T26 4.938 5.22 replacement by 1EOC23 HS3D:MSR Drains u/s MSR Drain 1HS0686P 0.826 0.877 0.068 CV 1 HS0306E 1.39 1.475 CFT2/D: B to A HTR Feedwater ICF134P 0.682 0.73 0.065 1CF85E 1.169 1.251 CFT1/D: FeedPMP to B 1CF46P 0.686 0.734 HRFeedwater 0.062 1CF129E 1.095 1.171 0.062 CMT3D:E to D HTR Condensate 1CM199P 1.393 1.427 0.046 1CM182E 2.388 2.446 CMT4D: D to C HTR Condensate 1CM215E 1.843 1.901 0.045 1CM264P 0.983 1.014 HB2D:lst stage MSR Heater 1HB115E 1.012 1.043 0.035 reheat Bleed 0.035 1HB167P 1.327 1.366 HS4D: MSR Drains d/s MSR Drain 1HS0918E 0.557 0.591 0.032 CV__ 1HS0330P 0.482 0.511 1HW008P 0.321 0.347 HW1 D: A to B HTRS Heater 0.025 Drain 1 HW094E 0.482 0.505 HS1 D-1 st Stage drain MSR Drain 1 HS0771 E 0.403 0.424 0.018 1 HS0232P 0.273 0.287 HW6D:D to E HTRS Heater 1 HW570E 0.89 0.904 0.012 Drain 1HW494P 0.602 0.611 CMT1D:F HTR to CBP Condensate 1CM080E 0.831 0.84 0.009 1CM007P 0.753 0.761 HW5D-.C PMP to Heater 1 HW370P 0.399 0.405 0.008 Condensate Drain0.8 1 HW441E 0.739 0.748 CMT2D:CBP to E HTR Condensate 1CM158P 0.742 0.749 0.007 1CM131E 0.64 0.646 Heater 1HW154E 0.826 0.833 HW2D:B HTR to C Tank 0.006 Drain 1HW199P 0.59 0.595 1 1 Page 1 of 7 MNS Unit I Table Supporting The Response To Question #23 Sample of Unit I Components with Highest Increase In Wear Rate Due to MUR CHECWORKS T M SFA-Used to Predict Post-MUR Wear Rate' (at 101.7% Power) Which is Compared to Pre-MUR Measured Wear Rate (at 100% Power)Wear Rate (mils/cycle)

Pre- Post- Average increase MUR MUR in wear rate due CHECWORKS SFA Run Component (100% (101.7% to MUR Definition System Name Power) Power) (mils/cycle)

Comments 1CM309P 0.835 0.841 000 CM2D: AFTER HW Condensate 1CM356E 0.754 0.759 HW4D:C TNK to C Heater 1HW334P 0.394 0.403 0.001 Pump Drain0.1 1 HW343E 0.73 0.746 HW7D:E to F HTRS Heater 1HW708P 0.643 0.644 0.001 Drain 1HW605E 0.964 0.965 1. Predicted Post-MUR wear rate at the conclusion of Unit 1 Fuel Cycle 23, currently scheduled to begin on approximately April 20, 2013 and end on approximately September 20, 2014.Page 2 of 7 MNS Unit I Table Supporting The Response To Question #23 Sample of Unit I Components with Pre-MUR Highest Predicted Wear Rates CHECWORKS T M SFA-Used to Predict Post-MUR Thickness 2 Which is Compared to Pre-MUR Measured Thickness'

.........

