ML17058B813

Summary of 930610 Meeting W/Util in Rockville,Md Re Discussion of Insp & Possible Repair of Flaw in High Pressure Core Spray Nozzle Weld KC-32 at Plant

ML17058B813
Person / Time
Site:	Nine Mile Point
Issue date:	06/21/1993
From:	Menning J Office of Nuclear Reactor Regulation
To:	Office of Nuclear Reactor Regulation
References
NUDOCS 9306290199
Download: ML17058B813 (70)

Text

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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, O. C. 20555 June 21, 1993 Docket No. 50-410 LICENSEE:

Niagara Mohawk Power Corporation FACILITY:

Nine Mile Point Nuclear Station, Unit 2

SUMMARY

OF JUNE 10,

1993, MEETING TO DISCUSS THE INSPECTION AND POSSIBLE REPAIR OF A FLAW IN HIGH PRESSURE CORE SPRAY NOZZLE WELD KC-32 AT NINE MILE POINT NUCLEAR STATION, UNIT 2 A meeting was held in the NRC One White Flint North Office in Rockville, Maryland, with Niagara Mohawk Power Corporation (NMPC) and NRC staff representatives to discuss the inspection and possible repair of a flaw in the weld (KC-32) joining the high pressure core spray nozzle safe end to safe end extension at Nine Mile Point Unit 2 (NMP-2).

The licensee had requested this meeting.

Enclosure 1 is a list of meeting attendees.

Enclosure 2 is a copy of the handout material provided by NHPC.

BACKGROUND The flaw in weld KC-32 was discovered during the first NMP-2 refueling outage in October 1990 and subsequently treated with the Mechanical Stress Improvement Process (MSIP).

Ultrasonic examination (UT) after HSIP showed an indication depth of 41 percent of the wall thickness and a length that was 11.3 percent of the weld circumference.

Ultrasonic reexaminations midway through the second operating cycle and during the second refueling outage revealed no growth in the flaw.

The staff has reviewed and approved NHPC submittals that provided justification for continued operations since discovery of the flaw.

The staff's most recent letter regarding operations with the flaw was dated Hay 6, 1992.

In the letter of May 6, 1992, the staff agreed with NHPC's proposal to operate NMP-2 for up to 9700 hours0.112 days <br />2.694 hours <br />0.016 weeks <br />0.00369 months <br /> during the current (third) operating cycle.

Operations beyond 9700 hours0.112 days <br />2.694 hours <br />0.016 weeks <br />0.00369 months <br /> required NMPC to either justify such operations prior to exceeding 9700 hours0.112 days <br />2.694 hours <br />0.016 weeks <br />0.00369 months <br /> of operation or to repair or replace the weld prior to exceeding 9700 hours0.112 days <br />2.694 hours <br />0.016 weeks <br />0.00369 months <br /> of operation.

The staff's letter of Hay 6,

1992, noted that NHPC had committed to repair or replace weld KC-32 during the third refueling outage if it is not repaired or replaced during the third operating cycle.

By letter dated March 16,

1993, NHPC provided the staff with the results of a

. fracture mechanics analysis that provided a basis for operations beyond 9700 hours0.112 days <br />2.694 hours <br />0.016 weeks <br />0.00369 months <br /> during the third operating cycle.

The staff is currently evaluating this NMPC proposal for continued operations.

The NMPC letter of.-

Harch 16,

1993, also advised the staff that NHPC was reevaluating the merits, of replacing the safe end extension during the third refueling outage.

NHPC 0~~0 R4li G~iki7i'iI"i'i Li"h/V

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expressed concern at that time that replacement of the safe end extension, without fully evaluating other possible options, could result in excessive costs, significant radiation exposure, and extension of the refueling outage with no net safety gain.

NHPC committed to provide additional information to the staff regarding these evaluations in the near future.

MEETING DISCUSSIONS The NHPC representatives initially indicated that they intended to provide the staff with NHPC's assessment of the flaw in weld KC-32 and to discuss their commitment to replace the safe end during the third refueling outage.

NHPC then reviewed the history of the flaw, including the UT examinations that have been performed.

NHPC indicated that the weld was ultrasonically scanned many times during each examination and that both automated and manual UT data indicate that the flaw depth is no greater than 41 percent of the wall thickness, and not growing in length.

'NHPC then discussed the results of a finite element inelastic analysis that considered welding residual

stresses, HSIP application, and operating loads.

