ML20210P918
| ML20210P918 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 08/10/1999 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20210P896 | List: |
| References | |
| NUDOCS 9908130107 | |
| Download: ML20210P918 (19) | |
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UNITED STATE i j, M]
NUCLEAR REGULATORY COMMISSION
'C W ASHINGTON, D.C. 20555-0001 j
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EVALUATION OF RELIEF REQUESTS l
IMPLEMENTATION OF SUBSECTIONS IWE AND IWL OF ASME SECTION XI FOR CONTAINMENT INSPECTION j
CAROLINA POWER AND LIGHT COMPANY'S BRUNSWICK STEAM ELECTRIC PLANT, UNIT NOS.1 AND 2 1
DOCKET NOS. 50-324 AND 50-325 INTRODUCTION j
By letter dated October 28,1998 (Ref.1), the licensee, Carolina Power & Light (CP&L)
Company, submitted relief request Nos. CIP-01 to CIP-18, seeking relief from some of the ASME Code,Section XI, Subsections IWE and IWL requirements for Brunswick Steam Electric Plant (BSEP), Unit Nos.1 and 2. These relief requests apply to the containment examinations that will be initiated by CP&L during BSEP, Unit 1 Refueling Outage 12, which is scheduled to begin in February 2000.
Pursuant to 10 CFR 50.55a(b) and (g), inservice inspection of containment must meet the j
requirements of the 1992 Edition,1992 Addenda of ASME Code,Section XI, Subsections IWE and IWL. Pursuant to 10 CFR 50.55a(g)(6)(ii)(B), the first period containment examinations must be completed by September 9,2001. Alternatives to the requirements of 10 CFR 50.55a(g) may be authorized under 10 CFR 50.55a(a)(3), if (i) the proposed alternative provides and acceptable level of quality and safety, or (ii) compliance with the specific requirement of the Code would result in hardship or unusual difficulty without compensating increase in the level of quality and safety. By letter dated May 4,1999 (Ref. 2), CP&L revised relief requests CIP-03, CIP-04, CIP-05, CIP-07, CIP-10, CIP-16, and CIP-17 to request relief pursuant to 10 CFR 50.55a(a)(3)(i) rather than 10 CFR 50.55a(a)(3)(ii).
The staff evaluation addresses the merits of the requests for relief (Ref.1) proposed by the licensee, CP&L, for BSEP Unit Nos.1 and 2.
EVALUATION Relief Reouest No. CIP-01 Code Reouirement: Table IWE-2500-1, Examination Category E-D, item E5.30 requires a VT-3 visual examination of each containment moisture barrier.
Licensee's Proposed Alternative: In accordance with 10 CFR 50.55a(a)(3)(i), the licensee proposed to implement an alternative examination method and frequency to those specified in Table 2500-1, Examination Category E-D, item E5.30. CP&L proposed to perform a general Enclosure 9908130107 990810 PDR ADOCK 05000324 G
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. - visual examination of the containment moisture barriers once each Inspection Period (i.e.,
three examinations in a 10-year period).
. The licensee states:
CP&L will examine the containment moisture barriers once each inspection Period (i.e., three examinations in a ten year period). The general visual examination performed by CP&L is a thorough examination of the accessible surface areas and is performed by qualified and properly trained examiners. The
- examination methods outlined in this procedure will be written to be consistent with the methods approved in the rewrite of Subsection tWE (1998 Edition) and will be approved by a Registered Professional Engineer. Personnel performing these visual examinations will be certified as ANSI /ASME N45.2.6 examiners in accordance with a CP&L procedure.
' Staff Evaluation:
The licensee proposes to use an alternative examination method and frequency to those specified in Table 2500-1, Examination Category E-D, item E5.30. As noted by the licensee, the more stringent requirements outlined for a VT-3 visual examination ge not appropriate for the examination of containment moisture barriers, since the VT-3 visual' examination requirements, outlined in IWA-2210, were written primarily for detecting flaws in metallic i
components (e.g., welds, supports). The licensee states, "The containment moisture barriers, installed at BSEP, are made of a high density silicone elastomer material and do not perform a pressure retaining or load bearing function. Because of its non-metallic composition, this materialis not subject to the same degradation mechanisms as an item made of a metallic material. Therefore, a VT-3 visual examination of the containment moisture barriers is not warranted nor would it provide a compensating increase in quality and safety."
The ASME Main Committee and the Board of Nuclear Codes and Standards have approved the revision of Subsection IWE to eliminate the requirement for performing a VT-3 visual examination of containment moisture barriers. This revision of Subsection IWE was published in the 1998 Edition of the ASME Code,Section XI. The altemative examination method proposed by the licensee is consistent with this revision of Subsection IWE. The staff finds the proposed attemative adequate for detecting and correcting potential degradation of the
- containment moisture barriers. Therefore, the licensee's proposed altemative is authorized pursuant to 10 CFR 50.55a(a)(3)(i) on the basis that it provides an acceptable level of quality and safety.
Relief Recuest No. CIP-02
- Code Reauirement:
i IWE-3515.1 requires that bolting materials be examined in accordance with the material specification for defects that may cause the bolted connection to violate either the containment leaktightness or structural integrity.
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f' Licensee's Proposed Alternative:
In accordance with 10 CFR 50.55a(a)(3)(i), the licensee proposed to implement an alternative examination method to that specified in IWE-3515.1.
