ML20151Y280

Second Interval Inservice Insp Program,Cooper Nuclear Station, Technical Evaluation Rept

ML20151Y280
Person / Time
Site:	Cooper
Issue date:	09/30/1985
From:	SCIENCE APPLICATIONS INTERNATIONAL CORP. (FORMERLY
To:	NRC
Shared Package
ML20151Y247	List: ML20151Y243 ML20151Y254 ML20151Y280
References
CON-NRC-03-83-096, CON-NRC-3-83-96 SAIC-84-1660, TAC-54588, NUDOCS 8602120639
Download: ML20151Y280 (24)

Text

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Report b. SAIC-84/1660  ;

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I TECHNICAL EVALUATION REPORT SECOND INTERVAL INSERVICE INSPECTION PROGRAM l l COOPER MJCLEAR STATION , {

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t Submf tted to U.S. % clear Regulatory Commission f' Contract No, MIC-03-83-0%

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Subnritted by Science Appitcations International Corporation l .' Idaho Falls, Idaho (

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0602120639 (160127 1

PDR ADOCK 00000290 ,

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CONTENTS 1

g I NTRO D U CT IO N . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3 I. CLASS 1 COMP 0NENTS ......................

3 A. Reactor Vessel ........................

1. Relief Request RI-06, Inaccessible Reactor

{ Pressure Vessel Welds, Category B-A, Items 81.11, 3

Bl .12, Bl . 21, and 81. 2 2 . . . . . . . . . . . . . . . . .

2. Relief Request RI-03, Reactor Pressure Vessel Top Head Nozzle Inner Radli, Category B-D, 8

g I te m B 3.10 0 . . . . . . . . . . . . . . . . . . . . . . . .

B. Pressurizer (Does not apply to BWRs)

C. Heat Exchangers and Steam G?nerators (ib relief requests) 10 g D. Piping Pressure Boundary ..... ............

1. Relief Request RI-01, Circumferential Weld in Containment Penetra tion Assently, Ca tegory B-J, 10 Item B9.11 . . . . . . . . . . . . . . . . . . . . . . . . .

g E. Pump Pressure Boundary (ib relicf requests)

F. Valve Pressure Boundary (fb relief requests) 13 II. CLASS 2 COMPONENTS ......................

A. Pressure Vessels and Heat Exchangers ....... 13 g

1. Relief Request RI-05, Inaccessible Welds on the Residual Heat Removal Heat Exchanger, Ca tegory C-A, Item C1.30 ................. 13 15 fg B. Piping ............................

1. Relief Request RI-02, Residual Heat Removal Drpell Spray Inside Drpell, Category C-F, 15 Items C5.10 and C5. 20 . . . . . . . . . . . . . . . . . . .

2. Relief Request RI-04, Inaccessible Weld lg in Floor Penetration, Category C-F,

! Item C5.11 ........................ 18 C. Pumps ( Pb rellef requests) lE D. Valves (Pb relief requests)

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• III. CLASS 3 COMPONENTS (No relief requests) i

f IV. PRESSURE TESTS (No relief requests)

V. GENERAL ( No relief requests) i e

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j. I R EF ER E N CES . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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TECHNICAL EVALUATION REPORT SECOND INTERVAL INSERVICE INSPECTION PR0(RAM jt COOPER NUCLEAR STATION f INTRODUCTION This report evaluates requests for relief from Section XI of the American Society of Mechanical Engineers ( ASiE) Boiler and Pressure Vessel Code

• by the licensee, Nebraska Public Power District (NPPD), for the Cooper kclear Station, Unit 1 (Cf6-1). The relief requests coverThe the requests O second 120-month inspection interval starting July 1,1984.

are based upon the 1980 Edition of Section XI, with addenda through the Winter of 1981, as spect fled in the applicable revision of 10 CFR 50.55a.

The rest of this introduction summarizes (a) the scope of this report, (b) the previous review of rp j ef requests by Science Applications Inter-O national Corporation (SAIC),L J and (c) the history of CNS-1 since the earlier review.

