ML15198A195

Inservice Inspection Summary Report

ML15198A195
Person / Time
Site:	Braidwood
Issue date:	07/16/2015
From:	Kanavos M Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
BW150073 A1R18
Download: ML15198A195 (11)

Text

Exelon Generation Company, LLC IOn Braidwood Station 35100 South Route Suite 84 Braceville, 60407-9619 www .exeloncorp.com July 16, 2015 BW150073 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Braidwood Station, Unit 1 Facility Operating License No. NPF-72 NRC Docket No. STN 50-456

Subject:

Braidwood Station, Unit 1 lnservice Inspection Summary Report Enclosed please find the post-outage summary report (i.e., 90 day report) for inservice inspection (lSI) examinations conducted during Braidwood Station, Unit 1 Refueling Outage 18 (A 1R18). This report is submitted in accordance with the requirements of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI, "Rules for the lnservice Inspection of Nuclear Power Plant Components," and ASME Code Case N-532-4, "Repair/Replacement Activity Documentation Requirements and lnservice Summary Report Preparation Submission -

Section XI, Division 1." provides the Owner's Activity Report (OAR) for lSI activities conducted during A 1R18 including a list of items with flaws or relevant conditions that required evaluation for continued service and an abstract of repair/replacements activities required for continued service. In addition, provides the results of Containment lSI activities performed in accordance with ASME Section XI, Subsection IWE, "Requirements for Class MC and Metallic Liners of Class CC Components of Light-Water Cooled Power Plants," and Subsection IWL, "Requirements of Class CC Components of Light-Water Cooled Power Plants," with specified modifications and limitations in 10 CFR 50.55a, "Codes and standards."

Please direct any questions you may have regarding this submittal to Mr. Phillip J. Raush, Regulatory Assurance Manager, at (815) 417-2800.

Mark E. Kanavos Site Vice President Braidwood Station Attachments:

1. Owner's Activity Report (OAR) for A 1R18

2. A1 R18 Containment lSI (IWUIWE) Results

ATTACHMENT 1 FORM OAR-1 OWNER'S ACTIVITY REPORT TABLE 1, ITEMS WITH FLAWS OR RELEVANT CONDITIONS THAT REQUIRED EVALUATION FOR CONTINUED SERVICE TABLE 2, ABSTRACT OF REPAIR/REPLACEMENT ACTIVITIES REQUIRED FOR CONTINUED SERVICE

ATTACHMENT 1 FORM OAR-1 OWNER'S ACTIVITY REPORT ReportNumber ~A~1R~1~8~------------------------------------------------------------------------

Piant Braidwood Generating Station, 35100 South Route 53, Suite 84, Braceville, Illinois 60407 Unit No. 1 Commercial Service Date _ _ _.: . :Ju::.:.IYt. . .: : .29::J,:. .:1:. :9:. : 8.: .8_ _ _ Refueling Outage Number _ _.:..;A=.:1Rc..:.:1:.::8:...___

-~(lf:-a-pp-"'ll-ca7bi'"""'e),.---

Current Inspection Interval Third Inspection Interval (lSI), Second Inspection Interval (Containment lSI)

(1", 2"3, 3'3, 4'h, other)

Current Inspection Period Second Inspection Period (ISI and Containment lSI)

(1'1, 2'1d, 3id)

Edition and Addenda of Section XI applicable to the Inspection Plans ASME Section XI 2001 Edition through 2003 Addenda Date 1Revision of Inspection Plans January 26, 2015 I Revision 13 Edition and Addenda of Section XI applicable to repair/replacement activities, if different than the inspection plans Same as above Code Cases used: N-460, N-508-3, N-513-3, N-532-4, N-566-2, N-586-1, N-597-2, N-613-1, N-639, N-649, N-652-1, N-661-1, N-661-2, N-700, N-706-1 N-722-1 N-729-1 N-731 N-751 N-753 CERTIFICATE OF CONFORMANCE I certify that (a) the statements made in this report are correct; (b) the examinations and tests, meet the Inspection Plan as required by the ASME Code,Section XI; and (c) the repair/replacement activities and evaluations supporting the completion of A1R18 (refueling outage number)

