ML20092M215
| ML20092M215 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 09/25/1995 |
| From: | Hunger G PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9509290131 | |
| Download: ML20092M215 (17) | |
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,' - 10CFR50.55a(3)(1)
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PECO ENERGY nce c-eev Nuclear Group Headquarters 965 Chestertxook Boulevard Wayne. PA 19087 5091 September 25,1995 Docket No. 50-352 50-353 License No. NPF-39 NPF-85 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
Subject:
Limerick Generating Station Units 1 and 2 Inservice Inspection, inservice Testing, and Repair and Replacement Programs - Supplemental Information Supporting Basis for Continued Use of the 1986 Edition of the ASME Section XI Code Requirements Gentlemen:
By letter dated April 27,1995, PECO Energy Company submitted a request proposing an alternative to updating the Inservice inspection (ISI), inservice Testing (IST), and Repair and Replacement Programs to the latest edition of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code for Limerick Generating Station (LGS), Unit 1, following the completion of the Rrst Ten-Year Inspection Interval cs required by 10CFR50.Sfs(g)(4)(ii). Specifically, we requested an altamative to the requirements of 10CFR50.55s(g)(4)(li) which stipulates that: " Inservice examination of components and system pressure tests conducted during successive 120-month inspection intervals must comply with the requirements of the latest edition and addenda of the Code incorporated by reference in paragraph (b) of this section 12 months prior to the start of the 120-month inspection interval, '
subject to the limitations and modifications listed in paragraph (b) of this section? Instead, we proposed to begin the Second Ten-Year inspection interval for LGS, Unit 1 and Common, as normally scheduled, using the existing Code requirements (i.e., First Ten-Year interval requirements), as described in Section XI of the 1906 Edition of the Code. The rationale for this proposed citemative for updating the ISI, IST, and Repair and Replacement Programs for LGS, Unit 1, is based on PECO Energy's plans to update both the Unit I and Unit 2 programs simultaneously to the same Edition and Addenda of the Section XI Code that will be in effect 12 months prior to the start of the LGS Unit 2 Second Ten-Year inspection Interval, as required by 10CFR50.55a. The LGS Unit 2 Second Ten-Year Inspection Interval is scheduled to begin in the year 2000.
However, during subsequent conversations with the NRC concerning our request regarding this alternative approach for updating the subject programs as required by 10CFR50.55a(g)(4)(ll), the NRC indicated that additional information was necessary in order to continue its review.
'Therefore, the following information is being provided as requested by the NRC in order to support the continued review of our request.
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' 9509290131 950925 ; ,
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,' September 25,1995' Page 2 Enclosure 1 - Synopsis of the ASME Section XI Programs Applicable to the Second Inspection interval.
Attachment 1 - ISI Program Relief Requests Applicable to the Second inspection interval.
Attachment 2 - Code Cases Applicable to the LGS Unit 1 ISI and Repair and Replacement Programs Applicable to the Second Inspection Interval.
Attachment 3 - LGS IST Relief Requests Applicable to the Second Inspection Interval.
As previously requested in our letter dated April 27,1995, we would appreciate the NRC's review and approval of this request by December 1,1995, in order to facilitate consistency and commonality in upgrading the LGS, Units 1 and 2, ISI, IST, and Repair and Replacement Programs for the Second Ten Year inspection Interval.
If you have any questions or require additional information, please do not hesitate to contact us.
Very truly yours,
- e 1 G. A. Hunger, Jr.
Director - Licensing Enclosure Attachments cc: T. T. Martin, Administrator, USNRC, Region I (w/ enclosure & attachments)
N. S. Perry, USNRC Senior Resident inspector, LGS (w/ enclosure & attachments) i l
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ENCLOSURE 1
) Synopsis of the ASME Section XI Programs Applicable to the Second Inspection Interval 1
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ENCLOSURE 1 )
- l PECO ENERGY COMPANY
- LIMERICK GENERATING STATION, UNIT 1 UPDATE OF ASME SECTION XI PROGRAMS j FOR SUCCESSIVE TEN YEAR INSPECTION INTERVALS
. SYNOPSIS OF THE ASME SECTION XI PROGRAMS APPLICABLE TO THE ]
SECOND INSPECTION INTERVAL j
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The following is a synopsis of how PECO Energy Company plans to satisfy the requirements put forth in Title 10, Code of Federal Regulations, Part 50 (10CFR50), Section 50.55a, " Codes and Standards", paragraphs (f)(4), " Inservice Testing Requirements," and (g)(4), " Inservice Inspection Requirements," for the Limerick Generating Station (LGS), Unit 1, during an Interim time period of the second inspection Irderval.
