ML062070524

Approval of Generic Letter 2004-02 Extension Request

ML062070524
Person / Time
Site:	Salem
Issue date:	08/11/2006
From:	Stewart Bailey NRC/NRR/ADRO/DORL/LPLI-2
To:	Levis W Public Service Enterprise Group
Bailey S N,NRR/DLPM,415-1321
References
GL-04-002, GSI-191, IN-05-026, TAC MC4713
Download: ML062070524 (5)

Text

August 11, 2006Mr. William LevisSenior Vice President & Chief Nuclear Officer PSEG Nuclear LLC - N09 Post Office Box 236 Hancocks Bridge, NJ 08038

SUBJECT:

SALEM NUCLEAR GENERATING STATION, UNIT NO. 2 - APPROVAL OFGENERIC LETTER 2004-02 EXTENSION REQUEST (TAC NO. MC4713)

Dear Mr. Levis:

In a June 7, 2006, updated response to the Nuclear Regulatory Commission (NRC) GenericLetter (GL) 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized Water Reactors," PSEG Nuclear LLC (PSEG or the licensee) provided updated information on its ongoing activities for resolution of the Generic Safety Issue (GSI)-191 containment sump clogging issue. In addition to reporting on certain completed additional actions taken in response to GL 2004-02, PSEG requested an extension beyond December 31, 2007, for removal of certain insulation in the containment of Salem Nuclear Generating Station (Salem), Unit No. 2, until the next refueling outage scheduled tobegin on March 12, 2008. This results in an extension of approximately 10 weeks.PSEG stated that a design change package for Salem Unit No. 2 has been issued forinstallation of a 5300 square foot strainer with 1/12-inch openings during the fall 2006 outage.

PSEG also stated that trisodium phosphate is not used as a pH buffer at Salem, reducing theexpectation of significant quantities of chemical precipitate as discussed in NRC InformationNotice (IN) 2005-26 and IN 2005-26, Supplement 1. PSEG stated that it will remove all calciumsilicate within the loss-of-coolant accident (LOCA) zones of influence by December 31, 2007. PSEG further stated that, as a result of a planned July 2006 loop testing of representative fiber, combined with Salem-specific chemical precipitates (from interactions with the sodium hydroxide pH buffer), the new strainer design was expected to have adequate margin for chemical effects. PSEG stated that the Salem downstream-effects evaluations have been completed and have been found acceptable for ex-vessel blockage and wear of downstream components. PSEG discussed a non-Salem-specific, conservative Westinghouse initial scoping evaluation ofthe long-term core coolability of the fuel with fibrous and particulate debris in the recirculationfluid. The evaluation concluded that passage of about one cubic foot or more of fibrous debriscould result in a thin-bed effect at the bottom of the fuel. PSEG stated that testing performed with the replacement strainer design for Salem with the current (non-calcium silicate insulation)fiber load has demonstrated a fibrous debris bypass of approximately five cubic feet. PSEG stated that there were ongoing actions underway to address this discrepancy:

W. Levis *PSEG discussions with Westinghouse indicated that the assumptions for the formationof a 1/8-inch fiber bed at the bottom of the fuel are conservative, and can possibly be relaxed when considering the physical characteristics of the actual fibrous debris that would bypass the strainer. The vendor test results show that 90% of the Salem bypass fibers are relatively short (.004 to .04 inches) compared to fuel bottom nozzle flow holes of 0.2 inches. The licensee stated that these fibers will not mat across the fuel bottom nozzles, as was assumed in the Westinghouse scoping evaluation.*Westinghouse is developing Salem-specific acceptance criteria to quantify theacceptable amount of fiber bypass for long-term cooling, but the analyses are not expected to be completed until as late as September 2006. PSEG stated that it expectsthe results from the Salem bypass testing to be acceptable under these revised acceptance criteria.PSEG stated that it was confident that no additional insulation would need to be removed tocomply with the expected new allowable fiber bypass acceptance criteria. However, assuming that application of the Salem-specific fiber bypass acceptance criteria results in a need to remove additional insulation, two sets of insulation would need to be replaced. PSEG requested to defer replacement of this insulation for the following reasons:*One set of insulation that would need to be replaced is the steam generator insulation.PSEG has scheduled replacement of the Salem Unit No. 2 steam generators during the spring 2008 outage. The replacement steam generators are to be insulated with custom-engineered reflective metal insulation. If the current Salem Unit No. 2 steam generators insulation were to be replaced in the normally-scheduled fall 2006 refueling outage, the new insulation would need to be removed and replaced again when the steam generators are replaced in the spring 2008 outage. PSEG stated that this wouldresult in 22 REM of additional exposure, and generation of approximately 1800 cubic feet of radiological waste.*The other set of insulation that would need to be replaced is the pressurizer andpressurizer piping insulation. PSEG stated that replacing this insulation will result inapproximately 50 REM of additional exposure. PSEG stated that the likelihood of a LOCA would be low during the requested extension period(January 1 to March 12, 2008). The NRC staff notes that Salem Unit No. 2 has been acceptedas leak-before-break reactor primary coolant loop plant, as was discussed in an NRC letter toPSEG dated May 25, 1994. PSEG stated that the small incremental risk during the requestedextension period resulting from not installing interim insulation would more than offset avoidance of additional radiation exposure to plant workers.The NRC has confidence that PSEG has a plan that will result in the installation of finalmodifications that provide acceptable strainer function with adequate margin for uncertainties to resolve the GSI-191 containment sump clogging issue. Further, the NRC has concl uded thatPSEG has put mitigation measures in place to adequately reduce risk for the requested short extension period. Therefore, the NRC concludes that it is acceptable to extend the completiondate for the corrective actions (specifically, the replacement of insulation on the steam generators, pressurizer, and pressurizer piping) for the issues discussed in GL 2004-02 until the completion of the Salem Unit No. 2 spring 2008 refueling outage, which is currently scheduled W. Levis to begin approximately March 12, 2008. Should PSEG elect to begin the Salem, Unit No. 2outage more than 30 days after March 12, 2008, PSEG will need to provide the NRC additionaljustification for further delay in completing corrective actions for GL 2004-02.If you have any questions regarding this matter, please contact me at 301-415-1321, or atsnb@nrc.gov.

