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{{Adams
#REDIRECT [[NL-14-005, Submittal of Relief Request IP3-1SI-RR-07 for Code Case N-770-1 Weld Inspection Frequency Extension]]
| number = ML14017A054
| issue date = 01/13/2014
| title = Indian Point, Unit 3, Submittal of Relief Request IP3-1SI-RR-07 for Code Case N-770-1 Weld Inspection Frequency Extension
| author name = Walpole R
| author affiliation = Entergy Nuclear Northeast
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000286
| license number = DPR-064
| contact person =
| case reference number = NL-14-005
| document type = Letter
| page count = 7
| project =
| stage = Other
}}
 
=Text=
{{#Wiki_filter:Enteray Nuclear Northeast Indian Point Energy Center450 Broadway, GSBP.O. Box 249Buchanan, NY 10511-0249 Tel 914 254 6710Robert WalpoleManagerRegulatory Assurance NL-14-005 January 13, 2014U.S. Nuclear Regulatory Commission ATTN: Document Control Desk11555 Rockville PikeRockville, MD 20852
 
==SUBJECT:==
 
Relief Request IP3-1SI-RR-07 for Code Case N-770-1 Weld Inspection Frequency Extension Indian Point Unit Number 3Docket No. 50-286License No. DPR-64
 
==Dear Sir or Madam:==
Entergy Nuclear Operations, Inc., (Entergy) is submitting Relief Request No. IP3-1SI-RR-07 (Attachment) for Indian Point Unit No. 3 (IP3). This relief request is for the Fourth 10-yearInservice Inspection Interval (ISI).The purpose of this relief request is to extend the inspection of the reactor vessel cold leg nozzle tosafe-end welds (1-4100-16(DM),
1-4200-16(DM),
1-4300-16(DM),
1-4400-16(DM)),
which are Alloy600 welds covered by Code Case N-770-1, Table 1, Inspection Item B. Baseline ultrasonic inspections of these welds were performed in March 2009 and met the Section XI, Appendix VIIIrequirements, including examination volume of essentially 100%. Table 1 of Code Case N-770-1requires volumetric examination of essentially 100% of Inspection Item B pressure retaining weldsonce every second inspection period not to exceed 7 years. Additional circumstances have arisenaffecting the scheduling for this request.The requested extension is until Refueling Outage 20 (3R20) which is scheduled for Spring 2019.This request is made in accordance with 10 CFR 50.55a(a)(3)(i),
an alternative provides anacceptable level of quality and safety.Entergy requests approval of the relief request by August 2014. Performance of this inspection in3R18 would require planning to start at that time.Ao-7 NL-14-005 Docket 50-286Page 2 of 2There are no new commitments being made in this submittal.
If you have any questions or requireadditional information, please contact me at (914) 254-6710.
Sincerely, RW/ai
 
