IR 07200028/2014002
| ML15175A212 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 06/24/2015 |
| From: | Marc Ferdas Division of Nuclear Materials Safety I |
| To: | Rausch T Susquehanna |
| References | |
| IR 2014002 | |
| Download: ML15175A212 (9) | |
Text
June 24, 2015
SUBJECT:
NRC INDEPENDENT SPENT FUEL STORAGE INSTALLATION INSPECTION REPORT NO. 07200028/2014002, SUSQUEHANNA NUCLEAR, LLC, BERWICK, PENNSYLVANIA
Dear Mr. Rausch:
This refers to the Independent Spent Fuel Storage Installation (ISFSI) reactive inspection conducted between December 2, 2014, and June 15, 2015, at Susquehanna Nuclear, LLCs Susquehanna Steam Electric Station (SSES) Unit 2. The purpose of the inspection was to follow-up on the identification of indications of the siphon/vent block base metal on dry storage canister (DSC) #83. The results of this inspection were discussed with Duane Karchner and other members of your staff at the conclusion of the inspection on June 15, 2015, and are described in the enclosed report. No findings of safety significance were identified.
In accordance with 10 Code of Federal Regulations (CFR) 2.390 of the NRC's "Rules of Practice," a copy of this letter and its enclosure, and your response (if any) will be made available electronically for public inspection in the NRC Public Document Room or from the NRC document system (ADAMS), accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html. To the extent possible, your response should not include any personal privacy, proprietary, or safeguards information so that it can be made available to the Public without redaction.
Current NRC regulations and guidance are included on the NRC's website at www.nrc.gov; select Radioactive Waste; Storage of Spent Nuclear Fuel; then Regulations, Guidance and Communications. The current Enforcement Policy is included on the NRC's website at www.nrc.gov; select About NRC, Organizations & Functions; Office of Enforcement; Enforcement documents; then Enforcement Policy (Under 'Related Information'). You may also obtain these documents by contacting the Government Printing Office (GPO) toll-free at 1-866-512-1800. The GPO is open from 8:00 a.m. to 5:30 p.m. EST, Monday through Friday (except Federal holidays).
UNITED STATES NUCLEAR REGULATORY COMMISSION
REGION I
2100 RENAISSANCE BOULEVARD, SUITE 100 KING OF PRUSSIA, PA 19406-2713 No reply to this letter is required. Please contact Steve Hammann at 610-337-5399 if you have any questions regarding this matter.
Sincerely,
/RA MRoberts f/
Marc S. Ferdas, Chief Decommissioning and Technical Support Branch Division of Nuclear Materials Safety
Enclosure:
NRC Inspection Report No.
07200028/2014002
cc w/encl:
Distribution via ListServ
EXECUTIVE SUMMARY
NRC Inspection Report No. 07200028/2014002
The inspectors reviewed SSESs activities associated with the repair of dry shielded canister (DSC) #83 after the identification of indications on the siphon/vent block base metal. The condition was documented in SSESs corrective action program in Condition Reports (CRs)2014-36107, 37018, and 37033. The inspectors interviewed SSES and Transnuclear, Inc. (TN)personnel, reviewed SSES and TN documents and procedures, and observed repairs to the DSC between December 2-5, 2014. The inspection continued through June 15, 2015, and consisted of in-office reviews of information provided by SSES. The inspectors also reviewed SSESs corrective actions and apparent cause investigation report.
Based on the results of this inspection, no findings of safety significance were identified.
REPORT DETAILS
1.0 Background
On November 19, 2014, during the performance of nondestructive examination (NDE)dye penetrate testing (PT) on DSC #83, multiple indications (areas of potential imperfections in the base metal) were found in the heat-affected zone area around the siphon/vent block port cover welds. The NDE was performed after the completion of welding of the siphon/vent block port covers. In consultation with the dry cask vendor and CoC holder, TN, it was determined that the siphon/vent block should be repaired by grinding out the base metal indications. Upon completion of the repair work and successful completion of a PT on the vent and siphon port welds, the outer top cover (OTC) was installed and a helium leak rate test was re-performed on November 21, 2014, as required by the Technical Specifications (TS) for the CoC. The helium leak rate test did not pass the requirements specified in TS 1.2.4a. The test was repeated several times between November 21-22, 2014, and on each occasion did not meet the TS requirement. All activities associated with the processing of the DSC were placed on hold while SSES and TN developed a repair plan for DSC #83. Prior to implementing the repair plan, TN demonstrated to SSES, at their facility in Aiken, South Carolina, that they could remove the OTC by grinding out the welds without damaging the DSC. On December 2, 2014, SSES approved the final version of the repair plan, PTIP-30696-5.2, Rev.0, Susquehanna Weld Remediation, and repair activities commenced the same day.
2.0 Scope
a. Inspection Scope
(Inspection Procedures (IPs) 60855 and 60855.1
The inspectors reviewed SSESs activities associated with the repair of DSC #83 after the identification of indications on the siphon/vent block base metal. The condition was documented in SSESs corrective action program in CRs 2014-36107, 37018, and 37033. The inspectors interviewed SSES and TN personnel, reviewed SSES and TN documents and procedures, and observed repairs to the DSC between December 2-5, 2014. The inspection continued through June 15, 2015, and consisted of in-office reviews of information provided by SSES. The inspectors also reviewed SSESs corrective actions and apparent cause investigation report.
b. Observations and Findings
The inspectors reviewed the results of PT and ultrasonic testing (UT) of the edges of the DSC after the OTC was removed, and verified that the DSC was not damaged by the grinding out of the OTC welds. After the completion of localized helium leak rate testing, SSES determined the siphon/vent block was the source of the leakage. The inspectors observed the performance of a weld overlay of the entire top of the siphon/vent block up to within 3/16 of the edge of the siphon/vent block. A PT of the weld overlay showed additional indications on the siphon/vent block in the 3/16 edge that did not have the weld overlay. The inspectors reviewed the SSES and TN revised repair plan that placed a weld overlay on the portion of the siphon/vent block that had not previously had an overlay. Further localized helium leak rate testing did not indicate any further leaks after the completion of the weld overlays and SSES re-entered their procedure for processing of DSC #83. On December 12, 2014, processing of DSC #83 was completed and the inspectors confirmed that the DSC met all the TS requirements prior to it being moved to the ISFSI pad on December 16, 2014. The inspectors verified that throughout the repair the DSC was in a safe stable condition and all TS requirements were met.
