ML20237A738

Requests Response to Encl Request for Addl Info Re Inservice Insp Program within 60 Days of Receipt of Ltr

ML20237A738
Person / Time
Site:	Millstone
Issue date:	12/09/1987
From:	Jaffe D Office of Nuclear Reactor Regulation
To:	Mroczka E NORTHEAST NUCLEAR ENERGY CO.
References
NUDOCS 8712150209
Download: ML20237A738 (9)

Text

December 9,1987 Docket No. 50-336 t'r. Edward J. Mroczka Senior Vice President )

Nuclear Engineering and Operations Northeast Nuclear Energy Cortpany P. O. Box 270 Hartford, Connecticut 06141-0270

SUBJECT:

MILLSTONE NUCLEAR POWER STA110N, UNIT NO. 2 INSERVICE INSPEC110N (TAC NO. 59265) i We are in the process of reviewing the Inservice Inspection Program for Millstone Unit 2. In order that we tray ccrnplete our review, we request that you respond to the enclosed request for additional information within 60 days following re-ceipt of this letter.

The reporting and/or recordkeeping requirements contained in this letter affect fewer than 10 respcodents; therefore, Cf'B clearance is not required under P. L.96-511.

Sincerely gm (M'7 Eff' David H. Jaffe, Project Manager Project Directorate I-4 Division of Reactor Projects I/II  ;

Enclosure:

Request for Additional Information cc: Plant Service List I

Distribution; m

,; Docket Eile. NRC & Local PDRs PDI-4 Reading S. Varga B. Boger S. Norris D. Jeffe R. Ferguson J. Stolz OGC-Bethesda E. Jordan J. Particw ACRS (10) [ Gray File] j LAP I-4 PDI-4 ' ' . j' PD SN 1s DJaffe y JSt Iz 12/ 7 /87 12/%/87 ( 12/ /87

$712150209871209 R

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PDR i

Mr. Edward J. Mroczka Millstone Nuclear Power Station Northeast Nuclear Energy Company Unit No. 2 cc:

Gerald Garfield, Esq. Mr. Wayne D. Romberg Day, Berry & Howard Superintendent Counselors at Law Millstone Nuclear Power Station City Place P. O. Box 128 Hartford, Connecticut 06103-3499 Waterford, Connecticut 06385 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 1 Office of Executive Director for Operations 631 Park Avenue King of Prussia, Pennsylvania 19406 Mr. Charles Brinkman, Manager Washington Nuclear Operations C-E Power Systems 4 Combustion Engineering, Inc. - '

7910 Woodmont Avenue Bethesda, Maryland 20814 Mr. Lawrence Bettencourt, First Selectman Town of Waterford Hall of Records - 200 Boston Post Road Waterford, Connecticut 06385 Northeast Utilities Service Company ATTN: Mr. Richard R. Laudenat, Manager Generation Facilities Licensing Post Office Box 270 Hartford, Connecticut 06141-0270 Kevin McCarthy, Director Radiation Control Unit i Department of Environmental Protection State Office Building Hartford, Connecticut 06106 Mr. Theodore Rebelowski U.S. NRC P. O. Box 615 Waterford, Connecticut 06385-0615 Office of Policy & Management ATTN: Under Secretary Energy Division .

80 Washington Street l Hartford, Connecticut 06106 '

REQUEST FOR ADDITIONAL INFORMATION Millstone Unit 2 INSERVICE INSPECTION PROGRAM Your letter dated December 23,1986(1) submitted a revised inservice inspection (ISI) and inservice testing (IST) program, and relief requests for i the second 10-year inspection interval of Millstone Unit 2. This submittal l also included additional information in response to our specific questions transmitted in Reference 2.

A review of the necember 23, 1986 submittal indicates that certain  ;

detailed information necessary for the NRC to review and approve the ISI plan has still not been incorporated into the MP-2 ISI program documentation. The following questions and comments address tne areas where additional detail and clarification are required.

GENERAL COMMENT

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1. In the MP-2 plan, many procedures are specified, others are referenced as "special", and some have been left blank, giving no reference. While the review of examination procedures is a Region function, they should be specified in the plan for completeness and as a reference for the Regional Office. Please describe all "special" procedures and reference all other procedures. For procedures that have not been finalized, please providt both a reference and an estimated date for final completion. '

2. In addition to providing the basis for the extent of the examination sample, the ASME Code provides guidelines for implementing the inspec-tions during each 10-year interval . Please provide an overall narrative description of the method used to meet the requirements of Sections IWB-2412, IWC-2412, IWB-2420, IWC-2420, and IWF-2420 for each examination category. (See paragraphs 8,13a, and 14 for additional discussion.)