CERTIFICATE OF INSERVICE INSPECTION I, the undersigned, holding a valid commission issued by the National Board of Boiler and Pressure Vessel Inspectors and the State or Province of Illinois and employed by HSB Global Standards of ~H~artli;.;::.;:o;.;.rd:::.~,_;C;;.;o:;;..n:..:.;n;.;;;e.;:.;ct:::..;ic;..;;u~t- - - - - - - - - - - - - - -

have inspected the items described in this Owner's Activity Report, and state that to the best of my knowledge and belief, the Owner has performed all activities represented by this report in accordance with the requirements of Section XI By signing this certificate neither the Inspector nor his employer makes any warranty expressed or implied concerning the repair/

replacement activities and evaluation described in this report. Furthermore, neither the Inspector nor his employer shall be liable in any manner for any personal injury or property damage or a loss of any kind arising from or connected with this inspection 4- ~

(Inspector's Signature)

Commissions NB #8756, IL #1085 ANIC National Board, State, Province, and Endorsements Date *1 \ \

~ .

\ Zo \S Page 1 of 5

TABLE 1 ITEMS WITH FLAWS OR RELEVANT INDICATIONS THAT REQUIRED EVALUATION FOR CONTINUED SERVICE Examination Examination Item Description Evaluation Description Category Item Number C-H C7.10 1CS05AB(1CS01SB) Bolting evaluations completed under ATI 1639774-02 and 1697658-02 C-H C7.10 1CV03F Evaluation completed under ATI 1576244-02 D-B 02.10 1FC01P Evaluation completed under ATI 1599672-02 B-P B15.10 1RC8037A body-to-bonnet Bolting evaluation completed under ATI 2476265-02 B-P B15.10 1RC8037C body-to-bonnet Bolting evaluation bound by Evaluation 861305 B-P B15.10 1RC8037B body-to-bonnet Bolting evaluation bound by Evaluation 899596 C-H C7.10 1CV05A Flange Bolted Connections EC 401789 B-P B15.10 1RC8037C body-to-bonnet IR 2486744 EC 401889 B-P B15.10 1RC8037A body-to-bonnet IR 2486752, EC 401889 B-P B15.10 1RC8037D body-to-bonnet IR 2486772, EC 401889 F-A F1.10C 1RY05001V IR 2486784 EC 401898 Page 2 of 5

TABLE 2 ABSTRACT OF REPAIR/REPLACEMENT ACTIVITIES REQUIRED FOR CONTINUED SERVICE Code Item Description Date Repair /Replacement Class Description Of Work Completed Plan Number 2 1CS011B Replace one bolt at a time with 1/29/2014 WO# 1700436-01 new bolt per BACC evaluation (Plan 1-14-002) recommendation._(IR 1598224) 3 1DG01KA-Y1 Retorque existing heat exchanger 2/12/2014 WO# 1704073-01 flange bolting to eliminate (No Plan) leakage at joint. (IR 1605691) 3 1SX046B Replace existing valve which was 3/25/2014 WO# 1596568-01 bound with new valve by welding. (Plan 1-14-001)

(IR 1442884) 3 1DG01KA-X1 Replace existing stationary head 4/14/2014 WO# 1501215-01 with coated spare assembly due (Plan 1-14-004) to epoxy coating damage.

(IR 1646172) 3 1SX25AA Replace segment of pipe with 6/27/2014 WO# 1737992-07 through-wall leak. Leakage (Plan 1-14-015) acceptability originally evaluated in accordance with Code Case N-513-3. (IR 1659136) 3 1FC03009R Repair cracked fillet weld on pipe 7/16/2014 WO# 1748167-01 support. (IR 1671816) (Plan 1-14-016) 3 Spare DG Stationary Head Refurbish spare DG Jacket Water 11/14/2014 WO# 1756460-01 Cooler Stationary Head removed (Plan 1-14-023) under WO 1501215-01 3 1SX057B Replace existing butterfly valve 11/17/2014 WO# 1267929-01 which leaks by seats. (IR 959497) (Plan 1-13-008) 3 1SX052B Replace existing butterfly valve 11/17/2014 WO# 1700484-01 which leaks by seats. (Plan 1-14-046)

