NL-18-1480, Response to NRC Request for Additional Information on Alternative Request (HNP-ISI-ALT-05-04)
| ML18333A382 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 11/29/2018 |
| From: | Gayheart C Southern Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| HNP-ISI-ALT-05-04, NL-18-1480 | |
| Download: ML18333A382 (19) | |
Text
3535 Colonnade Parkway Birmingham, AL 35243 205 992 5316 tel 205 992 7601 fax cagayhea@southernco.com Cheryl A. Gayheart Regulatory Affairs Director November 29, 2018 Docket Nos.: 50-321 NL-18-1480 50-366 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Edwin I. Hatch Nuclear Plant Response to NRC Request for Additional Information on Alternative Request HNP-ISI-ALT-05-04 Ladies and Gentlemen:
By letter dated June 21, 2018 (Agencywide Documents Access and Management System Accession No. ML18172A281), Southern Nuclear Operating Company (SNC) submitted proposed Alternative Request No. HNP-ISI-ALT-05-04 (Proposed Alternative) to certain requirements of the American Society of Mechanical Engineers, Boiler and Pressure Vessel Code (ASME Code), for the fifth 10-year Inservice Inspection (ISI) Program for the Edwin I. Hatch Nuclear Plant, Units 1 and 2 (Hatch). Specifically, pursuant to Title 10 of the Code of Federal Regulations (10 CFR) paragraph 50.55a(z)(1), SNC requested approval to implement alternative BWRVIP Guidelines in lieu of ASME Code Section XI Table IWB-2500-1 Examination Category B-N-1 and B-N-2 requirements. The proposed alternative applies to the fifth ISI interval for Hatch. SNC is requesting NRC authorization of this alternative on the basis that the proposed alternative will provide an acceptable level of quality and safety.
The NRC staff has reviewed the information provided by SNC and determined that additional information is needed to complete its evaluation. The enclosure provides the SNC response to the NRC request for additional information.
This letter contains no NRC commitments. If you have any questions, please contact Jamie Coleman at 205.992.6611.
Respectfully submitted, CAG/RMJ
Enclosure:
SNC Response to NRC Request for Additional Information Cc:
Regional Administrator, Region ll NRR Project Manager - Hatch Senior Resident Inspector - Hatch RTYPE: CHA02.004
Edwin I. Hatch Nuclear Plant Response to NRC Request for Additional Information on Alternative Request HNP-ISI-ALT-05-04 Enclosure SNC Response to NRC Request for Additional Information
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-1 NRC Request for Additional Information 10 CFR 50.55a(g)(4) requires inservice inspection of ASME Code Class 1 components to be performed in accordance with Section XI of the ASME Code. The licensee has proposed an alternative to the inspection requirements of Section XI for ASME Code Class 1, Examination Category B-N-1 and B-N-2 components. Although the NRC has determined that BWRVIP alternatives may be used for inspection of Category B-N-1 and B-N-2 components, the NRC staff must review the inspection history of these components in order to determine that they are bounded by the proposed alternative. Therefore, NRC staff requests that the licensee submit an inspection history for the components for which an alternate inspection was requested.
SNC Response to NRC Request for Additional Information The following tables provide the requested inspection history:
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-2 Hatch Unit 1 Component Inspection Date Type Inspection Results Core Shroud Horizontal Welds NA NA Installed four Shroud Tie Rods in 1994 which exempts horizontal welds H-1 through H-8 from inspection.
Spring 2006 UT Examined H-1 through H-7 to prove structural integrity due to cracked shroud tie rod upper supports and one loose shroud tie rod. Significant cracking identified, but acceptable for one cycle.
Spring 2008 UT Examined H-5, H6a, H6b, and H-7 to prove structural integrity due to the inability to replace cracked shroud tie rod upper support at 225. Significant cracking identified, but acceptable for another cycle. Little growth in flaws from 2006 inspection.
Spring 2016 EVT-1 Examined H4 from the OD and the ID from 65° to 115° for extent of condition due to Spring 2014 shroud vertical weld and weld intersection results. Several transverse indications identified originating from H4 upper and lower weld toes, some extending beyond HAZ. Longest flaw 1.65". One at cell 50-35 (106°) verified through wall. Two flaws presumed through wall, for evaluation. All newly discovered flaws determined structurally acceptable and bounded by 1R26 structural and leakage evaluation.
Spring 2018 EVT-1 Examined H4 from the OD and the ID from 235° to 245°. The 235° - 245° locations have several off-axis flaws that are extending above and below H4 from the ID ranging from < 0.5 to 1.09 in length at the 230°, 242°, 245°, and 247°. Two indications were noted on the OD at 228° and 232°, extending above H4, with a maximum length of 1.27. No flaws aligned on the OD and ID, and therefore none of the indications were through wall flaws. From the ID locations of the 335° - 345°, several off-axis flaws were noted above and below H4 ranging from 0.42 and 1.77 in length. No indications were observed from the OD. All newly discovered flaws determined structurally acceptable and bounded by latest structural and leakage evaluation.
Core Shroud Tie Rods Spring 2006 Tightness, EVT-1, VT-3 Tightness checks to all four Tie Rods. One at 315° was again found to be less than desirable load and was corrected. Two cracked upper supports at 135° & 225°, one at 135° was replaced. Additional repairs and/or modifications to be performed next outage.