4 The current revision to 10 CFR 50.55a requires that Inservice Inspection i

(ISI) programs be updated each 120 months to meet the requirements' of newer editions of Section XI. Specifically, each program is to meet the require-I C ments (to the extent practical) of the edition and addenda of the Code j incorporated in the regulation by reference in paragraph (b) 12 months prior to the start of the current 120-month interval.

The regulation recognizes that the requirements of the later editions F

and addenda of the Code might not be practical to implement at facilities

G because of limitations of design, geometry, and materials of construction of components and systems. It, therefore, permits exceptions to impractical examination or testing requirements to be evaluated. Relief from these requirements can be granted provided the health and safety of the public are not endangered, giving due consideration to the burden placed on the licensee if the requirements were imposed. This report only evaluates

% requests for relief dealing with inservice examinations of components and with system pressure tests. Inservice test programs for pumps and valves (IST programs) are being evaluated separately.

Finally,Section XI of the Code provides for certain components and

systems to be exempted from its requirements. In some instances, these

'$, exemptions are not acceptable to the Wclear Regulation Commission (IRC)

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• Hereinafter referred to asSection XI or Code.

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or are only acceptable with restrictions. As appropriate, these instances are also discussed in this report.

f In its previous report dated July 13,1982, SAICII) evaluated relief requests for CNS-1 covering the last 80 months of the first 120-month inter-val that ended July 1,1984. These requests were based on the 1974 Edition

• of the Code with addenda through Summer 1975. The applicable Code and interval were in accordance with the revision of 10 CFR 50.55a in effect On May 19,1983, the EC issued its formal Safety Evaluation 4i at that(gme.which included SAIC's report as an appendix.

Report, On March 1,1984 NPPD submitted a new ISI program for the second

+ 120-month in terval .t il The five relief requests contained in this program submittal were based upon the 1980 Edition of Section XI of the Code with addenda through the Winter of 1981. The Code edition and inspection inter-C vals were in accordance with the revision of 10 CFR 50.55a applicable at the time. Two revisions gf interval were submitted.(9,5Jhe ISI program for the second 120-m WC requested additional inf9 rqution, required to evaluate the revised ,

NPPD ISI plan, on July 31,1984. t 6i Ih0 f by submitting additional information!I.g) and a revisedlicensee responded second-interval ISI to th program.1Vi During this exchange, three of the original relief requests

' were withdrawn and four new ones were added. The six pending relief requests contained in Reference 9 are evaluated in this report.

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I. CLASS 1 COMPONENTS f A. Reactor Yessel

1. Relief Request RI-06, Inaccessible Reactor Pressure Vessel Welds, Category B-A, Items Bl .11, Bl .12, Bl .21, and Bl .22

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Code Requirement Items B1.11 and 81.12:

One circumferential and one longitudinal pressure retaining 0 weld in the bel tline region of the reactor pressure vessel must be volumetrically examined in accordance with Figures IWB-2500-1 and

-2 over essentially 100% of the weld length in the second and suc-cessive inspection intervals. Examinations may be performed at or near the end of the interval.

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Items Bl .21 and Bl .22:

l The accessible length of one circumferential and one meridional pressure retaining weld in the reactor pressure vessel head must be volumetrically examined in accordance with Figure IW3-2500-3 in the second and successive inspection intervals. The l:0 bottom head wolds may be examined at or near the end of the i

interval.

Code Relief Request

t Relief is requested from volumetric examination over 100T, of the length of the following welds

l Type Item Coments

{( Weld IfiB-BB-1 Bottom llead Meridional 01.22 l B1.22 l leiB -BB-2 Bottom llead Meridional itiB-BB-3 Bottom llead Meridional 01.22

,i IIMB -BB-4 Bottom f(cad fieridional 01.22 Bottom llead Meridional Bl.22 iiC 1118 5 Bottom llead Meridional 81.22 l

ItiB -BB-6

! 1910-B0-1 Bottom llead Circumferential 01 .21 l

VCB-B A-2 Circumferential Shell B1.11 Bel tline VCD-BB-1 Circumferential Shell 01.11 C B1.11 VCB-BB-3 Circumferential Shell l

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Type item Comments Weld Longitudinal Shell 81.12 Bel tline VLA-BA-1 801 tline Longitudinal Shell 81.12