(IR 1599312) 3 1DG01KB-X2 Replace jacket water floating end 11/21/2014 WO# 1520645-01 due to damaged Ceramalloy (Plan 1-14-078) coating. (IR 2414320) 3 1DG01KB-Y2 Retorque existing heat exchanger 1/27/2015 WO# 1772837-01 flange bolting to eliminate leakge (No Plan) at joint. (IR 2382478) 2 1CV8119 Replace existing relief valve which 4/6/2015 WO# 1741519-01 was installed without upgraded (Plan 1-14-051) bellows (IR 1659609) 2 1SI04017S Replace existing mechanical 4/7/2015 wo 1698663-39 snubber that passed functional (Plan 1-15-032) testing with marginal results.

(IR 2480143)_

3 1SX27DA Replace segment of pipe with 4/7/2015 WO# 1813976-01 through-wall leak. Leakage (Plan 1-15-009) acceptability originally evaluated in accordance with Code Case N-513-3. (IR 2468066)

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TABLE 2 ABSTRACT OF REPAIR/REPLACEMENT ACTIVITIES REQUIRED FOR CONTINUED SERVICE Code Item Description Date Repair /Replacement Class Description Of Work Completed Plan Number 3 1CC9495A Replace existing check valve 4/8/2015 WO# 1670802-01 cover due to galled threads (Plan 1-15-061) observed during PM surveillance.

2 1SD23093S Replace existing mechanical 4/8/2015 WO# 1698663-30 snubber that failed to (Plan 1-15-017) meet the visual examination acceptance criteria. (IR 2479809) 2 1SD24073S Replace existing mechanical 4/8/2015 WO# 1698663-31 snubber that failed to (Plan 1-15-021) meet the functional test acceptance criteria 2 151010355 Replace existing mechanical 4/8/2015 WO# 1698663-35 snubber that passed functional (Plan 1-15-018) test but upon disassembly was found to have internal corrosion from water intrusion.

(IR 2480142) 2 1SI24012S Replace existing mechanical 4/8/2015 WO# 1698663-41 snubber that passed functional (Plan 1-15-020) testing but upon disassembly was found to have a cracked screw shaft. (IR 2480085) 3 1VP01AC Existing bolting replaced, no 4/9/2015 WO# 1520768-02 documented discrepancy. (Plan 1-13-030) 2 1CV8346 Replace existing valve disc to 4/9/2015 WO# 1566349-01 correct seat leakage. (Plan 1-13-016)

(IR 1376583) 2 1CV8117 Replace relief valve due to as 4/9/2015 WO# 1670751-01 found set point testing. (Plan 1-14-038)

(IR 2482746) 1 1RC01BB-A Replace control valve on hydraulic 4/9/2015 WO# 1821370-01 snubber due to failed functional (Plan 1-15-016) test. (IR 2479629) 1 1RC01R Reduce liquid penetrant indication 4/10/2015 WO# 1689688-23 in embedded flaw repair of RPV (Plan 1-15-019)

Head Penetration 69.

(IR 2479588) 1 1RC8040C Replace existing valve bonnet and 4/11/2015 WO# 914344-01 yoke to repair valve bonnet leak. (Plan 1-06-039)

(IR 2481454) 2 1CV131 Replace valve trim kit as part of 4/11/2015 WO# 1683271-01 valve rebuild to address previous (Plan 1-14-033) issues with valve sticking.

(IR 1570063) 2 1SI06031R Modify existing support to correct 4/11/2015 WO# 1700484-01 design issues associated with (Plan 1-14-049)

NCIG-05 misapplication.

(IR 1383554) 3 1AF006A Replace existing valve disc to 4/11/2015 WO# 1754474-01 correct seat leakage. (Plan 1-15-010)

(IR 1275290)

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TABLE 2 ABSTRACT OF REPAIR/REPLACEMENT ACTIVITIES REQUIRED FOR CONTINUED SERVICE Code Item Description Date RepairI Replacement Class Description Of Work Completed Plan Number 3 15X27DB Perform flaw disposition per Code 4/11/2015 WO# 1822647-01 Case N-513-3 and local weld build (Plan 1-15-023) up repair at degraded area of pipe in accordance with Code Case N-661-1/N-661-2.

