ML20198H685
| ML20198H685 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 12/22/1997 |
| From: | Jeffery Wood CENTERIOR ENERGY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 2506, NUDOCS 9801130368 | |
| Download: ML20198H685 (27) | |
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.Mus K. Wood 419 249 2300 stp l%extont.Nxkar fax 41V3214331 Docket Number 50 346 License Number NPF 3 Serial Number 2506 Deccinber 22, 1997 United States Nuclear Regulatory Commission
- Document Control Desk Washington, DC 20555
Subject:
Request for Relief from Certain Amerlean Society of Mechanical Engineers (ASME)
Code Requirements ibt inse:Vice inspection for the Davis Besse Nuclear Power Station Ladies and Gentlemen:
In the Federal Register (FR), dated August 8,1996 (61 FR 41303), the Nuclear Regulatory Commission (NRC) amended its regulations to incorporate by reference the 1992 Edition and Addenda of Subsections IWE and IWL of Section XI of the ASME Code. Subsections IWE.
" Requirements for Class Metallic Containment (MC) and Metallic Lines of Class Concrete Containment (CC) Components at Light Water Coobd Plants" cnd IWL," Requirements for Class CC Concrete Components at Light Water Cooled Plants," give the requirements for inservice inspection (ISI) of Class MC and Class CC. The Davis-Besse Nuclear Power Station (DBNPS) containment vessel is a free standing metallic structure which was constructed in accordance with ASME Section 111, Subsection B for Nuclear Vessels,1968 Edition including the Summer 1969 Addenda. The rules of Subsection IWL are not applicable to the DBNPS Containment Vessel.
Toledo Edison previously requested relief from several IWE examination acquirements b y lettet dated September 8,1997,(Serial Number 2482). 'these relief requests are hereby withdrawn.
The purpose of this letter is to request relief pursuant to 10CFR50.55a(a)(3) and (g)(5)(iii) from certain requirements of Section XI of the American Society of Mechanical Engineers (ASME)
Boiler and Pressure Essel Code. Toledo Edison is a participant in the Electric Power Research Institute (EPRI) project for the preparation of a Generic IWE/lWL Program and Guide. This a
program was described to the NRC on October 23,1997, during a meeting between the NRC, djg EPRI, Nuclear Energy Institute (NEI), and several utilities. As a lead plant in this project, the DBNPS is submitting these relief requests on behalf of the EPRI program.
Docket Number 50 346 License Number NPP 3 Serial Number 2506 Page 2 Relief Requests RR El through RR E9 are based on the generic relief requests contnined in the EPRI Ocneric IWE/lWL Program and Guide. Relief Requests RR-E8 and RR E9 were identified subsequent to the October 23,1997, meeting with the NRC. Relief Request RR E10 is specific to the DilNPS and is not part of the EPRI program. Details concerning the requested relief are provided in attached Relief Requests RR El, RR E2, RR E3, RR E4, RR ES, RR-E6, RR E7, RR E8, RR E9, and RR E10.
Relief Request RR El requests relief from Section XI of the ASME Code,1992 Edition,1992 Addenda, Code items E5.10 and E5.20 which require a vi:,aal examination of met d containment seals and gaskets. Examination of most seals and gaskets require thejoints to be disassembled.
Containment seals and gaskets will be proven wiequate through the performance of 10CFR50 Appendix J testing.
Relief Request RR E2 requests relief from Section XI of the ASME Code,1992 Edition,1992
- Addenda, Subarticle IWA 2300," Qualifications of Nondestructive Examirntion Personnel,"
which requires qualification and certification of nondestructive examination personnel in accordance with ANSI /ASNT CP-189,1991," Standards for Qualification and Certification of Nondestructive Testing Personnel." The current DilNPS ISI program requires the use of SNT-TC 1 A," Personnel Qualification and Certification in Nondestructive Testing," which causes the development and administration of a second qualification program. Neither CP-189 nor SNT-TC 1 A specifically include visual examination which is the primary nondestruc'ive examination required by Subsection IWE. Nondestructive examination personnel performing IWE examinations will be qualified in accordance with SNT-TC-1 A.
Relief Request RR E3 requests relief from Section XI of the ASME Code,1992 Edition,1992 Addenda, Subarticle IWE 2200(g), which requires a preservice exanination of reapplied paint or coatings to steel containments. Neither paint or coatings contribute to the structural integrity or leak tightness of the containment. Reapplied paint or coating will be examined in accordance with the Davis Besse coatings maintenance program.
Relief Request RR E4 requests relief from Section XI of the ASME Code,1992 Edition,1992 Addenda, Subarticle IWE 2500(b), which requires visual examination of paint or coatings prior to removal. Neither paint or coatings contribute to the structural integrity or leak tightness of the containment. Paint or coating degradation would be revealed by the visual examinations conducted as required by Subsection IWE of ASME Section XI. If degradation of the paint or coating is identified, measures will be applied to determine if the containment pressure boundary is affected.
Relief Request RR-E5 requests relief from Section XI of the ASME Code,1992 Edition,1992 Addenda, Subanicle IWE-5240," Visual Examination," which requires u VT-2 visual examination following repair, replacement, or modification. A VT-2 examination for evidence m' air leakage will not provide effective detection ofleakage. Testing in accordance with 10CFR50 Appendix J will be performed.
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Docket Number 50>346 License Number NPF-3 Serial Number 2506 Page 3 Relief Request RR-E6 requests relief from Section XI of the ASME Code,199. '?dition,1992 Addenda, Subarticle IWE 2420(b) and IWE 2420(c), which require repaired areas be examined during the next inspection period. Repairs restore the component to an acceptable condition for continued service. Successive examinations will not be required for repaired areas.
Relief Request RR E7 requests relief from Section XI of the AShiE Code,1992 Edition,1992 Addenda, Code item E8.20, which requires a bolt torque or tension test for bolted connections that have not been disassembled and reassembled during the inspection it'terval. The leak tightness of bolted connections will be verified through the performance of 10CFR50 Appendix J testing.