Spring 2008 Tightness, EVT-1, VT-3 Replaced two tie rod upper supports at 135° and 315°. Unsuccessful in detensioning the Tie Rod nuts at 45° and 225°. 45° and 225° tie rod assemblies were restored to a condition acceptable for another cycle. Tie rod at 225° contains a flaw which grew at a rate less than predicted for the previous fuel cycle.
Spring 2010 Tightness, EVT-1, VT-3 Successfully replaced the remaining two tie rod assemblies 45° and 225°. Tightness checks performed at all four tie rods.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-3 Hatch Unit 1 Component Inspection Date Type Inspection Results Core Shroud Tie Rods Spring 2012 VT-3 EVT-1, VT-1 One-cycle post-installation re-inspection of all four tie rod assemblies, including post-torque verifications and upper spring torsion arms/bolts. No recordable indications.
One-cycle post installation re-inspection of all four tie rod upper support corners. No recordable indications.
Spring 2016 VT-3 Conducted VT-3 exams of Tie Rod/Core Plate Wedges Assemblies at 45°, 135°, 225°,
and 315° with satisfactory results. No recordable indications.
Spring 2018 VT-3 No recordable indications - Performed examinations of all four (4) Torsion Arms &
Torsion Arm Bolts (45°, 135°, 225°, 315°).
Core Shroud Vertical Welds Spring 2008 EVT-1 Examined V1, V2, V3, V4, V7, V8 V9, V10, and V11. Short indications recorded on the ID at the intersections of H4 with V4 and at the intersections of H5 with V7 and V8.
Spring 2010 EVT-1 Examined 12 on either side of high fluence intersections from the ID, including V7/H5, V8/H5, V4/H4, V5/H5, V5/H4, V6/H4, and V6/H5 intersections. One new indication reported at V5/H5, one less indication at V4/H4 compared to 2008 outage results.
Also examined V12, V13, and V14 from the shroud OD with no indications reported.
Spring 2014 UT UT EVT-1 Examined V3, V4, V5, V6, V7, V8, V9, and V10, via UT. Indications noted at V4, V5, V6, V7 and V8. Re-examination of V6 revealed a portion of the longest V6 crack was through-wall. Another small indication near V5 above H4 not associated with a weld was sized via UT. All evaluated structurally and for leakage and found acceptable.
Examined intersections of H4/V4, H5/V8, and H5/V7 via traditional or specialized UT to characterize previously reported off-axis indications. Four indications axial to H4 near the V4 intersection were found to be through wall. All evaluated structurally and for leakage and found acceptable.
Intersections at H4/V4 and H5/V8 were also inspected via EVT-1 from the ID.
Additional small indications noted at both intersections evaluated as acceptable.
Additional coverage CCW of V4 at H4 revealed an additional axial indication (one of the four H4/V4 through-wall indications identified via UT). Examined V1, V2, and V11 via EVT-1 from the OD with no recordable indications. All evaluated as acceptable.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-4 Hatch Unit 1 Component Inspection Date Type Inspection Results Core Shroud Vertical Welds Spring 2016 EVT-1 Conducted supplemental EVT-1 exam of V5 and V6 from the OD. Pre-existing IGSCC flaws at V5 and V6 showed no growth based on review of 1R26 UT. One 1.4" transverse flaw identified extending from V6 weld toe. All flaws determined structurally acceptable. Examined V12, V13, V14 from the OD with no recordable indications, re-examine in 6 years. See Shroud Horizontal Weld scope above for additional H4 inspection results.
Spring 2018 EVT-1 No recordable Indications - Performed re-examinations from the OD surface of welds V-12, V-13, and V-14 in accordance with Deviation 2017-01. Achieved 75% coverage for V12 and 85% coverage for V13, V14.
Core Shroud Ring Segment Welds Spring 2006 EVT-1 EVT-1 from OD of Top Guide RSW at 120°. No recordable indications. One of four Top Guide RSW every 2 cycles, or 4 years.
Spring 2010 EVT-1 EVT-1 from OD to Top Guide RSW at 240°. No recordable indications. One of four Top Guide RSW every 2 cycles, or 4 years.
Spring 2014 EVT-1 EVT-1 from OD of Top Guide RSW (R-12) at 300°. No recordable indications. One of four Top Guide RSW every 2 cycles, or 4 years.
Spring 2018 EVT-1 Top Guide Support Ring Segment Weld at 60° R-8 from outside surface. No recordable Indications.
Core Shroud Support Ledge (H-9)
Spring 2006 EVT-1 VT-3 UT EVT-1 of >15% of H-8 in order to establish redundancy to the degraded shroud repair (two cracked upper supports at 135°& 225°). No recordable indications.
ASME VT-3 of all shroud support plate gussets and attachment welds.
UT of approximately 20% of H-9 per BWRVIP-104. No recordable indications.
Spring 2010 EVT-1 VT-3 EVT-1 of Shroud Support Plate Gusset Welds at 30°, 45°, 90°, 135°, 210°, 225°, 300°,
315°, 345° per BWRVIP-38 requirements.
VT-3 of 30°, 90°, 210°, 300°, 345° for ASME requirements.
Spring 2016 EVT-1 VT-3 EVT-1 of Shroud Support Plate Gusset Welds at 60°, 120°, 150°, 240°, 330° per BWRVIP-38 requirements, and Tie Rod Anchorages/Gussets at 45°, 135°, 225°, and 315°.