The first inspection interval of LGS, Unit 1 began on February 1,1986, which was the date the unit entered commercial service. At that time, the inservice inspection (ISI), inservice Testing (IST) and Repair and Replacement (R&R) Programs were developed to satisfy the requirements of the American Society of Mechanical Engineers (ASME), Boller and Pressure Vessel Code 1 (B&PVC),Section XI (hereinafter referred to as the Code),1980 Edition including Addenda through the Winter 1981 Addendum. In December 1990, at the completion of the third refueling outage, these Programs were voluntarily updated to meet the requirements of the 1906 Edition i l i of the Code. This edition of the Code was the latest approved edition at that time, and was the i edition required to be used for the ISl, IST, and R&R Programs at LGS, Unit 2. The i requirements of the 1906 Edition of the Code, applicable to the first inspection Interval, have e been implemented since the end of the third refueling outage, and will be completed by the end of the Sixth Refueling Outage (IR06). The end of the first inspection interval for LGS, Unit 1 wul coincide with the completion of 1R06, currently scheduled for February 23,1996. At that time, all first inspection interval requirements will be completed, unless NRC approval of requests for l relief from certain Codo requirements have been secured or the need for additional relief has l been Identified. Complete sausfaction of the first interval Code requirements will be pursued by 1 1
the end of the eleventh year following the date of commercial service, as required by 10CFR50.55a(f)(5)(lv) and (g)(5)(lv).
I l The end of the sixth refueling outage will also mark the beginning of the second inspection l interval for LGS, Unit 1. As required by 10CFR50.55a(f)(4)(ll) and (g)(4)(ii), the ISI, and IST l
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- Programs must comply with the requirements of the latest edition and addenda of the Code incorporated by reference in paragraph (b) of 10CFR50.55a,12 months prior to the start of the
! Inspection interval, subject to the limitations and modifications listed in paragraph (b) of ,
10CFR50.55a. 1 For the second inspection interval of LGS, Unit 1, the latest edition and addenda of the Code incorporated by reference in 10CFR50.55a is the 1909 Edition, no addenda. Therefore, the ,
ASME Section XI Programs would need to be updated to satisfy the requirements put forth in l this edition of the Code. l l
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ENCLOSURE 1 (Cont)
- proposed an attemative approach to the above for an interim time period during the second
- Inspection interval. This altemative approach to updating the ASME Programs to the 1989 j Edition of the ASME Section XI Code is to continue to use the existing Program Documents (i.e.
ISI, IST, and Repair / Replacement Programs) to satisfy the examination, testing, and i repair / replacement requirements for an interim time period of the second inspection interval.
- Use of this alternative approach la planned untu LGS, Unit 2 completes it's first ten year
- Inspection interval and it's ASME Section XI Programs must be updated for the second i inspection interval. This is currently scheduled for January 8,2000. At that time, both Units wil be simultaneously updated to the edition of Section XI Code mandated by 10CFRSO.55a 12 j months prior to the start of the LGS, Unit 2 second inspection interval. Therefore, the time period for use of the attemative approach for the LGS, Unit 1 ASME Section XI Programs wHi
- encompass approximately four (4) years and one refueling outage (Seventh Refueling Outage, 1R07), currently scheduled to begin April 4,1998. The Eighth Refueling Outage (1R08) of LGS,
- Unit 1, currently scheduled for AprH 1,2000, will utuize ASME Programs updated to satisfy the latest regulatory requirements, at that time.
l Since few significant changes have been made to the Code between the 1986 Edition and the 1989 Edition, implementation of the existing Programs, whue written to satisfy the 1986 Edition of the Code, will yield results equivalent to programs written to satisfy the requirements of the 1989
- Edition of the Code, as identified below.