~ ~ ~ ~ ~ Rti o,,, P,, : :I .,.~I ~Measured K~Pre-MUR

~ Post-MUR ,Thickness 1to Me~asured

.~Predicted Post-U Thickness I,- Thickness, P rdected i me of Unit n (inhcnes)sice), Thickness i ,t,:'1 BBID:BB TANK DRAIN 1BB055E-T18 90 Degree Elbow 4.5 0.237 0.203 0.196 1.04 EOC-16 BB1 D:BB TANK DRAIN 1 BB078E-T20 90 Degree Elbow 4.5 0.237 0.209 0.198 1.06 EOC-16 CFTI/D-PMP-B HTR 361 1CF3E-T20 45 Degree Elbow 24 1.219 1.161 1.155 1.01 EOC-20 CFT1/D-PMP-B HTR 361 1CF21E-T03 45 Degree Elbow 24 1.219 1.144 1.131 1.01 EOC-16 CFT2/D-B-A HTR 402F 1CF108E-T52 180 Degree Elbow 22 1.125 1.087 1.073 1.01 EOC-15 CFT2/D-B-A HTR 402F 1CF133E-T53 180 Degree Elbow 22 1.125 1.056 1.041 1.01 EOC-14 CFT3/D-A HTR-SG 440F 1CF115E-T75 180 Degree Elbow 22 1.125 1.199 1.179 1.02 EOC-17 CFT3/D-A HTR-SG 440F 1CF258AT-T78 Tee U/S Main 18 0.938 0.833 0.818 1.02 EOC-17 CM2D:AFTER HW W/DATA 1CM319T-T21 Tee D/S Main 36 0.750 0.739 0.729 1.02 EOC-15 CM2D:AFTER HW W/DATA 1CM340E-T6 45 Degree Elbow 24 0.688 0.664 0.659 1.01 EOC-19 CMT1 D:F HTR t CBP 203 1CM083E-T82 90 Degree Elbow 20 0.375 0.331 0.327 1.01 EOC-20 CMT2D:CBP t E HTR 205 1CM143E-T72 90 Degree Elbow 30 0.625 0.623 0.620 1.00 EOC-20 CMT3D:E to D htrs 250 1CM187E-T34 180 Degree Elbow 18 0.500 0.462 0.456 1.01 EOC-21 CMT3D:E to D htrs 250 1CM184E-T36 90 Degree Elbow 16 0.500 0.450 0.427 1.05 EOC-12 CMT4D: D to C htr 288 1CM259E-T30 180 Degree Elbow 16 0.540 0.457 0.439 1.04 EOC-16 CMT4D: D to C htr 288 1 CM255E-T31 180 Degree Elbow 16 0.527 0.468 0.450 1.04 EOC-16 CMT5D:C HTR to HW 357 1 CM277AE-T39 180 Degree Elbow 16 0.500 0.476 0.456 1.04 EOC-12 CMT5D:C HTR to HW 357 1CM298E-T51 90 Degree Elbow 16 0.500 0.464 0.459 1.01 EOC-18 HA2D:STM FM RH W/DAT 1 HA335E-T27 90 Degree Elbow 8.625 0.322 0.273 0.266 1.03 EOC-19 HA2D:STM FM RH W/DAT 1HA464P-T96 Pipe 8.625 0.322 0.304 0.304 1.00 EOC-19 HA3D:BLD-RHTS W/DATA 1HA131P-T86 Pipe 10.75 0.365 0.314 0.305 1.03 EOC-19 HA3D:BLD-RHTS W/DATA 1 HA166P-T84 Pipe 8.625 0.322 0.251 0.235 1.07 EOC-17 HB1D:HPT-B HTS W/DAT 1HB330E-T11 90 Degree Elbow 14 0.375 0.251 0.141 1.78 EOC-16 HB1D:HPT-B HTS W/DAT 1HB337P-T41 Pipe 14 0.375 0.266 0.176 1.51 EOC-11 HB2D:STM FM RH W/DAT 1HB167E-T15 90 Degree Elbow 6.625 0.280 0.271 0.237 1.14 EOC-10 Page 3 of 7 MNS Unit I Table Supporting The Response To Question #23 Sample of Unit I Components with Pre-MUR Highest Predicted Wear Rates CHECWORKS T M SFA-Used to Predict Post-MUR Thickness 2 Which is Compared to Pre-MUR Measured Thickness' Nominal",'Pipe:Size (inches) Thickniess (inches)Pre-MURi Thickness*.Jinches),-Ratio 6f PreMUR Measured ,'Post-MUR

~Thickness to Predicted

! Post-MUR , ,,Thickness Predicted, Tlme of Unit I (inches) I Thickness.'