The results of this analysis indicated that the flaw in weld KC-32 remains in the compressive stress region and that no further fracture mechanics analysis is necessary.

NHPC stated that they intended to propose to the staff that the weld not be repaired during the third refueling outage if examination of the flaw shows no increase in length or depth.

If any growth is observed, NMPC would then implement a weld overlay repair plan.

NHPC reviewed some of its incentives for repairing weld KC-32 instead of replacing it.

For instance, repair would involve approximately 4.3 person rem of exposure, and replacement would involve about 43.75 person rem.

Repair would increase critical path outage time by about 7 days and replacement would involve an increase of approximately 21 critical path days.

NMPC also indicated that repair would not require cutting into the reactor coolant pressure

boundary, and that the risks associated with implementing a repair are lower than those associated with replacement.

NHPC summarized their position relative to inspection and repair of the flaw near the conclusion of the meeting.

Specifically, results of the finite element inelastic analysis and UT examinations indicate the flaw growth has been arrested.

Based on mitigation of flaw growth, NHPC has reassessed its commitment to replace the safe end extension and will propose to repair the weld with an overlay durirtg the third refueling outage if examination of the

I June 21, 1993 flaw reveals growth in length or depth.

No repair would be performed if the examination shows no increase in length or depth.

NMPC indicated that a

written submittal for the staff's consideration would likely be forwarded in 3 to 4 weeks.

Enclosures:

1.

List of Attendees 2.

Licensee Handout Material John E. Menning, Project Manager Project Directorate I-1 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation cc w/enclosures:

See next page

I J'

Niagara Mohawk Power Corporation Nine Mile Point Nuclear Station Unit No.

2 CC:

Har k J. Wetterhahn, Esquire Winston 5 Strawn 1400 L Street, NW.

Washington, DC 20005-3502 Mr. Richard Goldsmith Syracuse University College of Law E. I. White Hall Campus

Syracuse, New York 12223 Resident Inspector Nine Mile Point Nuclear Station P. 0.

Box 126

Lycoming, New York 13093 Gary D. Wilson, Esquire Niagara Mohawk Power Corporation 300 Erie Boulevard West

Syracuse, New York 13202 Hr. David K. Greene Manager Licensing Niagara Mohawk Power Corporation 301 Plainfield Road

Syracuse, New York 13212 Hs.

Donna Ross New York State Energy Office 2 Empire State Plaza 16th Floor

Albany, New York 12223 Supervisor Town of Scriba Route 8, Box 382

Oswego, New York 13126 Regional Administrator, Region I U. S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Charles Donaldson, Esquire Assistant Attorney General New York Department of Law 120 Broadway New York, New York 10271 Hr. Richard H. Kessel Chair and Executive Director State Consumer Protection Board 99 Washington Avenue

Albany, New York 12210 Mr. Hartin J.

HcCormick Jr.

Plant Manager, Unit 2 Nine Nile Point Nuclear Station Niagara Mohawk Power Corporation P. 0.

Box 32

Lycoming, New York 13093 Hr. Neil S.

Car ns Vice President - Nuclear Generation Nine Mile Point Nuclear Station Niagara Mohawk Power Corporation P. 0.

Box 32

Lycoming, New York 13093 Hr. B. Ralph Sylvia Executive Vice President, Nuclear Niagara Mohawk Power Corporation 301 Plainfield Road

Syracuse, New York 13212

ENCLOSURE 1

June 10 1993 Ins ection and Possible Re air of a Flaw in a Hi h Pressure Core S ra Nozzle Weld at Nine Mile Point Unit 2 ATTENDANCE LIST Name Robert Capra John Henning Jack Strosnider Robert Hermann William Koo Robert HcBrearty Carl Terry Keith Ward David Greene W. David Baker S.

K. Dhar Gary Wilson Kenneth Korcz John Swenskowski Manu Badlani Mark Wetterhahn Michael Heath Position Project Director Project Manager Branch Chief Section Chief Sr. Materials Engineer Reactor Engineer Vice President Nuclear Engineering Manager - Nuclear Engineering for Unit 2 Licensing Manager Program Director Engineer Attorney Licensing Engineer NDE Lead Consultant Attorney ISI Project Manager Or anization NRC/NRR/PD I-1 NRC/NRR/PDI-1 NRC/NRR/EHCB NRC/NRR/EHCB NRC/NRR/EHCB NRC/Region I Niagara Hohawk Niagara Mohawk Niagara Mohawk Niagara Mohawk Niagara Mohawk Niagara Mohawk Niagara Mohawk Niagara Mohawk A.A. O'Donnell Winston and Strawn General Electric

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ENCLOSURE 2 NIAGARAMOHAWKPOWER CORPORATION I.'AIMMILEPOPULI'UCLEAR STATION HIGH PRESSUIM CORE SPRAY SAFE END TO SAFE END EXTENSION VVELD 2-RPV-KC32 JUNE 10, 1993 V NIAGARA MOHAWK

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NIAGAIMMOHAWKPOWER CORPORATION HPCS CORE SPRAY NOZZLE MEETING AGENDA JUNE 10, 1993 PEAKE I.