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- ISI Program (Specification NE-42)
I i With respect to the ISI Program Implementation, the examinations of Class 1,2, and 3 l components, performed during the first refueling outage of LGS, Unit 1 will be repeated, to the j extent applicable, during the seventh refueling outage (i.e., first outage of the second inspection interval), using all currently applicable procedures and guidelines. This approach wHI satisfy the
- Section XI Code requirement of IWB , IWC , and IWF-2420 for successive examinations to be performed in the same sequence as that established during the first inspection interval, to the extent practical.
l j A review of the 1986 and 1989 Code Editions indicates that the only significant differences
- between the ISI requirements of these two versions of the Code are as follows
) The addition of Mandatory Appendix Vil, Qualification for Nondestructive Examination Personnel for i Ultrasonic Examination:
! PECO Energy's current written practice, and that of it's NDE contractors, is equivalent to tlw 4
requirements of IWA-2300 and Appendix Vil for all cases of qualification, training and certification except Level i and 11 practical examinations for UT performance demonstrations for examination of carbon steel piping welds using " flawed" specimens. Bolting examinations meet IWA-2300 and Mandatory Appendix VI. Reactor Pressure Vessel examinations meet IWA-2300. In addition, the qualification, training, and certification for personnel and procedures are sufficient to i demonstrate compliance with Regulatory Guide 1.150 and NUREG-0619. Austenitic piping weld examinations meet lWA-2300, Mandatory Appendix 111, and Generic Letter 88-01.
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ENCLOSURE 1 (Cont)
Compliance with the above Code requirements and Regulatory Positions is sufficient to ensure that examination personnel have the training and qualifications necessary to detect flaws before
- they exceed the standards of IWA-3500.
Additionally, PECO Energy Company's NDE contractor (General Electric Co.), qualifies it's
, examinailon personnel to the latest Code requirements, for performance of Code examinations at other utgity stations which are required to meet Mandatory Appendix Vll. While these personnel are not required to meet this Appendix under the current LGS 1 ISI Program, their qualification and certification to the latest Code requirements are inherently brought forth.
Examination Category B-A Examination requirements for successive intervals:
While the examination requirements for Reactor Pressure Vessel (RPV) welds was changed by the 1989 Edition of the Code, from examination of one weld each, in the shell, head, and repair areas; to examination of all welds in the shell, head, and repair areas, this change wHl not be impacted by the alternative ISI Program planned for use during a portion of the second inspection interval This is due to the fact that the first interval RPV shell weld examinations were initially performed during the second refueling outage of LGS, Unit 1. Accordingly, these examinations are required to be repeated beginning with the Eighth Refueling Outage. Since the Eighth Refueling Outage is not scheduled to begin until April 1,2000, the LGS, Unit 1 ISI
! Program will be updated to the latest approved Code edition by that time, and the latest Code requirements wHI be applied to the examination of the RPV welds.
Articles IWB-3000 and IWC-3000, Acceptance Standards:
l' While changes have been made to the Acceptance Criteria Articles of the Code (Articles (WB-
- and IWC-3000), genetic use of the 1989 version of these Articles is not planned. Any changes which may have taken place between the 1986 Edition and the 1989 Edition wHI be considered for significance, at the time the criteria is applied to the specific examination result.
I No other significant differences have been identified between the current LGS, Unit 1 ISI Program and the requirements of the 1989 Edition of the Code.
All ISI Program Relief Requests, approved for use during the first inspection Interval are being
- resubmitted with this correspondence for approval for use during the second Inspection interval. The relief request identification number, Code requirement applicabuity, date of original submittal and date of NRC approval are tabulated on Attachment 1. Use of these Relief Requests wHl apply during the Interim time period described, When the LGS, Unit 1 Programs are updated to the latest edition of the Code, the need for these and other Rellef Requests wHI be reconcHed.
All Code Caces which have been used during the first inspection interval of LGS, Unit 1 are planned for use during the second inspection interval. Attachment 2 lists the Code Cases which are planned for use during the second interval, along with an identification of the generic NRC approval status of each case.
