LR-N08-0257, Clarification to Final Safety Evaluation for Extended Power Uprate, License Amendment No. 174

Clarification to Final Safety Evaluation for Extended Power Uprate, License Amendment No. 174

ML083370304
Person / Time
Site:	Hope Creek
Issue date:	11/21/2008
From:	Keenan J Public Service Enterprise Group
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LR-N08-0257
Download: ML083370304 (5)

Text

PSEG Nuclear LLC P.O. Box 236,, Hancocks Bridge, NJ 08038-0236 0 PSEG NuclearL.L. C.

LR-N08-0257 November 21, 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:

Clarification to Final Safety Evaluation for Extended Power Uprate, License Amendment No. 174

Reference:

1) Letter from Christine T. Neely (PSEG Nuclear LLC) to USNRC, September 24, 2008 On May 14, 2008, the NRC issued Amendment No. 174 to the operating license for the Hope Creek Generating Station (HCGS), increasing the authorized maximum power level by approximately 15 percent, from 3,339 megawatts thermal (MWt) to 3,840 MWt.

In Reference 1, PSEG Nuclear (LLC) identified some items requiring clarification in the related safety evaluation.

Attachment I to this letter provides an additional clarification to the safety evaluation. A markup of the affected page of the safety evaluation is provided in Attachment 2. The clarification does not invalidate the conclusions documented in the safety evaluation.

There are no regulatory commitments in this letter or attachments.

If you have any questions or require additional information, please contact Mr. Paul Duke at 856-339-1466.

Sincerely, 4JeeKeenan Manager - Licensing PSEG Nuclear LLC

LR-N08-0257 November 21, 2008 Page 2 Attachments (2)

1. Clarification to Final Safety Evaluation for Extended Power Uprate, License Amendment No. 174

2. Marked-up Page cc: S. Collins, Regional Administrator - NRC Region I J. Lamb, Project Manager - USNRC NRC Senior Resident Inspector - Hope Creek P. Mulligan, Manager IV, NJBNE

LR-N08-0257 Page 1 of 1 ATTACHMENT 1 Hope Creek Generating Station NRC Docket No. 50-354 Clarifications to Final Safety Evaluation for Extended Power Uprate, License Amendment No. 174 Item Location Existing Text Recommended Text Basis

1. Section A.2.1, Steam PSEG did not take credit for [delete] The stress results account for all Dryer, Acoustic Circuit conservative (negative) bias the end-to-end biases and Model values in the stress results. uncertainties in the loads model.

Treatment of Acoustic Circuit Page A-5 Model biases and uncertainties is described in:

• Section 2, C.D.I.

Technical Note No.07-29P, Rev. 0 (Attachment 6 to PSEG letter LR-N07-0171, August 3, 2007)

• Table 11, C.D.I. Report No.07-17P, Rev. 4 (Attachment 3 to PSEG letter LR-N08-0033, January 30, 2008)

"Page numbers correspond to Appendix A to the Final Safety Evaluation for Amendment No. 174, Accession No. ML081230648

LR-N08-0205 ATTACHMENT 2 Hope Creek Generating Station NRC Docket No. 50-354 Clarifications to Final Safety Evaluation for Extended Power Uprate, License Amendment No. 174 Marked-up Pages Page A-5

A-5 Acoustic Circuit Model PSEG developed a new acoustic circuit model (ACM Rev. 4) to predict full scale steam dryer loads from in-plant measurements, with the inclusion of a low frequency hydrodynamic contribution. The model is described in LR-N07-0171, 9 Attachment 3, CDI Report 07-09P (Rev.

1), "Methodology to Predict Full Scale Steam Dryer Loads from In-Plant Measurements, with the Inclusion of a Low Frequency Hydrodynamic Contribution" (Proprietary), 10 and is based on the Bounding Pressure Model defined in LR-N06-0286,1 1 Attachment 20, CDI Report 05-28P, "Bounding Methodology to Predict Full Scale Steam Dryer Loads from In-Plant Measurements (C.D.I. Proprietary)."1 2 The new model improves the prediction of the steam dryer loads at low frequencies up to 60 Hz. ((

))

The parameters of the new ACM Rev. 4 are "tuned" by means of QC2 in-plant measurements at OLTP (790 megawatts electric [MWe]) because the corresponding Mach number (M=O.105) in QC2 MSLs would be similar to that for Hope Creek at EPU conditions. The MSL strain gage measurements are used to estimate the ((

)). The predictions of the new version are compared with the pressure measurements on the steam dryer in QC2. The low frequency (<

60 Hz) prediction appears to envelop the QC2 measurements at low frequencies. In addition, the new model seems to reduce the bias and uncertainty errors in the frequency range of 40 to 60 Hz (bias from 14 to 0.4 percent and uncertainty from 15 to 7 percent).

In LR-N07-0171, Attachment 3, CDI Report 07-09P (Rev. 1), "Methodology to Predict Full Scale Steam Dryer Loads from In-Plant Measurements, with the Inclusion of a Low Frequency Hydrodynamic Contribution," PSEG compared the direct measurements and 'blind' simulations of the surface pressures on the QC2 dryer (prior to the installation of acoustic side branches (ASBs) at QC) and established the bias errors and uncertainties associated with ACM-generated loads on the dryer. The bias errors and uncertainties of the analysis were found to be frequency-dependent. For example, the bias errors were negative (conservative), or less than (()) percent, for all evaluated frequency ranges with the exception of a positive [ ]

percent bias error between 116 and 120 Hz. The uncertainty values lu p rcent wilt i ic intervals over th nc range. Pno ake redi o ons aiv e ive value nthe ress Sul . he largebia e r"7 )) percent) requencie n1 a is ase n e ACM's underestimation of the dryer loads caused by flow-induced acoustic resonances in the SRVs of the QC2 plant at 156 Hz.

Because similar errors may occur for other SRV resonances in other plants, PSEG will apply the

(( )) percent bias and (( )) percent uncertainty to any SRV resonance that may appear in the MSL signals during Hope Creek power ascension.

9 PSEG Letter (LR-N07-0171) to NRC dated August 3. 2007, "Response to Request for Additional Information, Request For Ucense Amendment, Extended Power Uprate" ADAMS Accession No. ML072250369 10CDI Report 07-09P (Rev. 1). "Methodology to Predict Full Scale Steam Dryer Loads from In-Plant Measurements, with the Inclusion of a Low Frequency Hydrodynamic Contribution" (Proprietary) ADAMS Accession No. ML072250371 11PSEG Letter (LR-N06-0286) to NRC dated September 18, 2006, "Request for License Amendment Extended Power Uprate,

~ Hope Creek Generating Station Facility, Operating License NPF-57, Docket No. 50-354" ADAMS Accession No. ML062680451 12 ADAMS Accession No. ML061300484 (Proprietary)