The licensee states:
Pressure retaining bolting shall be examined for conditions which may cause the bolted connection to violate either the containment leak-tightness or structural integrity. Examples of such conditions are: (1) bent, twisted, fractured, or deformed bolts, studs, nuts or washers, (2) missing or loose bolts, studs, nuts or washers, and (3) degraded coating on bolting surfaces accompanied by damage or degradation of the bolting material. Conditions identified during the examination will be evaluated. Those conditions that cause the bolted connection to violate either the containment's leak-tightness or structural integrity will be corrected by a repairireplacement activity prior to returning the component to sen/ ice.
Paragraph IWE-3515.1 refers the user back to the applicable material specification for the examination and acceptance standard for bolting materials. The bolted connections associated with the primary containment structure have been in service for over twenty years. Applying manufacturing standards for new botting to these bolted connections is not warranted, nor does it provide a compensating increase in quality and safety.
Staff Evaluation:
The licensee proposes to use an alternative examination method to that specified in lWE-3515.1. In its basis for requesting relief, the licensee asserts that applying a manufactunng standard for new bolting to bolted connections that have been in service for over 20 years is unwarranted. The ASME Main Committee and the Board of Nuclear Codes and Standards have also determined that referring the user back to the material specification was not appropriate and.has approved the rewrite of Subsection IWE, which eliminated the requirement for examining bolting materials in accordance with the material specification. The staff finds the proposed alternative adequate for detecting and correcting those conditions that cause the bolted connection to violate either the containment's leaktightness or structural integrity. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i) on the basis that it provides an acceptable level of quality and safety.
Relief Reauest No. CIP-03 Code Reauirement:
IWE-1231(a)(3) requires that single-welded butt joints remain accessible from the weld side for the life of the plant.
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Licensee's Proposed Altemative:
In accordance with 10 CFR 50.55a(a)(3)(i), the licensee proposed to implement an alternative to the requirement specified in IWE-1231(a)(3). As an altemative, CP&L has proposed to ensure that single-weld butt joints are included in the requirement to maintain at least 80% of the pressure-retaining boundary, as defined in Table IWE-2500-1, Examination Category E-A, accessible for examination for the life of the plant.
Staff Evaluation:
The licensee proposes to use an altemative examination method to that specified in IWE-1231(a)(3), which requires that single-welded buttjoints remain accessible from the weld side for the life of the plant. IWE-1231(a)(3) was established to assure that the examination specified in Examination Categories E-B and E-F could be met; however, the staff has determined that degradation of base metal, rather than welds, is the primary concem for aging containments. Thus,'10 CFR 50.55a has been modified to make inspection of welds per Examination Categories E-B and E-F optional and, as such, the requirement specified in IWE-1231(a)(3) is no longer necessary. Therefore, relief is not required.
Relief Reauest No. CIP-04 Code Reauirement:
1 Table IWE-2500-1, Examination Category E-D (item Nos. E5.10 and E5.20) requires a VT-3 visual examination of seals and gaskets during the inspection interval. Seals and gaskets are to be examined for wear, damage, erosion, tear, surface cracks, or other defects that may-violate the leaktight integrity. Defective items will be repaired or replaced.
Licensee's Proposed Aftemative:
In accordance with 10 CFR 50.55a(a)(3)(i), the licensee proposed to implement an altemative to the requirement specified in Table IWE-2500-1, Examination Category E-D (Item Nos. E5.10 and E5.20). As an attemative, CP&L has proposed to verify the leaktightness of the seals and gaskets in accordance with the testing requirements specified in 10 CFR Part 50, Appendix J.
The licensee states:
Performance of the visual examination of the seats or gaskets would require disassembly and re-assembly of the mechanical connection for those penetrations (e.g., Personnel Al:iock-to-Drywell, Drywe'l Head Access Hatch) that are not routinely disassembled during a refueling outage. The seals or gaskets associated with these penetrations are also not accessible for examination when the connection is assembled. For this reason, the connection would require disassembly for the sole purpose of performing the visual examination. Since these connections are periodically Type B tested in l
accordance with 10 CFR 50, Appendix J to verify their leak-tight integrity, CP&L
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considers the physical wear of the components and the possibility of component j
damage that could be associated with the disassembly and re-assembly activity I
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. associated with the disassembly and re-assembly activity unwarranted and a hardship without a compensc'ing increase in que ty and safety.
c Staff Evaluation:
The licensee proposes to use the existing 10 CFR Part 50, Appendix J, Type B testing as a verification of seal and gasket integrity, rather than disassembling the subpct components for the sole purpose of examination.
Performing the VT-3 examinations on the subject gaskets and seals would require disassembly and reassembly of the mechanical connection for those penetrations that are not routinely disassembled during a refueling outage. The ASME Main Committee and the Board of Nuclear Codes and Standards have also determined that a VT-3 examination of the seals and gaskets is no longer warranted. Both organizations have approved the rewrite of Subsection IWE to delete
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the requirement for performing a VT-3 examination of the seals and gaskets. This rewrite of Subsection IWE was published in the 1998 Edition of the ASME Code,Section XI. Requiring the licensee to disassemble components for the sole purpose of inspecting seals and gaskets would place a significant hardship on the licensee without a compensating increase in quality and safety.
The licensee will verify the leaktight integrity of seals and gaskets, utilized on penetrations, that are required to assure containment leaktight integrity, in accordance with the applicable requirements of 10 CFR Part 50, Appendix J. Therefore, the proposed alternative is authorized pursuant to 10 CFR 50.F51(a)(3)(ii) on the basis that compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. The proposed testing provides reasonable assurance of containment leaktight integrity.