Use of these Code Cases WHI apply during the interim time period described. When the LGS, Unit 1 Programs are updated to the latest edition of the Code, the need for these and other Code Cases wHl be reconciled.
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l ENCLOSURE 1 (CorW)
! IST Program (Specification ML-008)
} The IST Program wHI continue to implement the testing requirements of Subsections IWP and IWV of the 1986 Code edition, as modified by approved relief requests for pump and valve testing of LGS, Unit 1. Additionally, portions of the 1989 Code requirements have been voluntarNy adopted, as explained below. Further, the following actions are planned:
The LGS, Unit 1 IST Program is planned for revision as a result of completion of an LGS IST Basis Document Project. This project is underway to identify any necessary revisions to the IST Program as a ruult of issuance of NUREG 1482 Guidelines for Inservice Testing at Nuclear Power Plants (APRIL 1995), and to verify compliance with the 1986 Code component and testing scope requirements. The LGS IST Basis Document wBl provide a component level justification for the content of, as well as exclusions of components from, the IST Program.
. A review of the 1986 and 1989 Code Editions indh M that the only significant differences between the IST requirements of these two versions of the Code are as follows:
Changes in vibration measurement methods for vertical line shaft and centrifugal pumos: (OMa-1988 l
Addendum, Subparagraph 4.6.4)
The LGS Vibration Monitoring Program complies with the above vibration monitoring requirements of the OM-6,1989 Code Edition. Therefore, these requirements of the 1989 Edition of the Section XI Code will be satisfied by this Program.
Changes in frequency response calibration range for vibration transducers: (OMa 1988 Addendum, l i Subparagraph 4.6.1.6) !
The LGS Vibration Monitoring Program complies with the above vibration monitoring requirement of the OM-6,1989 Code Edition. Therefore, these requirements of the 1989 Edition of the Section XI Code will be satisfied by this Program.
Position Indication testing for Category B passive valves: (OMa-1988 Addendum, Paragraph 4.1 and Table 1)
! The LGS IST Program presently performs position indication testing on all manual injection line j isolation valves for ECCS systems as well as other selected Category B passive valves. l All IST Relief Requests, approved for use during the first inspection interval are being resubmitted with this correspondence for approval for use during the second inspection interval.
- The relief request identification number, Code requirement applicablity date of original submittal and date of NRC approval are tabulated on Attachment 3. Use of these Relief Requests wul apply during the Interim time period described. When the LGS, Unit 1 Programs are updated to the latest edition of the Code, the need for these and other Relief Requests wil be reconcRed. ;
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i ENCLOSURE 1 (Cont)
I There are no Code Cases currently utilized for implementation of the IST Program during the first inspection interval of LGS, Unit 1. At this time, no Code Cases are planned for use during the
- second inspection interval.
Repair and Replacement Program (Specification M-679) i The Repair and Replacement Program will continue to be implemented in accordance with the requirements of the 1986 Edition of the Section XI Code, as it has been during the first ;
inspection interval. There are no significant differences between the 1986 Edition and the 1989 !
Edition of the Section XI Code regarding the requirements for conducted ASME Section XI I Repairs or Replacements.
All R&R Program Relief Requests, approved for use during the first inspection interval are being I resubmitted with this correspondence for approval for use during the second inspection interval. ,
1 2 These relief requests are included in the listing identified for the ISI Program above.
All Code Cases which have been used during the first inspection interval of LGS, Unit 1 are planned for use during the second inspection interval. Attachment 2 lists the Code Cases which are planned for use during the second interval, along with an identification of the generic NRC i approval status of each case.
Conclusion
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Therefore, the use of the current ASME Section XI Programs, writtw to '.he 1986 Edition of the Code, along with the NRC approved Code Cases and Relief Requests applicable, yields an )
examination, testing, and repair and replacement effort which is inherently equivdent to a
- program written to directly satisfy the 1989 Edition of the Section XI Code.