VT-3 of Shroud Support Plate Gusset Welds at 15°, 45°, 60°, 75°, 105°, 120°, 135°,
150°, 165°, 195°, 225°, 240°, 255°, 270°, 285°, 315°, 330° for ASME requirements.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-5 Hatch Unit 1 Component Inspection Date Type Inspection Results UT UT examination of approximately 15% of H-9 was conducted. No recordable indications.
Core Shroud Support Ledge Access Hole Covers Spring 2006 VT-1 & VT-3 Examine each period. Examined 0° and 180 Evidence of expected leakage.
Spring 2014 VT-1 & VT-3 Examine once per 8 years per BWRVIP-180. Examined AHCs at 0 and 180.
Evidence of expected leakage. No changes noted.
Core Spray Internal Piping Spring 2006 EVT-1 No indications.
Spring 2008 EVT-1 No indications.
Spring 2010 EVT-1 No indications.
Spring 2012 EVT-1 No indications.
Spring 2014 EVT-1 No indications.
Spring 2016 EVT-1 No indications.
Spring 2018 EVT-1 No recordable indications. Transitioned to BWRVIP-18 Rev 2A Inspection Requirements. Performed inspections of the P4a, P4b, P4c, and P4d welds at 350°.
Discovered Core Spray Pipe draw beads near P4b.
Core Spray Sparger Spring 2006 EVT-1 &
VT-3 No recordable indications.
Spring 2008 EVT-1 No recordable indications.
Spring 2010 EVT-1, VT-1(89) &
VT-3 No recordable indications.
Spring 2012 EVT-1 &
VT-1(89)
No recordable indications.
Spring 2014 EVT-1 &
VT-1(89)
No recordable indications.
Spring 2018 VT-1(89)
VT-3 No recordable Indications - Transitioned to BWRVIP-18 Rev. 2-A Inspection Requirements. Inspected Core Spray Sparger Repair Clamp (Bolting and Tack Welds) at 350°.
No recordable Indications - All (A-D) Sparger Nozzles (S3a/b) and Sparger D Drain Connections (S3c).
Top Guide Spring 2006 VT-1 VT-1, two of four Top Guide Hold-downs, 180° apart every other outage. Also performed VT-1 of two cells from the underside. No recordable indications.
Spring 2008 EVT-1 Grid beams in 14 cells per BWRVIP-183. No recordable indications.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-6 Hatch Unit 1 Component Inspection Date Type Inspection Results Top Guide Spring 2010 EVT-1 &
VT-1 EVT-1 of grid beams in 21 cells per BWRVIP-183. VT-1 on two of four top guide hold-downs, 180° apart, every other outage. No recordable indications.
Spring 2014 VT-1 VT-1, two of four Top Guide Hold-downs, 180° apart every other outage. Minor wear noted on 176 assembly at pin area. Evaluated as acceptable.
Spring 2016 VT-1 VT-1, Reinspection of Top Guide Hold-down at 176. No noted changes in wear, acceptable.
Spring 2018 VT-1 Performed examinations of the Top Guide Hold Down Bracket and Attachment Welds to the Shroud at 86°, 176°, and 266°. A previously undocumented indication (from the Spring 2010 Refueling Outage (1R24)) was noted on the 086° top guide hold down assembly. The indication will be reinspected during 1R29 to reassess the growth rate.
Performed examinations of the Top Guide Beam Connection. Two indications were found on the top guide beam connection at cell 46-11. Based on these findings, expanded scope to all accessible top guide beam connection locations. Cumulative inspections resulted in newly discovered indications on the top guide bottom support ring at 30°, 40°, 50°, 130°, 140°, 220°, 310°, and 320° locations, and on the bottom collars at 50°, 130°, 220°, 230°, and 310° locations. All indications evaluated as acceptable for one cycle of operation. 1R29 top collars are to be inspected to ensure evaluation assumptions remain bounded.
Core Plate Spring 2006 VT-3 Two cell locations during CRB exchange. Also four Core Plate By-pass Flow Hole Plugs. No recordable indications. Examinations scheduled when CRBs are exchanged.
Spring 2008 VT-3 Examined 10 Core Plate Bypass Plugs.
Spring 2010 VT-3 Examined 21 Core Plate Bypass Plugs. No recordable indications reported.
Spring 2014 VT-3 Examined 34 Core Plate Bypass Plugs. No recordable indications or leak by reported.
Spring 2016 VT-3 Examined 17 Core Plate Bypass Plugs. No recordable indications reported.
Spring 2018 VT-3 Examined 17 Core Plate Bypass Plugs. No recordable indications reported.
SLC Spring 2006 Direct VT-2 or UT Performed direct VT-2 during leakage test. Access not suitable for UT. No recordable indications.
Spring 2008 Direct VT-2 or UT Performed direct VT-2 during leakage test. Access not suitable for UT. No recordable indications.
Spring 2010 UT Performed UT using newly developed tooling allowing access. No recordable indications.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-7 Hatch Unit 1 Component Inspection Date Type Inspection Results Jet Pump Assembly Spring 2006 Spring 2006 EVT -1 VT-1 EVT-1 &
VT-1 EVT-1 was performed on 50% of the RS-1, RS-2, RS-3 welds. Indications on the two thermal sleeve to elbow welds (RS-1s) that were first reported in 1997 and re-examined in 1999, 2000 and 2004 had no significant changes since 1997.
Re-baseline all 20 restrainer wedge bearing surfaces (WD-1) - No recordable indications.
