LR-N08-0028, Responses to Requests for Additional Information Request for License Amendment - Extended Power Uprate

Responses to Requests for Additional Information Request for License Amendment - Extended Power Uprate

ML080360467
Person / Time
Site:	Hope Creek
Issue date:	01/25/2008
From:	Barnes G Public Service Enterprise Group
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LCR H05-01, Rev 1, LR-N08-0028
Download: ML080360467 (26)

Text

PSEG Nuclear LLC P.O. Box 236, Hancocks Bridge, New Jersey 08038-0236 0PSEG Nuclear LLC 10 CFR 50.90 LR-N08-0028 LCR H05-01, Rev'. 1 January 25, 2008 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington-, DC 20555-0001 Hope Creek Generating Station Facility Operating License No. NPF-57 NRC Docket No. 50-354

Subject:

Responses to Requests for Additional Information Request for License Amendment - Extended Power Uprate

Reference:

1) Letter from George P. Barnes (PSEG Nuclear LLC) to USNRC, September 18, 2006

2) Letterfrom USNRC to William Levis (PSEG Nuclear LLC),

January 23, 2008

3) Letter from USNRC to William Levis (PSEG Nuclear LLC),

January 25, .2008 In Reference 1, PSEG Nuclear LLC (PSEG) requested an amendment to Facility Operating License NPF-57 and the Technical Specifications (TS) for the ýHope Creek Generating Station (HCGS) to increase the maximum authorized power level to 3840 megawatts thermal (MWt).

In Reference 2, the NRC requested additional information concerning PSEG's request. to this letter provides. PSEG's responses. Attachment 1 also provides responses to two additional questions, in Reference 3.

As discussed in the response to RAI 14.66 2nd Follow-Up - 1,PSEG will provide an evaluation of the differences and resulting changes (if any) to the finite element model bias and uncertainty by February 08, 2008. contains information proprietar~y to Continuum Dynamics, Inc. (C.D.l.).

C.DI. requests that the proprietary informhation in Attachment 1 be withheld from public 95-2168 REV. 7/99

LR-N08-0028 LCR H05-01, Rev. 1 January 18, 2008 Page 2 disclosure in accordance with 10 CFR 2.390(a)(4). An affidavit supporting this request is included with Attachment 1. A non-proprietary version of PSEG's Attachment 1

.responses is provided in Attachment 2.

There are no regulatory commitments contained within this letter.

Should you have any questions regarding this submittal, please contact Mr. Paul Duke at 856-339-1466.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on /129 (date)c~

Sincerely, George P. Barnes Site Vice President Hope Creek Generating Station

LR-N08-0028 LCR H05-01, Rev. 1 January 25, 2008 Page 3 Attachments (2)

1. Response to Request for Additional Information (proprietary)

2. Response to Request for Additional Information (non-proprietary) cc: S. Collins, Regional Administrator - NRC Region I J. Lamb, Project Manager - USNRC NRC Senior Resident Inspector - Hope Creek P. Mulligan, Manager IV, NJBNE

4rA:W Continuum Dynamics, Inc.

(609) 538&0444 (609) 53&-0464 fax 34 Lexington Avenue Ewing, NJ 086 18-2302 AFFIAVIT Re: Responses to Hope Creek Generating Station - Request for Additional Information Regarding Extended Power Uprate (TAO No. MD3 002),

January 23, 2008 1, Barbara A. Agans, being duly sworn, depose and state as follows:

I I hold the position of Director, Business Administration of Continuum Dynamics, Inc. (hereinafter referred to as C.D.I.), and I am authorized to make the request for withholding from Public Record the Information contained in the documents described in Paragraph 2. This Affidavit is submiited to the Nuclear Regulatory Commission (NRC) pursuant to 10 CER 2.390(a)(4) based on the fact that the attached information consists of trade secret(s) of C.D.I. and that the NRC will receive the information from C.D.1. under privilege and in confidence.

2.- The Information sought to be withheld, as transmitted to PSEG Nuclear LLC as attachment to C.D.I. Letter No. 080 17 dated 25 January.2008 Responses -to Hope Creek Generating Station - Request for Additional Information Regarding Extended Power Uprate (ITAC No. MDii 3002), January 23, 2008.

3. The Inormation summarizes:

(a) a process or method, including supporting data and analysis, where prevention of its use by C.D.L.'s competitors without license from C.D.I. constitutes a competitive advantage over other companies; (b) Information which, if used by a competitor, would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing of a similar product; (c) Information which discloses patentable subject matter for which it may be desirable to obtain patent protection.

