ML11171A059

Response to Request for Additional Information Regarding the License Amendment Request for Extended Power Uprate Operation - Steam Dryer and Boral Monitoring Program

ML11171A059
Person / Time
Site:	Nine Mile Point
Issue date:	06/13/2011
From:	Philippon M Constellation Energy Group, EDF Group, Nine Mile Point
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC ME1476
Download: ML11171A059 (22)

Text

This letter forwards proprietary information in accordance with 10 CFR 2.390. The balance of this letter may be considered non-proprietary upon removal of Attachments 5 through 7.

P.O. Box 63 CENGM a joint venture of Lycoming, New York 13093 O qn'elt~Energy, %0%eD NINE MILE POINT NUCLEAR STATION June 13, 2011 U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 ATTENTION: Document Control Desk

SUBJECT:

Nine Mile Point Nuclear Station Unit No. 2; Docket No. 50-410 Response to Request for Additional Information Regarding Nine Mile Point Nuclear Station, Unit No. 2 - Re: The License Amendment Request for Extended Power Uprate Operation (TAC No. ME1476) - Steam Dryer and BORAL Monitoring Program

REFERENCES:

(a) Letter from K. J. Poison (NMPNS) to Document Control Desk (NRC), dated May 27, 2009, License Amendment Request (LAR) Pursuant to 10 CFR 50.90:

Extended Power Uprate (b) E-mail from R. Guzman (NRC) to T. H. Darling (NMPNS), dated January 31, 2011, Supplemental Steam Dryer Questions Following 1/13/11 Telecom (c) E-mail from R. Guzman (NRC) to T. H. Darling (NMPNS), dated February 18, 2011, NMP2 EPU LAR - Clarifications on Supplemental Steam Dryer RAIs -

2/15/11 Teleconference (d) E-mail from R. Guzman (NRC) to J. J. Dosa (NMPNS), dated May 12, 2011, NMP2 EPU May 9 RAI Response - Feedback (e) Letter from S. Belcher (NMPNS) to Document Control Desk (NRC) dated December 10, 2010, Response to Request for Additional Information Regarding Nine Mile Point Nuclear Station, Unit No. 2 - Re: The License Amendment Request for Extended Power Uprate Operation (TAC No. ME1476) - Steam Dryer POI This letter forwards proprietary information in accordance with 10 CFR 2.390. The balance of this letter may be considered non-proprietary upon removal of Attachments 5 through 7. ý01c'

Document Control Desk June 13, 2011 Page 2 Nine Mile Point Nuclear Station, LLC (NMPNS) hereby transmits supplemental information in support of a previously submitted request for amendment to Nine Mile Point Unit 2 (NMP2) Renewed Operating License (OL) NPF-69. The request, dated May 27, 2009 (Reference a), proposed an amendment to increase the power level authorized by OL Section 2.C.(1), Maximum Power Level, from 3467 megawatts-thermal (MWt) to 3988 MWt.

By e-mails dated January 31, 2011 and February 18, 2011 (References b and c), the NRC staff requested additional information (RAI) regarding the steam dryer. In addition, in an e-mail dated May 12, 2011 (Reference d), the NRC provided feedback regarding the NMP2 BORAL Monitoring Program that requires an NMPNS response. Attachment 1 (non-proprietary) and Attachment 5 (proprietary) provide the NMPNS response to the RAIs.

To support the response to the RAI issued in the e-mail dated January 31, 2011, NMPNS is providing: 1)

Continuum Dynamics, Inc. (CDI) Report No. 11-03, "Sub-Modeling in the Nine Mile Point Unit 2 Steam Dryer," Revision 1 (Attachment 6 (proprietary)); and 2) CDI Report No. 11-04, "Stress Evaluation of Nine Mile Point Unit 2 Steam Dryer Using ACM Rev. 4.1 Acoustic Loads," Revision 0 (Attachment 3 (non-proprietary) and Attachment 7 (proprietary)).

In addition, Revision 0 of CDI Report No. 11-04, "Stress Evaluation of Nine Mile Point Unit 2 Steam Dryer Using ACM Rev. 4.1 Acoustic Loads," satisfies the following commitment made by NMPNS in a letter dated December 10, 2010 (Reference e):

"Within two months of final resolution of NRC RAIs regarding the steam dryer analysis methodology, NMPNS will submit a revision to CDI Report No. 10-12, Design and Stress Evaluation of Nine Mile Point Unit 2 Steam Dryer Modifications for EPU Operation."