(IR 2482749) 3 1AF02A Existing flange bolting replaced, 4/11/2015 WO# 1670764-01 no documented discrepancy. (Plan 1-14-040) 2 1CV121 Replace valve trim kit as part of 4/12/2015 WO# 1520505-01 upgrade per EC 385832. (Plan 1-13-022) 2 1500548 Replace existing valve bonnet as 4/13/2015 WO# 1631254-01 part of valve restoration for leak (Plan 1-14-013) seal injection clamp removal.

(IR 1498331) 2 15!007 Repair Weld FW-1 that failed 4/14/2015 WO# 1692235-29 radiography. (IR 2469339) (Plan 1-14-066) 2 1AF03ED Repair Weld FW-3 to orientate 4/13/2015 WO# 1722810-01 flan_ge. (IR 2472917} (Plan 1-14-055) 3 05X63A Replace existing carbon steel 5/15/2015 WO# 859747-01 valve with stainless steel valve (Plan 1-13-067)

(EC 357816) to address packing leak that was impacting sump inputs. (IR 2468744) 3 1DG01KB-Y1 Retorque existing heat exchanger 5/19/2015 WO# 1792640-01 flange bolting. (IR 2415889) (No Plan) 3 15X03A Replace weld neck flange due to 5/20/2015 WO# 1831958-05 through-wall leak. (IR 2501820) (Plan 1-15-030) 2 1CS020A Replace flange bolting per BACC 6/8/2015 WO# 1747286-01 Program evaluation (Plan 1-15-029) recommendation. (IR 2488870)

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ATTACHMENT 2 A 1 R18 CONTAINMENT lSI (IWE/IWL) RESULTS

ATIACHMENT2 A1R18 CONTAINMENT lSI (IWEJIWL) RESULTS REPORT OF CONTAINMENT DEGRADATION Containment inspections were performed in accordance with Subsection IWE (Requirements for Class MC and Metallic Liners of Class CC Components of Light-Water Cooled Power Plants) and IWL (Requirements for Class CC Components of Light-Water Cooled Power Plants) of ASME Section XI, Division 1, (2001 Edition through the 2003 Addenda) along with specified modifications and limitations in 10CFR 50.55a. The scope of the examinations during A 1R18 included locations below the moisture barrier (MB) where previous examinations revealed loss in excess of 1/64" but not exceeding 4/64".

(ASME IWE) REPORT OF CONTAINMENT DEGRADATION Augmented Section XI IWE examinations of the Class CC liner examinations during A 1R18 (Second Period of the Third Interval Containment lSI) were performed in accordance with the requirements of ASME Section XI, Table IWE-2500-1, "Category E-C, Containment Surfaces Requiring Augmented Examination". The scope of the examinations included locations below the moisture barrier where previous examinations revealed loss in excess of 1/64" but did not exceed 4/64".

Exelon Procedures ER-AA-330-007, "Visual Examination of ASME Section XI Class MC Surfaces and Class CC Liners*: ER-AA-335-018 "Visual Examination of ASME /WE Class MC and Metallic Liners of CC Components", and ER-AA-335-004 "Ultrasonic Measurement of Material Thickness and Interfering Conditions" were used to perform the examinations.

A description of the type and estimated extent of the conditions that led to the degradation [1 OCFR 50.55a(b)(2)(ix)(A)(2)(i)]:

During the performance of A 1 R18 augmented exams, no additional degradation was found at the locations below the moisture barrier. None of the liner metal losses exceeded 4/64",

therefore no weld repairs were required. With regard to the existing degradation examined during A 1 R18, the most notable type of degradation was liner metal loss due to corroded metal just below the MB, found as a result of UT of augmented areas resulting in metal loss of varying depths. The maximum pit depth identified was 0.021" (approximately 1/64"). It should be noted this metal loss took place prior to application of Keeler and Long 9600 Series coating in A 1R14. All UT areas were found coated and dry.

Extent of Condition:

The maximum metal loss of 0.021" (approximately 1/64") occurred at one location based on UT examinations of the areas inspected. These examinations also indicated that the liner plate had contained numerous pits in the areas below the MB. It should be noted that areas examined in A 1R 18 were previously identified in A 1R 14 or A 1R 15 and not repaired inA1R17.