INTRODUCTION/PURPOSE K. D. WARD II.

BACKGROUND INFORMATION K. D. WARD III.

ULTRASONIC TESTING M. HEATH (GENERAL ELECTRIC)

IV. MECHANICALSTRESS IMPROVEMENT M. BADLANI ANALYSIS (AEA O'DONNELL, INC)

V. CONTINGENCY REPAIR PLAN K. D. WARD VI.

SUMMARY

K. D. WARD Page 2

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PURPOSE Page 3

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E TO PROVIDE NMPC'S ASSESSMENT OF THE HPCS SAFE END TO SAFE END EXTENSION WELD FLAW AND DISCUSS OUR COMMITMENTTO REPLACE THE SAFE END AT REFUEL OUTAGE 3:

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FLAW HAS BEEN ARRESTED BY MECHANICAL, STRESS IMPROVEMENT PROCESS

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REPAIR OR REPLACEMENT IS NOT REQUIRED PROVIDING THE PROPOSED INSPECTION ACCEPTANCE CRITERjA ARE MET

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REPAIR BY WELD OVERLAYIS ACCEPTABLE ALTERNATIVETO REPLACEMENT SHOULD ACCEPTANCE CRITERllA NOT BE MET Page 4

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BACKGROVM)PS'ORMATION ON N ZZLEK -2

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FLAW WAS DISCOVERED DURING FIRST REFUELING OUTAGE IN-SERVICE INSPECTIONS (OCTOBER 1990).

MECHANICALSTRESS IMPROVEMENT PROCESS (MSIP) WAS APPLIED TO MITIGATECRACK GROWTH.

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INITIALFRACTURE MECHANICS ANALYSIS SUBMITTED TO NRC ON DECEMBER 28, 1990.

REVISED ANALYSIS SUBMITTED ON JUNE 28, 1991 TO:

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ASSESS FLAW WITH AS-WELDED RESIDUAL STRESS FOR SMALLDIAMETERPIPE AS SPECIFIED IN NUREG 1061

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INCREASE MAXIMUMUT INDICATIONSIZE BY 5% IN DEPTH AND LENGTH TO ADD ADDITIONALMARGIN

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RESPONSE TO NMPC IN NRC LETTER OF MAY6, 1992, P'K)ICATED NMPC'S COMMITMENTTO REPLACE SAFE END EXTENSION IN THE THIRD REFUELING OUTAGE

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NMPC HAS REEVALUATEDREPLACEMENT OF SAFE END EXTENSION BASED ON SAFETY, EXPOSURE AND COST CONSIDERATIONS Page 6

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( HIGH PRESSURE CORE SPRAY)

RPV-KC32 SAFE END EXTENSlON

( SA588 CLASSl) 18" SCH88 PlPE SA)86GRB I

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SaFE END

( SB166 INCONEL-)

31 23/32" RPV-KB32 NOZZLE (SA588.

CLaSS II)

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ULTRASONIC TESTING Page 7

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ULTRASONIC EXAMINATIONSOF WELD 2-RPV-2

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UT EXAMINATIONSWERE PERFORMED IN ACCORDANCE WITH THE ASME SECTION XI CODE, WITH ENHANCEMENTS ENDORSED BY THE EPRI NDE CENTER

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ALLOF THE EXAMINERS, EQUIPMENT, AND PROCEDURES WERE QUALIFIEDAT THE EPRI NDE CENTER ON SAMPLES WITHACTUAL CRACKS OF KNOWN DEPTHS

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IN ADDITIONTO THE ABOVE, ALL(4) OF THE EXAMINERS OF RECORD WERE CERTIFIED LEVELIII'S IN THE ULTRASONIC METHOD INSPECTION CRACK DEPTH CRACK LENGTH 1ST REFUEL OUTAGE 41% (.35")

11.3% (3.4")

POST MSIP (1990)