CDI Report No. 11-04 supersedes CDI Report No. 10-12.

Attachments 5 through 7 are considered to contain proprietary information exempt from disclosure pursuant to 10 CFR 2.390. Therefore, on behalf of Continuum Dynamics, Incorporated (CDI), NMPNS hereby makes application to withhold these attachments from public disclosure in accordance with 10 CFR 2.390(b)(i). The affidavit from CDI detailing the reason for the request to withhold the proprietary information is provided in Attachment 4. CDI Report No. 11-03 (Attachment 6) is deemed proprietary in its entirety; thus a non-proprietary version of this attachment has not been provided in accordance with NRC Information Notice 2009-07, Requirements for Submittals, which states: "In instances in which a nonproprietary version would be of no value to the public because of the extent of the proprietary information, the agency does not expect a nonproprietary version to be submitted." defines the new regulatory commitment made in this submittal.

Should you have any questions regarding the information in this submittal, please contact John J. Dosa, Director Licensing, at (315) 349-5219.

Very truly yours,

,9Az1/4;A-7 Michel A. Philippon Manager Operations

Document Control Desk June 13, 2011 Page 3 STATE OF NEW YORK TO WIT:

COUNTY OF OSWEGO I, Michel Philippon, being duly sworn, state that I am Manager Operations - Nine Mile Point, and that I am duly authorized to execute and file this response on behalf of Nine Mile Point Nuclear Station, LLC.

To the best of my knowledge and belief, the statements contained in this document are true and correct.

To the extent that these statements are not based on my personal knowledge, they are based upon information provided by other Nine Mile Point employees and/or consultants. Such information has been reviewed in accordance with company practice and I believe it to be reliable.

Subscribed and sworn before me, a Notary Public in and for the State of New York and County of 0,5 ( t ,this j/'j# day of ,J f,/1_ 2011.

WITNESS my Hand and Notarial Seal:

-7 ,,--tayPub~lic My Commission Expires:

IOWVA L JONES NO"m Publin VwthStat@ ol Now Y~ork Dat/be" " No.oN0.1.

my dt; ,W SB/STD Attachments:

1. Response to Request for Additional Information Regarding License Amendment Request for Extended Power Uprate Operation (Non-Proprietary)

2. List of Regulatory Commitments

3. CDI Report No. 11-04NP, "Stress Evaluation of Nine Mile Point Unit 2 Steam Dryer Using ACM Rev. 4.1 Acoustic Loads," Revision 0 (Non-Proprietary)

4. Affidavit from Continuum Dynamics, Incorporated, Justifying Withholding Proprietary Information

5. Response to Request for Additional Information Regarding License Amendment Request for Extended Power Uprate Operation (Proprietary)

6. CDI Report No.11-03P, "Sub-Modeling in the Nine Mile Point Unit 2 Steam Dryer," Revision 1 (Proprietary)

7. CDI Report No.11-04P, "Stress Evaluation of Nine Mile Point Unit 2 Steam Dryer Using ACM Rev.

4.1 Acoustic Loads," Revision 0 (Proprietary)

Document Control Desk June 13, 2011 Page 4 cc: NRC Regional Administrator, Region I NRC Resident Inspector NRC Project Manager A. L. Peterson, NYSERDA (w/o Attachments 5 through 7)

ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

Certain information, considered proprietary by Continuum Dynamics, Incorporated, has been deleted from this Attachment. The deletions are identified by double square brackets.

Nine Mile Point Nuclear Station, LLC June 13, 2011

ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

By letter dated May 27, 2009, as supplemented on August 28, 2009, December 23, 2009, February 19, 2010, April 16, 2010, May 7, 2010, June 3, 2010, June 30, 2010, July 9, 2010, July 30, 2010, October 8, 2010, October 28, 2010, November 5, 2010, December 10, 2010, December 13, 2010, January 19, 2011, January 31, 2011, February 4, 2011, March 23, 2011, and May 9, 2011, Nine Mile Point Nuclear Station, LLC (NMPNS) submitted for Nuclear Regulatory Commission (NRC) review and approval, a proposed license amendment requesting an increase in the maximum steady-state power level from 3467 megawatts thermal (MWt) to 3988 MWt for Nine Mile Point Unit 2 (NMP2).

By e-mails dated January 31, 2011 and February 18, 2011, the NRC staff requested additional information (RAI) regarding the steam dryer. In addition, in an e-mail dated May 12, 2011, the NRC provided feedback on the NMP2 BORAL Monitoring Program. This attachment provides the NMPNS responses to the RAIs and a revised response to an NRC RAI (Supplemental CSGB-RAI-3.a).