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l SPECIFIC COMMENTS INTRODUCTION - Paragraphs 1.0 and 1.3 ,

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3. Paragraph 1.0 of the Introduction states that the applicable code for developing the MP-2 ISI program is the ASME Boiler and Pressure Vessel  ;

Code,Section XI, 1980 Edition with addenda through Winter 1981 Addenda l (ASME 80W81). Paragraph 1.3 of the Introduction states that ASME 74S75 will continue to be used for extent of examination of Class 1, Category B-J and Class 2, Category C-F and C-G pipe welds. l Please list any ASME Code cases that have been applied in developing the MP-2 ISI plan in conjunction with the stated codes and describe specifi-cally where and how the code cases have been applied.

APPLICABLE ASME SECTION XI EXEMPTIONS EMPLOYED AT MILLSTONE UNIT 2

4. This section restates the paragraphs from ASME 80W81 which relate to exemptions with very few references to specific applications at MP-2.

The section also acknowledges that the exemptions stated in IWC-1220, Table IWC-2520, Categories C-F and C-G, and paragraph IWC-2411 in ASME 74S75 will be applied. The application of the stated and implied exemptions to development of the MP-2 ISI program should be clarified and documented in the plan. For example, the system classification diagrams given in Section 3.0 include a much broader range of piping and systems within Class 1 and 2 than is scheduled for inspection in sections 4.0 and 5.0. Presumably, many piping systems, subsystems, and components were exempted from inspection through application of Code exemptions.

Please provide a listing of systems, subsystems, components, or zones exempted from inspection for each class because the sample of welds selected for examination cannot be determined without this information.

Also, please provide supporting information to explain each exemption '

based on Code requirements.

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l SECTION 4.0 - ISI PROGRAM CLASS 1 COMPONENTS Cateaory B-A (Shell and Bottom Head Welds in Reactor Vessel)

5. This section lists the 20 reactor vessel shell and bottom head welds in Category B-A "for information" but does not specify which welds will be examined in the second interval. Please state specifically which Category B-A reactor vessel shell and bottom head welds (including code item number) will be examined during the second interval to meet the requirements in Table IWB-2500-1 of ASME 80W81. i l

Cateaory B-A (Welds in RV Head)

6. This section lists the eight reactor vessel head welds in Category B-A "for information" but does not specify which welds will be examined in the second interval. Please state specifically which reactor vessel head I welds (including code item number) will be examined during the second interval to meet the requirements in Table IWB-2500-1 of ASME 80W81.

Cateaory B-B (Welds in Steam Generators - Primary Side)

7. The note indicated by " * " in this section of the MP-2 ISI plan states that the " code does not consider Combustion Engineering (C-E) design steam generators with tubesheet-to-tubesheet extension weld." The Examination Requirements for Category B-B, Item B2.40, Tubesheet-to-Head )

Weld, are shown in Figure IWB 2500-6 of ASME 80W81. Design A in this figure is representative of the C-E steam generator design and shows that the required examination volume (ABCD) includes the circumferential weld on each side of the extension ring and any meridional welds in the extension ring. Accordingly, circumferential welds BHC-2 and BHC-3 as well as meridional welds in the extension ring (BHV-1, 3, 5, 7) are all included in the examination volume for Item B2.40.

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' 8 Unless there is additional technical information to support your con-clusion that the weld is exempt from examination, please respecify the examination of the steam generator primary side to meet the requirements of Category B-B of the Code; i.e., in addition to the tubesheet weld area, the scheduled examinations must also include (a) a circumferential weld in the SG head such as BHC-1 (stay cylinder base to hemisphere) and (b) a meridional head weld, such as BHM-3 already scheduled.

Cateaory B-F (Dissimilar Metal Welds) 1

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8. Of the 28 Category B-F welds scheduled for examination, almost 30% are being examined in a different period of the secono inspection interval The ASME Code requires, within the

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than they were in the first interva..

limits of practicality (IWB-2420), that examination sequences established in the first interval be maintained in subsequent intervals such that the time interval between repeated inspections from inspection interval to inspection interval is approximately ten years.

Please provide justification for the significant changes in the sequence of Category B-F examinations in the second interval.

Cateaory B-J (Pressure Retaining Welds in Piping)

9. The plan indicates that ASME 74S75 is being used to determine the extent of examination of Class 1 pipe we'ds in accordance with 10 CFR 50.55a(b)

(2)(ii). ASME 74S75 requires that the extent of examinations performed each interval include (i) 25% of circumferential joints (including any adjoining 1-ft sections of longitudinal welds) and (ii) 25% of the pipe branch connection joints. Longitudinal welds covered under Items B9.12 and B9.22 are required '.n be examined only if the longitudinal weld intersects a circumfered bl weld to be examined under Items B9.11 and 89.21. The longitudinal welds are not to be included in the calculation of the percentage of welds examined.