( VLA-BA-2 VLA-B A-3 Longitudinal Shell 81.12 Bel tline Longitudinal Shell Bl.12 Bel tline VLB-B A-1 Bel t1ine 81.12 VLB -B A-2 Lon91 tudinal Shell 81.12 Bel tline VLB-B A-3 Longitudinal Shell Longitudinal Shell B1.12 VLC-BB-1 VLC-BB-2 Longitudinal Shell Bl.12

( YLC-BB-3 Longitudinal Shell 81.12 l Proposed Alternative Examination

( Visual inspection of all welds during the system hydrostatic test will be conducted.

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Licensee's Basis for Requesting Relief

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The CNS-1 construction permit was issued before the effectivo date of implementation for ASME Section XI and thus the plant was not designed to meet the requirements of inservice inspection; therefore,100% compliance is not feasible or practical.

'( Access to the reactor vessel beltline region is not possible.

The reactor vessel is insulated with permanent reflective insula-tion and surrounded by a concrete biological shield. The annular space between the inside diameter of the insulation and outside There is no diameter of the reactor vessel is a nominal 2 inches.

working space to remove the insulation panels from the vessel,

( which precludes both direct and remote examination of the outside sur face. The interior surface is clad and the vessel internals, shroud, and jet pumps make an internal volumetric examinition of these welds impractical for a meaningful examination.

Parts of longitudinal seams VLA-BA-1, -2, and -3 however, g

appear to be accessibic from openings around the recirculation riser nozzles N2A, N2E, and !!211, respectively. Again, these seams are not 100% accessible. Scanning surface area would require a This surface area is only minimum of 17 inches from weld. When the nozzle-available for a few inches--closest to nozzle.

to-vessel welds (Category B-D) are examined, a best effort

( examination of these longitudinal seams shall be performed.

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Eval uation The licensee has requested relief from volumetric examination of 19 pressure retaining welds in the reactor vessel. Seven of I the welds are circumferential and meridional The welds remaining 12 inwelds the bottom are head under Items Bl.21 and Bl.22.

circumferential and longitudinal welds in the reactor vessel shell under Items Bl .11 and Bl .12. Seven of the 12 shell welds for which relief is requested are in the beltline region.

I Welds 1f4B-80-1 through -6 are bottom head meridional welds which are partially inaccessible. The reactor vessel support skirt limits access to the total length of these welds. The licensee has stated that the accessible portion of these welds (approximately 6 inches of weld length) will be examined on a best effort basis in conjunction with the examination of the support skirt weld I liNC-Cl-1, -2, and -3. Examination of portions of the six meridi-onal head welds will result in examination of a length This total weld total ofshould 36 inches be length of meridional head weld.

a significant fraction of 100% of the length of one meridional head weld. The Code requires that the accessible length (essen-tially 100% of the weld length) of one meridional head weld be f examined in the second and successive inspection intervals (B1.22). The examination of 36 inches of total weld length from six separate welds is an acceptable alternate examination.

Relief is requested from volumetric examination of circum-ferential weld liiD-BB-1 in the bottom head since it is rendered C inaccessible by the vessel support skirt. Item Bl .21 requires that the accessible length of one circumferential head weld be examined in the second and successive inspection intervals. Since weld liiC-BB-1, which is also a circunferential weld in the bottom head, is scheduled to be examined in the second interval, the Code requirement is fulfilled and no relief is required for weld lC

. IIMD-B B -1.

Relief is requested from volumetric examination of 12 longi-tudinal and circumferential shell welds under Items 01.11 and

Bl .12. Items 81.11 and 81.12 require volumetric examination of one circumferential and one longitudinal, weld respectively, in

'I the beltline region during the second and successive inspection

! intervals. Since circunferential shell welds VCB-BB-1 and -3 and

. longitudinal shell welds VLC-BB-1, -2, and -3 are not in the bel t-line region, no examination, and hence no relief, is required.

kcess to the reactor beltline region to inspect circumfor-I ential weld VCB-BA-2 and longi tudinal welds VLA-BA-1, -2, and -3 and VLB-BA-1, -2, and -3 appears to be impractical . The reactor l vessel is insulated with permanent reflective insulation and sur-rounded by a concrete biological shield. The annular space between the inside diameter of the insulation and the outside diameter of the reactor vessel is a nominal 2 inches. There is no working ,

I space to remove the insulation pancis from the vessel, which l

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I lt precludes both direct and remote examination of the outside surface. The interior surface is clad and the vessel internals, l

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shroud, and jet pumps make an internal volumetric examination of f these welds impractical for a meaningful examination.