Relief Request RR E8 requests relief from Section XI of the ASME Cou 1992 Edition,1992 Addenda, Subarticle 1WA 2210," Visual Examinations," which establishes requirements for vicual examination procedures. The 10CFR50.55a was amended as cited in the Federal Register (61FR41303). This amendment relaxed the requirements for performing remote visual examination. These same criteria will be used to perfonn the direct visual examination.
Relief Request RR E9 requests relief from the Section XI of the ASME Code,1992 Edition, 1992 Addenda, Subarticles IWE-2500(c)(3) and IWE-2500(c)(4), which contain requirements for estab1ishing augmented examination area grids and determining the minimum thickness withia cach grid. Grid sizes and the number of thickness reading will be determined by size of the au2mented examination area. Ultrasonic thickness examinations will be performed at grid line intersections, Relief Request RR E10 which is specific to the DBNPS, requests relief from Section XI of the ASME Code,1992 Edition,1992 Addenda, Subsection IWA-4000," Repair and Replacement,"
for containment repairs and replacements. Toledo Edison proposes that repairs / replacements to the containment vessel will be inaccordance with the requirements of the 1986 Edition, No Addenda of ASME Section XI, and preservice examinations will be conducted in accordance with the requirements of Subsection IWE of the 1992 Edition,1992 Addenda of ASME Section XI.
Approval of these relief requests is requested prior to February 1,1998. It is Toledo Edison's understanding that EPRI and the Nuclear Energy Institute (NEI) have been in contact with the NRC staff to request a four week turn around to these requests. The results of the NRC review are required in order that the remaining utilities participating in the EPRI Generic IWE/lWL Program and Guide project may prepare and submit similar relief requests for their respective plants. As several plants have only one or two outages available to complete the expedited examinations irquired by IWE prior to September 6,2001, the results of the NRC review are required to facilitate adequate planning of these examinations.
Docket Number 50 346 License Number NPF-3 Serial Number 2506
. Page 4. -
Shoul6 you have any questions or require additional inforniation, please contact Mr. James L.
Freels,,ianager - Regulatery Affairs, at (419) 321 8466.
i Very truly yours, t
CAK/dic -
' Attachment cc: A. It lleach, Regional Administrator, NRC Region 111 i
A. G. Ilansen, NRC/NRR Project Manager S. J. Campbell, NRC Region 111, DB 1 Senior Resident inspector Utility Radiological Safety Board t
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Docket Number 50 346 License Number NPF 3 Serial Number 2506 Attachment Page1 CONTAINMENT INSPECTION SEALS & GASKETS RELIEF REQUEST RR El SYSTEM / COMPONENT (S) FOR WilLMRELIEFIS REOUESTED Seals and gaskets of Class MC pressure retaining components, Examination Category E-D, item Numbers E5.10 and E5.20 ofIWE 2500," Examination and Pressure Test Requirements," Table IWE-2500-1. ASME Section XI,1992 Edition,1992 Addenda.
CODE REOUIREMENT(S):
IWE-2500 Table 1WE 25001 requires seals and gaskets on airlocks, hatches, and other devices to be visually examined, VT 3, once each interval to assure containment leak tight integrity.
CODE REOUIREMENT FROM WillCII RELIEF IS REOUESTED:
Reliefis requested from perfonning the Code required visual examination. VT-3, on the above identified metal containment seals ani caskets.
HASIS FOR RELIEF:
10CFR50.55a was amended, as cited in the Federal Register (61 FR41303), to require the use of the 1992 Edition,1992 Addenda, of Section XI when performing cociainment examinations.
The penetratloas discussed below contain sca's and gaskets:
. Electrical Penetrations:
Electrical penetrations use a header plate attached t; a containment penetration no721e flange with redundant 0 rings between the header plate and flange face. Modules through which electrical conductors pass are lastalled in the header plate. One type, manufactured by Amphenol uses seals and gaskets to assure leak tight integrity, A second type, manufactured by Conax uses a set of compression fittings. Replacement modules for the Amphenol penetrations use a combination of 0-rings and compression fittings. Each penetration is pressurized with dry nitrogen to maintain and monitor integrity and to prevent the intmsion of moisture into the penetration.
These seals and gaskets cannot be inspected without disassembly of the penetration to gain access to the seals and gaskets.
Docket Number 50 346 i
License Number NPF 3 Serial Number 2506 Attachment Page 2 Containment Personnel. Equinment. and Emercenev Escape llatches The Personnel Equipment, and Emerg,ency Escape flatches utilize an inner and outer door with gasket surfaces to ensure a leak tight integrity. These hatches also contain other gaskets and seals such as the handwheel shaft seals, electrical penetrations, blank flanges, and equalizing pressure connections which require disassembly to gain access to the gaskets and seals.
Seals,md gaskets receive a 10CFR50 Appendix J, Type B test. As noted in 10CFR50 Appendix J, the purpose of Type B tests is to measure leakage of containment or penetrations whc,x design incorporates resilient seals, gaskets, sealant compounds, and electrical penetrations fitted with flexible metal seal assemblies. Examination of seals and gaskets require thejoints, which are proven adequate through Appendix J testing, be disassembled. For electrical penetrations, this would involve a pre-m m 'ance Appendix J test, determination of cables at electrical penetrations if enough cabte slack is not available, disassembly of the joint, removal and examination of the serls and ga? cts, reassembly of thejoint, re termination of the cables if necessary, post maintenance testing of the cables, and a post maintenance Appendix J test of the penetration. The work required for the Containment 1-latches would be similar except for 1%
determination, re termination, and testing of cables. This imposes the risk that equipment could be damaged. The 1992 Edition,1993 Addenda, of ASME Section XI recognizes that disassembly ofjoints to perform these examinations is not w trranted. Note 1 in Examination Category E D was modified in the 1995 Edition of ASME Section XI to state that scaled or gasket connections need not he disassembled solely for perforraance of examinations. Ilowever, without disassembly, most of the surface of the seals and gaskets would be inaccessible.