Re-examined all wedges. Completed baseline of medium priority locations. Re-examined 50% of RB-1 locations. No recordable indications.
Spring 2008 EVT-1 VT-1 UT Re-examined RS-1 indications on JP 3/4 and 7/8 with no change in length.
Examined sensing lines on JPs 7 and 17. No recordable indications.
UT was performed on 50% (10 Jet Pumps) of AD-1, AD-2, & DF-2 in accordance with BWRVIP-41 Rev. 2. No recordable indications.
VT-1 Re-examined RS-1 indications on JP 3/4 and 7/8 with no change in length. Examined RS-8 and RS-9 welds for Jet Pumps 1-10. No recordable indications.
Examined RB-1, riser braced to vessel welds, for Jet Pumps 5/6 and Jet Pumps 9 through 18. No recordable indications.
Spring 2012 EVT-1 VT-1 Examined RS-1, RS-2, RS-3 riser welds for JP 11-20. Re-examined RS-1 indications on JP 3/4 and 7/8 with no change in length.
Examined all 20 JP restrainer bracket wedges.
Examined sensing lines on JP 7 and 17. No recordable indications.
Spring 2014 EVT-1 Re-examined RS-1 indications on JP 3/4 and 7/8 with no change in length. Re-examined 25% (five Jet Pumps) of MX-2, IN-4, RS-6 and RS-7, and DF-1 welds according to BWRVIP-41 Rev 3, with no indications noted. Also examined Riser brace to yoke (RB-2) welds for four jet pumps with no indications noted.
Spring 2016 EVT-1 Re-examined RS-1 indications on JP 3/4 and 7/8 with no change in length.
Examined RS-8 and RS-9 welds for Jet Pumps 11-16. Expanded scope to RS-8/9 on JP riser 5/6 due to large set screw gap and wedge rod wear at JP 5 and 6 respectively. No recordable indications.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-8 Hatch Unit 1 Component Inspection Date Type Inspection Results Jet Pump Assembly Spring 2016 VT-1 VT-1 UT Re-examined WD-1 for Jet Pumps 1-20, slight wedge rod wear (less than 1%) found at WD-1 for Jet Pump 6 and was evaluated as acceptable for plant operation. Expanded scope to WD-2 and AS-2a/b for Jet Pump 5 & 6 due to large set screw gap and wedge rod wear at JP 5 and 6 respectively. No other recordable indications.
Examined 100% AS-1 locations. Restrainer bracket set screw gaps identified at nine jet pumps. The largest gaps noted at Jet Pumps 5 & 15 (23 and 18 mils respectively) were eliminated via wedge tapping. The as-left condition of all gaps were evaluated and determined acceptable for continued plant operation.
In accordance with BWRVIP-41, UT was performed on 50% (10 Jet Pumps) of AD-1, AD-2, & DF-2 and 100% (20 Jet Pumps) of BB-1, BB-2, & BB-3. No recordable indications.
Spring 2018 EVT-1 VT-1 Performed re-inspections of 40% of the RB-1 welds (4/10 locations). Performed re-inspections (EVT-1) on 50% of the RS-1, RS-2, and RS-3 Welds. No changes to previous indications at JP-3/4 and JP-7/8 RS-1 welds. Performed AS-1a (Vessel Side), AS-1b (Shroud Side) for JP-5, 10, and 15. Restrainer bracket set screw gaps identified at three jet pumps. The largest gaps noted at Jet Pumps 5 & 10 (14 mils at both locations). The as-left condition of all gaps were evaluated and determined acceptable for continued plant operation.
No recordable indications - Performed re-inspections of five (5) Jet Pump WD-1 locations (25%) and two (2) Jet Pump Sensing Line Brackets.
CRD Guide Tubes Spring 2018 VT-3 No Indications - Inspected six (6) Fuel Support / Guide Tube Anti-Rotation Pins from the top of core plate during core plate plug exams.
Note - CRGT-1, and anti-rotation pin welds are inspected via VT-3, and CRGT-2, 3 are inspected via VT-1 (10% sample) if made accessible during maintenance.
Dry Tubes Spring 2006 N/A Replaced 6 (50%) dry tubes.
Spring 2008 N/A Replaced 6 (50%) dry tubes.
RPV Interior Attachments Spring 2006 EVT-1 Three Lower Surveillance Specimen brackets to RPV.
Spring 2008 EVT-1 &
VT-3 Four FW Sparger Bracket Welds to RPV. No indications.
Spring 2010 EVT-1 &
VT-3 One Core Spray Bracket to RPV weld at 330°. No indications.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-9 Hatch Unit 1 Component Inspection Date Type Inspection Results RPV Interior Attachments Spring 2012 Spring 2012 VT-3 EVT-1 &
VT-3 One Upper guide rod bracket to RPV at 180°, and two Guide Rod & Lower guide rod attachment welds to Shroud at 0° and 180°. No recordable indications.
Steam Dryer Support Bracket & Attachment welds (4). No indications.
Core Spray Piping Bracket at 210° also inspected. No indications.
Spring 2014 Spring 2014 VT-3 EVT-1 &
VT-3 Steam Dryer Hold Down Brackets (4). No recordable indications.
Core Spray Bracket & Attachment welds at 30°. No recordable indications.
Spring 2016 EVT-1 &
VT-3 Examined one Core Spray Bracket & Attachment weld at 150°, and four FW Sparger Bracket Welds to RPV. No recordable indications.