Parts of the longitudinal seams VLA-BA-1, -2, a id -3 appear

' to be accessible from openings around the recirculation riser nozzles N2A, N2E, and N211, respectively. These welds are only accessible for examination for a few inches adjacent to the noz-f zies. When the nozzle welds (Category B-0) are examined, the accessible portion of these longitudinal welds will be scanned to l the extent possible.

i The reactor vessel is monitored for radiation damage in the beltline region. This program (References NED0-10115 and APED-f 5490, 67A PE2 May 1967, Class I and Station Surveillance Procedure 7.4.9) meets the intent of 10 CFR Part 50, Appendix H. This '

program will provide data to monitor radiation damage to the vessel beltline materials throughout the vessel's service If fe. The vessel was designed and fabricated in accordance with the rules of Section III,1965 Edition of the ASME Boiler and Pressure Yessel

( Code.

The areas of all beltline welds should be inspected visually from the reactor vessel inside surface to the extent practical using a remote television camera during the Inspection required for Categories B-N-1 and 3-N-2.

C To maintain the extent of examination, an alternative  ;'

inservice inspection program of both volumetric and visual exami-nation is needed. Certain longitudinal and circumferential welds, not in the beltline region, are partially or wholly accessible for inservice inspection. The volumetric examination of accessible

't circumferential and longitudinal shell welds could be increased to achieve (1) an examination sample whose total weld length is equal to that required for the Category B-A welds for which relief was ,

requested or (2) 100% of the length of each accessible RPY shell weld, whichever is less. In addition, visual examination for

' gross leakage should be performed during each system pressure test

( in accordance with IWA-5240. Such exaninations should furnish sufficient information to evaluate the structural reliability of the welds since they indicate cracks through the metal.

The CNS-1 151 program indicates that both aspects of the 4

proposed alternative inspections will be carried out. Shell cir-cumferential weld VCB-BB-4 and longitudinal welds VLD-88-1, -2, it and -3 will be volumetrically examined over 100% of their length.

j Longitudinal welds VLC-BD-1, -2, and -3 will be pirtlally examined on a best ef fort basis. All these shell welds are above the beltline region. In addition, the licensee has proposed visual examination during the system hydrostatic test for all the reactor

[t pressure vessel welds.

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Conclusions and Recommendations Based on the above evaluation, it is concluded that for the r

lower head circumferential weld (20-BB-1), for the circumferential shell welds out of the beltline region (VCB-88-1 and -3), and for the longitudinal shell welds out of the beltline region (VLC-BB-1,

-2, and -3) no relief is required and no relief should be granted.

Also based on the above evaluation, it is concluded that for

( the lower head meridional welds and for the circumferential and longitudinal shell welds in the beltline region, the Code re-quirements are impractical . It is further concluded that the alternative examination discussed above will provide the necessary I

added assurance of structural reliability. Therefore, it is recom-mended that relief be granted from volumetric examination of the j

identified welds for the 10-year inspection interval with the

( following provisions:

(a) Partial volumetric examination of the longitudinal shell welds in the beltline region through the recirculation riser nozzle ports and partial volumetric examination of

( the six meridional welds in the bottom head should be conducted on a best effort basis.

(b) Examination of the accessible shell welds out of the beltline region should be increased to achieve (1) an examination sample whose total weld length is equal to that required for the Item Bl.11 and Bl.12 welds for

.t which relief was requested or (2) 1007, of the length of each accessible shell weld, whichever is less.

(c) the beltline region weld areas should be visually examined from the vessel interior during the exami-nations required under Categories B-N-1 and B-N-2.