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i ATTACHMENT 1 Inservice Inspection (ISI)
Program Relief Requests 1 Applicable to the Second Inspection Interval
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Page 1 of 4 ATTACHMENT 1 1S1 PROGRAM RELIEF REQUESTS APPLICABLE TO THE SECOND INSPECTION INTERVAL RELIEF REQUEST APPROVAL EXAMINATION CATEGORY ITEM NO. DATE NQ RR41 B-A Pressure B1.22 Head welds Rev.1 retalning welds (Meridional) 3/1/94 in reactor vessel RR-02 B-L-2 Pump casings B12.20 Pump casirg 3/4/88 (Internal Surfaces)
RP-03 B-M-2 Valve bodies B12.50 Valve body, exceeding NPS 4 3/4/88 (Internal Surfaces)-
RR 04 F-C Component F3.50 Spring type supports, constant 3/4/88 standard supports load type supports, shock absorbers, hydraulle and mechanical type snubbers.
RR-05 C-C Integral C3.10 Integrally welded 3/4/88 attachments for attachments vessels, piping, (Pressure Vessels) pumps, and valves C3.20 Integrally welded attachments (Piping) 4 C3.30 Integrally welded attachments (Pumps)
RR-06 C-A Pressure C1.10 Shell circumferential 3/4/88 retalning welds in welds pressure vessels RR-07 C-G Pressure C6.10 Pump casing welds 3/4/88 4 retalning welds in pumps and valves RR-08 B-D Full penetration B3.90 Nozzle to vessel welds 3/4/88 welds of nozzles (Reactor Vessel) in vessels (Inspection program B)
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- ATTACHMENT 1 (Cont)
REUEF REQUEST APPROVAL EXAMINATION CATEGORY ITEM NO. DATE
.NQ RR-09 FA Plate and F1.10 Mechanical connections to pressure 3/1/94 shell type retaining components and building supports structure F1.20 Weld connections to building structure F1.30 Weld and mechanical connections at intermediate joints in multiconnected integral and non-integral supports.
F1.40 Component displacement settings of guldss and stops, misalignment of supports, assembly of support items.
FB Linear type F2.10 Mechanical connections to pressure supports retalning components and building structure F2.20 Weld connections to building structure F2.30 Weld and mechanical connections at intermediate joints in multiconnected Integral and non-Integral supports.
F2.40 Component displacement settings of guides and stops, misalignment of supports, assembly of support items.
F-C Component F3.10 Mechanical connections to pressure standard retalning components and building supports structure
- F3.20 Wold connections to building structure F3.30 Weld and mechanical connections at intermediate joints in multiconnected Integral and non-integral supports.
F3.40 Component displacement settings of guides and stops, misalignment of supports, assembly of support items.
F3.50 Spring type supports, constant load type supports, shock absorbers, hydraulic and mechanical type snubbers.
I Page 3 of 4 ATTACHMENT 1 (Cont)
REUEF '
REQUEST APPROVAL EXAMINATION CATEGORY ITEM NO. ,[261E
.tLQ RR 10 B-F Pressure B5.130 NPS 4 or larger dissimilar metal 3/4/88 retaining dissimilar butt welds (Piping) ;
metal welds RR 12 ASME Code Case (s) Rev.1 Authorization Request 6/29/95 RR 13 C-H AllPressure Pressure Vessels Rev.2 Retaining C7.10 Pressure Retaining Components Pending Components C7.20 Pressure Retalning Components Piping C7.30 Pressure Retalning Components C7.40 Pressure Retaining Components Pumps C7.50 Pressure Retalning Components C7.60 Pressure Retaining Components Valves C7.70 Pressu o Retaining Components :
C7.80 Pressure Retaining Components ;
D-A, Systems in D1.10 Pressure Retaining Support of Reactor Components Shutdown Function D-B, Systems in D2.10 Pressure Retaining Support of Emergency Components Core Cooling, Containment j Heat Removal, l 3