Sincerely,/RA/Stewart N. Bailey, Senior Project ManagerPlant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor RegulationDocket No. 50-311 cc: See next page W. Levis to begin approximately March 12, 2008. Should PSEG elect to begin the Salem, Unit No. 2outage more than 30 days after March 12, 2008, PSEG will need to provide the NRC additionaljustification for further delay in completing corrective actions for GL 2004-02.If you have any questions regarding this matter, please contact me at 301-415-1321, or atsnb@nrc.gov.

Sincerely,/RA/Stewart N. Bailey, Senior Project ManagerPlant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor RegulationDocket No. 50-311 cc: See next page DISTRIBUTION

PUBLICRidsNrrLACRaynorRidsNrrDorlLpl1-2 RidsNrrPMSBaileyRidsAcrsAcnwMailCenterLPL1-2 R/F RidsOgcRpRidsRgn1MailCenterLWhitneyADAMS Accession Number: ML062070524 *concur by memoOFFICELPL1-2/PMLPL1-2/LASSIB/BCLPL1-2/BC (A)NAMESBailey:rsaCRaynorMScott *BPooleDATE8/11/068/11/0607/07/068/11/06OFFICIAL RECORD COPY Salem Nuclear Generating Station, Unit No. 2 cc:

Mr. Dennis WinchesterVice President - Nuclear Assessment PSEG Nuclear

P.O. Box 236 Hancocks Bridge, NJ 08038Mr. Thomas P. JoyceSite Vice President - Salem PSEG Nuclear

P.O. Box 236 Hancocks Bridge, NJ 08038Mr. George H. GellrichPlant Support Manager PSEG Nuclear

P.O. Box 236 Hancocks Bridge, NJ 08038Mr. Carl J. FrickerPlant Manager - Salem PSEG Nuclear - N21

P.O. Box 236 Hancocks Bridge, NJ 08038Mr. Darin BenyakDirector - Regulatory Assurance PSEG Nuclear - N21

P.O. Box 236 Hancocks Bridge, NJ 08038Mr. James MallonManager - Licensing 200 Exelon Way, KSA 3-E Kennett Square, PA 19348Mr. Steven MannonManager - Regulatory Assurance

P.O. Box 236 Hancocks Bridge, NJ 08038Jeffrie J. Keenan, EsquirePSEG Nuclear - N21

P.O. Box 236 Hancocks Bridge, NJ 08038Township ClerkLower Alloways Creek Township Municipal Building, P.O. Box 157 Hancocks Bridge, NJ 08038Mr. Paul Bauldauf, P.E., Asst. DirectorRadiation Protection Programs NJ Department of Environmental Protection and Energy CN 415 Trenton, NJ 08625-0415Mr. Brian BeamBoard of Public Utilities 2 Gateway Center, Tenth Floor Newark, NJ 07102Regional Administrator, Region IU.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406Senior Resident InspectorSalem Nuclear Generating Station U.S. Nuclear Regulatory Commission Drawer 0509 Hancocks Bridge, NJ 08038