The information sought to be withheld is considered to be proprietary for the reasons set forth in paragraphs 3(a), 3(b) and 3(c) above.

4. The Information has been held in confidence by C.D.L., its owner. The Information has consistently been held in confidence by C.D.I. and no public disclosure has been made and it is not available to the public. All disclosures to

third parties, which have been limited, have been made pursuant to the terms and conditions contained in C.D.T. 's Nondisclosure Secrecy Agreement which must be fulfly executed prior to disclosure.

.5. The Information is a type customarily held in confidence by C.D.T. and there is a rational basis therefore. The Information is a type, which C.D.T. considers trade secret and is held in confidence by C.D.T. because it constitutes a source of competitive advantage in the competition and performance of such work in the industry. Public disclosure of the Information is likely to cause substantial harm to C.D.T.'s competitive position and foreclose or reduce the availability of profit-making opportunities.

I declare under penalty of perjury that the foregoing affidavit and the matters stated therein are true and correct to be the best of my knowledge, information and belief.

Executed on this ____ day of .. ) L 2008.

brara A. Agans Continuum Dynamics, Inc.

Subscribed and sworn before me this day: 9c?

C4fýurese4 ýbc EILEEN P. BURMEISTER NOTARY PUBLIC OF NEW JERSEY MY COMM. EXPIRES MAY 6,2012

LR-N08-0028 ATTACHMENT 2 Hope Creek Generating Station Facility Operating License NPF-57 Docket No. 50-354 Extended Power Uprate Response to Request for Additional Information In Reference 1, PSEG Nuclear LLC (PSEG) requested an amendment to Facility Operating License NPF-57 and the Technical Specifications (TS) -for the Hope Creek Generating Station (HCGS) to increase the maximum authorized power level to 3840 megawatts thermal (MWt).

In References 2 and 3, the NRC requested additional information concerning PSEG's request. PSEG's responses are provided below.

RAI 14.66 2nd Follow-Up -I Page .22 of Continuum Dynamics, Inc. (CDI) Report 07-27P, "Finite Element Modeling Bias and Uncertainty Estimates Derived from the Hope Creek Unit 2 Dryer Shaker Test, Rev. 0," presents damping values computed for the finite element (FE) model to best match FE and measured acceleration response function peaks. CDI states that the inferred FE damping values are consistent with measured damping values in STI Technologies Report PA2168, "Hope Creek Steam Dryer Vibration Test." However, no damping values (other than those for low frequency rigid body modes) are presented in the STI report.

(a) Provide and plot the damping values from the measurements as a function of shaker location and frequency. Also include minimum, maximum, mean,-and root mean square values (computed over frequency) for each shaker location consistent with those in Table 3 in CDI Report 07-27P.

Response

Data Description A 24 channel dynamic signal analyzer was used to acquire and process the signals from the sensors. ICP signal conditioning in the analyzer allows direct connection of the sensors. The signals were digitized using 24 bit resolution and a sampling rate of 625Hz. During the steam dryer test, the sine sweep method was used to identify the most prominent natural frequencies excited from each driving point. The sweep tests were not designed to extract structural damping, values. Frequency functions were calculated for each signal using 16384 lines to achieve a frequency resolution 0.019 Hz in the frequency band up to 250 Hz. A Hanning window was used to

LR-NO8-0028 Attachment 2 Page 2 mitigate leakage in the Fourier transform. The use of an exponential weighting window is known to bias damping estimates high (Formenti & McMillan, S&V Questions & Answers, Sound and Vibration Magazine, p.2, 1999)'. The affect of a Hanning window is likely to bias damping estimates high as well, but the exact magnitude is not known. Modal damping ratios wer6eextracted using-the LMS PolyMax modal parameter estimator.

Damping Estimates Table 1 below summarizes the experimental damping estimates. The graphs on the following pages show the analytic and experimental damping estimates as functions of frequency by driving point (shaker location).

(b)Plot and compare the measured damping values andý FIE damping, values inferred in CDI Report No.07-27P as a function of frequency and shaker location.

Response

The requested information is contained in Figures 1through 8 below.