Spring 2018 VT-3 EVT-1 No recordable Indications - Guide Rod and Lower Guide Rod Bracket Attachment Weld to RPV at 0°. Upper and Lower surveillance specimen bracket attachment welds to the RPV (30°, 120°, & 300°). Interim inspection guidance within BWRVIP Letter 2018-045 was completed for 120° upper, lower surveillance specimen brackets, basket, rod, etc. This is the only location with a capsule remaining in vessel.
No recordable Indications - Core Spray Piping Bracket and Attachment Welds to RPV at 330° location.
LPCI Coupling N/A N/A Not applicable to Edwin I. Hatch Nuclear Plant Unit 1.
Feedwater Spargers Spring 2006 VT-1 & VT-3 Sparger Arms, Flow Holes, Brackets, Tees, Welds. Unusual wear on end brackets to pins. Probable repair next outage. Schedule two of four every other outage beginning 1R20.
Spring 2008 VT-3 New FW Sparger end bracket repair assemblies installed at four locations (185°, 265°,
275°, & 355°) due to wear.
Spring 2010 VT-3 FW Sparger end pins/brackets at 5°, 85°, 95°, 175° inspected. Minor wear discovered on locations at 95° and 175°. Scope expanded to examine repaired locations at 185°,
265°, 275°, 355°. No further wear noted from additional exams. Re-examine locations at 5°, 85°, 95°, and 175° next outage with contingency planning in place.
Spring 2012 VT-1 & VT-3 EVT-1 &
VT-3 FW Sparger end pins/brackets at 5°, 85°, 95°, 175° re-inspected. No further wear noted from reinspection. Re-examine or repair next outage.
Previously repaired FW sparger end pin brackets at 265°, 185°, 355°, 275° also inspected with no indications noted.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-10 Hatch Unit 1 Component Inspection Date Type Inspection Results Feedwater Spargers Spring 2014 VT-3 EVT-1 &
VT-3 EVT-1 &
VT-3 Sparger Arms, Flow Holes, Brackets, Tees, Welds. One flow nozzle discovered slightly out of round. Evaluated as acceptable. No other recordable indications Modified FW Sparger end pins/brackets at 185°, 265°, 275°, 355° re-inspected. No recordable indications.
FW Sparger end pins/brackets at 5°, 85°, 95°, 175° re-inspected. No further wear noted from reinspection. Re-examine or repair next outage.
Spring 2016 VT-3 VT-1 & VT-3 EVT-1 &
VT-3 Sparger Arms, Flow Holes, Brackets, Tees, Welds. Flow nozzle at 315° re-inspected.
No recordable changes.
FW Sparger end pins/brackets at 5°, 85°, 95°, 175° re-inspected. No further wear noted from reinspection.
End bracket attachment welds at 185°, 265°, 275°, 355° re-inspected. No recordable changes.
Spring 2018 VT-3 VT-1 & VT-3 Sparger Arms, Flow Holes, Brackets, Tees, Welds. Flow nozzle at 45° & 135° re-inspected. No recordable changes.
FW Sparger End Pins/Brackets at 85°, 95°, 175° re-inspected. The inspections resulted in: (1) minor new wear being identified on the 085° pin, (2) no discernible change in previously identified (during the Spring 2010 Refueling Outage (1R24)) wear on the 095° pin, and (3) a slight change in previously identified (during 1R24) wear on 175° pin. All indications evaluated for continued operation with re-inspection per NUREG 0619.
Steam Dryer Spring 2006 VT-1 & VT-3 Upper support ring @ 0°-360° top and vertical surfaces VT-3. Lower & Upper Guide at 1800 (10) Tie Bars TB1 - TB10, Vertical welds - Various Hood (8) Drain Channels DC1 - DC8 (5) Lower horizontal welds (2) Upper horizontal welds. One tie bar was cracked on one side on the middle span and was repaired (re-welded). Minor indications on DC-1 & Upper Support Ring were evaluated as acceptable. BWRVIP examinations are performed every other cycle until the BWRVIP determines an examination frequency. Other owner designated examinations are performed every 6 years.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-11 Hatch Unit 1 Component Inspection Date Type Inspection Results Steam Dryer Spring 2008 VT-1 (89)
Upper support ring top and vertical surfaces 0-360°. Monitoring previously identified small indications. Flaws exhibited little discernable change.
Lower support ring and guide 24 on either side of lower guide at 0°. Drain channel #1.
Monitoring previously identified small indications. Flaws exhibited little discernable change. Repaired tie bar #6 inspected with no indications.
Spring 2010 VT-1 (89)
Upper support ring top and vertical surfaces 0-360°. Previously identified indications were determined to be non-relevant during 1R24. Flaws exhibited little discernable change.
Spring 2012 VT-1 (89)
Examined steam dryer tie bars 3-7, various horizontal welds (4), vertical partition welds (4), Vertical hood welds (9), and drain channels (4). No indications.
Spring 2014 VT-1 (89)
Lower support ring 24 on either side of lower guide at 0°. Upper guide and lower guide at 0°. Seismic Brackets (4). Lifting Eye, Rod and Attachment welds at 215° and 325°. No indications.
Vertical partition weld (1) - no change to historical/legacy indications.
