ML063250092

Extended Power Uprate Acceptance Review

ML063250092
Person / Time
Site:	Susquehanna
Issue date:	11/21/2006
From:	John Lubinski Plant Licensing Branch III-2
To:	Mckinney B Susquehanna
Guzman R, NRR/DORL, 415-1030
References
TAC MD3309, TAC MD3310
Download: ML063250092 (6)

Text

November 21, 2006 Mr. Britt T. McKinney Sr. Vice President and Chief Nuclear Officer PPL Susquehanna, LLC 769 Salem Blvd., NUCSB3 Berwick, PA 18603-0467

SUBJECT:

SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1 AND 2 - EXTENDED POWER UPRATE (EPU) ACCEPTANCE REVIEW (TAC NOS. MD3309 AND MD3310)

Dear Mr. McKinney:

By letter dated October 11, 2006 (Agencywide Documents Access and Management System Accession No. ML043270480), PPL Susquehanna, LLC (PPL, the licensee), submitted its request to amend the operating license for Susquehanna Steam Electric Station, Units 1 and 2 (SSES 1 and 2) to increase the maximum authorized power level from 3489 megawatts thermal (MWt) to 3952 MWt, an increase of approximately 13 percent in thermal power.

The purpose of this letter is to provide the results of the Nuclear Regulatory Commission (NRC) staff's acceptance review of the EPU application for SSES 1 and 2. The acceptance review determines whether or not there is sufficient detail to allow the NRC staff to proceed with its detailed technical review. The review also ensures that the application adequately characterizes the regulatory requirements and licensing basis of the plant.

The NRC staff has reviewed your application and has determined that it does not include sufficient information to allow the NRC staff to proceed with a detailed technical review.

Specifically, it does not provide completed analyses to evaluate the capability of the steam dryers to maintain their structural integrity at the proposed EPU conditions. In addition, the application does not provide technical information in sufficient detail to enable the NRC staff to make an assessment regarding the reliability of the proposed analysis or methodology, and the acceptability of the proposed amendment. Specific areas which require additional information to be submitted are included in the enclosure to this letter.

During a conference call on November 17, 2006, your staff stated it would provide the additional information to address the concerns contained in the enclosure by December 5, 2006. Upon receipt of the supplemental information, the NRC staff will review the information as part of its acceptance review, and determine whether the enclosed comments are adequately addressed.

If the response is not provided by December 5, 2006, or does not adequately address the concerns, the NRC staff may proceed on your request consistent with 10 CFR 2.108, Denial of application, for failure to supply information.

B. McKinney If you have any questions, please contact Mr. Richard V. Guzman, at (301) 415-1030.

Sincerely,

/RA/

John W. Lubinski, Deputy Director Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-387 and 50-388

Enclosure:

As stated cc w/encl: See next page

ML063250092 OFFICE LPLI-1/PM LPLI-1/LA EEMA/BC LPLI-1/BC DORL/DD NAME RGuzman SLittle KManoly RLaufer JLubinski DATE 11/21/06 11/21/06 11/21/06 11/21/06 11/21/06

Susquehanna Steam Electric Station, Units 1 and 2 cc:

Robert A. Saccone Vice President - Nuclear Operations PPL Susquehanna, LLC 769 Salem Blvd., NUCSB3 Berwick, PA 18603-0467 Terry L. Harpster General Manager - Plant Support PPL Susquehanna, LLC 769 Salem Blvd., NUCSA4 Berwick, PA 18603-0467 Rocco R. Sgarro Manager - Nuclear Regulatory Affairs PPL Susquehanna, LLC Two North Ninth Street, GENPL4 Allentown, PA 18101-1179 Walter E. Morrissey Supervising Engineer Nuclear Regulatory Affairs PPL Susquehanna, LLC 769 Salem Blvd., NUCSA4 Berwick, PA 18603-0467 Michael H. Crowthers Supervising Engineer Nuclear Regulatory Affairs PPL Susquehanna, LLC Two North Ninth Street, GENPL4 Allentown, PA 18101-1179 Steven M. Cook Manager - Quality Assurance PPL Susquehanna, LLC 769 Salem Blvd., NUCSB2 Berwick, PA 18603-0467 Luis A. Ramos Community Relations Manager, Susquehanna PPL Susquehanna, LLC 634 Salem Blvd., SSO Berwick, PA 18603-0467 Bryan A. Snapp, Esq Assoc. General Counsel PPL Services Corporation Two North Ninth Street, GENTW3 Allentown, PA 18101-1179 Supervisor - Document Control Services PPL Susquehanna, LLC Two North Ninth Street, GENPL4 Allentown, PA 18101-1179 Richard W. Osborne Allegheny Electric Cooperative, Inc.