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(d) General visual examinations per IWA-5240 should be made during each system pressure test for evidence of leakage in the areas of the lower head and the shield annulus

below the vessel.

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References i References 1, 8, and 9.

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2. Relief Request RI-03, Reactor Pressure Vessel Top Head bzzle l

l Inner Radii, Category 8-0, Item B3.100 lt L Code Requirement The extent of the volumetric examination of each nozzle shall cover 100% of the volume to be inspected as shown in Figure IWB-f 2500-7(a) through (d), which includes the primary nozzle-to-vessel welds and inside radiused sections. All nozzles shall be examined during each inspection interval. At least 25% but not more than 50% (credited) of the nozzles shall be examined by the end of the first inspection period and the remainder by the end of the inspection interval.

C Code Relief Request I Relief is requested from the volumetric examination of the

( nozzle inner radius (NIR) for the following nozzles on the reactor pressure vessel (RPV) closure head:

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N6A NIR Head Spray Nozzle i N6B NIR Instrumentation Nazzle N7 NIR Head Vent Nozzle C

Proposed Al ternative Examination Surface examinaticiof the inner radius of the three identi-( fled nozzles will be performed.

Licensee's Basis for Requesting Relief

't During refueling activities, the RPV closure head is removed allowing access to RPV closure head NIR. A surface examination is more sensitive in detecting surface defects at the NIR than the volumetric examination performed from the outside surface.

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Evaluatten Volumetric examination of the norzle-to-vessel weld is  ;

required and would be performed ultrasonically, independently of the NIR examination. Because of the geometry of the joint, ultra-

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sonic examination of the.NIR sections is not feasible. If the entire joint were radiographed, an extra set of exposures would i

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be required for the NIR sections. The proposed surface exami-nation, however, would be more sensitive than a volumetric examination in detecting surface defects at the NIR since the g surface is not clad. In addition, surface examination of the NIR at the three nozzles as proposed for the alternative examination would result in less radiation exposure to personnel than the volumetric examination.

Conclusions and Recommendations Based on the above evaluation, it is concluded that for the It areas discussed above, the Code requirements are impractical.

is further concluded that the alternative examination discussed above will provide the necessary added assurance of structural

.p reliability. Therefore, the following is recommended:

Relief should be granted from the volumetric examination of the nozzle inner radius of the three identified nozzles during the inspection interval provided that the proposed alternative surface examination is carried out.

g References References 1, 6, 7, and 9.

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! D. Pressurizer

. Does not apply to BWRs.

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l C. Heat Exchangers and Steam Generators

g No relief requests.

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f D. Piping Pressure Boundary g 1. Relief Request RI-01, Circumferential Weld in Containment Penetration Assenbly, Category B-J, Item B9.11 Code Requirement For cireve rential welds with nominal pipe size 4 inches and greater, surfact. plus volumetric examinations in accordance with Figure IWB-2500-8 shall be performed during each inspection inter-val on essentially 100% of the weld. The examination shall include the following:

(a) All terminal ends in each pipe or branch run connected to vessels.

(b) All terminal ends and joints in each pipe or branch run connected to other components where the stress levels exceed p the fn110 wing limits under loads associated with specific sef sna events and operational conditions:

(1 ) primary plus secondary stress intensity range of 2.4Sm for ferritic steel and austenitic steel, and

g ( 2) cumulative usage factor U of 0.4.

(c) All dissimilar metal welds between conbinations of (1 ) carbon or low alloy steels to high alloy steels, g ( 2) carbon or 1ow alloy steels to high nickel alloys, and (3) high alloy steels to high nickel alloys. j (d) Additional piping welds so that the total equals 25% of the circumferential joints in the reactor coolant piping system.

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This total does not include welds excluded by IWB-1220.  !

I These additional welds may be located in one loop (one loop is currently defined for both PWR and BWR plants in the 1980 i Edi tion ).

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!g For welds in carbon or low alloy steels, only those welds showing reportable preservice transverse indications need be examined for transverse reflectors.

