Information Notice 1994-30, Leaking Shutdown Cooling Isolation Valves at Cooper Nuclear Station

Leaking Shutdown Cooling Isolation Valves at Cooper Nuclear Station

ML031060492
Person / Time
Site:	Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant
Issue date:	08/19/1994
From:	Grimes B K Office of Nuclear Reactor Regulation
To:
References
IN-94-030, Suppl 1, NUDOCS 9408160070
Download: ML031060492 (9)

UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555August 19, 1994NRC INFORMATION NOTICE 94-30, SUPPLEMENT 1: LEAKING SHUTDOWN COOLINGISOLATION VALVES ATCOOPER NUCLEAR STATION

Addressees

All holders of operating licenses or construction permits for nuclear powerreactors.

Purpose

The U.S. Nuclear Regulatory Commission (NRC) is issuing this informationnotice (IN) supplement to clarify the type of valve discussed in the originalnotice and to alert recipients to the potential that local leak rate testingof primary containment isolation valves with pressure applied in the directionopposite of the accident direction may not be conservative. It is expectedthat recipients will review the information for applicability to theirfacilities and consider actions, as appropriate, to avoid similar problems.However, suggestions contained in this information notice are not NRCrequirements; therefore, no specific action or written response is required.BackgroundThe NRC issued IN 94-30, "Leaking Shutdown Cooling Isolation Valves at CooperNuclear Station," on April 12, 1994, to alert addressees to a precursor to anunisolable rupture of shutdown cooling piping with the potential for coredamage and release of radioactive material outside the containment. In thatevent, after receiving a high-pressure alarm for the suction piping in theresidual heat removal system, the licensee measured the leakage through theinboard isolation valve, established a bleedoff path into the pressuremaintenance system and continued operations. About 10 months later, thelicensee disassembled the inboard and outboard valves and found cracks in theseating surfaces of both valves.During the preparation of IN 94-30, the staff determined that a concern mayexist regarding the method used for testing of primary containment isolationvalves. This concern is described below. In addition, the NRC has receivedinformation from Anchor/Darling Valve Company that the description of thevalves in IN 94-30, "Anchor-Darling 20-inch nominal, double-disk, flex-wedge,gate valves," is incorrect. The correct description is, "a 20 inch, 900class, flex wedge gate valve," manufactured by the Anchor Valve Company beforethe merger that formed the Anchor/Darling Valve Company. In IN 94-30, the NRCstaff was concerned about the actions of the licensee after the valve leakagewas identified regardless of the valve type or manufacturer.Gs tAiJ4-:&ge q 3 0199408160070illpt- -( IN 94-30, Supplement 1August 19, 1994

Description of Circumstances

On May 1, 1993, after evaluating the results of local leak rate testing forseveral inboard primary containment isolation valves, the licensee for theCooper Nuclear Station (Cooper) determined that the testing methodology usedfor Appendix J, Type C tests of certain flex-wedge gate valves could not berelied on to be equivalent to or more conservative than testing the valves inthe accident direction. The Type C tests for several such valves had beenperformed with the pressure applied in the direction opposite to the accidentdirection (reverse direction). The licensee began corrective actions andnotified the NRC in Licensee Event Report (LER)93-019, dated June 1, 1993.In LER 93-019, the licensee reported that the testing of these valves in thereverse direction was based on an incorrect interpretation of information fromthe valve manufacturer. In response to a question from the licensee regardingthe acceptability of valve test methods, the manufacturer had indicated thattesting in the reverse direction would not be expected to affect test results,but an unqualified answer could not be provided. Results of recent tests bythe licensee of some of the primary containment isolation valves with pressureapplied in the accident direction, indicate that testing in the reversedirection may not be equivalent to or more conservative than testing in theaccident direction; therefore earlier test results may not be valid.LER 93-019 indicated that Cooper Nuclear station has 65 inboard primarycontainment valves of various types and from various manufacturers. Thelicensee found that 24 of those valves were of concern. Of the 24 valves,8 could be tested in the accident direction but, before the 1993 refuelingoutage, were not. The other 16 valves could not be tested in the accidentdirection nor had testing in the reverse direction been qualified to beequivalent or more conservative than testing in the accident direction. Formost of these valves, the licensee qualified testing in the reverse directionto be equivalent or more conservative or modified the testing configuration toallow testing the valve in the accident direction. For the remaining valves,the licensee requested exemptions from certain Appendix J requirements toallow leak .rate testing in the reverse' direction.Discussion'Appendix J to Title 10 of the Code of Federal Regulations Part 50 requires aprogram for leak testing the primary reactor containment and related systemsand components penetrating the primary containment pressure boundary.Section III.C.1 of Appendix J specifies that, for Type C tests of valves(local leak rate tests), the pressure shall be applied in the same directionas that when the valve would be required to perform its safety function,unless it can be determined that the results from the tests for a pressureapplied in a different direction will provide equivalent or more conservativeresults. This requirement is intended to ensure that test leak rates arerepresentative of leak rates that would be experienced under actual accidentconditions. As described above, the licensee for Cooper found that, for someof the primary containment isolation valves, testing in the reverse directionwas not equivalent to or more conservative than testing in the accidentdirectio IN 94-30, Supplement 1August 19, 1994 Related Generic Communications* NRC IN 86-16, "Failures to Identify Containment Leakage Due toInadequate Local Leak Rate Testing," March 11, 1986.* NRC IN 92-20, Inadequate Local Leak Rate Testing,' March 3, 1992.This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian s, Director QDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact: Jim Pulsipher, NRR(301) 504-2811

Attachment:

List of Recently Issued NRC Information Noticess&C 3 Lo AttachmentIN 94-30, Supp. 1August 19, 1994 LIST OF RECENTLY ISSUEDNRC INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to94-5994-5894-5794-5694-55Accelerated Dealloying ofCast Aluminum-BronzeValves Caused by Micro-biologically InducedCorrosionReactor Coolant PumpLube Oil FireDebris in Containmentand the Residual HeatRemoval SystemInaccuracy of Safety ValveSet Pressure DeterminationsUsing Assist DevicesProblems with Copes-Vulcan PressurizerPower-Operated ReliefValvesDeficiencies Found inThermo-Lag Fire BarrierInstallationFailures of GeneralElectric Magne-BlastCircuit Breakers toLatch ClosedPossible Malfunction ofWestinghouse ARD, BFD,and NBFD Relays, andA200 DC and DPC 250Magnetic Contactors08/17/9408/16/9408/12/9408/11/9408/04/9408/04/9408/01/9407/29/94All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor pressurized waterreactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.91-79,Supp. 194-5491-45,Supp. 194-42,Supp. 1Cracking in the LowerRegion of the Core Shroudin Boiling-Water Reactors07/19/94All holdersfor boiling(BWRs).of OLs or CPswater reactorsOL = Operating LicenseCP = Construction Permit V IN '-30, Supplement 1August 19, 1994 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.orig /s/'d by CIGrimes/forBrian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact: Jim Pulsipher, NRR(301) 504-2811

Attachment:

List of Recently Issued NRC Information NoticesSPraa Proevintic rnnmirronreOFFICE SCSB:DSSA:NRR SCSB:DSSA:NRR C/SCSB:DSSA:NRR D/DSSA:NRRNAME I JPulsifer* RLobel* RBarrett* GHolahan*DATE 07/17/94 1 07/19/94 08/03/94 08/04/94OFFICE I TECH ED OGCB:DORS:NRR AC/OGCB:DORS:NRR D/DORS:JNI2,aNAME RSanders* JBirmingham* ELDoolittle* BKGrimesDATE 6/14/94 1 08/03/94 08/04/94 ,08/ t194UN .-ILALUUU A'4 rptt ^t- u IitOFFIIAL UULUMMNI NAMEL:Y4-30SH .AN I " 4-30, Supplement 1August XX, 1994 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:Jim Pulsipher, NRR(301) 504-2811

Attachment:

List of Recently Issued NRC Information Notices* See Previnus ConcurrenceOFFICE SCSB:DSSA:NRR SCSB:DSSA:NRR C/SCSB:DSSA:NRR D/DSSA:NRRNAME JPulsifer* RLobel* RBarrett* GHolahan*DATE 07/17/94 07/19/94 , 08/03/94 08/04/94OFFICE TECH ED OGCB:DORS:NRR AC/OGCB:DORS:NRR D/DORS:NRRNAME RSanders* JBirmingham* ELDoolittle* BKGrimesDATE 06/14/94 08/03/94 1 08/04/94 08/ /94v_ -ace--- --..- .^ ... _ eae .-.n ... ... -AOFFICIAL OUCUMNI NArt:U:\1N Y4JUb.LUb IN"4-30, Supplement 1August XX, 1994 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:Jim Pulsipher, NRR(301) 504-2811

Attachment:

List of Recently Issued NRC Information NoticesA* See Previnut CnncurrenceOFFICE SCSB:DSSA:NRR SCSB:DSSA:NRR C/SCSB:DSSA:NRR RRNAME JPulsifer* RLobel* RBarrett* GHolahanDATE 07/17/94 07/19/94 08/03/94 08/e/94OFFICE TECH ED OGCB:DORS:NRR AC lBO DORS:NRR D/DORS:NRRNAME RSanders* JBirmingham* E 6 ttle BKGrimesDATE 06/14/94 08/03/94 08/4 /94 08/ /94OICA DO. MN NAE G.. ._ ..4. ..JOFFICIAL DOCUMENT NAME:6:\IN 9430S.JLB IN 44-30, Supplement 1August XX, 1994 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:Jim Pulsipher, NRR(301) 504-2811

Attachment:

List of Recently Issued NRC Information Notices* See Previous ConcurrenceAOFFICE lSCSB:DSSA:NRR SCSB:DSSA:NRR C/SCS A:NRR AD/DSSA:NRRNAME JPulsifer* RLobel* l aWVrgllolDATE 07/17/94 07/19/94 !08/;7/94 08/ /94OFFICE TECH ED OGCB:DORS:NRR AC/OGCB:DORS:NRR D/DORS:NRRNAME RSanders* JBirmingham ELDoolittle BKGrimesDATE 06/14/94 08/ 3 /94 .08/ /94 08/ /94a.-.-. a. a. anna ...r&*, a.r. **a A 1A .i 1 DoUMLI16AL UUUUMtN1 I `t:IN Y4JV3 .UL0 IN 94-30, Supplement 1June XX, 1994 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:Jim Pulsipher, NRR(301) 504-2811

Attachment:

List of Recently Issued NRC Information Notices* See Previous Concurrence 1i'OFFICE S 5 SCSB:DSSA:NRR C/SCSB:DSSA:NRR D/DSSA:NRRNAME JPulsige ZtG RBarrett MVirgiliol DATE _ _06/17/94 i /94/06/ /94 06/ /94OFFICE TECH ED 9 OGCB:DORS:NRR C/OGCB:DORS:NRR D/DORS:NRRNAME RSander JBirmingham RDennig BKGrimesDATE 06/14/94 I06/ /94 06/ /94 06/ /94OFF116lAL VULUMtNI NAMLiNr3 JU1.dJLU