SBK-L-17117, Inservice Inspection Examination Report

Inservice Inspection Examination Report

ML17200A109
Person / Time
Site:	Seabrook
Issue date:	07/18/2017
From:	Browne K NextEra Energy Seabrook
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
SBK-L-17117
Download: ML17200A109 (7)

Text

NEXTera ENERGY e SEABROOK July 18, 2017 Docket No. 50-443 SBK-L-17117 United States Nuclear Regulatory Commission Attn.: Document Control Desk Washington, D.C. 20555-0001 Seabrook Station Inservice Inspection Examination Report Enclosed is the NextEra Energy Seabrook, LLC Inservice Inspection Examination Report for inspections conducted prior to and during the eighteenth refueling outage that concluded on May 1, 2017. The enclosed report is submitted pursuant to the requirements of paragraph IWA-6240 of the 2004 Edition of Section XI of the American Society of Mechanical Engineers (ASME)

Boiler and Pressure Vessel Code and approved ASME Code Case N-532-4. Additionally, a copy of this letter and the enclosed report are being submitted to the State of New Hampshire.

Should you have any questions regarding this information, please contact Mr. James Crowley, Engineering Support Manager, at (603) 773-7470.

Sincerely, Licensing Manager NextEra Energy Seabrook, LLC, P.O. Box 300, Lafayette Road, Seabrook, NH 03874

United States Nuclear Regulatory Commission SBK-L-17117/Page 2 cc: NRC Region I Administrator NRC Project Manager, Project Directorate I-2 NRC Senior Resident Inspector Wayne Brigham, Boiler Inspector New Hampshire Department of Labor Inspection Division PO Box 2076 Concord, NH 03302-2076

Enclosure to SBK-L-17117 Page 1 of4 FORM OAR-1 OWNER'S ACTIVITY REPORT Report Number: ISl-SBK-2017 Plant: NextEra Energy Seabrook, LLC P.O. Box 300 Seabrook, NH 03874 Commercial Service Date: August 19, 1990 Refueling Outage No.: OR18 Current Inspection Interval: ISi-Third Interval and IWE Second Interval Current Inspection Period: ISi Third Interval Second Period and IWE/IWL Second Interval Second Period Edition and Addenda of Section XI applicable to the inspection plans:*

ISi Third lnterval-2004 Edition No Addenda and IWE/IWL Second lnterval-2004 Edition No Addenda Date and Revision of inspection plans: ISi Third Interval and IWE/IWL Second Interval Effective -

December 28, 2016 Rev. 17 Edition and Addenda of Section XI applicable to repairs and replacements, if different than the inspection plan: ASME Section XI 2004 Edition no Addenda Code Cases Used: Approved Code Cases listed in Inspection Plan 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 OR18 conform to the requirements of Section XI.

Signed _ _ _ _ __ _._- -~-=-

• Owner or Owners Designee, Title

• ~ ______ Date -~?.....,...0_...~_,_0___Y___7_

7 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 New Hampshire and employed by The Hartford Steam Boiler Inspection and Insurance Company of Hartford, CT 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. F.urt ore, neither the inspector nor his employer shall be liable in any manner for any per: o I inj y or property damage or loss of any kind arising from or connected with this insp i n.

/ Commissions f.LB l()7 tS- B,X

:, N., R. i N.li 7(;,{)

National Board, State, Province and Endorsements Date 7- l!J-'9c {2

Page 2 of 4 FORM OAR-1 OWNER'S ACTIVITY REPORT TABLE 1 ITEMS WITH FLAWS OR RELEVANT CONDITIONS THAT REQUIRED EVALUATION FOR CONTINUED SERVICE Examination Item Category and Evaluation Description Description Item Number E-A Degradation of For OR18, of the 21 Leak Chase Test Connections (LCTC)

E1.30 Moisture Barrier examined, evidence of degradation was identified in 11 LCTCs.

Two LCTCs were found with pressurized water, five with water present when viewed by a boroscope, and four were moist when viewed by a boroscope.

Chemistry was able to sample two of the seven LCTCs with water that had been noted by the boroscope examination. The boroscope cable is very small and able to navigate and extend through the tubing bends where the chemistry tubing used to draw a sample could not travel as far to obtain a sample.

Chemistry ran a comparable analysis on these two OR18 samples as was done in OR17. Both OR18 samples have a pH of 13.

There is no indication with these results that groundwater is leaking into the liner area. The gamma results are also consistent with OR 17 results and that these LCTC water samples are not indicative of active leaks. Overall the locations examined by boroscope appear to be in good condition with no significant level of corrosion/metal loss identified.

Based on the information and data obtained, it is evident that the inaccessible portions of the liner plate have maintained their specified design function as a leak-tight membrane.

Although a qualified NOE method could not be performed on the liner plate in locations associated with degraded moisture barriers, the body of information included in this evaluation supports the conclusion that the inaccessible portions of the liner plate have not experienced any appreciable loss of material that would compromise the liner plate's ability to perform its specified design function.

The following summarizes the information collected that support the conclusion that the liner plate has maintained its ability to perform its specified design function.

The qualitative visual inspections performed did not show any significant degradation of the liner plate.

Rate of corrosion for one outage is minimal, 0.0025 in/yr.

In 2008, an ILRT was performed on the containment structure

Page 3 of 4 FORM OAR-1 OWNER'S ACTIVITY REPORT and the results of that test showed that the containment structure was performing its specified design function.

Examination results indicate that no appreciable corrosion has occurred since the last ILRT in 2008, so there is no reason to expect the liner plate has degraded to a point of loss of containment integrity.

Based on the chemical comparison performed the leakage source is from internal to the containment. Additionally, the observed high pH is indicative of a low corrosive environment.

Using the general corrosion rate of 0.0025 inches per year and a general wall loss of 0.1875 inches for the base mat liner and cylinder wall liner, a 75 year life is supported .

In summary, based on the examinations, chemistry analysis, design , and the corrosion assessment, reasonable assurance exists to conclude that the liner has maintained the ability to perform its specified design function and that the liner plate is capable of performing its specified design function.

Page 4 of 4 FORM OAR-1 OWNER'S ACTIVITY REPORT TABLE 2 ABSTRACT OF REPAIR/REPLACEMENT ACTIVITIES REQUIRED FOR CONTINUED SERVICE Item Description Date Repair/Replacement Code Class Description Of Work Completed Plan Number Modification of Add Weld-o-let Service Water 40494687-07 3 to contain thru 02/02/2017 line SW-1818- EC 288230 wall leak 001 Modification of Add Weld-o-let Service Water 40516918-03 3 to contain thru 02/11/2017 line SW-1827- EC 288303 wall leak 001