RNP-RA/08-0018, Request for Relief from ASME Boiler and Pressure Vessel Code, Section XI, Subsections IWE and Iwl Requirements for Containment Inspections

From kanterella
Jump to navigation Jump to search

Request for Relief from ASME Boiler and Pressure Vessel Code,Section XI, Subsections IWE and Iwl Requirements for Containment Inspections
ML081010435
Person / Time
Site: Robinson Duke Energy icon.png
Issue date: 04/04/2008
From: Baucom C
Progress Energy Carolinas
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
RNP-RA/08-0018
Download: ML081010435 (15)


Text

10 CFR 50.55a Progress Energy, Serial: RNP-RA/08-0018 APR 04 2008 United States Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike.

Rockville, Maryland 20852 H.'B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 DOCKET NO. 50-261/LICENSE NO. DPR-23 REQUEST FOR RELIEF FROM ASME BOILER AND PRESSURE VESSEL CODE, SECTION XI, SUBSECTIONS IWE AND IWL REQUIREMENTS FOR CONTAINMENT INSPECTIONS Ladies and Gentlemen:

The purpose of this letter is for Carolina Power and Light Company, also known as Progress Energy Carolinas, Inc., to request relief, in accordance with 10 CFR 50.55a(a)(3), from certain requirements of Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code,Section XI, involving containment inspection examinations at the H. B. Robinson Steam Electric Plant, Unit No. 2.

Attachment I provides a summarized listing of these proposed relief requests. Attachment II provides the actual proposed relief requests, IWE/IWL-RR-01 through IWE/IWL-RR-03, and each includes the applicable ASME B&PV Code requirement, a description of the relief requested, a justification for the requested relief, the proposed alternative examination, and the planned implementation schedule.

If you have any questions concerning this matter, please contact Mr. C. A. Castell at (843) 857-1626.

Sincerely, Charles T. Baucom Manager - Support Services - Nuclear CTB/ahv Progress Energy Carolinas, Inc.

Robinson Nuclear Plant 3581 West Entrance Road Hartsville, SC29550 kA Z

United States Nuclear Regulatory Commission Serial: RNP-RA/08-0018 Page 2 of 2 Attachments:

I. List of Relief Requests II. Relief Requests c: Mr. V. M. McCree, NRC, Region II Ms. M. G. Vaaler, NRC, NRR NRC Resident Inspector

United States Nuclear Regulatory Commission Attachment I to Serial: RNP-RA/08-0018 Page 1 of 1 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 REQUEST FOR RELIEF FROM ASME BOILER AND PRESSURE VESSEL CODE, SECTION XI, SUBSECTIONS IWE AND IWL REQUIREMENTS FOR CONTAINMENT INSPECTIONS LIST OF RELIEF REOUESTS Request Number Applicable Code Title Section(s)

IWE/IWL-RR-01 Table IWE-2500-1, Visual Examination of Insulated Containment Liner Examination Category E-A IWE/IWL-RR-02 Table IWE-2500-1, Visual Examination of Moisture Barriers Examination Category E-A IWE/IWL-RR-03 IWE-2420(b) and (c) Successive Examinations Following a Repair

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page I of 12 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 REQUEST FOR RELIEF FROM ASME BOILER AND PRESSURE VESSEL CODE, SECTION XI, SUBSECTIONS IWE AND IWL REOUIREMENTS FOR CONTAINMENT INSPECTIONS RELIEF REQUESTS

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page 2 of 12 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 RELIEF REQUEST NO. IWE/IWL-RR-01 VISUAL EXAMINATION OF INSULATED CONTAINMENT LINER Code Requirements for Which Relief is Requested The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV)

Code, 2001 Edition, 2003 Addenda,Section XI, Table IWE-2500-1, "Examination Categories,"

Examination Category E-A, Item Number El. 11, requires a general visual examination of 100%

of the accessible surface areas of containment in accordance with acceptance standard IWE-35 10, "Standards for Examination Category E-A, Containment Surfaces," paragraph IWE-3510.2, "Visual Examination of Coated and Noncoated Areas," for Class MC and metallic liners of Class CC components.

This relief was previously approved for the First Ten-Year IWE/IWL Inspection Interval under a Safety Evaluation Report (TAC No. MA4637) dated July 26, 1999.