The depths of the pits did not change from exams performed in previous period (A 1R14 or A 1R15); therefore these areas no longer require augmented examinations in accordance with IWE-2420{c).

Page 1 of 3

ATTACHMENT 2 A 1 R18 CONTAINMENT lSI (IWE/IWL) RESULTS Description of the Conditions That Led to the Degradation:

Based on the recorded observations it is evident that the significant portions of the liner plate degradation below the moisture barrier (MB) are attributed to corrosion. The liner plate surface below the MB was coated with Carbo Zinc CZ11 in year 2000. Carbo Zinc CZ11 does not tolerate improper surface preparation and is not recommended for use unless white metal condition with a contoured surface profile is achieved. Since this strip of liner plate below the MB is not easily accessible, it is unlikely that the proper surface preparation was attained during the initial application. Furthermore, the liner plate surface may not have been completely dried (some moisture left in the wall from the wet Cerafibre resting against it) when the MB was replaced in 2000. In the year 2000, the Cerefibre was found wet and adhering to the metal liner. The liner most likely experienced a slow chronic corrosion rate prior to 2000. The bulk of the liner corrosion likely occurred soon after the year 2000 when the liner below the moisture barrier was coated with Carbo Zinc CZ11.

Keeler and Long 9600 Series coating has been applied as the new Service Level I coating in A 1R 14 through A 1R18. Keeler and Long 9600 Series was chosen for the coating in containment because it does not require white metal surface conditions prior to coating.

Evaluation of each area, and the result of the evaluation

[1 OCFR 50.55a(b)(2)(ix)(A){2)(ii)]:

Engineering evaluation EC #402443 was performed to address all the indications. The evaluation determined that the liner plate with the highest degraded condition 0.021" loss (approximately 1/64") will remain operational and meet its intended design function throughout the upcoming cycle. Additional augmented examinations are scheduled during the next refuel outage (A 1R19). As previously discussed, weld repairs were not required at any of the locations since the liner material losses did not exceed 4/64".

Description of Necessary Corrective Actions Completed

[1 OCFR 50.55a{b)(2){ix){A)(2)(iii)]:

1) Approximately 66' of liner plate directly below the MB that was examined previously in either A 1R14 or A 1R15 were re-examined by VT-1 visual examination after the MB was removed.

2) Select areas previously classified as augmented inspection locations (> 1/64" metal loss) in A 1R14 or A 1R15 and not repaired in A 1R17 were examined using the Ultrasonic examination method to document actual liner plate thicknesses in the vicinity of these pitted areas.

3) Engineering evaluation EC #402443 was completed to provide justification for the acceptability of the liner plate at its thinnest location and continued operation of Unit 1 without additional repair or replacement activities on the containment liner plate until the next time it is required to be reexamined during the Third CIS I Period.

4) The liner surfaces at all the exposed locations where the moisture barrier had been removed were coated with for Keeler and Long 9600 series coating (used for Levell coating in containment) during A 1R18 along with new Cerafibre and new MB.

5) A new MB was installed at all areas where the existing MB was removed during A 1R18. A post installation GV exam of the entire replacement MB was performed.

No cracks or voids which would allow water intrusion were observed.

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ATTACHMENT 2 A1 R18 CONTAINMENT lSI (IWEIIWL) RESULTS

6) Portions of Class CC liner below the MB have been categorized as Category E-C (Containment Surfaces Requiring Augmented Examination) in the Unit 1 lSI schedule.

Proposed Corrective Actions for the Third CISI Period (A1R19 or A1R20):

Schedule VT-1 and UT examinations of all containment liner plate directly below the MB that exhibited metal thickness losses greater than 1/64" in A 1R 16 that were not repaired in A1R17 (ATI #1363165-04), and any new augmented areas found as a result of UTs during A 1R17 or were repaired and still remain augmented (AT I #15707 41-01 ).

Conclusions/Findings:

The liner plate is acceptable and capable of performing its intended design function until A1R19 where additional augmented examinations are scheduled. (ATI #1363165-04)

(ASME IWL) REPORT OF CONTAINMENT DEGRADATION No evidence of degradation was identified for ASME Class CC Components during this cycle.

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