Relief Reauest No. CIP-05 Code fleauirement:
Paragraph IWE-2420(b) requires that, when examination results require evaluation of flaws, evaluation of areas of degradation, or repairs in accordance with IWE-3000, 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. The reexaminations are to be performed in accordance with Examination Category E-C and at the schedule specified in the inspection requirements of IWE-2411 or IWE-2412.
Paragraph IWE-2420(c) states that, when the reexaminations required by Paragraph IWE-420(b) reveal that the flaws, areas of degradation, or repairs remain essentially unchanged for three consecutive inspection periods, the areas containing such flaws, degradation, or repairs no longer require augmented examination in accordance with Table IWE-2500-1, Examination Category E-C.
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. Licensee's Proposed Attemative:
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The licensee proposed an attemative to performing successive examinations on repairs.
The licensee states:
During the First Containment inspection Interval, CP&L will perform the repair of l
degraded areas in accordance with an approved Repair / Replacement Program.
For degraded areas that are accepted by engineering evaluation, the applicable -
successive inspection requirements specified in paragraph IWE 24.20 will be met.
l Staff Evaluation:
l IWB-2420(b), lWC-2420(b), and IWD-2420(b) do not require the successive inspection of repairs as required in IWE-2420(b). Additionally, when repairs are complete, IWA-4150 requires licensees to evaluate the suitability of the repair. When a repairis required because an item fails, the evaluation will consider the cause of failure to ensure that the repair is suitable. Considering that the failure mechanism is identified and corrected as required and that the repair receives presenrice examinations, as required, the proposed altemative will provide reasonable assurance of structuralintegrity. Performance of the successive examinations presents an unnecessary burden on the licensee without a compensating increase in safety. -Therefore, the licensee's proposed attemative is authorized pursuant to 10 CFR 50.55a(a)(3)(ii) on the basis that compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. The proposed testing provides reasonable assurance of containment leaktight integrity.
Relief Reauest No. CIP-06 Code Reauirement:
i Table IWE-2500-1, Examination Category E-G (Item No. E8.10), requires a VT-1 visual examination of 100% of each bolted connection during the inspection interval.
l Licensee's Proposed Attemative:
During the first containment inspection interval, CP&L will perform a general visual examination of each pressure-retaining bolted connection once per inspection interval.
The licensee states:
The bolted connection [s] will be examined in their "as-found" condition and will not be disassembled for the sole purpose of performing the general visual examination. If an area is determined to be suspect during the general visual examination, CP&L will perform a detailed visual examination to determine the '
magnitude and extent of the suspect areas. If required, CP&L will disassemble the bolted connection to. support the performance of the detailed visual examination.
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- l Staff Evaluation:
l The licensee has committed to conduct a thorough examination of the pressure-retaining bolting by qualified and properly trained examiners. Both the general and/or detailed examination will be performed in accordance with a procedure that will specify sufficient illumination and resolution for detecting degradation. The procedure outlining these controls will be reviewed and approved by a Registered Professional Engineer. Furthermore, personnel performing these visual examinations will be certified as ANSI /ASME N45.2.6 examiners in accordance with a CP&L procedure. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i) on the basis that it provides an acceptable level of quality and safety.
Relief Reauest No. CIP-07 Code Reouirement:
Table IWE-2500-1, Examination Category E-G (Item No. E8.20), requires a torque or tension test of bolted connections that have not been disassembled and reassembled during the inspection interval.
Licensee's Proposed Alternative:
The licensee proposed to perform alternative examinations in lieu of the required bolt torque or tension test.
The licensee states:
During the First Containment inspection Interval, CP&L will verify the leak-tight integrity of bolted connections that are required to assure containment leak-tight integrity in accordance with the applicable requirements of 10 CFR 50, Appendix J.
Staff Evaluation:
The Code requires that pressure-retaining bolting that has not been disassembled and reassembled during the inspection interval be torque or tension tested. This examination is used to aid in the determination that a leaktight seat exists and that the structuralintegrity of the subject bolted connections is maintained. The licensee proposed to use the 10 CFR Part 50, Appendix J, Type B test as an alternative to the Code requirement to verify the integrity of penetrations with bolted connections.
The Appendix J, Type B test, to verify the containment pressure seal, will provide an acceptable level of quality and safety. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
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' Relief Reauest No. CIP-08 Cqde Reauirement:
Article IWA-6000 requires the owner to prepare and submit the Owners Report for Inservice Inspection, Form NIS-1, and the Owners Report for Repair or Replacements, Form NIS-2.
Licensee's Proposed Afternative:
Pursuant to 10 CFR 50.55a(a)(3)(i), the licensee proposed to implement the alternative requirements outlined in ASME Code Case N-532, " Alternative Requirements to Repair and Replacement Documentation Requirements and Inservice Summary Report Preparation and Submission as required by IWA-4000 and IWA-6000."
The licensee states:
Accordingly, CP&L will prepare and submit the Owners Activity Report for Inservice inspection, Form OAR-1 and the Repair / Replacement Certification Record, Form NIS-2A in accordance with the alternative requirements of ASME Code Case N-532. The other applicable requirements of Article IWA-6000 of the ASME Code,Section XI will be met.