I .ospection3 HB2D:STM FM RH W/DAT 1HB314E-T04 90 Degree Elbow 6.625 0.280 0.269 0.229 1.17 EOC-10 HC1D:HPT-C HTRS W/DA 1HC035E-T06 90 Degree Elbow 30 0.375 0.328 0.254 1.29 EOC-14 HC1D:HPT-C HTRS W/DA 1HC072N-T41A Inlet Nozzle 16 0.500 0.444 0.370 1.2 EOC-16STG DRN w/DAT 1HS0266P-T122 Pipe 6.625 0.280 0.256 0.251 1.02 EOC-18 HS1D-1 STG DRN w/DAT 1HS0579E-T049 90 Degree Elbow 5.563 0.258 0.232 0.220 1.05 EOC-17 HS2D-2 STG DRN w/DAT 1 HS0372E-T091 90 Degree Elbow 6.625 0.432 0.393 0.387 1.02 EOC-20 HS2D-2 STG DRN w/DAT 1 HS0935T-T073 (D/S) .Tee 6.625 0.432 0.376 0.369 1.02 EOC-20 HS3D-MSR DRN TO CV 1 HS01 31 E-T056 90 Degree Elbow 8.625 0.322 0.296 0.284 1.04 EOC-17 HS3D-MSR DRN TO CV 1 HS0473T-T079 Tee 8.625 0.322 0.280 0.267 1.05 EOC-17 HS4D: MSR DRN DIS CV 1HS0163E-T067 90 Degree Elbow 8.625 0.322 0.308 0.303 1.02 EOC-16 HS4D: MSR DRN D/S CV 1HS0329E-T063 90 Degree Elbow 8.625 0.322 0.264 0.257 1.03 EOC-14 HW1 D:A TO B HTRS 1HW027E-TO60A 90 Degree Elbow 6.625 0.280 0.254 0.246 1.03 EOC-13 HW1D:A TO B HTRS 1HW090E-T108 90 Degree Elbow 6.625 0.280 0.254 0.252 1.01 EOC-20 HW2D:B HTR TO C TANK 1HW145E-T088D 90 Degree Elbow 8.625 0.322 0.309 0.300 .1.03 EOC-16 HW2D:B HTR TO C TANK 1HW212E-T027 90 Degree Elbow 8.625 0.322 0.289 0.285 1.01 EOC-20 HW3D:C DRAIN & VENT 1 HW271 E-T054 180 Degree Elbow 10.75 0.365 0.340 0.333 1.02 EOC-20 HW3D:C DRAIN & VENT 1HW268E-T056 180 Degree Elbow 10.75 0.365 0.325 0.318 1.02 EOC-20 HW4D:C TKS-C PUMPS 1HW335E-T102 90 Degree Elbow 16 0.375 0.390 0.379 1.03 EOC-13 HW4D:C TKS-C PUMPS 1 HW351 E-T104 90 Degree Elbow 16 0.375 0.382 0.371 1.03 EOC-13 HW5D:C PUMP-CM SYS 1CM372E-T53 90 Degree Elbow 20 0.594 0.596 0.588 1.01 EOC-16 HW5D:C PUMP-CM SYS 1HW415T-T045 (D/S) Tee D/S Main 12.75 0.375 0.343 0.337 1.02 EOC-18 HW6D:D TO E HTRS 1HW484E-T038A 90 Degree Elbow 6.625 0.280 0.255 0.246 1.04 EOC-16 HW6D:D TO E HTRS 1 HW521 E-T037 90 Degree Elbow 6.625 0.280 0.271 0.267 1.01 EOC-20 HW7D:E TO F HTRS 1HW624E-T017 90 Degree Elbow 6.625 0.280 0.252 0.247 1.02 EOC-20 HW7D:E TO F HTRS 1HW726E-T015 90 Degree Elbow 6.625 0.280 0.259 0.248 1.04 EOC-16 1. Measured thickness at the time of Unit 1 inspection.

2. Predicted Post-MUR thickness at the conclusion of Unit 1 Fuel Cycle 23, currently scheduled to begin on approximately April 20, 2013 and end on approximately September 20, 2014.3. Inspected after the end of the Unit 1 Fuel Cycle (EOC) indicated.