MID-CYCLE (1991) 2ND REFUEL OUTAGE (1992) 38% (.32")

29% (.25")

Page 8 11.0% (3.3")

11.0% (3.3")

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ULTIbLSONICEXAMINATIONSOF WELD

-RPV-K 2

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VAKlATIONSIN MAXIMUMDEPTH OF.1 INCH ARE NOT UNEXPECTED FOR A NARROW FLAW

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IN ADDITIONTO THE SIZING EXAMINATIONS, OVER 30 AUTOMATEDUT SCANS HAVE BEEN PERFORMED ON THIS WELD TO DATE

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NO TRANSDUCER READINGS HAVE SHOWN THIS INDICATIONTO BE DEEPER THAN 41%T, AND (9)

SEPARATE TRANSDUCER READINGS HAVE INDICATEDTHIS FLAW TO BE SHALLOWER

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EPRI PERSONNEL HAVE REVIEWED ALLOF THE COLLECTED DATATO DATE, AND THEY CONCUR THAT THE VAKATIONNOTED IS REASONABLE

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BOTH AUTOMATEDAND MANUALDATA INDICATETHE FLAW DEPTH TO BE NO DEEPER TKAN41%T, AND NOT GROWING IN THE LENGTH DIRECTIONS Page 9

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ULTRASONIC EXAMINATIONSOF MELD

-RPV-K 2

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BASED ON THE ABOVE, WE ARE CONFIDENT THAT THIS INDICATIONIS NO DEEPER THAN 41%T AND IS NOT GROWING IN EITHER THE LENGTH OR DEPTH DIRECTIONS Page 10

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MSIP ANALYSIS FOR CORE SPRAY SAFE-END-TO-EXTENSION W'ELDMENT Page 11

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VERIFI ATI N NALY E

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FINITE ELEMENT INELASTIC ANALYSIS TECH

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MgC12 TEST EPRI

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RESIDUAL STRESS MEASUREMENTS ARGONNE NATIONALLABORATORYFOR NRC EPRI FOR BWR OWNERS GROUP ERATI

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PROCESS APPLIED FOR WELDMENTS WITH AND WITHOUT CRACKS FOR ABOUT 1,000 JOINTS TESTS &, OPERATION EXPERIENCE QUALIFIEDTHE METHOD OF ANALYSIS USED FOR INDIVIDUAL WELDMENTS MARTINMARIETTAKNOLLS 8c WESTINGHOUSE IMPRO BETTIS VERIFICATIONOF MECHANICALSTRE ROVEMENT PROCESS FOR NAVYSPECIFICATION TRESS Page 12

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USE OF MECHAI.'ICALSTRESS D/KPROVEMENT PROCESS IN NUCLEAR PLAZA'S Plant Year Pipe &

Nozzles I Total l Notes Fimnas and S.E.s I

I CECo I

Dresden 3 I

1986 I

50 I

2 CECo I

LaSalle 2 1987

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25 I

29 CECo I

Quad Cities 1 1987 I

36 I

2 CP&L I

Brunswick 2 I

1988 I

0 I

15 CECo I

Quad Cities 2 1988 I

43 I

4 Nucienor I Santa Maria de Garona 1988 I

24 I

0 52 38 15 47 OKG Aktiebola CP&L CECo CECo CECo PECo Northeast Detroit Edison CECo CP&L CECo Teollisuuden Voima Ov Nia ara i~fohawk Taiwan Power Co CP&L Oskarshamn I

1988 I

1 I

0 Brunswick 1 I

1988 I

0 I

10 LaSalle 1 I

1988 I

15 I

15 LaSalle 2 I

1988 I

8 I

0 Dresden 2 I

1988 I

82 I

22 Limerick 2 I

1989 I

2 I

16 h fillstone 1 I

1989 I

0 I

22 Fermi 2 I

1989 I

6 I

21 Quad Cities 1 I

1989 I

28 I

12 Brunswick 2 I 1989/90 I

16 I

20 Quad Cities 2 I

1990 I

30 i

14 1990 Nine L~file Pt 2 I

1990 I

0 I

1 Kuosh 2

1990 I

2 I

0 Bru~vick 1 I 1990/91 I

10 I

24 10 30 I

104 I

18 22 2/

40 Northeast Iberdrola Boston Edison PECo PECo Cleveland Elec GPU Geor

'a Power 5 fillstone 1 Cofrentes Pil 1

Peach Bottom 3 Limerick I P

I Browns F 3

Hatch 1 1991 1991 1991 1991 1992 1992 1992 1992 1993 81 70 2/

18 I

9 0

I 42 16 10 10 2/

I 110 70 29 TVA Browns Ferrv 2 Totals 1993 12 617 361 I

12 978 Recent Application for PWR Inconel 600 iVozzles and Small Diameter Piping Notes:

1) Some weldments with preexisting cracks

2) Neldments for replacement piping made of SCC immune materials

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CRACKS ARRESTED BY MSIP NOMINAL PIPE SIZE FLAW SIZE CYCLES LENGTH DEPTH OF OPERATION 0.5" 2.1" 5.5"

.09" (15%)

0.25" (20%%u&)

0.1 1" (1 6%%)

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CIACUHFEALATIALCRACK TAFATf'n r v ~cr~

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INELASTIC FINITE ELEMENT ANALYSIS INCLUDING

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WELDING RESIDUAL STRESSES

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MSIP APPLICATION

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OPERATING LOADS Page 13

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SfllKSSI3 Af

%KLO lIDIIEAMC CRPA(

4llOV/QI SlRCS3 DgBNBUQOH AT CRACK LGChlIOII CRACK DEFlll EXCEEDS hOumaSSm AEOIOH CRJ4CK DEPlll HIALY5IS FU)W CILNlf

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CRACK'IP

---. MELD CENTER AHSYS 4.W DEC 18 1938 ww:59:82 PLOT HQ.

2 POST1 STRESS STEP=63 ITFR=288 SY (AVG) 5 GLOBAL DNX =8.848126 SNH =-37785 SN< =37211 ZV

=1 DIST=1. 783

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=5.323 4YF

=-3. 762 EDGE -37785 I~I 29381

~pgg 2 1 857 1 2733

-4489 3S15

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18 " Hozz le iH16 ) v. Extn.

Un 1 ood in (89 )

,=lGURt'.7 POST t45TP AXIAL STRESSES Ilk THE SAFE-EtCD-TO-EXTENSION NFLD (0.788'OI<IIIAQIOII)

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WELD GEttTER ANSYs DEC 18 1398.

PLOT HQ.

2 POST)

STRESS STEP=73 ITER=188 SY (AVG)

S GLOBAL CtN>< =8.>86663 SNN =-28711 SNA =55877 zv DIST=1. VS3 4'5.323 4YF

=-S.?62 EDGE -28711 IINI 1 2238 Im

-3369 4552

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38235 46656 55877 f

18" Nazzle (N16) v. Ext,n. -New 0 er Locids(83) t INURE 3.ll POST NSIP AXIAL STRESSES MITH OPERATING LOAN INCLUOED FOR THF. SAFE-Ft'0 TO-EETEttSIOtt WELD (0.78M CONTRACTIOt<}

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~F t.s EeorgoncM L Faultad 4SNE Swat ion )CI Limit.

F

~ 3 ~ B Norma t L Upset.

8 INaxlmum UT Reaulta Crack Stable t

BoB 6

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NON-DIMENSIONAL CRACK l EHGTH (L>PIED) t.0 Fhll.LIAR ANALYSlS OlAGAAH

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INELASTIC ANALYSISBASED ON THE ACTUAL POST-MSIP DISTRIBUTIONCORI&SPONDING TO FIELD MEASURED PIPE CONTRACTION INDICATES THAT THE CRACK REMAINS IN THE COMPRESSIVE REGION.

NO FURTHER FRACTURE MECHANICS EVALUATION NECESSARY

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UT INSPECTIONS CONFIRM THAT CRACK HAS BEEN ARI&STED

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ANALYSIS RESULTS RECONFIRM THAT SAFE OPERATION CAN BE CONTINUED Page 14

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INSPECTION CRITERIA Page 15

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IN PE TI N RITERIA

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PROPOSING INSPECTION OF FLAW AT THE NEXT OUTAGE

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IF DEPTH C.41T AND LENGTH C.113L, THEN NO FURTHER ACTION

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IF DEPTH ).41T OR LENGTH ).113L, IMPLEMENTREPAIR PLAN

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COMPLETION OF THE CURIKNT CYCLE WILL ENCOMPASS APPROXIMATELY22,000 HOURS OF OPERATION Page 16

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1.8 SF=1

~ 5 EMERGENCY L FAULTED ASME SECTION XI LIMIT SF=3.8 NORMAL 8, UPSET MAXIMUM UT RESULTS CRACK STABLE M S IP COMPRESSIVE REGION 8.g 8.4 8.6 8.8 NON-DIMENSIONAL CRACK LENGTH