Staff Evaluation:
The staff reviewed the proposed alternative documentation requirements of Code Case N-532 and determined that, although the required forms have changed, the information required by the Code remains available for review. Code Case N-532 would require preparation of the Repair / Replacement Certification Record, Form NIS-2A. The completed form NIS-2A will be certified by an Authorized Nuclear Inservice inspector (ANil) as defined in ASME Code,Section XI, IWA-2130, and will be maintained by the owner. Furthermore, the owner's activity report form, OAR-1, will be prepared and certified by an ANil upon completion of each refueling outage. The OAR-1 form will contain an abstract of applicable examinations and tests, a list of item (s) with flaws or relevant conditions that require evaluation to determine acceptability for continued service, and an abstract of repairs, replacements and corrective measures performed as a result of unacceptable flaws or relevant conditions. Hence, the information provided in the documentation required by Code Case N-532 can be used to assess the safety implications of Code activities performed during an outage. A review using the information as prescribed by the Code Case will, therefore, provide the same or improved level of quality and safety as reviews that may be conducted with the Code reporting requirements. In addition, more detailed information may be requested by the staff if it is deemed necessary. Therefore;the licensee's proposed alternative is authorized on the basis that it provides an acceptable level of quality and safety pursuant to 10 CFR 50.55a(a)(3)(i).
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. Relief Reauest No. CIP-09 Code Recuirement:
Paragraph IWA-4220(a) requires welding, including brazing, to be performed in accordance with i
Welding Procedure Specification (WPS) that has been qualified by the owner or repair organization in accordance with the requirements of the Codes in the Repair Program specified by paragraph IWA-4140.
Licensee's Proposed Altemative:
During the first containment inspection interval, CP&L will implement the alternative requirements of ASME Code Case N-573 [" Transfer of Procedure Qualification Records Between Owners,Section XI, Division 1").
' Staff Evaluation:
Code Case N-573 essentially allows the use of a welding or brazing procedure qualification record (POR) qualified by one owner to be used by another owner for the development of the WPS. The specific requirements listed in Code Case N-573 will be met by the Owner that performed the procedure qualification, and by the Owner intending to use the POR. These requirements are:
l (1)
The owner that performed the procedure qualification test will certify, by signing the POR, that testing was performed in accordance with Section IX.
(2)
The owner that performed the procedure qualification test will certify, in writing, that the procedure qualification was conducted in accordance with a quality assurance program that satisfies the requirements of IWA-1400.
(3)
The owner accepting the ' completed POR will accept responsibility for obtaining any additional supporting information needed for WPS development.
(4)
The owner accepting the completed POR will document, on each resulting WPS, the parameters applicable to welding. Each WPS will be supported by all necessary PQR's.
(5)
The owner accepting the completed POR will accept responsibility for the PQR.
' Acceptance will be documented by the owner's approval of each WPS that references the POR.
(6)
The owner accepting the completed POR will demonstrate technical competence in application of the received POR by completing a performance qualification test using the parameters of a resulting WPS.
(7)
The owner may accept and use a POR only when it is received directly from the Owner that certified the PQR.
. (8)
Use of this Code Case will be shown on the NIS-2 form documenting welding or brazing.
The licensee has committed to comply with the requirements specified in Code Case N-573. The staff concludes that the proposed alternative provides an acceptable level of quality and safety.
Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
Relief Reauest No. CIP-10 Code Reauirement:
Subarticle IWA-2300 provides the qualifications for nondestructive examination (NDE) personnel.
Licensee's Proposed Alternative:
In accordance with 10 CFR 50.55a(a)(3)(i), the licensee has requested approval to use alternative requirements for the qualification of visual (VT-2) examination personnel to those specified in paragraph IWA-2300. CP&L proposed to implement the alternative requirements of Code Case N-546, " Alternative Requirements for Qualification of VT-2 Examination Personnel."
Staff Evaluation:
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The Code requires that VT-2 visual examination personnel be qualified to levels of competency comparable to those identified in ANSI N45.2.6. The Code also requires that the examination personnel be qualified for near and far distance vision acuity. In lieu of the Code requirements, the licensee proposed to implement Code Case N-546 for personnel performing VT-2 visual examinations.
The qualification requirements in Code Case N-546 are not significantly different from those for VT-2 visual examiner certification. To ensure proper implementation of Code Case N-546, CP&L has committed to develop procedural guidelines for performing consistent and quality leakage examinations. The licensee has also committed to document and maintain records to verify the qualification of personnel performing these examinations. The staff concludes that the proposed alternative provides an acceptable level of quality and safety. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
Relief Reauest No. CIP-11 Code Reauirement:
Table IWE-2500-1, Examination Category E-A (Item Nos. E1.12 and E1.20), requires a visual (VT-3) eAdmination of the accessible surface areas of the containment vessel during the inspection interval.
Licensee's Proposed Alternative:
To satisfy the requirements of Examination Category E-A (Item Nos. E1.12 and E1.20),
CP&L will perform a general visual examination of the accessible surface areas of the
containment during the First Containment inspection Interval. When evidence of degradation is detected by the examiners, CP&L will perform a detailed visual examination. If a detailed visual examination cannot be performed, an engineering evaluation approved by a Registered Professional Engineer will be provided which will
[ evaluate) the suspect area. To ensure the controls and techniques are adequate for detecting evidence of degradation, a Registered Professional Engineer will periodically witness the performance of these examinations. In addition, CP&L will examine the accessible surface areas of the Vent System once per Inspection Period.