For those penetrations that are routinely disassembled, a Type B test is required upon final assembly and prior to start up. Since the Type B test will assure the leak tight integrity of primary containment, the performance of the visual examination would not increa3e in the level of safety or quality.
Seals and gaskets are not part of the containment pressure boundary under current Code rules (NE-1220 (b)). When the airlocks and hatches containing these materials ate tested in accordance with 10 CFR 50, Appendix J, degradation of the seal or gasket material would be revealed by an increase in the leakage rate. Corrective measures would be applied and the component retested. Repair or replacement of seals and gaskets is not subject to Code (1992 Edition,1992 Addenda) rules in accordance with Paragraph IWA-4111(b)(5) of ASME Section XI.
The visual examination of seals and gaskets in accordance with IWE-2500, Table IWE-2500-1 is a burden without any compensating increase in the level of safety or quality.
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+ Docket Number 50 346 l
Licenac Number NPF.3 1
- Serial Number 2506 i
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i Reliefis requested _in accordance with 10CFR50.55a(aX3Xil). Compliance with'the specified j
requirements of this section wou d result in hardship or unusual difficulty whhout a compensating increase in the level of quality and safety. Testing the seals and gaskets in.
l accordance with 10CFR50, Appendix J will provide adequate assurance of the leak tight:
integrity of the seals and gaskets.=
The requirement to examine seals and gaskets has been removed in the rewrite of Subsection 1
lWE of ASME Section XI..This rewrite has been approved by ASME and is scheduled to be -
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published in 1998.
ALTERNATIVE EXAMINATIOf 4Sh
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iThe leak tightness of seals and gaskets will be tested in accordance with 10CFR50 Appendix J l
The 10CFR50, Appendix J Type B testing is performed at least once cach inspection interval.
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Docket Number 502346 License Number NPF 3 Serial Number 2506 Attachment Page 4 CONTAINMENT INSPECTION hDE PERSONNEL QUALIFICATION & CERTIFICATION RELIEF REQUEST RR E2 SYSTEM /COMPONFKr(S) FOR WIIICil RELIEF IS REOUESTEJh All components subject to examination in accordance with Subsection IWE of the 1992 Edition, 1992 /.ddenda of ASME Section XI.
CODE REOUIREMENTS:
Subarticle IWA-2300, " Qualification of Nondestructive Examination Personnel," requires qualification of nondestructive examination personnel to CP 189 - 1991," Standard for Qualificatien and Certification of Nondestmetive Testing Personnel," as amended by the ASME Section XI.
CODE REOUIREMENTS FROM WillCil RFilEF IS REOUESTED:
Reliefis requested from the provisions of Subarticle IWA 2300, " Qualification of Nondestructive Examination Personnel." This regt,lres NDE personnel to be qualified and certified using a written practice in accordance with CP 189, Standard for Qualification and Certification of Nondestructive Testing Personnel, as amended by the requirements of Subarticle IWA 2300.
.HASIS FOR RELIEF:
10CFR50.55a was amen <ted, as cited in the Federal Register (61FR41303), to require the use of the 1992 Edition,1992 Addenda, of Section XI, when perfonning containment examinations. In addition to the requirements of Subsection IWE, this also imposes the requirements Subsection IWA, General Requirements, of the 1992 Edition,1992 Addenda of Section XI. Subarticle IWA-7300. requires qualification of nondestructive examincion personnel to CP 189, as amended by Subarticle 1WA-2300.
A written practice based on the requirements of CP 189, as amended by the requirements of the Subarticle IWA-2300, to implement Subsection IWE duplicates ellbrts already in place to for all other subsections. The Davis Besse Nuclear Power Station Second Ten Year Insersice inspection Program is written to meet the 1986 Edition, No Addenda of Section XI. Subarticle IWA-2300 of the 1986 Edition requires a written practice based on SNT-TC-1 A," Personnel Qualificat on and i
Cenification in Nondestmetive Testing," as amended by the requirements of Subarticle IWA 2300.
Further, Subarticle IWA 2300 of the 1992 Edition.1992 Addenda, sta:es," Certifications based on SNT-TC-1 A are valid until recertification is required."
Docket Number 50 346 l.icenra Number NPF-3 Serial Number 2506 Attachment Page 5 Visual examination is the primary nondestructive examination method required by Subsection IWE. Neither CP 189 nor SNT-TC 1 A specifically includes visual examination. Therefore, the Code requires qualification and certification to comparable levels as defined in CP 189 or SNT TC-1 A, as applicable, and the employer's written practice. Ultrasonic thickness examinations may also be required by Table IWE 2500-1. These examinations are relatively simple and do not require an extensive training and qualification program. Therefore, use of CP 189 in place of SNT-TC 1 A will not improve the capability of excmination personnel to perform the visual and ultrasonic thickness examinations required by IWE.
Development and administration of a second program would not enhance safety or quality and wouki serve as a bualen, particularly in developing a second written practice, tracking of certifications, and duplication of paperwork. This duplication would also apply to Nondestnictive Examination (NDE) vendor programs. Updating to the 1992 Edition,1992 Addenda, for Subsections lWB, IWC, etc., would require a similar request for relief.
Reliefis requested in accordance with 10CFR50.55a(a)(3)(ii). Compliance with the specified requirements of this section would result in hardship or unusual difficulty without a compensating increase in the level of qualiiy and safety.
The requirement to comply with IWA 2300 has been removed in the rewrite of Subsection IWE of ASME Section XI. This nmTite has been approved by ASME and is scheduled to be published in 1998.
ALTERNATIVE EXAMINATION (S):
Examinations required by Subsections lWE shall be conducted by personnel qualified and certified to a written practice based on SNT-TC-1 A and the 1986 Edition, No Addenda, of ASME Section XI. Visual examination personnel will receive specific training in conducting containment exmninations.