==Attachment:==
 
Relief Request IP3-ISI-RR-07: Code Case N-770-1 Weld Inspection Frequency Extension cc: Mr. Douglas Pickett, Senior Project Manager, NRC NRR DORLMr. William Dean, Regional Administrator, NRC Region 1NRC Resident Inspectors Mr. Francis J. Murray, Jr., President and CEO, NYSERDAMs. Bridget Frymire, New York State Dept. of Public ServiceC ATTACHMENT TO NL-14-005 RELIEF REQUEST IP3-ISI-RR-07:
CODE CASE N-770-1 WELD INSPECTION FREQUENCY EXTENSION ENTERGY NUCLEAR OPERATIONS, INC.INDIAN POINT NUCLEAR GENERATING UNIT NO. 3DOCKET NO. 50-286 Attachment NL-14-005 Docket No. 50-286Page 1 of 4Indian Point Unit 3Fourth 10-year ISI IntervalRelief Request No: IP3-ISI-RR-07 Code Case N-770-1 Weld Inspection Frequency Extension Proposed Alternative In Accordance with 10 CFR 50.55a(a)(3)(i)
-Alternative Provides Acceptable Level of Quality and Safety-1. ASME Code Component(s)
AffectedThe affected component is the Indian Point Unit 3 (IP3) reactor vessel cold leg nozzle to safe-endwelds (1-4100-16(DM),
1-4200-16(DM),
1-4300-16(DM),
1-4400-16(DM))
which are Alloy 600welds covered by Code Case N-770-1, Table 1, Inspection Item B.These welds had an Alloy 600 inside diameter (ID) onlay installed during original fabrication anddo not join any cast stainless steel materials.
Examination Cateaorv Item No. Description CC N-770-1 B Weld 1-4100-16(DM)
Loop 31 cold leg nozzle to safe-end weldCC N-770-1 B Weld 1-4200-16(DM)
Loop 32 cold leg nozzle to safe-end weldCC N-770-1 B Weld 1-4300-16(DM)
Loop 33 cold leg nozzle to safe-end weldCC N-770-1 B Weld 1-4400-16(DM)
Loop 34 cold leg nozzle to safe-end weld2. Applicable Code Edition and AddendaCode Case N-770-1 as referenced in 10CFR50.55a(g)(6)(ii)(F).
: 3. Applicable Code Requirement Table 1 of Code Case N-770-1 requires volumetric examination of essentially 100% ofInspection Item B pressure retaining welds once every second inspection period not to exceed 7years.4. Reason for RequestRelief is being requested at this time to extend the cold leg weld inspections until Refueling Outage 20 (3R20) scheduled for Spring 2019 to allow for this inspection to coincide with theMRP-227-A reactor vessel internals inspections.
Attachment NL-14-005 Docket No. 50-286Page 2 of 4Examination of Item A-2 (Hotleg) and Item B (Coldleg) welds are performed from the insidesurface of the pipe (ID) at IP3 due to limited access provisions from the outside surface of thepipe. The IP3 Item A-2 and Item B welds are located inside a "sandbox" which was installed during original plant construction after all welding was completed.
As a result of physicalinterferences, the ultrasonic examinations of the welds cannot be performed from the outsidediameter (OD). The inspection of the Item A-2 (Hotleg) welds from the ID does not require theremoval of the reactor vessel core barrel, while the inspection of the Item B (Coldleg) weldsfrom the ID does require removal of the reactor vessel core barrel.Baseline inspections of Code Case N-770-1 Inspection Item B welds 1-4100-16(DM),
1-4200-16(DM), 1-4300-16(DM) and 1-4400-16(DM) were performed in March 2009. The ultrasonic examinations performed in 2009 met the Section Xl, Appendix VIII requirements, including examination volume of essentially 100%.Welds 1-4100-16(DM),
1-4200-16(DM),
and 1-4300-16(DM) had no recordable indications.
Weld 1-4400-16(DM) had a recordable circumferential indication in the vicinity of the Alloy 600and stainless steel cladding interface near the dissimilar metal weld. The indication wasdetermined to be entirely embedded in the Alloy 600 clad material and therefore not in theASME Xl Code required examination volume. Since the indication was in the MRP-139examination volume, a conservative approach was used and the indication was assessed interms of the criteria in the ASME Code Section Xl, 1989 Edition, no Addenda, Article IWB-3000, Paragraph IWB-3500 (the code used at the time of inspection).
The indication was found to bewithin the allowable limits specified in IWB-3500 with no further evaluation required.
Since inspection of these welds requires that the core barrel be removed from the reactorvessel, performing these inspections concurrently with the vessel shell weld inspections and thevessel internals inspections required by MRP-227-A during refuel outage in 2019 will result inpersonnel dose savings.