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Code Relief Request Relief is requested from volumetric and surface examination f of one pressure-retaining piping weld in each of 15 primary con-tainment penetration assemblies as follows:

Description Inaccessible Weld Core Spray Loop A CSA-BJ-25 Core Spray Loop B CSB-BJ-25 C CWA-BJ-27A Reactor Water Cleanup Feedwater Loop A FWA-BJ-35 Feedwater Loop B FWD-BJ-34 Main Steam Loop A MSA-BJ-43 Main Steam Loop B MSB -BJ-39 Main Steam Loop C MSC-BJ-43

!0 MSD-BJ-47 Main Steam Loop D HPCI Steam PSA-BJ-22 RHR 20-Inch Supply RHA-BJ-30A RHR Loop A RHB-BJ-28A RHR Loop B RHC-BJ-24 RHR 6-Inch Head Spray RHD-BJ-31 0 RSA-BJ-13A RCIC Steam Proposed Alternative Examination

.C A visual inspection for evidence of leakage will be conducted during the system hydrostatic pressure test of IWB-5000.

Licensee's Basis for Requesting Relief l(!

Due to its design, the primary containment penetration assembly leaves one pressure-retaining piping weld inaccessible for examination by either surface or volumetric methods.

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Evaluation The identified welds are completely inaccessible for volu-metric or surface examinatt'on because the welds are located inside a containment penetration. Each primary containment penetration jt assembly, due to its design, leaves one press tre-retaining piping weld inaccessible for examination by either surface or volumetric means. The welds can anly be examined by inspecting for evidence of leakage during syskm hydrostatic pressure tests.

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f.' The initial design of the assemblies did not provide for accessibility for inservice examinations. If, however, the work-manship and quality assurance of the welding as well as the preservice examinations are assumed adequate, then an examination of the first pressure boundary weld either upstream o* downstream g

of the inaccessible weld should reflect service-indv"d failures for that particular piping section. Thus, the fin % (Ressure boundary weld adjacent to the inaccessible weld on each of these process pipes should be volumetrically examined, where practical, over 100% of its length during each inspection interval. Such an examination would maintain sample size. The licensee should also 7 conduct visual examinations at these penetrations, as proposed, which would indicate any cracks through the metal, Conclusions and Recommendations g.

Based on the above evaluation, it is concluded that for the welds discussed above, the Code requirements are impractical. It is further concluded that the alternative examination discussed above will provide necessary added assurance of structural reli-ability. Therefore, it is recommended that relief be granted from I the volumetric examination of the identified welds, with the following provisions:

(a) The first accessible pressure boundary weld either up-stream or downstream of the inaccessible weld on' each of these process pipes should be examined by volumetric and O surface methods, where practical, over 100% of its length during each inspection interval.

(b) The proposed visual examinations should be performed on the containment penetration assemblies when leakage and t hydrostatic tests are conducted in accordance with IWA-

!- f 5000.

References C References 1, 6, 7, and 8.

E. Pump Pressure Boundary g

No relief Requests.  !

F. Valve Pressure Boundary l 0 No relief requests.

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II. CLASS 2 COMP 0ENTS A. Pressure Vessels and Heat Exchangers i

1. Relief Request RI-05, Inaccessible Welds on the Residual Heat Removal Heat Exchanger, Category C-A, Item C1.30 t

Code Requirement Pressure retaining tubesheet-to-shell welds must be volu-metrica11y examined over essentially 100% of the weld length in accordance with Figure IWC-2500-2 each inspection interval.

't Code Relief Request Relief is requested from volumetric examination of the tube-t ( sheet-to-shell welds (RHR-CA-5A and Rm-CA-5B) on the RHR heat exchanger, i

i Proposed Alternative Examination

.g A visual examination of the welds will be conducted during the system leakage test.

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g Licensee's Basis for Requesting Relief The weld joint configuration is not accessible for volumetric examina tion. Limited access also precludes a surface examination, therefore, a visual inspection of the area during a system leakage

test will in performed each inspection interval.

>,6 Evaluation The tubesheet-to-shell weld on the Rm heat exchanger is a

O complex configuration involving two partial penetration welds and a fillet weld. Access to the weld is extremely limited as 7.

result of the configuration. Both volumetric and surface examl-nation are essentially prohibited by the limited access. Visual examination of the weld during system pressure tests should provide adequate assurance of structural reliability since it would provide initial evidence of seepage from a through-wall je perforation.