Specific Relief Requested Relief is requested from performing general visual examinations in accordance with ASME B&PV Code, 2001 Edition, 2003 Addenda,Section XI, Table IWE-2500-1, Examination Category E-A, on the accessible surface areas of the containment liner which are insulated. It is proposed to perform a general visual examination on those portions of the insulated containment liner that are exposed when a maintenance activity requires removal of the liner insulation.

This request for relief is applicable to the insulated portion of the containment liner classified as Class MC and subject to the requirements of Table IWE-2500-1, Examination Category E-A, at the H. B. Robinson Steam Electric Plant (HBRSEP), Unit No. 2 (Figure 1).

Alternative Examination(s)

The alternative examination proposed is to perform a general visual examination on those portions of the insulated containment liner that are exposed when a maintenance activity requires removal of the liner insulation. This examination will be completed if not previously performed in the inspection interval.

Basis for Requesting Relief In accordance with 10 CFR 50.55a(a)(3)(i), relief is requested for HBRSEP, Unit No. 2, on the basis that the proposed alternative, in conjunction with the examinations that have occurred during Refueling Outage (RO)-1 8, RO-19, RO-20, RO-22, RO-23, and RO-24 provide an acceptable level of quality and safety.

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page 3 of 12 Justification for Grantin2 Relief Relief is requested from the Code requirements for general visual examinations of the containment liner in areas that are insulated. Alternative examinations stated below provide an acceptable level of quality and safety.

The containment liner at HBRSEP, Unit No. 2, is covered by insulation and stainless steel sheathing. The insulation and stainless steel sheathing form part of the defense-in-depth philosophy of the containment liner at HBRSEP, Unit No. 2. The three barriers that protect the containment liner pressure boundary are as follows:

1. Insulation and sheathing
2. Coating
3. Containment liner thickness The removal and reinstallation of the insulation sheathing panels has been determined to be time consuming and results in hardship and unusual difficulty.

During previous inspections, panels have been removed for maintenance purposes and the containment vessel liner examined and determined to meet requirements.

The following table provides a history of IWE and IWL examinations:

Outage Examinations Performed RO-18 (1998) Portions of the containment vessel liner behind the insulation.

RO-19 (1999) Portions of the containment vessel liner behind the insulation, electrical penetrations, airlock, and portions of the reinforced concrete exterior.

RO-20 (2001) Portions of the containment vessel liner behind the insulation, the dome interior, mechanical penetrations, equipment hatch, and the remaining portions of the reinforced concrete exterior, including the dome exterior.

RO-22 (2004) Additional panels were removed from the bottom row to allow examination of the containment vessel liner behind the insulation.

RO-23 (2005) Portions of the containment vessel liner behind the insulation of the equipment hatch and several insulation panels at the 348-foot elevation.

RO-24 (2007) Portions of the containment vessel liner behind the insulation, the dome interior,, mechanical penetrations, equipment hatch, and the remaining portions of the reinforced concrete exterior, including the dome exterior.

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page 4 of 12 The proposed alternative examination provides an acceptable level of quality and safety without presenting an undue challenge to the insulation panels.

Implementation Schedule This relief will be implemented during the HBRSEP, Unit No. 2, Second Ten-Year IWE/IWL Inspection Interval for containment inspections required by ASME B&PV Code, 2001 Edition, 2003 Addenda,Section XI, Subsections IWE and IWL.

United.States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page 5 of 12 FIGURE 1 W.ALL D09ELINERPLITE ANAD 15 0 A03E E -3S1-IV ADEMEL 32'-f FOR COhUR&ATION TTrrINMEN7T S IEE 8.19 EL35r-W ... .- SPRINGLINE0. 352-V LEGEND INACCESSIBLE FOR VISUAL INSPECTION IWE BOUNDARY 151'-f" I.D. FOR INFORMATION

$ COMPONENT IDENTIFIER 151

1) TEST CHANNELS AREINSTALLED OVERALL LINER SEAM WELDS.
2) W4 INSULATION AND26 GAUGE SHEATHING IS INSTALLED OVER LINERFROM ELEV. 228'-0' TO 367'-10,

REFERENCES:

1) G-1903.34 II
2) G-i9O343
3) 0-i90353

ýFORDETAL SE FIuRE 5 (HT. 97)4) G-590359 EL253*-e NERPLATE-LI~ j LWSA EL . n E b26AL 181

2)
  • REV DATE SEACRINTIS INTA ED PVERD

,-'FOR~~~~~~~~IGR SH' 9)4 2) C--BB

-**5 9-- 14ALSEFGR LINER FPEAT, L ENGINEERT 367_-1__,

HB2!0 1 I-E- aAL1.. 19P5, 1.