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ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

Draft RAI from E-mail dated January 31. 2011 NMP2-EMCB-SD-RAI-8 S02 (d)

When the originalAcoustic Circuit Model (ACM) method was developed with the aid of the Quad Cities, Unit 2 (QC2) plant data, two sets of data were used to develop and validate the ACM model. The two data sets were taken at 790 MWe and 930 MAVe power levels, corresponding approximately to the original licensed thermalpower (OLTP) and extendedpower uprate (EPU)conditions. One of these data sets was used to develop the model parameters and the other set was used to validate and correct these parameters. As discussed in the CDI Report 07-09, "ACM Revision 4: Methodology to Predict Full Scale Steam Dryer Loads from In-Plant Measurements, with the Inclusion of a Low Frequency Hydrodynamic Contribution," the damping in the main steam lines (MSLs) was increasedby 70 %for the frequency range between 0 and 100 Hz, and only one set of data (data of OL TP) was used to develop the bias and uncertainties of the ACM Revision 4 methodology. In the CDI Report 10-09, "ACM Revision 4.J1: Methodology to Predict Full Scale Steam Dryer Loads from In-Plant Measurements," additional changes were made to develop the A CM Revision 4.1 methodology.

This new version of the ACM includes ((

)). Apparently, these bias and uncertainties are substantially smaller than those associatedwith both the originalA CM method and its 41h revision. In order to ensure that the bias errors and uncertainties of ACM 4.1 are conservative, the licensee (NMPNS) is requested to address the following items:

(a) Validate the ACM Revision 4.1 methodology against the QC2 data obtained at EPU conditions and revise, as warranted,the model parametersofACMRev 4.1, including the bias and uncertainty errors.

(b) Include the ACM version 4.0 data in the reportfor ACM Revision 4.1 (e.g., in Figures 6.1, 6.2, 8.2, and 8.3, and in Table 7.1 of the CDI Report 10-09P, Rev. 2). Also, the licensee is requestedto add a bar chart per Figure RAI-8 SO] (d) in RAI response NMIP2-EMCB-SD-RAI-8 SO] (d) with updated values.

Note that bias errors and uncertaintiesfor ACM version 4.0 should be consistent with those approved previously by the NRC. In other words, the bias and uncertainty errors should be defined over the same frequency ranges that were approved by the NRC and used in A CM version 4.0.

Clarifications to Draft RAI Issued on February 18, 2011 NMP2-EMCB-SD-RAI-8 S02(d): Clarification for Part (a)

Since the safety relief valve (SR V) resonances are not expected at EPU conditionsfor the NMP2 plant, the staff agrees that the ACM 4.1 model may be validated using the Quad Cities Unit 2 data at the power level of 840 Mfe instead of at the 940 MWe power level. However, prior to using the ACM 4.1 modelfor any other plant which may exhibit SRV resonances near EPU, the staff requests that ACM 4.1 be validated over a wider range of Mach numbers, that also include the SR V resonances.

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ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

NMP2-EMCB-SD-RAI-8 S02(d): Clarification for Part (b)

As described in Section 6 of CDI Report 07-09P Rev. 1, the bias and uncertaintyfor ACM Rev. 4.0 was computed over six groups of sensors and then averaged. However, as noted in Section 7 of CDI Report l0-09P, Rev. 3, the bias and uncertaintyfor ACM Rev. 4.1 was computed over a single group of sixteen pressure sensors. The licensee is requested to update the bias error and uncertainty calculationsfor the A CM Rev. 4.1 (Section 7 of CDI Report 10-09P, Rev. 3) to reflect the same procedure used previously to determine the bias errorsand uncertaintiesfor ACM Rev. 4. 0 (Section 6 of CDIReport 07-09P, Rev. 1).

NMPNS Response The NRC issued the draft RAI in an e-mail dated January 31, 2011, and subsequently issued clarifications to the RAI in an e-mail dated February 18, 2011. The NMPNS response is to the clarified RAI.

Response for Part (a)

This response examines the bias and uncertainties for the Quad Cities Unit 2 (QC2) 790 Megawatt-electric (MWe) power level with 16 pressure sensors (as described in Revision 3 of Continuum Dynamics, Inc. (CDI) Report No. 10-09 submitted to the NRC in a letter dated February 4, 2011) and with 6 average sensors, and the QC2 840 MWe power level with 6 average sensors, with all calculations undertaken with Revision 4.1 of CDI's Acoustic Circuit Model (ACM). Model parameter values have not been changed from those previously reported in Revision 3 of CDI Report No. 10-09 for the 790 MWe power level with 16 pressure sensors.