Spring 2016 VT-1 (89)
Inspected Upper Support Ring top and vertical surfaces 0°-360°, Lower support ring 24 on either side of lower guide at 180°, Vertical Partition Welds (3), Various Horizontal Welds (3), Vertical Hood Welds (10), with no indications.
Upper and Lower Guides at 0° and 180° inspected. No change to pre-existing gouges and areas of raised metal at 180° Lower Guide. Acceptable for continued operation.
Drain Channel welds 1-7 inspected. No change to pre-existing indications at Drain Channel #1. No other indications reported.
Seven Tie Bars inspected. Tie Bar #6 repairs showed no change. Tie Bars 7 & 8 show crack-like indications. Evaluated as acceptable for 1-cycle of operation. Repairs to be planned next outage.
Spring 2018 VT-1 (89)
Tie Bars 3, 4, 5, 6, 7, and 8 were inspected. There were no new indications noted on Tie Bars 3-8 or changes to existing indications on Tie Bars 7 and 8.
Two newly identified indications at vertical partition weld on the end plate base material of the Steam Dryer (beginning in the heat affected zone (HAZ) of the Steam Dryer Vertical Partition Plate (VP) 3/2-4 Weld) were evaluated as acceptable.
Repaired Items - Upper and Lower Guides at 0° and Tie Bars 7 and 8.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-12 Hatch Unit 2 Component Inspection Date Type Inspection Results Core Shroud Horizontal Welds N/A N/A Note: Installed four Shroud Tie Rods in 1995 which exempts horizontal welds H-1 through H-8 from inspection.
Core Shroud Vertical Welds Spring 2007 EVT-1 Performed EVT-1 examinations from the outside surface for welds V-1, V-2, V-9, V-10, & V-11. No recordable Indications. V-6 Inside surface indication was found in 2005 on at the upper intersection (H-4) which parallels H-4. Was re-examined to determine if this indication had changed. No changes were recorded.
Spring 2011 EVT-1 Performed EVT-1 examinations from the outside surface for welds V-12, V-13, and V-14. No recordable indications.
Spring 2013 EVT-1 Performed EVT-1 examinations from the outside surface for welds V-1, V-2, V-9, V-10, & V-11. No recordable Indications.
Spring 2015 EVT-1 VT-3 Performed EVT-1 examinations from ID and OD on V3, V4, V5, V6, V7, V8. Several recordable indications noted near V3 and V6. Corresponding outside diameter locations were examined with no recordable indications. All indications evaluated as acceptable for return to service per BWRVIP-76 guidance and ASME SCXI rules as applicable.
Performed ASME SCXI VT-3 shroud inside surface exams from shroud flange to support ledge for approximately 270 degrees, and from top guide support ring to shroud flange for 90 degrees. Several recordable indications noted at three additional locations from the inside diameter. Corresponding outside diameter inspections revealed no recordable indications. All indications evaluated as acceptable for return to service per BWRVIP-76 guidance and ASME SCXI rules as applicable.
Spring 2017 EVT-1 Performed examinations from the OD surface of welds V-12, V-13, and V-14. No recordable indications.
Core Shroud Ring Segment Welds N/A N/A Edwin I. Hatch Nuclear Plant (Unit 2) does NOT have Ring Segment Welds Core Shroud Tie Rods Spring 2007 EVT-1 &
VT-3 (Tightness)
All Tie Rods - No indications. Upper Supports & Tie Rod Nuts have been determined to be susceptible to IGSCC. This will make corrective action necessary by next outage.
Spring 2009 EVT-1 &
VT-3 All four tie rod assemblies modified with replacement component items designed to not be susceptible to IGSCC. All component items replaced with the exception of the lower collet and clevis pin.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-13 Hatch Unit 2 Component Inspection Date Type Inspection Results Core Shroud Tie Rods Spring 2011 EVT-1 &
VT-3 Post tie-rod modification inspections on all four tie rods were successfully performed with no indications noted.
Spring 2017 VT-3 Performed examinations on all four Core Plate Seismic Wedges associated with the Shroud Tie Rods (45°, 135°, 225°, and 315°). No recordable indications.
Core Shroud Support Spring 2007 VT-3 EVT-1 VT-1 & VT-3 H-9: Examined 100% of accessible surfaces from top per BWRVIP-38. No indications.
H-8: EVT-1 of accessible weld surface from the top side of H8. No indications.
AHC: VT-3 of 0° and 360° access hole covers with VT-1 of tack welds. No indications.
Spring 2015 VT-1 & VT-3 AHC: VT-3 of 0° and 360° access hole covers with VT-1 of tack welds. No indications.
Spring 2017 VT-3 H-9: Performed examinations on 70% of all accessible surfaces (from top) per BWRVIP-38. No recordable indications.
Core Spray Sparger Spring 2009 EVT-1 &
VT-1 New sparger bracket-to-shroud indication at 272°. Previous sparger bracket-to-shroud indications tracked since 1994 remain unchanged. New indication recorded is acceptable and similar to previous indications.
Spring 2011 VT-1 Reinspection of sparger bracket-to-shroud indication at 272°. Additional indications noted in the same area, similar to previous indications. This indication is thought to be older and revealed due to more efficient cleaning methods used for the first time in this area. All other bracket locations were inspected in 2009 with no changes since 1994.