Docket Number 50,346 License Number NPF 3 Serial Number 2506 Attachment Page 6 CONTAINMENT INSPECTION PRESERVICE OF REAPPLIED PAINT OR COA flNGS RELIEF REQUEST RR.E3 EYSTEM/ COMPONENT (S) FOR WillCII RELIEF IS REOUESTED:
All Class MC, Subarticle IWE 2200(g), preservice examination requirements of reapplied painted or coated containments.
G)DE REOU!REMENT(S):
ASME 5ection XI,1992 Edition,1992 Addenda, Subsection IWE 2200(g) requires that when paint or coatings are reapplied, the condition of the new paint or coating shall be documented in the preservice examination records.
CODE REOUIREMENT FROM WillCH RELIEF IS REOUESTED:
Reliefis requested from the requirement to perform a preservice inspection of new paint or coatings.
HASIS FOR RELIEF:
Paint and coatings are not part of the containment pressure boundary under current Code rules as they are not associated with the pressure retaining function of the companent (Paragraph NE-2110 (b)(5) of ASME Section 111). Neither paint nor coatings contribute to the structural integrity or leak tightness of the containment. Furthernwre, the paint and coatings on the containment pressure boundary were not subject to Code mies when they were originally applied and are not subject to ASME Section XI rules for repair or replacement in accordance with IWA-4111(b)(5). The adequacy of applied coatings is verified through the inspections performed by the Davis Ilesse Nuclear Power Station (DBNPS) coating maintenance program.
Recording the condition of reapplied coating in the preservice record does not substantiate the containment stmetural integrity. Should deterioration of the coating in the reapplied area occur, the area will require additional evaluation regardless of the preservice record. Recording the condition of new paint or coating in the preservice records does not increase the level of quality and safety of the containment.
In SECY 96-080," Issuance of Final Amendment to 10CFR Section 50.55a to incorporate by Reference the ASME Iloiler and Pressure Vessel Code (ASME Code),Section X', Division 1, 4
Subsection lWE and Subnection lWL," dated April 17,1996, response to Comment 3.2 about IWE-2200(g) states,"In the NRC's opinion, this does not mean that a visual examination must
Docket Number 50-346 1.lcense Number NPF-3 Serial Number 2506 Attachment l' age 7 he performed with every application of paint or coating. A visual examination of the topeoat to determine the soundness and the condition of the topcoat should be sufilcient." 'this is currently accomplished through the inspections performed by the D13NPS coating maintenance program.
Reliefis requested in accordance with 10CFR$0.55a(a)(3)(i). The Dl!NPS coating maintenance program currently provides an adequate level of quality and safety.
The requirement to perform a preservice examination when paint or coatings are reapplied has been removed in the rewrite of Subsection IWE of ASME Section XI. This rewrite has been approved by ASME and is scheduled to be published in 1998.
AI, TERNATE EXAMINATION (Sh Reapplied paint and coatings on the containment vessel will be examined in accordance with the DilNPS coatings program. Although repairs to paint or coatings are not subject to the repair / replacement rules of ASME XI (Inquiry 97 22), repairs to the primary containment boundary, if required, would be conducted in accordance with ASME Section XI Code rules.
Docket Number 50 346 1.icense Number NPP-3 Serial Numbe. 2506 Attachment Page 8 CONTAINMENT INSPECTION VT PRIOR TO PAINT OR COATING REMOVAL RELIEF REQUEST RR E4 SYSTEM / COMPONENT (S) FOR WillCli RELIEF IS REOUESTED:
All Class MC, Subartlcle IWE 2500(b) visual examination per Table IWE-2500 1 of painted or i
coated containment components prior to removal of paint or coatings.
CollE_REOUIREMENT(S):
i ASME Section XI,1992 Edition,1992 Addenda, Subarticle IWE-2500(b) requires that when paint or coatings are to be removed, the paint or coatings shall be visually examined in accordance with Table IWE-25001 prior to removal.
CODE REOUIREMENT FROM WlilCII RELIEF IS REOUESTED:
Subarticle IWE-2500(b) requires that when paint or coatings are to be removed, the paint or coatings shall b: visually examined in accordance with Table IWE-25001 prior to removal, ljMijE FOR RillEFt 10CFR50.55a was amended, as cited in the Federal Register (61 FR41303), to require the use of ne 1992 Iklition,1992 Addenda, of ASME Section XI when performing containment examinations. Paint <md coatings are not part of the containment pressure boundary under cunent Code n i i as they are not associated with the pressure retaining function of the component (Pa..$.aph NE 2110 (b)(5) of ASME bection III). The interiors of containments are painted to prevent rusting. Neither paint nor coatings contribute to the stru:tural integrity or leak tightness of the containment. Furthemtore the paint and coatings on the containment pressure boundary were not subject to Code rules when they were originally applied and are not subject to ASME Section XI niles for repair or replacement in accordance with IWA-4111(b)(5).
Degradation or discoloration of the paint or coating materials on containment would be an indicator of potential degradation of the containment pressure boundary. Additional measures would has e to be employed to determine the nature and extent of any degradation, if present.
The application of ASME Section XI rules for removal of paint or coatings when unrelated to a ASME Section XI repair or replacement activity, is a burden without a compensating increase in quality or safety.
Reliefis requested in accordance with 10CFR50.55a(a)(3)(i). Coating inspection programs currently provide an adequate level of quality and safety.
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Docket Number 50 346 License Number NPF 3 -
Serial Number 2506 Attachment Page 9 The requirement to inspect coatings prior to removal has been removed in the rewrite of Subsection IWE of ASME Section XI. 'lhis rewrite has been approved by ASME and is i
scheduled to be published in 1998.
ALTERNA1EEXAMINATION(Sh
'ihe condition of the containm nt ves l base material will be verified prior to the application of e
se new paint or coating as required by the DBNPS Maintenance Program. If degradation is identified, additional measures will be applied to determine if the containment pressure boundary is affected. Repairs to the primary containment boundary, ifrequired, will be conducted in
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Docket Number 50 346 License Number NPF 3 Serial Number 2506 Attachment Page 10 CONTAINMENT INSPECTION VT-2 AFTER REPAIR, REPLACEMENT OR MODIFICATION RELIEF REQUEST RR E5 SYSTEM / COMPONENT (S) FOR WillCil RELIEF IS REOUESTX1h All components subject to the rules and requirements for repair, replacement or modification of Class MC,IWE 5000 system pressure testing visual examination in accordance with the 1992 Edition,1992 Addenda of ASME Section XI.