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Conclusions and Recommendations I Based on the above evaluation, it is concluded that for theIt welds discussed above, the Code requirements are impractical.

is further concluded that the alternative examination discussed above will provide necessary added assurance of structural reli-abili ty. Therefore, the following is recommended:

I Relief should be granted from performing volumetric examina-tion of identified welds provided that visual examination of the welds for leakage is performed during periodic hydrostatic testing in accordance with IWC-5000.

O Re ferences Reference 9.

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B. Piping  ;

1. Relief Request RI-02, Residual Heat Removal Drywell Spray Inside Drywell , Category C-F, Items C5.10 and C5.20 (Items C2.1 and C2.2

.g in 1974 S75)

Code Requirement l

.I 74S75, Category C-F, Items C2.1 and C2.2:

The following pressure-retaining weld areas in piping, pumps, and valves in systems circulating reactor coolant shall be volu-metrically examined over 100% of their lengths:

f (a) circumferential Sutt welds at structural discontinuities (b) circumferential butt welds in piping within 3 pipe diameters of the centerline of rigid pipe anchors, or anchors at the penetration of the primary reactor containment, or at rigidly anchored components g.

(c) longitudinal weld joints in pipe fittings (i.e., in tees, elbows, reducers)

(d) pump casing and valve body weld joints.

I This includes the weld metal and base metal for one wall thickness beyond the edge of the weld.

80W81, Category C-F:

!I For circumferential and longitudinal welds with a nominal

! wall thickness less than or equal to 1/2 inch, a surface examina-tion in accordance with Figure IWC-2500-7 is required over 100% of the weld length each interval (C5.10). For longitudinal welds in the same thickness piping, 2.St at the interesecting circumferen-tial weld shall be examined by surface methods each interval.

g For circumferential and longitudinal welds with a nominal

.i wall thickness greater than 1/2 inch, a volumetric and surface examination in accordance with IWC-2500-7 is required over 100% of

-I the weld length each interval (C5.20). For longitudinal welds in the same thickness piping, 2.5t at the intersecting circumferential

!g weld shall be examined by volumetric and surface methods each

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Code Relief Request i

Relief from surface and volumetric examination of the RHR f drywell spray welds inside the drywell is requested.

Proposed Alternative Examination 1 A visual examination shall be performed during a system

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pneumatic test in accordance with CNS Technical Specifications Licensee's Basis for Requesting Relief

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These welds are located inside the drywell and do not They see the inerted normally contain water; they are empty.The welds receive minimum inservice environment during operation.

stress, and a surface or volumetric examination would not signi-f ficantly increase quality or safety. To impose the Code require-ments would result in an overall increase in man-rem exposure without commensurate increase in safety, i

C Evaluation 10 CFR 50.55a(b)(2)(iv)( A), as adopted in 44 FR 57912, states the following:

(iv) Pressure-retaining welds in ASME Code Class 2, piping (applies to Tables IWC-2520 or IWC-2520-1, Ca tegory C-F).

- () ( A) Appropriate Code Class 2 piping welds in Residual Heat l

Removal Systems, Emergency Core Cooling Systems, and Con-tainment Heat Removal Systems shall be examined. .The extent l l of examination for these systems shall be determined by the 1 -

requirements of paragraph IWC-1220, Table IWC-2520, Categories

(; C-F and C-G, and paragraph IWC-2411 in the 1974 Edition, Summer 1975 Addenda, of Section XI of the ASME Code.

Clearly, the intent of the Regulation is that a representative 4

sample of welds in these systems be examined and relief should not be ranted from examining the welds in the RHR drywell spray system i

The basis for relief provided by the licensee does not firmly

!; establish that implementation of the subject weld examinations is

, 3

! impractical. The drywell radiation level has not beenThe stated nor proposed has the cumulative dose to personnel been estimated. .

l alternative examination, " visual examination during a system pneu-

$ matic test" say in fact, be _ impractical.