This proposed alternative examination method has been evaluated by CP&L, and CP&L has determined that the implementation of the alternative requirement will provide an acceptable level of quality and safety for the following reasons:
CP&L will examine the accessible surface areas of the Vent System (Item No. E1.20) once each Inspection Period (i.e., three exarninations in a ten year period). Performing a general visual examination of the accessible surface areas at this frequency would detect and correct potential degradation prior to failure and is considered an enhancement to the requirements specified in the ASME Code,Section XI,1992 Edition with the 1992 Addenda. The ASME Code,Section XI only requires a visual examination to be performed once during this same time period.
The visual (VT-3) examination specified in Examination Category E-A requires that the visual examination and qualification of the examiners meet the applicable requirements of Subarticles IWA-2200 and IWA-2300, respectively. The requirements specified in these subarticles were developed for detecting flaws in metal components and, for this reason, are more stringent than those that would be required for the detection of degradation such as corrosion. Since corrosion of the base metalis the primary issue of concern at BSEP, CP&L has established controls for the performance of a general visual examination that will detect age related mechanisms that may affect the structural integrity and/or leak-tightness of the containment. Thus, the general visual examination performed by CP&L will be a thorough examination of the accessible surface areas and will be performed by certified and properly trained examiners. If an area is determined to be suspect during the general visual examination, CP&L will take additional actions to ensure the suspect area is properly characterized for evaluation.
The general visual examination will be performed in accordance with a CP&L approved procedure. The examination methods outlined in this procedure will be consistent with the methods approved in the rewrite of Subsection IWE,1998 Edition and will be approved by a Registered Professional Engineer. These approved methods will delineate the necessary controls for ensuring these examinations are performed in a manner sufficient to detect evidence of degradation. To assure these methods are sufficient to detect evidence of degradation, a Registered Professional Engineer w;ll periodically witness the performance of these examinations.
Whr 1 evidence of degradation is detected by the examiner, CP&L will perform a detailed vh d examination to ensure the suspect area is properly characterized for evaluation. If trw detailed visual examination cannot be performed (e.g., access limitation), CP&L will
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I evaluate the acceptability of the suspect area. The engineering evaluation will assume l
the suspect area is inaccessible and will address the requirements outlined in 10 CFR 50.55a(b)(2)(x)(A). This engineering evaluation will be approved by a Registered Professional Engineer.
The general and/or detailed visual examination will be performed by certified and properly trained personnel. Personnel performing these visual examinations will be certified in accordance with ANSI /ASME N45.2.6 and a CP&L procedure. This level of certification will ensure the capability and visual acuity of the examiners [are] sufficient to detect evidence of potential degradation of the containment's accessible surface areas. Prior to performing the examinations, the examiners will also be required to successfully complete CP&L approved training (i.e., training developed by the Electric Power Research Institute (EPRI) or equivalent) on the proper techniques for examining components and items subject to the requirements of Subsection IWE. In addition, the examiners will receive site specific training regarding the methods outlined in the approved plant procedure. The site specific training will be conducted under the direction of a Registered Professional Engineer and will be held at the beginning of each subsequent inservice inspection used to satisfy the applicable requirements of Subsection IWE. Successful completion of the above training will ensure the examiners have a basic working knowledge of the components being examined and the types of degradation to be detected.
The more stringent requirements outlined for a VT-3 visual examination are not necessary for the examination of accessible surface areas of the containment vessel. The VT-3 visual examination requirements, outlined in IWA-2210, were written primarily for detecting flaws in metallic components (e.g., welds, supports). As defined in IWA-2213, a VT-3 visual examination is conducted to determine the general mechanical and structural condition of components and their supports. This examination is accomplished by verifying parameters such as clearances, settings, and physical displacement; and to detect discontinuities and imperfections (e.g., loss of integrity at bolted or welded connections). Since the surface areas of the containment are not subject to conditions that require the more stringent requirements outlined in Subarticles IWA-2200 and IWA-2300, a visual (VT-3) examination is not warranted nor would it provide a compensating increase in quality and safety. Degradation mechanisms, such as corrosion, can easily be detected by a general visual examination program. The program developed by CP&L will detect these types of mechanisms. To ensure the controls and techniques meet this expectation, the procedure gwerning the general visual examination methods will be, te iewed and approved by e. Registered Professinnal Engineer.
The ASME Main Committee and the Board of Nuclear Codes and Standards have also determined that a VT-3 visual examination of the containment's accessible surface areas is not warranted. Both organizations have approved the rewrite of Subsection IWE which eliminated the requirement for performing a VT-3 visual examination of these items. This rewrite of Subsection IWE was published in the 1998 Edition of the ASME Code,Section XI. The alternative examination method proposed by CP&L is consistent with the approved rewrite of Subsection IWE and will provide an acceptable level of quality and safety.
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. Staff Evaluation:
l Table IWE-2500-1, Examination Category E-A (ltem Nos. E1.12 and E1.20), requires a visual (VT-3) examination of the accessible containment surface areas (E1.12) and accessible surface areas of the Vent System (E1.20) during the inspection interval. The visual (VT-3) examination specified in Examination Category E-A requires that the visual examination meet the requirements of Subarticle IWA-2200. The requirements specified in Subarticle IWA-2200 were developed for detecting flaws in metal components and, as a result, are more stringent than requirements for detecting degradation such as corrosion. The licensee has committed to perform a general visual examination of the accessible surface areas of the containment (Item No. E.12) during the First inspection Interval and the accessible surface areas of the Vent System (Item No. E1.20) once per inspection period using certified and properly trained examiners with examination methods consistent with the methods approved in the rewrite of a
Subsection IWE,1998 Edition. Furthermore, a Registered Professional Engineer will approve the examination methods to ensure that they are sufficient to detect evidence of degradation.