CODE REOUIREMENT(Sh
- Paragraph IWE-5240," Visual Examination," of the 1992 Edition,1992 Addenda, of ASME Section XI, requires that the requirements of Paragraph IWA-5240," Visual Examination," for visual examination, VT-2, are applicable following repair, replacement, or modification.
CODE REOUIREMENT FROM WillCII RELIEF IS REOUESTED:
Reliefis requested from performing the VT 2 visual examination in connection with system pressure testing following repair, replacement or modification under Article IWE 5000," System Pressure Tests."
)] ASIS FOR RELIEEt Repair / replacements are perfonned in aciordance with the Davis Besse Nuclear Power Station (DBNPS) remir/ replacement program which specifies the repair methods and nondestructive examinationi. accessary to ensure the original quality and construction requirements of the containment vessel are met.
10CFR50.55a was amended,as cited in the Federal Register (61FR41303), to require the use of the 1992 Edition,1992 Addenda, of ASME Section XI when performing containment examinations. Paragraph IWE 5210 states that, except as noted within Paragraph IWE 5240,
" Visual Examination," the requirements of Article IWA 5000 are not applicable to Class MC or Class CC components. Paragraph IWE-5240 states that, the requirements of Paragraph IWA-5240 (corrected from IWA-5246 to IWA-5240 in the 1993 Addenda) for visual examinations are applicable. Paragraph IWA 5240 describes a VT-2 visual examination. VT-2 examinations are conducted to detxt evidence ofleakage from pressure retaining components, with or without leakage collection systems, as required during the conduct of a system pressure test, in addition, persomiel perfonning VT 2 examinations are required to be qualified in accordance with Subarticle IWA 2300, " Qualification of Nondestructive Examination Personnel," of ASME Section XI.
4 Docket Number 50o346 License Number NPF 3 Serial Number 2506 Attachment Page11 Table IWE-2500 1, Examination Category E-P, specifies the examination method of 10CFR50, Appendix J following each repair, modification, or replacement and does not specifically identify a VT 2 visual examination.10CFR56, Appendix J provides requirements for testing as well as acceptable leakage criteria. These tests are performed by qualified personnel and utilize calibrated equipment to determine acceptability. Additionally,10CFR50.55a(b)(2)(x)(E) requires a general visual examination of the containment each period that would identify any structural degradation that may contribute to leakage. A VT 2 visual examination will not provide additional assurance of safety beyond that of current repair / replacement and 10CFR50 Appendix J practices.
Reliefis requested in accordance with 10CFR50.55a(a)(3)(i). Pressure testing in accordance with 10CFR50, Appendix J, provides an adequate level of quality.
Al/FERNATIVE EXAMINATIONfSh Testing and examination shall be conducted in accordance with 10CFR50, Appendix J. A preservice visual examination will be performed on the repair / replacement.
Docket Number 50 346 1.icense Number NPF 3 Serial Number 2506 Attachment Page 12 CONTAINMENT INFPECTION SUCCESSIVE EXAMINATIONS AFTER REPAIR REl lEF REQUEST HR E6 SYSTEM / COMPONENT (S) FOR WillCII REl.lEl IS REOUESTED:
All Class MC, Paragraphs IWE 2420(b) and IWE 2420(c) successive examination requirements for components found acceptable for continued service.
CODE REOUIREMENT(Sh Paragraphs IWE 2420(b) and IWE-2420(c) of the 1992 Edition,1992 Addenda of ASME Section XI, requires tnat when component examination results require evaluation of flaws,
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evaluation of areas of degradation, or repairs in accordance with Article IWE-3000," Acceptance Stasidards," and the component is found to be acceptable for continued service, the areas containing such flaws, degradation, or repairs shall be reexamined during the next inspection period listed in the schedule of the inspection program of Paragraph IWE 2411," Inspection Program A," or Paragraph IWE-2412," Inspection Program B," in accordance with Table IWE-2500-1, Examination Category E C.
CODE REOUIREMENT FROM WillCII l{El.lEF IS REOUESTED:
Reliefis requested from the requirement of Paragraphs IWE-2420(b) and IWE 2420(c) to perfonn successive examination of repairs.
jlASIS FOR REI,lEF:
10CFR50.55a was amended, as cited in the Federal Register (61FR41303), to require the use of the 1992 Edition,1992 Addenda, of Section XI, when performing containment examinations.
The purpose of a repair is t o restore lhe component to an acceptable condition for continued service in accordance witl' the acceptance standards of Article IWE-3000. Paragraph IWA-4150,
" Verification of Acceptability," requires the owner to conduct an evaluation of the suitability of the repair including consideration of the cause of failure, if the repair has restored the component to an acceptable condition, successive examinations are not warranted, if the repair was not suitable, then the repair does not meet code requirements and the component is not acceptable for continued service. Neither Paragraph IWB 2420(b),
Paragraph IWC-2420(b), nor Paragraph IWD-2420(b) requires a repair to be subject to successive examination requirementr. Furthennore, if the repair area is subject to accelerated degradation, it would still require augmented examination in accordance with Table IWE-2500-1, Examination Category E-C. The successive examination of repairs in accordance with Paragraphs IWE-2420(b) and IWE-2420(c) constitutes a burden without a compensating increase in quality or safety.
Docket Number 50 346 l.icense Number NPF 3 Serial Number 2506 Attachment Page 13 In SECY 96-080," Issuance of Final Amendment to 10CFR Section 50.55a to incorporate by Reference the AShiE Boiler and Pressure Vessel Code (AShiE Code), Sect'sn XI, Division 1, Subsection IWE and Subsection IWL," dated April 17,1996, response to comment # 3.3 states "The purpose ofIWE 2420(b)is to manage components found to be acceptable for continued service (meaning no repair or replacement at this time) as an Examination Category E C component... If the component had been repaired or replaced, then the more frequent examination would not be needed."