Page 4 of 7 MNS Unit 2 Table Supportinq The Response To Question #23 Sample of Unit 2 Components with Highest Increase In Wear Rate Due to MUR CHECWORKS T M SFA-Used to Predict Post-MUR Wear Rate 1 (at 101.7% Power) Which is Compared to Pre-MUR Measured Wear Rate (at 100% Power)Wear Rate (mils/cycle)

Pre- Post- Average increase MUR MUR in wear rate due CHECWORKS SFA Run Component (100% (101.7% to MUR Definition System Name Power) Power) (mils/cycle)

Comments There are only six remaining 2HC024E-T04 7.136 7.691 susceptible components in this run HC1 0: HPT to C HTR 0.368 definition and all are currently Bleed 2HC023E scheduled for replacement by 2.328 2.509 2EOC23 These components (1st stage MSR 2HM076E 1.031 1.328 reheat piping) are scheduled for Heater replacement prior to MUR uprate in Bleed refueling outage 2EOC21 (current scheduled outage start date is 2HM045P 0.817 1.053 September 15, 2012).CFT1/D: FeedPmp to B Feedwater 2CF10E-T06 1.419 1.54 0.124 HTR 2CF103P 1.487 1.614 CFT2/D:B to A HTR Feedwater 2CF112E 1.26 1.367 0.100 2CF84P 1.09 1.183 2HS0417E-HS1 D: 1st stage drain MSR Drain T58A 0.7 0.797 0.060 2HS0056P 0.134 0.157 HS3D:MSR Drains u/s MSR Drain 2HS0317E 1.662 1.746 0.056 CV 2HS0119P 0.562 0.59 HW1 D:A to B HTR Heater 2HW066E 0.764 0.801 0.035 Drain 2HWO18P 0.661 0.693 2HW535E-HW6D:D to E HTR Heater T034A 1.087 1.124 0.031 Drain 2HW494P 0.735 0.759 HS4D: MSR Drains d/s MSR Drain 2HS1141E 0.448 0.471 0.022 CV 2HS0705P 0.387 0.407 HW2D: B HTR to C drain Heater 2HW178E 1.35 1.375 0.021 tnk Drain 2HW123P 0.912 0.929 2HW343E-HW4D:C TNK to C pump Heater T104 0.688 0.71 0.018 Drain 2HW337P 0.409 0.422 HW5D:C PMP to Heater 2HW408E 0.951 0.97 0.017 Condensate Drain0.1 Condensate Drain 2CM380P 0.674 0.688 1. Predicted Post-MUR wear rate at the conclusion of Unit 2 Fuel Cycle 22, currently scheduled to begin on approximately October 22, 2012 and end on approximately March 8, 2014.Page 5 of 7 MNS Unit 2 Table SuDporting The Response To Question #23 Sample of Unit 2 Components with Pre-MUR Highest Predicted Wear Rates CHECWORKS T M SFA-Used to Predict Post-MUR Thickness 2 Which is Compared to Pre-MUR Measured Thickness',Nominal :~Thickness (inches)BB1 D: BB TK DN W/DAT 2BB072T-T016 Tee U/S Main 4.5 0.237 0.201 0.174 1.16 EOC-8 B11 D: BB TK DN W/DAT 2BB073P-T017 Tee DIS Main Ext 4.5 0.237 0.226 0.203 1.11 EOC-8 CFTI/D-PMP-B HTR 361 2CF2E-T01 45 Degree Elbow 24 1.219 1.095 1.079 1.01 EOC-16 CFTI/D-PMP-B HTR 361 2CF22E-T43 45 Degree Elbow 24 1.219 1.099 1.069 1.03 EOC-1 1 CFT3/D-A HTR-SG 440F 2CF301 E-T76 90 Degree Elbow 18 0.938 0.820 0.816 1.00 EOC-20 CFT3/D-A HTR-SG 440F 2CF458E-T71 90 Degree Elbow 18 0.938 0.874 0.867 1.01 EOC-19 CM2D:AFTER HW W/DAT 2CM319T-T21 Tee U/S Main 36 0.750 0.740 0.725 1.02 EOC-15 CM2D:AFTER HW W/DAT 2CM350E-T13 180 Degree Elbow 30 0.625 0.608 0.596 1.02 EOC-16 CMT1 D-Fhtr to CBP 210 2CM002E-T81 90 Degree Elbow 16 0.375 0.372 0.363 1.02 EOC-18 CMT2D:CBP t E htr 212 2CM113E-T77 Expanding Elbow 20 0.375 0.636 0.609 1.04 EOC-11 CMT2D:CBP t E htr 212 2CM124T-T65 (D/S) Tee D/S Main 30 0.625 0.621 0.602 1.03 EOC-11 CMT3D:Ehtr t Dhtr 263 2CM184E-T36 45 Degree Elbow 16 0.500 0.490 0.487 1.01 EOC-20 CMT4D: D to C htr 296 2CM21 1 E-T57A 90 Degree Elbow 16 0.500 0.482 0.470 1.03 EOC-16 CMT4D: D to C htr 296 2CM259E-T30 180 Degree Elbow 18 0.500 0.440 0.421 