Although the staff finds that a general visual examination is generally sufficient to examine accessible surface areas of the containment vessel, the staff finds that Items E1.12 (accessible surface areas of the containment vessel pressure retaining boundary) and E1.20 (accessible surface areas of the vent system in BWRs) include wetted surfaces of submerged areas and flow channeling devices within containment vessels. These areas are key locations susceptible to degradation mechanisms that could impair the leaktight integrity of the containment. The general visual examination proposed by the licensee does not provide the same requirements for the qualification of examining personnel as those specified for VT-3. It is also unclear whether the general visual examination is sufficient to detect the degradation mechanisms in these highly susceptible areas of degradation. Thus, the staff is unable to conclude that an acceptable level of safety is provided in the use of a general visual examination in lieu of a VT-3 examination for these susceptible areas of the containment.
Therefore, Relief Request No. CIP-11 is denied for (1) the wetted surfaces of submerged areas of the containment vessel pressure retaining boundary and (2) vent system in BWRs. For the remaining accessible surface areas of the containment vessel pressure-retaining boundary, the staff concludes that the use of a general visual examination is sufficient to detect the type of degradation that might occur in these areas and, thus, provides an acceptable level of quality and safety.
The licensee's proposed alternative in CIP-11 for the containment vessel pressure-retaining boundary, except for (1) the wetted surfaces of submerged areas of the containment vessel pressure-retaining boundary and (2) vent system in BWRs, is, therefore, authorized pursuant to 10 CFR 50.55a(a)(3)(i) on the basis that it provides an acceptable level of quality and safety.
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. Relief Reauest No. CIP-12 l
b-Code Reauirement:
IWE-2200(g) requires that when paint or coatings are reapplied, the condition of the new paint or coating will be documented in the preservice examination records.
Licensee's Proposed Alternative:
In accordance with 10 CFR 50.55a(a) (3)(i), Carolina Power & Light (CP&L) Company is requesting approval to implement an alternative to the documentation requirements specified in IWE-2200(g). CP&L proposes to inspect and document the reapplied
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coatings (including paints) in accordance with the BSEP's Protective Coatings Program.
Staff Evaluation:
In the basis for the relief request, the licensee states that it has established the appropriate controls for the coating applications associated with the interior and exterior surfaces of the i
Primary Containment structure. These controls are contained in a plant procedure that covers (1) materials to be used, (2) application methods, (3) inspection, (4) personnel qualification, (5) repair, and (6) documentation. The plant procedure is written to comply with the applicable requirements of Regulatory Guide 1.54, ANSI N5.12, ANSI N101.2, and ANSI N101.4. The licensee's Protective Coatings Program provides a conservative approach to the inspection and documentation of new coatings and as such, the staff concludes that the proposed attemative provides an acceptable level of quality and safety. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
Relief Reauest No. CIP-13 Code Reauirement:
1 IWE-2500(b) rcquires that when paint or coatings are to be removed, the paint or coatings will be
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visually examined in accordance with Table IWE-2500-1 prior to removal.
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Licensee's Proposed Alternative-l in accordance with 10 CFR 50.55a(a)(3)(i), Carolina Power & Light (CP&L) Company is requesting approval to implement an alternative to the visual examination specified per IWE-2500(b). CP&L proposes to inspect the coatings, including paints, in accordance with the BSEP's Protective Coating Program.
Staff Evaluation:
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The purpose of performing the visual examination per IWE-2500(b) is to identify any evidence of base metal degradation prior to removal of the coating or paint. As an alternative to the i
requirements of IWE-2500(b), the licensee has proposed to inspect the coatings, including paints, using its protective coating program. In the basis for requesting relief, the licensee states i
o
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. that its protective coating program has been written to comply with the applicable requirements of Regulatory Guide 1.54, ANSI N5.12, ANSI N101.2, and ANSI N101.4. Section 6 of ANSI N101.4 requires stringent inspection of the entire completed coating work by qualified coating inspection personnel, as well as quality assurance documentation. To assure the integrity of the base metal prior to the application of a new coating, the licensee has established a hold point in the l
procedure. The licensee states that degradation of the base metal would be identified at this time and that corrective actions would be initiated prior to the reapplication of the coating or paint.
Based upon the licensee's verification of sound base metal prior to application of new coatings.
the staff considers the proposed alternative, as stated by the licensee, adequate for protecting the containment surfaces. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i) on the basis that it provides an acceptable level of quality and safety.
L Relief Reauest No. CIP-14 l
Code Reauirement:
Table IWL-2500-1, Examination Category L-A (Item Nos. L1.11 and L1.12), IWL-2310, and IWL-2510 requires a visual (VT-3C) examination of the accessible areas and a visual (VT-1C) examination of suspect areas.
Licensee's Proposed Alternative:
1 in accordance with 10 CFR 50.55a(a)(3)(i), Carolina Power & Light (CP&L) Company is requesting approval to implement alternative examination methods to those specified in j
Table IWL-2500-1, Examination Category L-A (Item Nos. L1.11 and L1.12), IWL-2310, and IWL-2510. CP&L proposes to perform a general visual examination of the accessible areas and a detailed visua1 examination of those areas determined to be suspect.