Reliefis requested in accordance with 10CFR50.55a(a)(3)(li). Compliance with the specified requirements of this section would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
The requirement to perform successive examinations following repairs has been removed in the rewrite of Subsection IWE of AShiE Section XI. This rewrite has been approved by AShiE and is scheduicd to be published in 1998.
AJ/ TERNATE EX AMINATION (Sh Successive examinations in accordanct with Paragraphs IWE 2420(b) and IWE-2420(c) are not required for repairs made in accordance with Article IWA-4000.
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Docket Number 50446 License Number NPF 3 Serial Number 2506 Attachment Page 14 CONTAINMENT INSPECTION llOLT TORQUE OR TENSION TESTING RELIEF REQUEST RR E7 SYSTEMS / COMPONENTS FOR WillCII RELIEF IS REOUESTED:
Class MC pressure retaining bolting.
CODE REOUIREMENT(S):
ASME Section XI,1992 Edition with the 1992 Addenda, Table IWE 25001 Examination Category E-0, Pressure Retaining Bolting, item 8.20.
CODE hEOUIREMENT FROM WillCil RELIEF IS REOUESTED:
Reliefis requested from ASME Section XI 1992 Edition,1992 Addenda, Table IWE-25001 Examination Category E 0, Pressure Retaining Bolting, item 8.20. Table IWE-2500-1 requires a bolt torque or tension test on bolted connections that have not been disassembled and reassembled during the inspection interval.
BASIS FOR REl.lEF:
10CFR50.55a was amended, as cited in the Federal Register (61FR41303), to require the use of the 1992 Edition,1992 Addenda, of ASME Section XI when performing containment examinations. Holt torque or tension testing is required on bolted connections that have not been disassembled and reassembled during the inspection interval. Detemiination of the torque or tension value would require that the bolting be un-torqued and then re-torqued or re tensioned.
Each containment penetration receives a 10CFR50 Appendix J, Type B test in accordance with the specified testing frequencies. As noted in 10CFR50 Appendix J, the purpose of Type B tests is to measure leakage of containment penetrations whose design incorporates resilient seals, gaskets, sealant compounds, and electrical penetrations fitted with flexible metal seal assemblies.
The perfonnance of the Type H test itself proves that the bolt torque or tension remains adequate to provide a leak rate that is within acceptable limits. The torque or tension value of bolting only becomes an issue if the leak rate is excessive. Once a bolt is torqued or tensioned, it is not subject to dynamic loading that could cause it to experience significant change. Appendix J testing and visual inspection is adequate to demonstrate that the design function is met. Torque or tension testing is not required for any other ASME Section XI, Class 1,2, or 3 bolted connections or their supports as part of the insersice inspection program.
Docket Number 50 346 License Number NPF-3 Serial Number 2506 Attachment Pagn 15 Reliefis requested in accordance with 10CFR50.55a(a)(3)(ii). Un torquinund subsequent retorquing of bolted connections which are verified not to experience unacceptable leakage through 10CFR50, Appendix J, Type B testing results in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
The requirement to perform bolt torque or tension tests has been removed in the rewrite of Subsection IWE of ASME Section XI. 'lhis rewrite has been approved by ASME and is scheduled to be published in 1998.
Al,TERNATIEXAMINATION(Sh Tne following examinations and tests required by Subsection IWE ensure the stmetural integrity and the leak-tightness of Class MC pressure retaining bolting, and, therefore, no additional alternative examinations are proposed:
(1) Exposed surfaces of bolted connections shall be visually examined in accordance with ree.uirements of Table IWE-2500-1, Examination Category E 0, Pressure Retaining Bolting, Item No. I!8.10, and (2) 11olted connections shall meet the pressure test requirements of Table IWE-25001, lixamination Category i? P, All Pressure Retaining Components, item E9.40.
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Docket Number 50e346 License Number NPF-3 Serial Number 2505 Attachment Page 16 CONTAINMENT INSPECTION VISUAL EXAMINATION PROCEDURES RELIEF REQUEST RR-E8 SYSTEAUCGMPONENT(S) FOR WillCil RELIEF IS REOl'ESTED:
All components subject to examination in accordance with Subsection IWE of the 1992 Edition, 1992 Addenda of ASME Section XI.
CODE REOUIREMENTS:
. Subarticle IWA-2210 provides requirements for visual examination procedures.
CODE 14 JUIREMENTS FROM WillCil RELIEF IS REOUF UE)1 Relief is requested from the provisions of Table IWA-2210-1, Visual Ev' iations. Table IWA-2210-1 requires direct visual VT-3 examinatic v he performe/
m illumination of 50fe, and at a maximum examination distar.~
4 feet. Ti n
.st be demonstrated to resolve a lower ue character height of 0.10. t :hes.
J.MSIS FOR RELIEF.1 10CFR50.55a was amended, as cited in the Federal Register (61FR41303), to require the use of the 1992 Edition,1992 Addenda of ASME Section XI when performing containment examinations. In addition to the regt.irements of Subsection IWE, this also imposes the requirements of the 1992 Edition,1992 Addenda of Subsectior. IWA for containment ex minations. For remote examination, this amendment to 10CFR50.55a permits the maximum direct examination distance specified in Table IWA-2210-1 be extended and the minimum illumination requirements specified in Table IWA-2210-1 decreased provided that the condithns or indications for which the visual examination is performed can be detected at the chosen distance and illumin:4.u. When perfonning a VT-3 examination of coated areas, IWE-3510.2, "VT-3 Visual Examinations on a Coated Areas," requires the area be inspected for evidence of flaking. blistering, peelhg, discoloration, and other signs of distrees.