The 16 pressure sensors were located on the outer bank hoods of QC2: P1 to P12 were placed on the outer bank hood facing main steam lines A and B, while P18 to P21 were placed on the outer bank hood facing main steam lines C and D. When the pressure signals are averaged, the main steam line A/B transformed signals are averaged across three vertical positions (P1 to P3, P4 to P6, P7 to P9, and Pl0 to P 12), and the main steam line C/D transformed signals are averaged across two vertical positions (P18 and P20, and P19 and P21).

Bias and uncertainty values computed for the QC2 benchmark at the 790 MWe power level with 16 pressure sensors (from Revision 3 of CDI Report No. 10-09) are shown in Table 1.

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ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

I[

Table 1 - QC2 Benchmark at 790 MWe with 16 Pressure Sensors Bias and uncertainty at the 790 MWe and 840 MWe power levels with 6 average sensors are shown in Table 2.

I((

Table 2 - QC2 Benchmark at 790 MWe and 840 MWe with 6 Average Sensors Total uncertainty for NMP2, including the plant-specific bias and uncertainties, based on the QC2 790 MWe power level with 16 sensors (obtained from Revision 2 of CDI Report No. 10-10 submitted in a letter dated December 10, 2010) and with 6 average sensors, and the QC2 840 MWe power level with 6 average sensors, is shown in Table 3.

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ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

((I Table 3 - NMP2 Total Uncertainty i((

The impact on the NMP2 dryer load can be seen by changing the above percentages into the loading factors to be applied to the ACM prediction, as shown in Figure 1.

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ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

[1 Figure 1 - Loading Factor versus Frequency Interval Response for Part (b)

The averaging of sensors into six groups, and their comparison for bias and uncertainties, and total uncertainty, are given in the response to Part (a). The following table summarizes the minimum stress ratios computed for the three cases examined in response to Part (a):

790 MWe with 790 MWe with 840 MWe with 16 sensors 6 averages 6 averages Minimum Stress Ratio 3.09 3.29 3.47 Table 4 - Minimum Stress Ratios for Various Cases In Table 5, stress ratios at the 17 locations on the NMP2 dryer with the lowest stress ratios at the 790 MWe with 16 sensors are compared with the corresponding stress ratios for the 790 MWe power level with 6 average sensors and the 840 MWe power level with 6 average sensors. The minimum stress ratios are highlighted and appear in Table 4.

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ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY) 790 MNAWe 790 MWe 840 MWe LOCATION Node 16 Sensors 6 Averages 6 Averages

1. Closure Plate/Middle Hood 89317 3.52 3.88 3.67

2. Outer Cover Plate/Outer Hood 95236 3.09 3.40 3.84

3. Hood Support/Outer Cover Plate/Outer 95267 3.13 3.29 3.59 Hood

4. Hood Support/Inner Hood 95644 3.38 3.50 4.15

5. Top Thick Plate/Inner Hood/Top Plate 85512 3.22 3.34 3.93

6. Hood Support/Outer Base Plate/Middle 98067 3.31 3.52 3.76 Backing Bar

7. Thick Vane Bank Plate/Thin Vane Bank 90170 3.42 3.67 3.47 Plate/Side and Plate/Side Plate Ext/End Plate

8. Hood Support/Inner Hood 99540 3.17 3.29 3.87

9. Hood Support/Inner Hood 95638 3.51 3.64 4.33

10. Side Plate/Top Plate 93031 3.64 4.10 4.17

11. Closure Plate/Inner Hood 95975 4.00 4.34 4.20

12. Entry Bottom Perf/Side Plate/End Plate 91154 3.52 3.81 3.68

13. Top Thick Plate/Side Plate/Closure Plate 96096 4.09 4.45 4.28

14. Side Plate/Brace 89646 4.22 4.51 4.33

15. Hood Support/Inner Hood 90430 3.65 3.79 4.48

16. Hood Support/Middle Hood 96037 3.78 4.13 4.53

17. Outer Cover Plate/Man Way Overlap 87488 3.76 4.26 4.66 Table 5 - Stress Ratios for Various Cases Revision 3 of CDI Report No. 10-09 and Revision 2 of CDI Report No. 10-10 (submitted in letters dated February 4, 2011 and December 10, 2010, respectively) were developed with 16 sensors. These results are compared with 6 average sensors in Table 4. The 6 average sensors were established consistent with the methodology previously approved by the NRC in the Hope Creek and Vermont Yankee Extended Power Uprates.