I Staff Evaluation:
The visual examination of accessible areas (VT-3C) and suspect areas (VT-1C) per Table l
IWL-2500-1, Examination Category L-A (Item Nos. L1.11 and L1.12), IWL -2310, and IWL-2510 requires that the visual examination and qualification of the examiners meet the applicable requirements of IWA-2210 and IWA-2300. However, the requirements specified in IWA-2210 and -2300 were developed for detecting flaws in metal components and, as a result, are more stringent than those that would be required for the detection of degradation on concrete structures. As such, the requirements of IWA-2210 and -2300 have been removed from Subsection IWL in the 1997 Addenda.
As an alternative, the licensee has committed to examination methods that are consistent with the methods approved in the rewrite of Subsection IWL (1997 Addenda) and that have been approved by a Registered Professional Engineer.
The licensee states:
These approved methods will delineate the necessary controls for ensuring these examinations are performed in a manner sufficient to detect evidence of degradation.
. When evidence of degradation is detected by the examiner, the procedure also requires a detailed visual examination to be performed and compared to established reporting and acceptance criteria. The reporting criteria, along with acceptance criteria, was approved by a Registered Professional Engineer and is consistent with the guidance outlined in the American Concrote Institute (ACl) standard 349.3R-96, Evaluation of Existing Nuclear Safety-Related Concrete Structure. If the detailed visual examination cannot be performed for some reason (e.g., access limitation), CP&L will evaluate the acceptability of the suspect area. This engineering evaluation will assume the suspect area is inaccessible and will address the requirements outlined in 10 CFR 50.55a(b)(2)(ix)(E).
The engineering evaluation will be approved by a Registered Professional Engineer.
In addition, the licensee has stated that the general and/or detailed visual examination will be performed by certified and properly trained personnel. The licensee states, " Personnel performing these visual examinations will be certified in accordance with ANSI /ASME N45.2.6 and a CP&L procedure." Examiners will also be required to successfully complete CP&L approved training on the proper techniques for examining components subject to Subsection IWL. The staff concludes that the proposed alternative provides an acceptable level of quality and safety. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
Relief Reauest No. CIP-15 Code Reauirement:
IWL-2410(a) requires that concrete be examined in accordance with IWL-2510 at 1, 3, and 5 years following the completion of the containment Structural Integrity Test CC-6000 and every 5 years thereafter.
Licensee's Proposed Alternative:
In accordance with 10 CFR 50.55a(a)(3)(i), Carolina Power & Light (CP&L) Company is requesting approval to implement an alternative to the inspection schedule for successive examinations specified in IWL-2410(a). CP&L proposes to schedule the successive five examinations based on the completion date of the baseline examination performed to satisfy the expedited examination requirement outlined in 10 CFR 50.55a(g)(6)(ii)(B)(2).
Staff Evaluation:
The successive 5-year examinations required by IWL-2410(a) are tied to the completion of the StructuralIntegrity Test per Article CC-6000 of Subsection CC, ASME Section lil Code. As stated by the licensee, 'Since the concrete containments at BSEP were constructed prior to establishment of Subsection CC, literal compliance to this code provision cannot be met." As an alternative, the licensee has committed to use the completion date of the baseline examination to establish the specified dates for the 5-year successive examinations. As required by 10 CFR 50.55a(g)(6)(ii)(8)(2), CP&L will perform the baseline examination per Subsection IWL prior to September 9,2001. The staff concludes that the proposed alternative provides an acceptable
. level of quality and safety. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
Relief Reauest No CIP-16
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Code Reauirement-1 Paragraph IWE-2500(c) and Table IWE-2500-1, Examination Category E-C, specify the i
examination requirements for containment surface areas requiring augmented examination per IWE-1242 and IWE-2420. Surface areas accessible from both sides are to be examined using a
,VT-1 examination method. Surface areas accessible from one side only are to be examined for wall thinning using an ultrasonic thickness measurement method in accordance with Section V, T-544. One-foot-square grids are to be used when ultrasonic thickness measurements are performed with the Owner determining the number and location of the grids. The minimum wall thickness of each grid is to be determined using ultrasonic measurements. The location of the minimum wall thickness is to be marked such that periodic reexamination of that location can be performed in accordance with the requirements of Table IWE-2500-1, Examination Category E-C.
Licensee's Proposed Alternative:
The licensee proposed to periorm a visual (VT-1) examination on accessible interior and/or exterior surface areas requiring augmented examination per IWE-1242 and/or IWE-2420. If the surface area is not accessible for visual examination, CP&L has proposed to perform ultrasonic thickness measurements in accordance with the IWE-2500(c).
Staff Evaluation:
Rather than use an ultrasonic thickness measurement, as required by IWE-2500(c), for surface areas requiring augmented examination and accessible from only one side, the licensee has proposed to perform a VT-1 visual examination. As stated by the licensee, "When only the accessible side is subject to conditions that warrant augmented examination per IWE-1240 and/or IWE-2420, CP&L considered the personnel exposure associated with the performance of the ultrasonic thickness measurements unwarranted and a hardship without a compensating increase in quality and safety." If a surface area is subject to augmented examination and not accessible for visual (VT-1) examination, CP&L has committed to perform the ultrasonic wall thickness measurements as required by IWE-2500(c).