The Davis Besse Nuclear Power Station (DbNPS) containment vessel is coated. Approximately 1P4 of the conminment surface is within the maximum 4 foot examination distance necessary to perform a direct visual VT-3 examination. The remainder must either be examined from scaffold or by remote exaininaion. In several areas, remote examination is difficult due to the proximity of the remote examin.d.on to tne containment surface. Distortion of the viewing area occurs when using opacal aids which magnify the area ofinterest. Many of these areas also do not cordain sufficient room to erect scafTold within 4 feet of the containment wssel. In other ueas, scaffold would re '.rict norma! access and egress routes for personnel working in conta,Laent.
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LDohnt Number 502346
- License Number NPF-3 :
. Serial Number 2506 2
- Amchment Page 17 Direct visual VT-3 examinations will be performed to the same distance and illumination:-
requirements as for remote visual' examinations. - That is, direct VT-3 examinations will be performed at distance and minimum illumination distances which'will detect the conditions or indications for which the visual examination is being performed.' The direct VT-3 examination will be equivalent to the remote examination. Both the direct VT-3 examinations and the remote VT-3 examinations will be carable of detecting flaking, blistering, peeling discoloration, or other
- ' signs of distress of coated c'entainment vessel.
As recognized in the amendment to 10CFR50.55a, the Table IWA 2210-1 VT-3 distance, illumination and qualification requirements are not necessary to identify conditions which may alTect the containment structural integrity. _ Use of the remote examination criter*a for direct visual exarninations will eliminate the need to build scaffold or ute remote examination when the.-
direct examination will detect the same conditions as would be identified through remote examination.
Reliefis requested in accordance with 10CFR50.55a(aX3Xii). Compliance with the specified requirements of this section would result in hardship or unusual difficulty without a compensating increase In the level of quality and safety.
The requirement to comply with IWA-2210 has been removeu.c the rewrite of Subsection IWE of ASME Section XI. This rewrite has been approved by ASME and it scheduled to be published in 1998.
Alternative Examination (sh i
VT-3 visual examinations will be performed under distance and illumination requirements necessary to detec. the conditions or indications for which the viseal examination is performed.
- The examination procedure will be demonstratcJ capable of detecting these condiC ns.
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Docket Nmr.ber 50-346 License Number NPF-3 Serial Number 2506 Attachment Page 18 C6hTAINMENT INSPECTION AUGMENTED EXhMINATION GRIDS RELIEF REQUEST RR E9 SYSTEM / COMPONENT (S) FOR W111CII RELIEF IS REOUESTED:
Surface areas subject to augmented examination in accordance with Subsection IWE of the 1992 Edition,1992 Addenda of ASME Section XI.
CODE REOUIREMENTS:
ASMt! Section, XI,1992 Ediuon,1992 Addenda, Subarticle IWE-2500(c)(3) requires one foot square grids be used when ultrasonic thickness measurements are performed on augmented examination surface areas. The number and location of the grids is determined by the Owner.
Subarticle IWE-2500(c)(4) requires the minimum wall thickness within each grid be determined, fJ)DE REOUIREMENTS FROM WIIICil RELIEF _IS REOUESTED:
Reliefis requested from using one foot square grids for augmented examination areas and the requirement to determine the minimum wall thickness within each grid.
J1 ASIS FOR RELIEF:
Subarticles IWE-2500(c)(3) and IWE 'FU(c)(4) of the 1992 Edition,1992 Addenda of ASME Section XI, require that the minimum thickness within each one foot square grid of surface areas requiring augmented examinatien be marked such that periodic reexamination of that location can be performed. Thickness readings are point reaomgs. Numerous readings are necessary to identify the minimum thickness within each grid. This only identifies the thinnest area. Periodic examination of the minimum thickness point -dy monitors that point. It may not be the area that is the most susceptible to accelerated degradation.
The attached Table RR-E9," Ultrasonic Thickness Measurements for Augmented Examination,"
provides the proposed alternative to t'.e one foot square grid area required by IWE-2500(c)(3).
Table RR-E9 requires examinat, ion at the grid line intersections. The grid line intersections may not exceed 12 inches and may be as small as 2 inches.
For a sample area of f 0 square feet, Table RR-E9 requires a minimum 100 locations be monitored. For a sample area of 50 square feet, IV!E-2500(c)(3) would require only 50 locations be monitored..In this.'nstance, utilizing Table RR-E9 monit:. more locations than required by iWE-2500(c)(3).
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- For sample areas greater than 100 square feet, Table RR-E9 requires that sufficient points be -
monitored 16 ensure at least a 95% confidence level that the thickness of the base metal is :
reduced by no more than 10% of the nominal plate thickness at 95% of the grid line intersections.
L Table RR-E9 also requires additional examinations when any measurements reveal wall i
thickness is reduced by more than 10% of the nominal plate thickness.
- For all examination areas, should the measurements at a grid line intersection reveal that the base material is reduced by more than 10% of the nominal plate thickness, Table RR-E9 requires the l
minimum wall thickness within each adjoining grid be determined. This is similar to the l
examination requirements ofIWE-2500(cX4) except that Table RR-E9 focuses resources on-areas which hr ve exhibited degradation rather than areas which have not exhibited degrada' tion.
L IThe Flow Accelerated Corrosion programs presently in place have proven that taking thickness -
readings at grid intersections are effective in monitoring *vall thinning of piping.
.t Reliefis requested in accordance with 10CFR50.55a(aX3Xii). Taking numerous utltrasonic thickness readings within a grid which had not exhibited degradation results in hardship or -
unusual difficulty without a compensating increase in the level of quality and safety.
The requirements of Table RR E9, except for note 1, have been incorporated into the rewrite of '
Subsection IWE of ASME Section XI. This rewrite has been approved by ASME and is
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scheduled to be published in 1998. Note 1 is contained within a draft ASME Code Case which has been approved by Subcommittee on Nuclear Inservice Inspection.
Alternathe Examination (sh Table RR-E9 will be used to determine examination requirements for ultrasonic th:ckness measurements of areas requiring augmented examination.