Atmosphere Cleanup, I 1
and Reactor Residual Heat Removal D-C, Systems in D3.10 Pressure Retalning Support of Residual Components
. Heat Removal From Spent Fuel Storage i
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l ATTACHMENT 1 (Cont) l RELIEF REQUEST APPROVAL EQ EXAMINATION CATEGORY ITEM NO. DAIE RR 14 Augmented Examination 3/1/94 Programs RR 15 B-P, All Class 1 B15.10 Pressure Retaining 4/14/93 Pressure Retaining thru Boundary Components B15.71 RR-22 Repair / Replacement 6/29/95 Hydrostatic Pressure Test (Code Case N416-1)
RR-23 Code Case N-496-1 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> hold time. Pending
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4 ATTACHMENT 2 Code Cases Applicable to the LGS, Unit 1 ISI and Repair and Replacement Programs
Applicable to the Second Inspection Interval 1
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. ATTACHMENT 2 Code Cases Applicable to the LGS, Unit 1 ISI and Repelr/ Replacement Programs Approved by USNRC Code Case Reg. Guide Number .Ijgg 1.147 N 236-1 Repair and Replacement of Class MC Vessels Yes (See Note 1)
N-307-1 Revised Ultrasonic Examination Volume for Yes
! Class 1 Bolting, Table IWB-2500-1, Examination Category B-G-1, when the examinations are conducted from the center-druled hole N-389 Alternative Rules for Repairs, Yes Replacements, or Modifications N-406 Altemate Rules for Replacement Yes (Rev 8)
N-416-1 Altemative Presssure Test Requirement for No Welded Repairs or installation of Replacement (See Note 3) ,
items by Welding, Class 1,2 and 3 4 i N-427 Code Cases h inspection Plans Yes i i
N-4351 Alternative Examination Requirements for Yes Vessels with Wall Thickness 2 in, or less N-460 Alternative Examination Coverage for Yes l Class 1 and Class 2 Welds j l
' Yes N-461 Alternate Rules for Piping Calibration Block Thickness N-479-1 Bolling Water Reactor (BWR) Main Steam Yes Hydrostatic Test N-495 Hydrostatic Testing of Relief Valves Yes N498-1 Altemative Rules for 10-Year Hydrostatic No Pressure Testing (See Note 2)
NOTES (1) Limited to Article 2000 for Leakage Test following repairs, modifications, or replacements.
(2) This Code Case has not been endorsed for use by the NRC in Reg. Guide 1.147. See '
Relief Request RR-12 for justification of its use in this program. ,
l (3) This Code Case has not been endorsed for use by the NRC in Reg. Guide 1.147. See Relief Request RR-22 for justification of its use in this program.
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! ATTACHMENT 3 i
Inservice Testing (IST)
Program Relief Requests i' Applicable to the Second Inspection Interval 1
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ATTACMENT 3 LGS IST RELIEF REQUEST GPRR-1 Approved: 3/5/91 GPRR-2 Approved: 2/17/93 GPRR-3 Approved: 2/17/93-GPRR-4 Approved: 2/20/92 GVRR-1 Approved: 3/5/91 GVRR-2 Approved: 3/5/91 GVRR-3 Approved: 3/5/91 GVRR-4 Approved: 3/5/91 - 2/17/93 GVRR-5 Approved: 3/5/91 -
2/17/93-GVRR Approved: 3/5/91 -
2/17/93 20-VRR-1 Approved: 3/5/91 -
41-VRR-1 Approved: 3/5/91
! 41-VRR-2 Approved: 3/5/91 41-VRR-3 Approved: 3/5/91
. 41-VRR-4 Approved: 3/5/91
! 41-VRR-5 Approved: 3/5/91 i 43-VRR-1 Approved: 2/17/93
! 46-VRR-1 Approved: 3/5/91 47-VRR-1 Apporved: 3/5/91 l
- 48-VRR-1 Approved
- 3/5/91 I 49-VRR-1 Approved: 3/5/91 l 51-VRR-1 Approved: 3/5/91
! 51-VRR-2 Approved: 9/27/93
!- 52-VRR-1 Approved: 2/17/93 i- 55-VRR-1 Approved: 3/5/91 - 2/17/93
! 55-VRR-2 Approved: 3/5/91 -
2/17/93 59-VRR-1 Approved: 3/5/91
- 90-VRR-1 Approved
- 3/5/91 4
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