LR-N08-0028 Attachment 2 Page 3 Figure 1 Driving point 1 experimental damping ratios 11 11

LR-N08-0028 Attachment 2 Page 4 Figure 2 Driving point 2 experimental damping ratios 11

LR-N08-0028 Attachment 2 Page 5 Figure 3 Driving point 3 experimental damping ratios 11

LR-N08-0028 Attachment 2 Page 6 Figure 4 Driving point 4 experimental damping ratios 11

LR-N08-0028 Attachment 2 Page 7 Figure 5 Driving point 5 experimental damping ratios III 11

LR-N08-0028 Attachment 2 Page 8 Figure 6 Driving point 6 experimental damping ratios 11

LR-N08-0028 Attachment 2 Page 9 Figure 7 Driving point 7 experimental damping ratios 11

LR-N08-0028 Attachment 2 Page 10 Figure 8 Driving point 8 experimental damping ratios 11l 11

LR-N08-0028 Attachment 2 Page 11 (c) Reconcile the differences between the measured and inferred FE damping values, and provide, the resulting FE bias and uncertainty.

Response

The tables of measured and inferred FE damping values show that the ranges of values are consistent with each other. PSEG will provide an evaluation of the differences and resulting changes (if any) to the FE bias and uncertainty by

'February 08, 2008.

RAI 14.66 2nd Follow-Up - 11 STI Technologies Report PA2168, "Hope Creek Steam Dryer Vibration Test" states on page 7 that a Hanning window was applied to the measured vibration response.

Hanning windows reduce peak amplitudes in Fourier Transforms. Was the Hanning window used during the peak response measurements conducted by driving -the shaker at a single frequency? If so, how has the peak amplitude reduction been accounted for?

Response

The Hanning window was applied to both the excitation and response during the sine dwell test. Therefore the same amplitude reduction is applied to both the applied force and to the measured acceleration. For a linear model such as the one developed by CDI, reducing the excitation and response by the same factor does not change the predicted -frequency response function.

RAI 14.79 - 3 rd Follow-up In RAI 14.79 - 2 nd Follow-up, PSEG was asked to evaluate the effects of the 10% non-conservative bias error in its FE stress calculations on the stress margins. In LR-N08-0006 dated 15 January-2008, PSEG argues that the stress underprediction bias factor associated with the dryer FE models may be neglected since it is embedded within the uncertainty associated with the FE models based on dryer shaker tests of accelerations.

However, the stresses converge with mesh resolution more slowly than displacements and accelerations do (accelerations were measured and compared in the dryer shaker test study), and that stress bias errors cannot be replaced with displacement-based uncertainties. When.PSEG submits its final dryer stress analyses, it should include the 10% non-conservative bias error associated with stress convergence in the margin calculations for maximum and alternating stress intensities.

Response

,LR-N08-0028 Attachment 2 Page 12 Note that both e,, and efe were calculated on grids with mesh resolution comparable to that used in operational steam dryer analysis.

The NRC staff subsequently pointed out that peak finite element stresses do not converge at the same rate as displacements. In a finite element calculation, the displacement generally converges at a different rate than stress since the latter is essentially a spatial derivative of the former. [

LR-NOB-0028 Attachment 2 Page 13

'I]

Figure 1. Displacement amplitude vs. frequency for location 2 in the 100-102 Hz frequency range.

-LR-N08-0028 Attachment 2 Page 14 As was also observed in the corresponding stress amplitude the displacement exhibits a peak about frequency 100.75 Hz. The associated peak values are plotted versus normalized mesh size squared in Figure 2. [

With this result in hand, one can conclude that the total error in the stress prediction due to both finite element modeling approximations and finite mesh size is:

LR-N08-0028 Attachment 2

.Page 15 Figure 2. Extrapolation of the peak displacement amplitudes as a function of mesh size. The peak displacement amplitudes occur about 100.75 Hz in Figure 1.. 'The mesh size is normalized by the mesh spacing on Mesh xl.

PSEG's final dryer stress analyses will include the additional (( ,)) error in the margin calculations for maximum and alternating stress intensities.

LR-N08-0028 Attachment 2 Page 16 RAI 14.120(f) - 2 nd Follow-up PSEG clearly explains [

))So that the staff may quantitatively determine the degree to which the Main Steam Line inputs have been filtered (using equation 8 on page 83 of the report),

provide plots of the frequency-dependent MSL input loads before and after filtering using the low-flow data.

Response

Figures 14.120.1 to 14.120.4 plot the PSID of the MSL ýinlet pressures as a function of frequency. [

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LR-N08-0028 Attachment 2 Page 21 References

1) Letter from George P. Barnes (PSEG Nuclear LLC) to USNRC, September 18,

.2006

2) Letter from USNRC to William Levis .(PSEG Nuclear LLC), January 23, 2008

3) Letter from USNRC to William Levis (PSEG Nuclear LLC), January 25, 2008