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Docket Number 50-346 License Number NPF-3 Serial Number 2506 Attachment Page 20 TAHLE RR-E9 ULTRASONIC TIIICKNESS h1EASUREMENTS FOR AUGMENTED EXAMINATIONS Augmented Examination Area Size Examination Requiremmts (Contiguous) 5100 square feet 100% of Grid Line intersections '23^'
> 100 square feet 100% of Grid Line Intersections '#da' Notes:
- 1. The number, location and size of areas to be examined shall be determined by the Owner.
2, cir!.1 line spacing shall not exceed 12 inches, and need not be less t;ian 2 inches.
- 3. Grid line spacing shall be selected such that a minimum of 100 measurements are obtained from within each augmented examination area, unless this requires selecting a grid line spacing ofless than 2 inches.
- 4. In lieu of examining 100% of the grid lit e intersections within the augmented examination area, an attemate examination plan may be developed as follows:
(a) A sample area from within the augmented examination area may be selected for examination. The location and size of the sample area shall be determined by the Owner, but shall consist of areas subject to the most severe sersice conditions within the larger augmen ' < amination area.100% of the grid line intersections within the sample area shall be v.samined, and grid line spacing shall be selected such that a minimum of 100 measurements are obtained from within the sample areas.
(b) If the sample area exceeds 100 contiguous square feet, the Owner may develop a sampling plan for examination of grid line intersections within the sample area.
Locations of ultrasonic thickness measurements to be taken at grid line intersections shall be selected at random throughout t' e sample area. The minimum number of measurements shall be 100, or shall be sufficient to ensure at least a 95% confidence level that the thickness of the base metal is reduced by no more than 10% of the nominal plate thickness at 95% of the grid line intersections within the sample area, w'hichever is greater.
(c) If any ultrasonic thickness measurements within the sample area reveal that the thickness of the base metal is reduced by more than 10% of the nominal plate thickness, all remaining grid line intersections within the sample area shall be examined, and additional UT examinations from outside of the sample area shall be required. These additional UT examinations shall be performed on another area from within the larger augmented examination area that is at least as large as the initial sample area. If any of these subsequent examinations reveal that the thickness of the base metal is reduced by more than 10% of the nominal plate thickness, additional areas from within the larger augmented examination area shall be examined i
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L Docket Number 50-346-License Number NPF-3 Serial Number 2506 Attachment Page 21 TABLE RR-E9 ULTRASONIC TillCKNESS MEASUREMENTS FOR AUGMENTED EXAMINATIONS Augmented Examination Area Size Examination Requirements (Contiguous) s100 square fe:.t 100% of Grid Line Intersections'JJA'
> 100 square feet IGO% of Grid Line Intersections i2aAo f
Notes:(Continued) until subsequent examinations of additional areas reveal no measurements where metal loss exceeds 10% of the nominal plate thickness, or until the entire augmented examination area has been examined.
- 5. When an ultrasonic thickness measurement performed at a grid line intersection reveals that the thickness of the base metal is reduced by more than 10% of the nominal plate thickness, the minimum wall thickness shall be deterrdned and located within each adjoining grid.
- 6. Measurements need not be obtained at locations where obstruct. ions interfere with grid line intersections.
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Docket Number 50-346-License Number NPF-3 Serial Number 2506 htachment Page 22 CONTAINMENT REPAlR/ REPLACEMENT PROGRAM RELIEF REQUEST RR-E10 SYSTEM / COMPONENT (S) FOR WillCII RELIEF IS REOUESTED:
All Class MC pressure retaining components.
CODE REOUIREMENTS:
ASME Section XI,1992 Edition,1992 Addenda, Subsection IWE CODE REOUIRE)1ENTS FROM WillCII RELIEF IS REOUESTED:
Implementation of the 1992 Edition,1992 Addenda of ASME Section XI for examination of Class MC components requires the use of Subsection IWA-4000 of the 1992 Edition,1992 Addenda of ASME Section XI for repairs and replacements to Class MC components.
HASIS FOR RELIEF:
In the Federal Register dated August 8,1996,(61FR41303), the NRC amended its regulations to incorporate the 1992 Edition,1992 Addenda of ASME Section XI when performing containment y
examinations. In addition to the requirements of Subsection IWE, this also imposes the requirements of the 1992 Edition,1992 Addenda of Subsection IWA-4000," Repair and Replacement," for containment repairs and replacements.
Toledo Edison holds a National Board Nuclear Repair Certificate of Authorization for repairs / replacements to Class 1,2,3, and MC components. This Certificate of Authorization is based on the Davis Besse Nuclear Power Station (DBNPS) Repair / Replacement program which is written to the requirements of the 1986 Edition, No Addenda, of ASME Section XI. This program aquires that repairs and replacements to the containment vessel meet its design specifications and Construction Code requirements. T his ensures that the original integrity anl quality of the containment vessel will be maintained during repair / replacement activities.
Meeting both the 1986 Ectition, No Addenda, and the 1992 Edition,1992 Addenda of ASME Section XI requires the maintenance of two separate repair and replacement programs (one for the IWB, IWC, and IWD components per the 1986 Edition, No Addenda of ASME Section XI and one for the containment vessel per the 1992 Edition,1992 Addenda of ASME Section XI).
Duplicate records to demonstrate compliance with the 1986 Edition,No Addenda, and the 1992 Edition,1992 Addenda, will also be required. This duplication of programs and records increases the man-hours necessary to maintain the D*1NPS Repair /Repircement Program without
- providing any increase in quality of containment vessel repairs /repicen ents.
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Docket Number 50-346 License Number NPF-3 Serial Number 2506 Attachment Page 23 Reliefis requested in accordance with 10CFR50.55a(a)(3)(1). The DBNPS repair / replacement program ensures that the original integrity and quality of the containment vessel is maintained du'ing repair /replacem:nt activities, ALTERNATIVE EXAMINATION:
The DBNPS Repair /Replaceraent Program, written to the requirements of 1986 Edition, No Addenda of ASME Section XI, will be used for repairs and replacements to the containment g
vessel, Preservice examinations will be conducted in accordance with the requirements of Subsection IWE of the 1992 Edition,1992 Addenda of ASME Section XI.
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