In addition, the licensee has proposed to perform a visual (VT-1) examination of only the side of the surface area requiring augmented examination rather than both sides as required by IWE-2500(c)(1). The licensee states, "When only one side is subject to augmented examination per IWE-1240 and/or 2420, CP&L considered the personnel exposure associated with the visual j
examination of the unaffected surface area unwarranted and a hardship without a compensating increase in quality and safety." Instead, the licensee has committed to a visual examination of both sides only when both sides are subject to conditions that warrant augmented examination.
l I
e
. Performing a visual (VT-1) examination in lieu of the ultrasonic thickness measurements on accessible interior and/or exterior surface areas requiring augmented examination per IWE-1240 and/or IWE-2420 will provide an acceptable level of quality and safety. Also, performing a visual (VT-1) examination of only the side of the surface area requiring augmented examination rather than both sides as required by IWE-2500(c)(1) will provide an acceptable level of quality and safety. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
Relief Reauest No. CIP-17 Code Reauirement:
IWA-5240 requires a visual (VT-2) examination of accessible exposed surface.s of pressure-retaining components for evidence ofleakage. For components whose external surfaces are inaccessible for direct VT-2 visual examination, only the examination of the l
surrounding area (including floor areas or equipment surfaces located underneath the components) for evidence of leakage is required.
Licensee's Proposed Afternative:
in accordance with 10 CFR 50.55a(a)(3)(ii), Carolina Power & Li'ght (CP&L) Company is j
requesting approval to implement an alternative to the requirement for performing a visual (VT-2) examination of surface areas that are not accessible during the performance of the I
pneumatic leakage test per 10 CFR 50, Appendix J. As an acceptable alternative, CP&L will perform the required examinations and testing of these affected surfaces in accordance with the applicable requirements specified in the Construction Code, Design Specification, ASME Code,Section XI, and 10 CFR 50, Appendix J. For those affected surface areas that are accessible during the performance of pneumatic leakage test, I
CP&L will comply with the applicable requirements of IWE-5240.
Staff Evaluation:
Since the containments at Brunswick Steam Electric Plant are concrete reinforced, the majority of the exterior surfaces of the metallic liner and penetration sleeves are embedded in concrete and inaccessible for examination. As stated t>y the licensee, "If a repair or replacement activity was performed on the concrete reinforcec: component, the activity would be performed on the interior surface and would be subject to a pneumatic leakage test per Examination Category E-P and 10 CFR Part 50, Appendix J." lWE-5240 would requ!re a visual (VT-2) examination on the external surfaces for evidence of leakage during the performance of the pneumatic leakage test. The licensee considers this requirement impractical for those surfaces not accessible during the performcace of the leakage test. For those surface areas that are accessible during the performance of the pneumatic leakage test, the licensee will comply with the requirements of IWE-5240. The staff considers the requirements of IWE Table 2500-1 (Examination Category E-P) and 10 CFR Part 50, Appendix J to be sufficient to assure the structuralintegrity and leaktightness of the containment surfaces not accessible for examination. Therefore, the alternative proposed by the licensee to perform the examinations and testing of inaccessible surface areas in accordance with the applicable requirements specified in the Construction Code,
1 3 l Design Specification, ASME Code,Section XI, and 10 CFR Part 50, Appendix J, is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
Relief Reauest No. CIP-18 Code Reauirement:
IWA 2430(a) states, "The inspections shall be performed in accordance with the schedule of Inspection Program A of IWA 2431, or optionally, inspection Program B of IWA 2432."
IWA 2430(b) states, "The inspection interval shall be determined by calendar years following placement of the plant into commercial service."
IWA 2432 states, "The inspection intervals shall comply with the following, except as modified by IWA 2430(d):
First inspection Interval-10 years following initial start of plant commercial service Successive /nspection /nterval-10 years following the previous inspection interval "
Licensee's Proposed Alternative:
In accordance with 10 CFR 50.55a(a)(3)(i), Carolina Power & Light (CP&L) Company is requesting approval to implement an alternative to the start date for the First inspection interval specified in IWA-2430(a), IWA-2430(b), and IWA-2432. CP&L proposes to establish May 11,1998, as the date for the start of the First Containment inspection Interval. This date will be used to establish the dates for the three successive Inspection Periods.
Staff Evaluation:
Literal compliance to IWA 2430(a), IWA 2430(b), and IWA-2432 cannot be met since the inspection interval cannot be based on the initial start date of plant commercial service. Instead, CP&L has established the date for the start of the First inspection Interval as May 11,1998, ensuring that the examinations required for the First Inspection Period are completed by l
September 9,2001, as required by 10 CFR 50.55a(g)(6)(ii)(B)(1). The staff concludes that the proposed alternative provides an acceptable level of quality and safety. Therefore, the licensee's proposed alternative is authorized p,ursuant to 10 CFR 50.55a(a)(3)(i).
REFERENCES l
1.
Letter from Keith R. Jury (CP&L) to NRC, " Request to use Alternatives to the ASME Boiler and Pressure Vessel Code,Section XI for Containment inspection," October 28,1998 2.
Letter from Keith R. Jury (CP&L) to NRC, " Request to use Alternatives to the ASME Boiler and Pressure Vessel Code,Section XI for Containment Inspection," May 4,1999 Principal Contributor. C.G. Munson, NRR/DE/EMEB Date: August 10, 1999