Spring 2013 EVT-1 &
VT-1(89)
EVT-1 of all sparger major piping welds (S1, S2, & S4). VT-1 (89) of all sparger bracket (SB) locations and 50% of sparger nozzle welds. Newly discovered indication at 330° sparger bracket (weld 50), bounded by previous evaluations, and similar to findings Spring 2011, thought to be older and revealed due to more efficient cleaning methods used for the first time in this area. No changes noted for any other previous indications.
Spring 2015 VT-1(89)
VT-1 (89) Reinspection of core spray sparger bracket to shroud welds at 272° and 330°. No changes to indications at 272°. Evaluated as acceptable. No indications reported at 330°.
Spring 2017 VT-1(89)
Transitioned to BWRVIP-18 Rev. 2-A Inspection Requirements. Reinspection of Core Spray Sparger Bracket to Shroud Welds at 272° and 330° and the remaining sparger bracket locations with previous Indications. No discernible changes were noted. New indications were found at 60° (Weld 8), 240° (Weld 36), and 330° (Weld 51), and all
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-14 Hatch Unit 2 Component Inspection Date Type Inspection Results were evaluated as acceptable. The new indications will be reinspected during the next two refueling outages (2R25 and 2R26).
Core Spray Internal Piping Spring 2007 EVT-1 Reinspection per BWRVIP-18. No Indications.
Spring 2009 EVT-1 Reinspection per BWRVIP-18. No Indications.
Spring 2011 EVT-1 Reinspection per BWRVIP-18-A. No Indications.
Spring 2013 EVT-1 Reinspection per BWRVIP-18 Rev. 1-A. No indications.
Spring 2015 EVT-1 Reinspection per BWRVIP-18 Rev. 1-A. No indications.
Spring 2017 EVT-1 Transitioned to BWRVIP-18 Rev. 2-A Inspection Requirements. Performed inspections (EVT-1 and VT-3) of the Core Spray Piping Bracket to RPV Welds at 30° and 210° and inspections (EVT-1) of P4a, P4b, P4c, and P4d Welds at 170°. No recordable indications.
Core Plate N/A N/A No BWRVIP inspections are required. Core Plate wedges installed in 1995.
SLC Spring 2015 UT N10 Safe-end & Extension exam per ASME Supplement 10. No indications.
CRD Guide Tubes NA NA Note - CRGT-1, and anti-rotation pin welds are inspected via VT-3, and CRGT-2, 3 are inspected via VT-1 (10% sample) if made accessible during maintenance.
Dry Tubes Spring 2007 N/A Replaced six (50%) dry tubes.
Spring 2009 N/A Replaced six (50%) dry tubes.
Top Guide (U2 has Wedges)
Spring 2007 VT-1 Grid/beams: SIL-554, Examined bottom surfaces of 14 cells. No indications.
Spring 2009 VT-1 Hold Downs and Attachments to the shroud (two of four) 180° apart every other outage. No recordable indications.
Spring 2011 EVT-1 Grid/Beams: BWRVIP-183. Examined bottom 2 from sides and grid beam intersections of eight cells. No indications.
Spring 2013 VT-1 Hold Downs and Attachments to the shroud (two of four) 180° apart every other outage. No recordable indications.
Spring 2015 EVT-1 Grid/Beams: BWRVIP-183. Examined bottom 2 from sides and grid beam intersections of 8 cells. No indications.
Spring 2017 VT-1 Recordable Indication - Performed examinations of the Top Guide Hold Down Bracket and Attachment Welds to the Shroud at 86° and 266°. A new indication was found at the 86° azimuth and was evaluated as acceptable for continued operation.
The indication will be reinspected during 2R25 to reassess the growth rate.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-15 Hatch Unit 2 Component Inspection Date Type Inspection Results LPCI Coupling N/A N/A N/A - Not Applicable to Edwin I. Hatch Nuclear Plant Unit 2.
Jet Pump Assembly Spring 2007 EVT-1, VT-1
& UT Performed VT-1 100% of the WD-1s. Performed 100% UT of BB-1, BB2, & BB-3.
Performed EVT-1 50% of RS-8 to RS-9s, IN-4s, MX-2s, DF-1s, RS-6s & RS-7s. No indications.
Spring 2009 EVT-1 &
VT-1 Performed second 50% reinspection of RS-1, RS-2, RS-3, DF-2, AD-1, & AD-2.
Inspected two RB-1 locations. No indications.
Spring 2011 EVT-1 &
VT-1 Performed VT-1 of 100% of the WD-1 population. Performed EVT-1 of 100% of RS-8 to RS-9 welds. Performed EVT-1 of four total RB-1 weld locations and three total RB-2 weld locations. Performed VT-1 of two jet pump sensing line brackets. No recordable indications.
Spring 2013 EVT-1 &
VT-1 Performed EVT-1 re-inspection of 25% of IN-4s, MX-2s, DF-1s, RS-6s & RS-7s. No indications.
Spring 2015 EVT-1 &
VT-1 Performed EVT-1 re-inspection of 50% of RS-1, RS-2, RS-3, DF-2, AD-1 and AD-2 welds, as well as 25% of RB-1 welds. Performed VT-1 of 100% of WD-1 population.
No indications. Also performed VT-1 of 100% of AS-1 population, with minor set screw gaps noted at six Jet Pumps evaluated as acceptable.
Spring 2017 EVT-1, VT-1
& UT Performed re-inspections (VT-1) of five Jet Pump WD-1 Locations (25%) and two Jet Pump Sensing Line Brackets. Additionally, performed re-inspections (EVT-1) of 25%
of the RS-8/9 Welds and the RB-2a, RB-2b, RB-2c, & RB-2d Welds. Finally, performed re-inspections (UT) on 100% of the BB-1, BB-2, and BB-3 Welds. No recordable indications.