In this RAI, the NRC requested that the six average sensor results be shown, with summary stress results provided in Table 4 and detailed results provided in Table 5. ((

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ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

Additional Request for Information In a teleconference between the NRC and NMPNS held on April 21, 2011, the NRC requested that NMPNS explain why the bias computed with 16 pressure sensors is not the same as the bias computed with 6 average sensors. The explanation follows.

The bias formula may be written (from Revision 2 of CDI Report No. 10-10 submitted in a letter dated December 10, 2010) as:

BIAS= RMSmeaed- 3 . RMS. ,d -1

, RMSped.d 3 R Sp-diS d where it may be seen that if the predictions are, on average, larger than the measured data, the bias will be negative.

[R 8 of 15

ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

NMP2-EMCB-SD-RAI 21 S02 In response to NMP2-EMCB-SD-RAI 21 S01, the licensee describes the generic submodeling procedure followedfor the stress analysis of the NMP2 steam dryer. The licensee provides a detailed description of its applicationto the modified closure plate to illustrate its use. The staff has several questions regarding this procedureand requestsfollowing information to address these questions, as provided below.

a. Does any submodeling for determining the stresses at a structural discontinuity include another structuraldiscontinuity near its cut boundary?

b. For each submodel, provide a comparison of stresses (including stress distribution and maximum stress) at the structuraldiscontinuityfrom the global analysis andfrom the submodeling prior to any mesh refinement. Please discuss how this difference in the stresses at the discontinuity is addressed in the submodel stress analysis?

c. What is the error associated with the assumption of the linear distribution of damping and inertia forces?

d Provide the results showing convergence of the stresses at the structuraldiscontinuity as the mesh is refined. For each submodel, please discuss what the bias error is associated with the mesh refinement.

e. To avoid significant computational efforts, the licensee uses the global stress analysis results to identify the pair of time indices, i andj, which maximizes the alternatingstress intensity, Sj. Then, the licensee performs a static analysis of the submodel at these two times. However, these two times (pairi andj) may not correspondto the pair of time indices, k and 1, that would maximize Sk, based on the full dynamic analysis of the submodel. Please discuss any potential errors introduced by this use of global stress analysis results.

f Please address any potential total bias and uncertainty errors associatedwith the use of submodeling for estimating the stresses at the structuraldiscontinuity.

g. In the stress tables of the final stress analysis report,please list the stress reductionfactors resulting from the submodeling analysis. Also, please identify the weld modifications that are included in the final analysis.

NMPNS Response 9 of 15

ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY) 10 of 15

ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

))

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ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

Conclusions CDI Report No. 11-04 (Attachments 3 and 7) provides the final ACM 4.1 based NMP2 steam dryer stress evaluation. It determined that the NMP2 steam dryer meets the NRC staff recommended minimum alternating stress ratio of 2.0 for EPU conditions with the implementation of the following modifications:

1. Reinforcement strips are added to the closure plates.

2. Reinforcements to the upper-most and middle lifting rod braces are made in the form of additional strengthening plates.

3. Increase the attachment weld size of the lower-most lifting rod brace from '/4" to 1/2".

4. A 1/8" curved plate is placed over the middle hood section lying outboard of the closure plate.

5. Four 15 lb masses are added to the central inner hood panels.

6. Stress relief cut-outs are added to the outer hood/hood support/base plate junctions to alleviate local stresses.

7. Four 10 lb masses are added to the central middle hood panels.

These modifications are discussed in detail in Section 5 of CDI Report No. 11-04 (Attachments 3 and 7).

Note: CDI Report No. 11-04 (Attachments 3 and 7) also evaluated the addition of a wrap-around weld to the bottom of the drain channel/skirt weld. This modification is not required to meet the recommended minimum alternating stress ratio of 2.0 for EPU conditions. Therefore, it will not be installed.

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ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

Additionally, CDI Report No. 11-04 (Attachments 3 and 7) concludes that only ((

)) are required to demonstrate that the stream dryer meets the NRC staff recommended minimum alternating stress ratio of 2.0 for EPU conditions. These (( )) are required to demonstrate that modifications 2 and 6 listed above meet the recommended minimum alternating stress ratio of 2.0. CDI Report No. 11-03 (Attachment 6) contains additional sub-models using the ((

)) that demonstrate substantial margin above the recommended minimum alternating stress ratio of 2.0 for several other steam dryer locations.