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(e) The plan indicates that 64 Class 1, Category B-J, circumferential welds will be examined during the second interval. In RR#3, relief is requested in the examination of 29 of these welds. Please explain the method used to select the Category B-J welds in order to minimize the number of welds for which relief is requested.

Cateaory B-K-1 (Integral Attachments for Piping, Pumps, and Valves)

10. The only items in Category B-K-1 of the MP-2 plan are the 16 welded attachments to the primary coolant pumps. C-E plant designs have included welded attachments to Class 1 piping, such as safety injection piping, that are covered by Category B-K-1 requirements. Please confirm that all items in this category have been listed.

Cateaory B-P (System Pressure Tests for all Class 1 Components)

11. The only items identified for examination under Category B-P in the component listing of Section 4.2 are the pressurizer nozzles in Item B15.20 (system leakage on the pressure retaining boundary of the pres-surizer). Please provide a description of other itens to be examined under Category B-P.

SECTION 5.0 - ISI PROGRAM CLASS 2 COMP 0NENTS l

Cateaory C-A (Pressure Retaining Welds in Pressure Vessels)

12. Weld 2-SC-1A is listed as an Item C1.20 head circumferential weld in Section 5.1 under steam generators. This weld is not included on the component list in Section 5.2 nor is it shown on the drawing in Section 5.3. Please clarify the wela designation 2-SC-1A and its location.

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Cateaory C-B (Pressure Retaining Nozzle Welds in Vessels) 13(a) Note 3 of Table IWC-2500-1 under Category C-B requires that the nozzles selected initially for examination be examined over the service lifetime of the component. One feedwater nozzle on SG #1 and one main steam nozzle on SG #2 were examined during the first interval. For the second interval, examination of both nozzles on  :

SG #2 is proposed. Please explain why MS-1 on SG #1 has been selected rather than MS-1 on SG #2. ,

1 13(b) The Code requires that nozzle welds included under Item C2.20 must be examined with both surface and volumetric methods. Only surface examination appears to be scheduled for the nozzle welds of the Shutdown Heat Exchangers. Please explain the reason that both the surface and volumetric examinations are not included.

Catecory C-C (Integral Attachments for Vessel Piping, Pumps, and Valves)

14. In reviewing Category C-C of the plan, some differences have been iden-tified between the zone drawing, the examination sample (Section 5.1),

and the component list (Settion 5.2). For example, Component No. 312012 is listed for examination in the first period of the second interval in Section 5.1, but this component is not listed in Section 5.2. Component No. 307009 is listed in Sections 5.1 and 5.2 under Item C3.20 (integ-rally welded piping attachment), but Drawing 25203-20160 for Zone 2-15 does not indicate that 307009 is an integrally welded attachment.

Several welded attachments to the piping, such as 404024, 407005, 507001, 504001, 304029, 312016, 4120166, 412009, and 412003 are shown on the zone isometric drawings for Zones 2-15 and 2-16, but are not included in either the examination sample in Section 5.1 or in the component list in Section 5.2.

Please clarify the specification and selection of the examination sample under Category C-C. Please explain the basis for not including in the 7

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. j component listing (Section 5.2) or in the examination sample (5.1) all welded attachments to the pressure boundary, as identified in the zone drawings.

Categories C-F and CF/CG (Pressure Retaining Welds in Piping) l

15. The plan indicates that 74S75 is being used to determine the extent of examination for Categories C-F and C-G in all Class 2 piping. The l information required to complete the review is essentially the same as i described for Category B-J in Paragraph 9 above. Please provide the same general information as requested in (a), (b), and (c) of Paragraph 9.

SECTION 7.0 - COMPONENT SUPPORTS Cateaory IWF (Component Supports)

16. The ISI Program includes a selection and schedule for 578 component support examinations, including 115 Class 1 supports, 96 Class 2 supports, and 367 Class 3 supports. The supports have not been classified according to Code Category F-A, F-B, and F-C.

(a) Please revise the component listing (Section 7.3) to include i

Category and Item No.

(b) Please provide a brief narrative of the basic concepts used for determining the examination sample, including the application of exemption criteria. I References

1. E. J. Mroczka (NNECo) to A. C. Thadani (NRC), December 23, 1986; response to request for additional information, revised inservice inspection l report attached. l

2. D. H. Jaffe (NRC) to J. F. Opeka (NNECo), July 29, 1986; request for additional information on the inservice inspection program.

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