1.05 EOC-1 5 CMT5D:C htr t HW 361 2CM293E-T41 180 Degree Elbow 16 0.500 0.478 0.459 1.04 EOC-14 CMT5D:C htr t HW 361 2CM279P-T45 Pipe 16 0.500 0.468 0.461 1.02 EOC-14 HAl D: HPToHTR W/DATA 2HA001N-T46A Exit Nozzle 14 0.500 0.424 0.374 1.13 EOC-18 HA1 D: HPT-HTR W/DATA 2HAO05N-T45A Exit Nozzle 14 0.500 0.371 0.321 1.16 EOC-18 HA2D:SM FM RHT W/DAT 2HA335E-T26 90 Degree Elbow 8.625 0.322 0.230 0.219 1.05 EOC-19 HA2D:SM FM RHT W/DAT 2HA334E-T27 90 Degree Elbow 8.625 0.322 0.246 0.235 1.05 EOC-19 HA3D: BLD-RHTR W/DAT 2HA033E-T64 45 Degree Elbow 10.750 0.365 0.249 0.239 1.04 EOC-20 HA3D: BLD-RHTR W/DAT 2HA068P-T81 Pipe 8.625 0.322 0.295 0.255 1.16 EOC-14 HB1 D: HPT-HTR W/DAT 2HB317T-T43 Tee U/S Main 20 0.375 0.258 0.218 1.18 EOC-20 HB1 D: HPT-HTR W/DAT 2HB355N-T44A Inlet Nozzle 14 0.500 0.610 0.589 1.04 EOC-20 HB2D:SM FM RHT W/DAT 2HB314E-T04 90 Degree Elbow 6.625 0.280 0.197 0.188 1.05 EOC-20 Page 6 of 7 MNS Unit 2 Table Supporting The Response To Question #23 Sample of Unit 2 Components with Pre-MUR Highest Predicted Wear Rates CHECWORKS T M SFA-Used to Predict Post-MUR Thickness 2 Which is Compared to Pre-MUR Measured Thickness' HB2D:SM FM RHT WIDAT 2HB313E-T14 90 Degree Elbow 6.625 0.280 0.400 0.350 1.14 EOC-9 HC1D: HPT-HTR W/DATA 2HC021T-T30 (BR/SE) Tee Branch 20 0.375 0.302 0.126 2.40 EOC-9 HC1 D: HPT-HTR W/DATA 2HC021T-T30 Tee U/S Main 30 0.375 0.275 0.247 1.11 EOC-20 HSID:I Stg Drn w/Dat 2HS0070E-T54A 90 Degree Elbow 5.563 0.258 0.238 0.226 1.05 EOC-10 HS1D:1 Stg Dm w/Dat 2HS0417E-T58A 90 Degree Elbow 5.563 0.258 0.236 0.228 1.04 EOC-14 HS2D:2 Stg Drn w/Dat 2HS0352T-T077 Tee U/S Main 6.625 0.432 0.400 0.374 1.07 EOC-10 HS2D:2 Stg Dmn w/Dat 2HS0524E-T075 90 Degree Elbow 6.625 0.432 0.371 0.351 1.06 EOC-12 HS3D:MSR Drns US CV 2HS0306E-T081 90 Degree Elbow 8.625 0.322 0.311 0.299 1.04 EOC-17 HS3D:MSR Dmns US CV 2HS0689E-T069C 90 Degree Elbow 8.625 0.322 0.289 0.262 1.10 EOC-1 1 HS4D: MSR DRNS d/s cv 2HS0502E-T065 90 Degree Elbow 8.625 0.322 0.314 0.311 1.01 EOC-17 HS4D: MSR DRNS dis cv 2HS0704E-T068 90 Degree Elbow 8.625 0.322 0.306 0.302 1.01 EOC-1 5 HW1D:A-B HTR W/DATA 2HWO16E-T062D 90 Degree Elbow 6.625 0.280 0.239 0.230 1.04 EOC-14 HW1D:A-B HTR W/DATA 2HW099E-TO60C 90 Degree Elbow 6.625 0.280 0.252 0.248 1.02 EOC-18 HW2D:BHTR-C TK W/DAT 2HW139E-T088A 90 Degree Elbow 8.625 0.322 0.270 0.261 1.03 EOC-17 HW2D:BHTR-C TK W/DAT 2HW156E-T025A 90 Degree Elbow 8.625 0.322 0.300 0.284 1.06 EOC-14 HW3D:CDRN&VNT W/DAT 2HW276E-T077B 90 Degree Elbow 10.75 0.365 0.354 0.349 1.01 EOC-19 HW3D:CDRN&VNT W/DAT 2HW278E-T077A 45 Degree Elbow 10.75 0.365 0.331 0.327 1.01 EOC-19 HW4D:C TK-C PM W/DAT 2HW335E-T103 90 Degree Elbow 16 0.375 0.350 0.346 1.01 EOC-18 HW4D:C TK-C PM W/DAT 2HW343E-T104 90 Degree Elbow 16 0.375 0.343 0.339 1.01 EOC-18 HW5D:C PM-CM W/DATA 2CM372E-T53 90 Degree Elbow 20 0.594 0.640 0.637 1.00 EOC-20 HW5D:C PM-CM W/DATA 2HW360E-T87 90 Degree Elbow 12.75 0.375 0.342 0.337 1.01 EOC-18 HW6D:D-E HTR W/DATA 2HW485E-T038B 90 Degree Elbow 6.625 0.280 0.258 0.247 1.04 EOC-1 5 HW6D:D-E HTR W/DATA 2HW572E-T033A 90 Degree Elbow 6.625 0.280 0.247 0.229 1.08 EOC-1 1 HW7D:E-F HTR W/DATA 2HW726E-TO15A 90 Degree Elbow 6.625 0.280 0.248 0.246 1.01 EOC-20 HW7D:E-F HTR W/DATA 2HW729E-TO15B 90 Degree Elbow 6.625 0.280 0.255 0.253 1.01 EOC-20 1. Measured thickness at the time of Unit 2 inspection.