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Conclusions and Recommendations I Based on the above evaluation, it is concluded that for the welds discussed above, adherence to the Code requirements is not impractical. It is further concluded that the alternate test proposed may be impractical. Therefore, relief should not be granted.

'f References Reference 9.

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2. Relief Request RI-04, Inaccessible Weld in Floor Penetration, Category C-F, Item C5.11 (Item C2.1 in 1974 S75) ,

f Code Requirement 74S75, Category C-F, Item C2.1:

( The following pressure-retaining weld areas in piping, pumps, and valves in systems circulating reactor coolant shall be volu-metrica11y examined over 100% of their lengths:

(a) circumferential butt welds at structural discontinuities

' O (b) circumferential butt welds in piping within 3 pipe diameters of the centerline of rigid pipe anchors, or anchors at the penetration of the primary reactor containment, or at rigidly anchored components g (c) pump casing and valve body weld joints.

This includes the weld metal and base metal for one wall thickness beyond the edge of the weld.

p 80W81, Category C-F

For circumferential welds with a nominal wall thickness less than or equal to 1/2 inch, surface examination in accordance with Figure IWC-2500-7 is required over 100% of the weld length each

. interval.

!O Code Relief Request i

g Relief from surface examination of weld Rl0-CF-9 is requested.

proposed Alternative Examination

!g A visual inspection for evidence of leakage will be conducted

! during the system hydrotest of IWC-5000.

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Licensee's Basis for Requesting Relief The location of this weld inside the floor penetration makes it inaccessible for volumetric or surface examination.

t Evaluation The weld for which relief is requested is located in the f 6-inch RIR Head Spray Vent System. There are at least seven other Class 2 Category C-F welds in this system schedu1ed for examina-tion during the second inspection interval.

Because of its inaccessible location, the weld cannot be examined by volumetric or surface methods. Visual examination O could, however, be performed during system leakage and hydro-static tests, which would provide initial evidence of seepage from a through-wall perforation.

O Conclusions and Recommendations Based on the above evaluation, it is concluded that for the weld discussed above, the Code requirements are impractical. It is further concluded that the alternative examination discussed above will provide necessary added assurance of structural reli-

O ability. Therefore, the following is recommended

Code relief from the volumetric examination of the identified weld should be granted provided that visual examinations are per-formed during system hydrostatic pressure tests in accordance with IWC-5000.

$C References References 1 and 9.

.G C. Pumps i No relief requests.

D. Valves lf j No relief requests.

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III. CLASS 3 COMPONENTS 2 relief requests.

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IV. PRESSURE TESTS IC No relief requests.

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1 No relief requests.

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REFERENCES

1. Science Applications, Inc., Cooper Nuclear Station, Inservice Inspec-( tion Program, Technical Evaluation Report, SAI Report No.

186-028-04, July 13,1982.

2. D. B. Vassallo (NRC) to J. M. Pflant (NPPD), Safety Evaluation Report, Phy 19,1983.

i 3. J. H. Pilant (NPPD) to D. B. Yassallo (NRC), Cooper Nuclear Station Second Ten-Year Inservice Inspection Plan, March 1,1984.

4. J. D. Weaver (NPPD) to E. D. Sylvester ( MIC), Cooper NJclear Station Second 10-Year In-Service Inspection (ISI) Program, June 15, 1984.

'(

5. J. D. Weaver (NPPD) to E. D. Sylvester ( NRJ), Cooper hbclear Station Second 10-Year In-service Inspection (ISI) Program, July 25, 1984.

6. Request for Additional Information, July 31, 1984.

7. J. D. Weaver (NPPD) to E. D. Sylvester (NRC), Coopec Nuclear Station g Second 10-Year In-Service Inspection (ISI) Program; Additional Infor-mation, Septerrber 19, 1984.

8. J. D. Weaver (NPPD) to E. D. Sylvester (NRC), Cooper Nuclear Station Second 10-Year In-Service Inspection (ISI) Program, December 18, 1984.

Ib 9. J. M. P11 ant (NPPD) to D. B. Vassallo ( NRC), Cooper hbclear Station Second 10-Year In-Service Inspection (ISI) Program, March 15, 1985.

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