SAFETY RELATED LlPROGIRESS ENERGY Progress ENGINEERING SECTION 'Energ pILA-4r RDHINSON PLANT- UNIT2 IscALE.NONE TTE EXAMINATIONI BOUNDARY OF CONTAINMENT LINER (MJAT ANDCYLINDER) 1041.

FIlE; FILE: Orm Nin. i..

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page 6 of 12 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 RELIEF REQUEST NO. IWE/IWL-RR-02 VISUAL EXAMINATION OF MOISTURE BARRIERS Code Requirements for Which Relief is Requested The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV)

Code, 2001 Edition, 2003 Addenda,Section XI, Table lWE-2500-1, "Examination Categories,"

Examination Category E-A, Item Number E 1.30, requires a visual examination of the containment moisture barrier, in accordance with Figure IWE-2500-1, "Examination Areas for Moisture Barriers," for Class MC, and metallic liners of Class CC, components.

The required method is a general visual examination of 100% of the moisture barrier materials intended to prevent intrusion of moisture against inaccessible areas of the pressure-retaining metal containment shell or liner at concrete-to-metal interfaces and at metal-to-metal interfaces which are not seal-welded. Containment moisture barrier materials include caulking, flashing, and other sealants used for this application. Deferral of the test to the end of the interval is not applicable due to the 100% per period requirement.

This relief was previously approved for the First Ten-Year IWE/lWL Inspection Interval under a Safety Evaluation Report (TAC No. MA4637) dated July 26, 1999.

Specific Relief Requested Relief is requested from performing general visual examinations, in accordance with ASME B&PV Code, 2001 Edition, 2003 Addenda,Section XI, Table IWE-2500-1, Examination Category E-A, on the containment moisture barriers. In lieu of this requirement, it is proposed that a general visual examination of the containment moisture barrier be performed when maintenance activities require removal of the liner insulation which exposes the moisture barrier.

This request for relief is applicable to components classified as Class MC and subject to the requirements of Table IWE-2500-1, Examination Category E-A, at the H. B. Robinson Steam Electric Plant (HBRSEP), Unit No. 2.

Alternative Examination(s)

The alternative examination to the 100% per period general visual examination of containment moisture barriers is to perform a general visual examination on those portions of the 228-foot elevation concrete-to-metal liner moisture barrier that are exposed when a maintenance activity requires removal of the associated barrier insulation.

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page 7 of 12 Basis for Requesting Relief In accordance with 10 CFR 50.55a(a)(3)(i), relief is requested for HBRSEP, Unit No. 2, on the basis that the proposed alternative provides an acceptable level of quality and safety.

As shown in Figure IWE-2500-1, and noted in Table IWE-2500-1, moisture barrier materials are intended to prevent intrusion of moisture against inaccessible areas of the pressure-retaining metal containment shell or liner at concrete-to-metal interfaces and at metal-to-metal interfaces which are not seal-welded. For HBRSEP, Unit No. 2, the moisture barrier that meets this definition is the epoxy joint filler that interfaces with the concrete-to-containment liner interface at the 228-foot elevation. Figures 1 and 2 provide details of that interface. This moisture barrier is covered with insulation that provides an additional moisture barrier. The specification for the insulation requires: the exposed surface be impervious to. water; suitable water seals at points where the insulation ends are exposed to containment atmosphere; and, sealant use to prevent water leakage to the containment liner. The combination of the epoxy joint filler moisture barrier and the impervious insulation, in conjunction with the examinations that have occurred during Refueling Outage (RO)-l 8, RO-19, RO-20, and RO-22, provide an acceptable level of quality and safety.

Justification for Granting Relief The containment internal moisture barrier is covered with an additional layer of insulation and stainless steel sheathing. The specification for the additional layer of insulation and stainless steel sheathing requires that the exposed surface be impervious to water, provide suitable water seals at points where the insulation ends are exposed to containment atmosphere, and sealant use to prevent water leakage to the containment liner.