2. Predicted Post-MUR thickness at the conclusion of Unit 2 Fuel Cycle 22, currently scheduled to begin on approximately October 22, 2012 and end on approximately March 8, 2014.3. Inspected after the end of the Unit 2 Fuel Cycle (EOC) indicated.

Page 7 of 7 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REGULATION REGARDING A MCGUIRE LICENSE AMENDMENT TO SUPPORT A MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE Enclosure 5 Revisions to Paaes In MNS MUR LAR Dated March 5. 2012 Enclosure 2

SUMMARY

OF RIS 2002-03 REQUESTED INFORMATION License Amendment Request March 5, 2012 Page E2-6 Criterion I from ER-157P, Rev 8 -Continued operation at the pre-failure power level for a pre-determined time and the decrease in power that must occur following that time are plant-specific and must be acceptably justified.

RESPONSE: Upon loss of an LEFM signal, an existing feedwater ASME Flow Nozzle meter will provide input into the Secondary Calorimetric portion of the Rated Thermal Power (RTP) calculation.

An engineering evaluation was performed to justify an allowed outage time upon loss of the LEFM signal. This evaluation is based on calculation of the drift of a Best Estimate of Reactor Power, a weighted average of the Secondary Calorimetric Power Calculation based upon the feedwater ASME Flow Nozzle meters and the Primary Thermal Power Calculation.

The Secondary Calorimetric Power Calculation is used to determine plant power in the event of a loss of LEFM signal. For purposes of calculating drift of the Secondary Calorimetric parameter, one year of data averaged at 10-minute intervals and reported every 15 minutes was evaluated.

This allows for potential variability from any seasonal effects.Because the LEFM flow meters are not yet operating, Turbine First Stage pressure was used as the reference against which ASME Flow Nozzle drift was calculated.