212 Locust Street P.O. Box 1266 Harrisburg, PA 17108-1266 Director, Bureau of Radiation Protection Pennsylvania Department of Environmental Protection Rachel Carson State Office Building P.O. Box 8469 Harrisburg, PA 17105-8469 Senior Resident Inspector U.S. Nuclear Regulatory Commission P.O. Box 35, NUCSA4 Berwick, PA 18603-0035 Regional Administrator, Region 1 U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Board of Supervisors Salem Township P.O. Box 405 Berwick, PA 18603-0035 Dr. Judith Johnsrud National Energy Committee Sierra Club 443 Orlando Avenue State College, PA 16803

Enclosure SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1 AND 2 (SSES 1 AND 2)

EXTENDED POWER UPRATE (EPU) APPLICATION NRC STAFF ACCEPTANCE REVIEW COMMENTS PPL SUSQUEHANNA, LLC DOCKET NOS. 50-387 AND 50-388 By letter to the Nuclear Regulatory Commission (NRC) dated October 11, 2006, PPL Susquehanna, LLC (PPL, the licensee) submitted a request to amend the operating license for Susquehanna Steam Electric Station, Units 1 and 2 (SSES 1 and 2) to increase the maximum authorized power level from 3489 megawatts thermal (MWt) to 3952 MWt, an increase of approximately 13 percent in thermal power. In accordance with its procedures for reviewing EPU applications, the NRC staff performed an acceptance review of PPLs EPU application to determine whether it was sufficient to allow the staff to proceed with its detailed technical review.

The NRC staff has reviewed your application and has determined that it does not provide completed analyses to evaluate the capability of the steam dryers to maintain their structural integrity at the proposed EPU conditions. In addition, the application does not provide technical information in sufficient detail to enable the NRC staff to make an assessment regarding the reliability of the proposed analysis or methodology, and the acceptability of the proposed amendment. Specifically, the NRC staff has identified the following deficiencies which have not been adequately addressed in PPLs application for the NRC staff to proceed with its technical review:

1.

Operating experience shows that previous applications of an acoustic circuit analyses have determined pressure loads on steam dryers based on pressure fluctuation measurements in the main steam lines caused by downstream sources in the steam lines. The licensee indicates in Attachment 10, Section 4.2.5.1 of their submittal, that the pressure pulses measured in the main steam line are generated by hydrodynamic sources. The licensees application does not provide the technical justification to show that the acoustic circuit analysis is reliable in determining SSES steam dryer pressure loads caused by such hydrodynamic sources.

2.

The final element analyses (FEA) in Attachment 10, Section 4.3 of the licensees submittal is incomplete as it does not include the application of sufficiently small variations in the steam dryer load definitions time step size to evaluate the potential for more significant stress areas in the steam dryer. As indicated during the public meeting on November 6, 2006, the licensee plans to include the smaller variations in the time step size as part of the final FEA in January 2007.

3.

The licensee's calculations indicate that the fatigue stress limits will be exceeded within the SSES 1 and 2 steam dryers during EPU operation. The licensee indicates that the overstressed areas will require further analysis and modifications to, or replacement of, the steam dryer. The pending analysis is needed by the NRC staff to assure no different or additional stresses result from the modification or new dryer, that the overstress results will be resolved, and that steam dryer structural integrity will be maintained at the full EPU conditions.

In addition to the above, specific examples of areas in the October 11, 2006, application which require further technical discussion are provided below:

1.

Significant uncertainties exist in determining the stress in the steam dryer from scale model testing and main steam line pressure fluctuation analysis. The licensee should address its means of estimating the uncertainties and bias errors, and applying those uncertainties and bias errors in calculating stresses attributed to acoustic dryer pressure loads calculated based on acoustic circuit model assumptions (Table 4-13 component symbol U2b of Attachment 10 of the application) to provide confidence that the allowable limits will not be exceeded in the SSES 1 and 2 steam dryers at EPU conditions.

2.

The licensees submittal indicates the presence of a strong spectral peak at about 110 Hz in the SSES 1 and 2 plant measurements on the steam dryer. The licensee should discuss the source of this peak and the absence of its prediction in the analysis.

3.

Operating experience has not revealed past significant concerns with hydrodynamic loads in low frequency ranges on steam dryer performance. The licensee should discuss the presence of a hydrodynamic excitation source at SSES 1 and 2 that predict steam dryer stresses near fatigue limits at power uprate conditions.

4.

The licensee's submittal indicates spectral peaks near 15 Hz in the two main steam lines at SSES with "dead" legs. The licensee should discuss the source of these peaks and the reason that they do not appear for the other two steam lines. Also, the licensee should discuss how the 15 Hz loading is considered in the load definition of the SSES 1 and 2 steam dryers under EPU conditions.

5.

In Attachment 10, Section 4.2.1, the licensee discusses its selection of Strouhal number to identify the steam velocities for acoustic resonance to occur in the SSES steam lines.

The licensee should discuss the basis for application of the same Strouhal number for various steam line branch openings, including the dead leg.

6.

In Attachment 10, Section 3.7, the licensee discusses anomalies in the steam dryer in SSES Unit 1 upon initial plant operation, and the installation of steam dryer instrumentation to evaluate dryer performance during testing in 1985. The licensee should provide its report regarding the instrumented steam dryer test performed at Susquehanna in 1985, and the related steam dryer issues.