( L/PIED)

FAILURE ANALYSIS DIAGRAM 1.8

$ s op

PL N Exposure (manrem)

Increase in Critical Path Days During a Typical Refueling

'utage Cost (dollars)*

REPLACElVEPK 43.75 21 1.5 million REPAIR 4.3 0.6 million Cost does not include loss of power generation revenue due to increase in outage duration

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REPLACEMENT OPTION IS MUCH MORE SIGNIFICANT EVOLUTIONTHAN REPAIR

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THE REPLACEMENT REQUIRES COMPLETE DEFUELING AND DEWATERING OF VESSEL

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REPXBt PLAN DOES NOT REQUIRE CUTTING INTO REACTOR COOLANT PRESSURE BOUNDARY

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ASSOCIATED RISKS OF REPAIR PLAN ARE LOWER THAN REPLACEMENT PLAN Page 17

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REPAIR PLAN Page 18

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REPAIR PLAN PROVIDES PRESSURE BOY'Q)ARY RABL T REPLA EMENT PL

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NMPC SUBMITTED WELD OVERLAYREPAIR PLAN JUNE 10, 1991, (NMP2L 1303) AND ADDRESSED STAFF'S CONCERNS IN MARCH 3, 1992, LETTER (NMP2L 1341)

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WELD OVERLAYIS LONG-TERM REPAIR

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REPAIR WILLMEET DESIGN CRITEKAIN NUREG-0313, REV. 2 Crack Depth Assumed Through Wall Crack Length Assumed to be 360'ircumference Overlay Thickness has Factor of Safety of 3.0 Against Net Section Collapse for Normal and Upset Conditions Factor of Safety of 1.S is Maintained for Emergency and Faulted Conditions Weld Design is a Full Structural Overlay

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CERTIFIED DESIGN REPORT WILL DEMONSTRATE NEW CONFIGURATION MEETS FLAW EVALUATIONCRITEKA OF 1986 ASME CODE, SECTION XI, IWB-3640, FOR CLASS 1 COMPONENTS Page 19

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SUMMARY

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N L I N

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ANALYSIS BASED ON THE ACTUALPOST MSIP DISTRIBUTION CORRESPONDING TO FIELD MEASURED PIPE CONTRACTION INDICATES THAT THE CRACK REMAINS IN THE COMPRESSIVE REGION

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UT INSPECTIONS CONFIRM THAT CRACK HAS BEEN ARRESTED

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BASED ON MITIGATIONOF CRACK GROWTH, NMPC HAS REASSESSED ITS COMMITMENTTO REPLACE THE SAFE END EXTENSION

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PROPOSING INSPECTION OF FLAW AT THE NEXT OUTAGE

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IF DEPTH C.41T AND LENGTH <.113L, THEN NO FURTHER ACTION

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IF DEPTH ).41T OR LENGTH ).113L, PROVIDE OVERLAYTO THE PIPE

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WELD OVERLAYIS AN ACCEPTABLE ALTERNATIVETO REPLACEMENT Page 21

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June 21, 1993 flaw reveals growth in length or depth.

No repair would be performed if the examination shows no increase in length or depth.

NHPC indicated that a

written submittal for the staff's consideration would likely be forwarded in 3 to 4 weeks.

Original signed by:

Enclosures:

1.

List of Attendees 2.

Licensee Handout Haterial cc w/enclosures:

See next page Distribution:

w/handouts:

Docket File NRC 8, Local PDRs PDI-1 Reading CCowgill, RGN-I JHenning w/o handouts:

T. Hurley/F. Hiraglia, 12/G/18 J. Partlow, 12/G/18 S.

Varga J.

Calvo R. A. Capra J.

Henning C.

Vogan OGC John E. Henning, Project Hanager Project Directorate I-1 Division of Reactor Projects I/II Office of Nuclear Reactor Regulation E. Jordan, HNBB 3701 J. Strosnider, 7/D/4 R. Hermann, 7/D/4 W. Koo, 7/D/4 R. HcBrearty, RGN-I ACRS (10)

V. HcCree, EDO, 17/G/21 C. Cowgill, RGN-I LA:PDI-1 CVo an 0 93 PH: PDI-1 JNennin Wm 4l 93 D: PDI-1 RACa ra ~

2/

93 FFICIAL RECORD COPY Document Name:

NM250410.HTS

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