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ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY)

RAI#1 from NRC E-mail dated April 14, 2011 Supplemental CSGB-RAI-3.a On page 6 of Attachment 1 of its letter dated March 23, 2011, the licensee states that, "NMPNS does not intend to utilize these coupons [for the initial 10 [BORAL(RJ spent fiel racks] since the coupon tree was not installed at the same time as the associated racks. " The NRC staff is uncertain whether the

[BORAL¶.] material installed in 2001 has an effective surveillance monitoringprogram. Please provide the surveillance approachand testingfor these 10 [BORAL'ý] spentfuel racks.

Original NMPNS Response As stated in the letter dated March 23, 2011, a coupon tree representative of the spent fuel racks installed in 2001 was installed in the NMP2 spent fuel pool in 2007. Following a telecom with the NRC on April 19, 2011, that clarified this RAI, NMPNS revised the NMP2 [BORAL] Monitoring Program to include a plan to test and inspect coupons from the coupon tree representative of the spent fuel racks installed in 2001.

The NMP2 [BORAL] Monitoring Program now requires a coupon from the coupon tree representative of the spent fuel racks installed in 2001 and a coupon from one of the coupon trees representative of the spent fuel racks installed in 2007 to be removed in 2012. Following this, a coupon from the coupon tree representative of the spent fuel racks installed in 2001 and a coupon from one of the coupon trees representative of the spent fuel racks installed in 2007 will be removed on a ten-year frequency.

The coupons from the coupon trees will be tested and inspected in accordance with the methodology and acceptance criteria defined in the letter dated March 23, 2011.

Revised NMPNS Response In an e-mail dated May 12, 2011, the NRC provided the following feedback regarding the response to CSGB-RAI-3.a:

Specifically, after review of the response to RAI-3. a, the staff understands that NMPNS would like to use the inspection and testing of coupons installed in 2007 to monitor [BORAL'j] spent fuel racks installed in 2001. However, the staff does not think that using coupons (installed 6 years after the

[BORAL'1¶/ material it's supposed to monitor) is an appropriate surveillance monitoring approach/programbecause the racks have had more exposure to spent fuel pool conditions than the coupons. The NMPNS response appears to be inconsistent with what the staff understood was the licensee's intended approachfor answering the question (when presented in the previous phone call).

If a new analysis has been performed to justify using the 2007 coupons to represent the 2001

[BORAL'P], the staff requests the licensee to provide it as additionalexplanation to support the RAI-

3. a supplemental response.

On May, 18, 2011, NMPNS and the NRC discussed the NMP2 monitoring program regarding the BORAL spent fuel racks, and the NRC feedback provided in an e-mail dated May 12, 2011. NMPNS understands that the coupon tree installed in 2007, comprised of the same lot of material as our Phase 1 BORAL spent fuel racks installed at NMP2 in 2001, does not have as much exposure to the NMP2 spent 14 of 15

ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE OPERATION (NON-PROPRIETARY) fuel pool conditions as the spent fuel racks installed in 2001. As such, NMPNS will conduct in-situ Boron-10 Areal Density Gauge for Evaluating Racks (BADGER) testing on the Phase 1 BORAL spent fuel racks installed at NMP2 in 2001 on a 10-year frequency, beginning in 2012. The BADGER testing program will be the surveillance program for the Phase 1 BORAL spent fuel racks installed at NMP2 in 2001.

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ATTACHMENT 2 LIST OF REGULATORY COMMITMENTS Nine Mile Point Nuclear Station, LLC June 13, 2011

ATTACHMENT 2 LIST OF REGULATORY COMMITMENTS The following table identifies the action committed to in this document by Nine Mile Point Nuclear Station, LLC. Any other statements in this submittal are provided for information purposes and are not considered to be regulatory commitments.

Direct questions regarding this commitment to John J. Dosa, Director Licensing, at (315) 349-5219.

REGULATORY COMMITMENT DUE DATE NMPNS will conduct in-situ Boron-10 Areal Density Gauge for Evaluating Racks 10-year (BADGER) testing on the Phase 1 BORAL Racks installed at NMP2 in 2001 on a 10 frequency, year frequency, beginning in 2012. The BADGER testing program will be the beginning in surveillance program for the Phase 1 BORALRacks installed at NMP2 in 2001. 2012 I of I