During RO-18, several insulation panels at the 228-foot elevation were removed and the moisture barrier at the 228-foot elevation was visible. The moisture barrier was removed to' allow inspection of the containment liner adjacent to the moisture barrier. The containment liner adjacent to the moisture barrier did not show evidence of corrosion, indicating that the moisture barrier was performing its function.

Based on the inspection in RO- 18, a decision was made to remove the sheathing panels on the lowest row to inspect for corrosion. A small number of these panels were not able to be removed because of obstructions or high radiation areas. During RO- 19, VT-3 examinations were performed revealing degraded portions of the moisture barrier. These degraded portions were removed and replaced as well as portions that were not degraded. Inspection of the moisture barrier was completed in RO-20, with portions of the moisture barrier replaced and restored to design condition. In addition, in RO-22 portions of the moisture barrier were replaced and restored to design conditions.

In addition, during the First Ten-Year Inspection Interval, insulation panels at the 228-foot elevation were removed and the moisture barrier at the 228-foot elevation was examined and determined to be acceptable.

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page 8 of 12 The proposed examination provides an acceptable level of quality and safety while not presenting an undue challenge to the moisture barrier insulation panels.

Implementation Schedule This relief will be implemented during the HBRSEP, Unit No. 2, Second Ten-Year IWE/IWL Inspection Interval for containment inspections required by ASME B&PV Code, 2001 Edition, 2003 Addenda,Section XI, Subsections IWE and IWL.

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page 9 of 12 FIGURE 1 WALL ANDDONELINERPlaTE I S IeV '-'or-ti FORCONTI,*ATION ABOVE E EL 352'-8 SEEArrTcHMENT

.19 U. 5-- , .... .,SPRI LINEa. 352-4t LEGEND INACCESSIBLE FOR VISUAL INSPECTION IWE BOUNDARY

___ I.O.FOR _-_ _ INFORMATION I( [ISI COMPONENT IDENTIFIER NOES

1) TEST CHANNELS ARE INSTALLED OVER ALL LINER SEAM \VEUWS,
2) 04' INSULATION AND 26 GAUGE SHEATHING IS INSTALLED OVER LINER FROM ELEV. 228'-Z" TO 367'-1V.

REFERENCES:

1) G-190334
2) G-190343
3) 0-19g258 ETAIL F SEE FIGUREN5 SlT.t9 7) 4) G-190359 aL 2531-t 1 E7F FAE LINEPLATE-6 N t, RE DATE DERIPrIDN DON C' WPPRO
  • . c* cm - W,
  • LIN ERPLA T E SS~t' ENG INEER:-

LEVL- SAFETY 1CONIY RELATED PROGRESS E~M~ 10 N PogesS EDGINEER[NG SECTION Erigy pLmI:ROBINSONPLANT- UNIT2 Isc..t NONE TIT., EXAMINATION BOUNDARYOF CONTAINMENT LINER (MATANDCYLINDER)

FIGURE14 HHNR2-12618 1. 0 19iN 1q41.

FILE: VPAw - i -

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-001 8 Page 10 of 12 FIGURE 2 GROUTED TENDON (HIGH STRENGTHSTEELBARS INSIDE 6* DIAMETER PIPE)

LEGEND 00 INACCESSIDLE FOR A I -28 VISUAL INSPECTION o' IWE BOUNDARY o -t13 INSULATION FROMEL 228'-B" TO EL 36T7-IZ FOR INFORMATION

, THREADED STUDANDNUT(TYPICAL)

SrISI COMPONENT IDENTIFIER CONTAINMENT CONCRETE %VALL 0 CONTAINMENT LINER

. 0. (NOTE1)I NOTES:

C... [ /1) THE.CONTAINMENT LINER IS %r THICKFROMEL. 226-0' TO EL 2.53-2'.

4" X -4 MOISTURE . BARRIER THICK FROMEL 253-E" TO 352--B" ANDIf THICKABOVE352-0".

o IN CONCRETE NOTCH

REFERENCES:

CAULKING 1) G-190343 0 "2) G-190353 0 ,, 3) G-190358

.4 , b. , EL 228'-" -4) 0-1g23.s A " FLOORSLAB 5) RELIEF REQUEST,WE/DVL-O2 FIGURE I EL-226-*"- "V "'4 TOP OF MATLINER BASE MAT . 7 A 1f TO 4"4LINER TRANSITION f C E595r P jREDATt~E DESCRIPTION DOW JOK AR'flr PROFE*SSIONAL.