First Stage pressure was expected to be stable during the short interval, but any variability of the First Stage pressure indication conservatively adds to the bounding results of the drift calculation.

The above analysis demonstrated drift of the Secondary Calorimetric portion of the RTP calculation is insignificant and supports a 72-hour out-of-service period for a non-functional LEFM.The Main Feedwater ASME Flow Nozzles readings on which the Secondary Calorimetric is based will be calibrated to the LEFM output. While functional, the LEFM system corrects and normalizes the ASME Flow Nozzle and the Main Feedwater RTD Temperature signals via correction factors to the more accurate LEFM signals. Use of these correction factors account for all of the uncertainty that exists in the Main Feedwater ASME Flow Nozzle.The above analysis and review of ASME Flow Nozzle fouling and instrumentation calibration history demonstrates that ASME Flow Nozzle fouling/de-fouling related drift, ASME Flow Nozzle instrumentation related drift, and RTP drift over a 72-hour period would be insignificant.

This demonstrates that MNS Unit 1 and 2 operation at or below RTP would be assured over a 72-hour LEFM out-of-service period. It is expected that most issues rendering an LEFM system non-functional could be resolved within a 72-hour out-of-service period.Based upon the above, McGuire will implement a 72-hour Allowed Outage Time (AOT) for a non-functional LEFM system. This is consistent with previous MUR power uprate applications approved by the NRC. A Selected Licensee Commitment (SLC) will be added to require the LEFM to be restored in 72-hours.

If the LEFM is not restored within 72-hours, then within six hours the unit will be reduced to no more than 3411 MWt (the previously licensed rated thermal power).

Enclosure 2

SUMMARY

OF RIS 2002-03 REQUESTED INFORMATION License Amendment Request March 5, 2012 Page E2-7 These requirements ensure that the LEFM inputs are in use whenever power is greater than the pre-uprate RTP level of 3411 MWt and that power will be reduced and maintained at or below the pre-uprate level of 3411 MWt until the LEFM is returned to operable status.Criterion 2 from ER-157P, Rev 8 -A CheckPlus operating with a single failure is not identical to an LEFM Check. Although the effect on hydraulic behavior is expected to be negligible, this must be acceptably quantified if a licensee wishes to operate using the degraded CheckPlus at an increased uncertainty.

RESPONSE: McGuire Nuclear Station will not consider a CheckPlus system with a single failure as a separate category; this will be considered as an inoperable LEFM and the same actions identified in response to Criterion 1 from ER-157P, Rev. 8 above will be implemented.

Criterion 3 from ER-157P, Rev 8 -An applicant with a comparable geometry can reference the above Section 3.2.1 finding to support a conclusion that downstream geometry does not have a significant influence on CheckPlus calibration.

However, CheckPlus test results do not apply to a Check and downstream effects with the use of a CheckPlus with disabled components that make the CheckPlus comparable to a Check must be addressed.

An acceptable method is to conduct applicable Alden Laboratory tests.RESPONSE: As stated in response to Criterion 2 from ER-1 57P, Rev. 8 above, McGuire Nuclear Station will not consider a CheckPlus system with disabled components as a separate category; this will be considered as an inoperable LEFM and the same actions identified in response to Criterion 1 above will be implemented.

Criterion 4 from ER-157P, Rev 8 -An applicant that requests a MUR with the upstream flow straightener configuration discussed in Section 3.2.2 should provide justification for claimed CheckPlus uncertainty that extends the justification provided in Reference 17.(Reference 17 = Letter from Hauser, E (Cameron Measurement Systems), to U.S. Nuclear Regulatory Commission, "Documentation to support the review of ER-157P, Revision 8: Engineering Report ER-790, Revision 1, 'An Evaluation of the Impact of 55 Tube Permutit Flow Conditioners on the Meter Factor of an LEFM CheckPlus, " March 19, 2010) Since the Reference 17 evaluation does not apply to the Check, a comparable evaluation must be accomplished if a Check is to be installed downstream of a tubular flow straightener.

RESPONSE: The ASME feedwater measurement nozzles have a flow straightener immediately upstream.

As discussed in Section 1.1.C above, the ASME feedwater measurement nozzles are located much greater than 4 L/D from the planned location of the LEFMs. The planned location of the LEFMs is also