The inspectors reviewed the root cause investigation report that documented the determination that the siphon/vent block had been fabricated from a thick rolled plate and contained inherent inclusions resulting during ingot solidification. The inclusions induced in the rolled plate were brought to the block face by weld-induced stresses. The inspectors confirmed that SSES has two unused canisters on-site that had their siphon/vent blocks fabricated from the same lot of rolled plate as DSC #83. Planned corrective actions include placing a weld overlay on the siphon/vent block of one of the unused canisters and returning the other canister to the manufacturer. These activities are being tracked in the corrective action program.
c. Conclusions
Based on the results of this inspection, no findings of safety significance were identified.
3.0
Exit Meeting Summary
On June 15, 2015, the inspectors presented the inspection results, via teleconference,
to Duane Karchner, Refuel Floor Manager, and other members of SSESs staff.
PARTIAL LIST OF PERSONS CONTACTED
Susquehanna
- Duane Karchner, Refuel Floor Manager
- Justion Mirilovich, Refuel Floor Shift Manager
- Anthony Nestico, Refuel Floor Shift Manager Brenda ORourke, Senior Engineer Robert Rose, Engineering Robert Specht, NDE Transnuclear Mike Williams, Director of Operations Pam Waite, Work Package Coordinator David Wright, Project Coordinator
- Indicates attendance at the exit meeting
ITEMS OPEN, CLOSED, AND DISCUSSED
None
LIST OF
DOCUMENTS REVIEWED
Analysis and Tests
AREVA Examination Summary Sheet, Ultrasonic Exam, SSE-61BTH-1-B-2-050, SSE-61BTH-1-
B-2-051
AREVA Root Cause Investigation of Siphon and Vent Block Base Metal Indications (AREVA TN
Root Cause Investigation 2014-339)
Helium Leak Rate Test, Inner Lid to Shell, Port Cover Plate & outer Top Cover, Canister 81
Helium Leak Rate Test, Vent and Siphon Port Cover Plates, Canister 81
Helium Leak Rate Test, Inner Lid to Shell, Port Cover Plate & outer Top Cover, Canister 82
Helium Leak Rate Test, Vent and Siphon Port Cover Plates, Canister 82
Liquid Penetrant Examination, Final Pass Welds for Inner Vent & Siphon Port Covers,
Canister 83
Liquid Penetrant Examination, Rework of Indication Areas at Vent & Siphon Port Covers,
Canister 81
Liquid Penetrant Examination, Root Pass Weld for Inner Top Cover Plate, Canister 81
Liquid Penetrant Examination, Root Pass Weld for Inner Top Cover Plate, Canister 82
Liquid Penetrant Examination, Top surface of Block, Cannister S/N-SSE-61BTH-1-2-050
Condition Reports
CR 2014-35887, 2014-36107, 2014-37018, 2014-37033, 2014-37036
Transnuclear Nonconformance Report No: 2014-313, Rev. 0
Procedures
NDE-LT-001, Rev. 2, Helium Mass Spectrometer Leak Test Procedure for Dry Fuel Storage
Casks
NDE-PT-001, Rev. 4, Color Contrast Liquid Penetrant Examination
NDE-PT-003, Rev. 2, Color Contrast Liquid Penetrant Examination High Temperature
NDE-UT-014, Rev. 7, Ultrasonic Examination
PTIP-30696-5.2, Rev. 0, Rev. 0, Susquehanna Weld Remediation
PTIP-30696-5.2, Rev. 0, Rev. 1, Susquehanna Weld Remediation Procedure
Miscellaneous
2014 Dry Fuel Storage, Status Report - Campaign No. 8
2.48 Screening, Susquehanna Weld Remediation of DFS Canister
AREVA E-41005, Executive Summary of PPL and TN Review of Fabrication Issues
AREVA E-42068, DSC Procurement Specification, May 22, 2015
AREVA TN Form 15.1-1, Rev. 10, Reportability Determination, CAR No. 2014-339
AREVA Presentation SSE-61BTH-1-2-052 Repair Plan
Certificate of Compliance No. 1004, Amendment 10
Form 3.5-1, Rev.8 10 CFR Part 72.48 Applicability and 10 CFR Part 71 Review, LR No.
21004-1388 Rev. 1
PPL Susquehanna Pool to Pad 30969 TN Logbook 2014
Radiation Work Permit 2014-0204, Repair Dry Fuel Storage Canister #83
TC/DSC Monitoring Log
WPS TN-P8-P8-GT1, Rev. 1
WPS TN-P8-P8-GT2, Rev. 1
LIST OF ACRONYMS USED
Certificate of Compliance
Division of Nuclear Material Safety
Dry Shielded Canister
IP
Inspection Procedure
Independent Spent Fuel Storage Installation
NRC
Nuclear Regulatory Commission
OTC
Outer Top Cover
Dye Penetrant Test
Susquehanna Steam Electric Station
TN
Transnuclear, Inc.
TS
Technical Specifications
Ultrasonic Testing