A separate IP3 Relief Request IP3-1SI-RR-06 has been submitted tothe NRC staff to allow deferral of the vessel shell weld inspections from 2015 to 2019.IP3 is currently planning to perform the MRP-227-A (i.e. Vessel Internals) inspections in 3R20(2019) since the actual inspection scope has not yet been finalized (i.e. Entergy is stillperforming internals evaluations in response to NRC RAIs and these evaluations have thepotential to impact the MRP-227-A inspection scope). In addition, a significant pre-outage effortwill be required to finalize inspection tooling and acceptance criteria which cannot be completed prior to 3R1 8 which is currently scheduled to begin in March 2015.5. Proposed Alternative and Basis for Use10 CFR 50.55a(a)(3) states:"Proposed alternatives to the requirements of (c), (d), (e), (f), (g), and (h) of this section orportions thereof may be used when authorized by the Director of Nuclear ReactorRegulation.
The applicant shall demonstrate that:
Attachment NL-14-005 Docket No. 50-286Page 3 of 4(i) the proposed alternatives would provide an acceptable level of quality and safety,or(ii) compliance with specified requirements of this section would result in hardship orunusual difficulty without a compensating increase in the level of quality andsafety."Entergy believes that the proposed alternatives of this request provide an acceptable level ofquality and safety.Indian Point Unit 3 proposes a one time extension to the Code Case N-770-1, Table 1, Inspection Item B, volumetric examinations from a period of 7 years to a period of 10 years. The inspections which are currently required to be performed will be performed not later than March 2019 refueling outage.Based on the Primary Water Stress Corrosion Cracking (PWSCC) crack growth analysis resultsfrom Reference 2, the maximum allowable undetected flaw sizes for the reactor vessel inletnozzle DM welds are tabulated below. These allowable undetected axial and circumferential flaw sizes have been shown to be acceptable in accordance with the ASME Section XI IWB-3640 acceptance criteria through the Spring 2019 RFO taking into account of potential PWSCCcrack growth since the last volumetric examination during the Spring 2009 RFO. In accordance with the detection and sizing requirements in Supplement 10 of ASME Section Xl Appendix VIIIpertaining to the qualification of inspection procedures, the minimum required detectable flawdepth is 10% of the wall thickness (i.e.0.25").
Therefore, based on the current inspection detection capability, these maximum allowable undetected flaw sizes are larger than the flawsizes that could have been reasonably missed during the last volumetric examination of the RVinlet nozzle DM welds in Spring 2009 RFO. As a result, deferring the volumetric examination forthe RV inlet nozzle DM welds from 7 years allowed by Code Case N-770-1 to 10 years istechnically justified.
This is because the maximum allowable undetected flaw sizes that havebeen shown to be acceptable for a service life of 10 years from the Spring 2009 RFO to Spring2019 RFO in accordance with the ASME Section Xl IWB-3640 acceptance criteria are largerthan the flaw sizes that might have been reasonably missed during the Spring 2009 RFO.Maximum Allowable Undetected Flaw SizesAxial Flaw Circumferential Flaw(Aspect Ratio = 2) (Aspect Ratio = 10)Percent through wall (a/t) 0.38 0.41Flaw Depth (inches) 0.95 1.025Flaw Length (inches) 1.90 10.25Minimum Detection 0.25 0.25Capability (inches)
Attachment NL-14-005 Docket No. 50-286Page 4 of 46. Duration of Proposed Alternative This request is applicable to Entergy's inservice inspection program for the fourth interval forIndian Point Unit 3. The proposed alternative is until March 2019.7. References
: 1. Code Case N-770-1, Alternative Examination Requirements and Acceptance Standards for Class 1 PWR Piping and Vessel Nozzle Butt Welds Fabricated with UNS N06082 orUNS W86182 Weld Filler Material With or Without Application of listed Mitigation Activities Section XI, Division 1.2. Westinghouse LTR-PAFM-1 3-115-P Rev. 0, "Technical justification to Support ExtendedVolumetric Examination Interval for Indian Point Generating Station Unit 3 Reactor InletNozzle to Safe End Dissimilar Metal Welds," dated November, 2013.}}

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