ENMNEER; GUALITY LV' SAFETY RELATED PROGESS DiERGY lo ogress ENGINEERING SECTION Ener RANT:ROBINSONPLANT- UNIT2 I, HIRE TIM EXAMINATION BOUNDARY OF CONTAINMENTLINER (DETAIL ATMOISTURE BRRITI*R)

FIGURE16 LBR2-16H1 197 RILEM HQ 9T

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page 11 of 12 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 RELIEF REQUEST NO. IWE/IWL-RR-03 SUCCESSIVE EXAMINATIONS FOLLOWING A REPAIR Code Requirements for Which Relief is Requested The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV)

Code, 2001 Edition, 2003 Addenda,Section XI, Paragraph IWE-2420, "Successive Inspections,"

Items (b) and (c), provide requirements for successive examinations of Class MC and metallic liners of Class CC components when examination results require evaluation of flaws or areas of degradation in accordance with IWE 3000, "Acceptance Standards," and the component is found to be acceptable for continued service.

IWE-2420(b) states, "When examination results require evaluation of flaws or areas of degradation in accordance with IWE 3000, and the component is acceptable for continued service, the areas containing such flaws or areas of degradation shall be reexamined during the next inspection period listed in the schedule of the inspection program of IWE-24 11 or IWE-2412, in accordance with Table IWE-2500-1, Examination Category E-C." IWE-2420(c) states, "When the reexaminations required by IWE-2420(b) reveal that the flaws or areas of degradation remain essentially unchanged for the next inspection period, these areas no longer reqiuire augmented examination in accordance with Table IWE-2500-1, Examination Category E-C."

This relief was previously approved for the First Ten-Year IWE/IWL Inspection Interval under a Safety Evaluation Report (TAC No. MA4637) dated July 26, 1999.

Specific Relief Requested Relief is requested from the provisions of Paragraphs IWE-2420(b) and (c) that require successive examinations of repaired areas in accordance with Table IWE-2500-1, Examination Category E-C. In lieu of the successive examinations required by IWE-2420, an acceptable level of quality and safety will be provided by the repair process and subsequent acceptance examinations and evaluations.

Alternative Examination(s)

Alternative examinations are those inspections and evaluations required by the ASME Code for repairs, as discussed below.

United States Nuclear Regulatory Commission Attachment II to Serial: RNP-RA/08-0018 Page 12 of 12 Basis for Requesting Relief In accordance with 10 CFR 50.55a(a)(3)(i), relief is requested for the H. B. Robinson Steam Electric Plant (HBRSEP), Unit No. 2, on the basis that the proposed alternative provides an acceptable level of quality and safety.

The purpose of the repair is to restore the component to an acceptable condition for continued service and to prevent recurrence. Following the repair, examination is performed in accordance with Paragraph IWA-2200, "Examination Methods." Acceptance of this examination will confirm the absence of the unacceptable condition or reveal that the condition no longer exceeds the established acceptance standards. In both cases, this examination verifies that the repair has restored the component to an acceptable condition, and can be returned to service. Additionally, following a repair, Appendix J testing may be required in accordance with Paragraph IWE-5220, "Tests Following Repair/Replacement Activities." Once the repair has been verified as acceptable, successive examinations of the repaired area, in accordance with Examination Category E-C of Table IWE-2500-1, "Examination Categories," are not warranted.

Justification for Granting Relief As discussed above, following the repair, examination is performed in accordance with Paragraph 1WA-2200, "Examination Methods." Acceptance of this examination will confirm the absence of the unacceptable condition or reveal that the condition no longer exceeds the established acceptance standards. Thus, the proposed alternative provides an acceptable level of quality and safety.

Implementation Schedule This relief will be implemented during the HBRSEP, Unit No. 2, Second Ten-Year IWE/IWL Inspection Interval for containment inspections required by ASME B&PV Code, 2001 Edition, 2003 Addenda,Section XI, Subsections IWE and IWL.