RPV Interior Attachments Spring 2007 VT-3 All Guide Rod Brackets: VT-3. 30° Upper Surveillance Specimen Brackets: VT-3.
30° Lower Surveillance Specimen Brackets: EVT-1. All Steam Dryer Support Brackets: EVT-1. No Indications.
Spring 2009 EVT-1, VT-1,
& VT-3 Inspected two Jet Pump RB-1 locations, two Core Spray PB locations, eight FW Sparger End Bracket Attachment Welds, and Upper & Lower Surveillance Specimen at 300° location. No indications.
Spring 2011 EVT-1, VT-1,
& VT-3 Inspected one of three Surveillance Specimen Brackets at 120° location, and four Jet Pump Riser Brace (RB-1) locations. No recordable indications.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-16 Hatch Unit 2 Component Inspection Date Type Inspection Results RPV Interior Attachments Spring 2013 EVT-1 &
VT-3 Steam Dryer Hold Down Brackets: Inspected all four locations. No indications.
Steam Dryer Support Brackets: Inspected two locations. Repairs made 2R18 (2005).
No changes noted.
Spring 2015 EVT-1 &
VT-3 Core Spray Bracket and Attachment Welds to RPV at 330° location. No indications.
Spring 2017 EVT-1 &
VT-3 Performed re-examinations of: (1) the RPV Clad punch mark-like indication at 300°,
which was first identified and measured in depth in 2011 and assessed not to penetrate the clad, and (2) Steam Dryer Support Lug Attachment Weld to RPV at 326°. Found no changes in the previously identified indications.
Performed examinations of the: Upper Guide Rod Bracket Attachment Weld to the RPV (0° & 180°), Guide Rod and Lower Guide Rod Bracket Attachment Weld to the RPV (0° & 180°), Upper and Lower Surveillance Specimen Bracket Attachment Weld to the RPV (30°), Steam Dryer Support Lug Attachment Weld to the RPV (34° & 326°), and the Core Spray Piping Bracket to the RPV (30° & 210°). Minor service related indications were found at the Upper Guide Rod and were evaluated as acceptable for continued operation. No other recordable indications.
Additionally, the Surveillance Specimen at 120° was removed.
Steam Dryer Spring 2007 VT-1 BWRVIP-139 2 - Steam Dryer Cover Plate Horizontal Welds at 0° & 180° - No indications 2 - Steam Dryer Upper Hood Horizontal Welds - No indications 2 - Steam Dryer Radial Cover Plate Welds at 90° & 270° - No indications 8 - Steam Dryer Drain Channel Welds - No indications 1 - Steam Dryer Manway Cover Weld at 270 degrees - No indications 49 - Steam Dryer Vertical End Plate & Partition Welds - No indications.
28 - Steam Dryer Tie Bars & Welds - No indications.
1 - Steam Dryer Upper Support Ring 0-360° (Top & Vert Surfaces) Minor indications on upper support ring side are monitored for change.
4 - Steam Dryer Lifting Eye and Attachment Welds. No indications.
Asset Management 4 - Steam Dryer Seismic Brackets - Minor indications on upper support ring side are monitored for change with no discernable changes.
Enclosure to NL-18-1480 SNC Response to NRC Request for Additional Information E-17 Hatch Unit 2 Component Inspection Date Type Inspection Results Steam Dryer 2 - Steam Dryer Lower Support Ring (24 either side of guides at 0° & 180°) - No indications.
1 - Steam dryer Upper Guide at 180° - No indications.
Spring 2009 VT-1 (89)
Inspected all four steam dryer seismic brackets and upper support ring top and vertical surfaces 0-360° - Minor indications on upper support ring side were being tracked for changes. No discernable changes.
Spring 2011 VT-1 (89)
Inspected steam dryer upper support ring top and vertical surfaces (0-360°). Minor indications on upper support ring side were being tracked for changes. No discernable changes.
Spring 2013 VT-1 (89)
Inspected four steam dryer lifting eye, rod, & attachment welds, two steam dryer seismic brackets & attachment welds to support ring, one manway cover weld and three other horizontal hood welds, the lower support ring and upper and lower guides at 0 deg, 9 vertical partition welds, 12 vertical hood welds, 4 drain channels, and 14 tie bars. Damage due to steam dryer removal or installation at 0 deg upper guide was evaluated acceptable as-is. No other recordable indications.
Spring 2015 VT-1 (89)
Inspected steam dryer upper and lower guides at 180°. No indications.
Reinspected steam dyer seismic brackets at 214° and 146°. No changes to existing indications.
Minor changes to wear pattern on contact surfaces of at both locations. Evaluated as acceptable.
Spring 2017 VT-1 (89)
Performed examinations on the Upper Support Ring Vertical and Top Surfaces (from 0°-360°). There were no changes to existing indications.
Performed examinations on the Steam Dryer: Lifting Eyes (two), Rod and Attachment Welds (two each), Tie Bar and Attachment Welds (14 each), Vertical Hood Welds (ten), Vertical Hood Support Welds (eight), Vertical Partition Welds (seven), Drain Channel Welds (one - DC-8), Horizontal Welds (three), and the Lower Support Ring (180°). No recordable indications.