IR 05000338/2012009
| ML12062A012 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 03/02/2012 |
| From: | Vias S J NRC/RGN-II/DRS/EB3 |
| To: | Heacock D A Virginia Electric & Power Co (VEPCO) |
| Linda Gruhler 404-997-4614 | |
| References | |
| IR-12-001, IR-12-009 | |
| Download: ML12062A012 (11) | |
Text
March 2, 2012
Mr. David President and Chief Nuclear Officer Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060
SUBJECT: NORTH ANNA POWER STATION - NRC ISFSI INSPECTION AFTER SEISMIC EVENT REPORTS 05000338/2012009, 05000339/2012009, 07200016/2012001 and 07200056/2012001
Dear Mr. Heacock:
On January 19, 2012, the U. S. Nuclear Regulatory Commission (NRC) completed an inspection of the Independent Spent Fuel Storage Installation (ISFSI) at your North Anna Power Station Units 1 and 2. The enclosed report documents the results of the inspection which were discussed on January 19, 2011, with Mr. Michael Crist and other members of your staff.
The inspection examined activities conducted under your licenses as they related to safety and compliance with the Commission's rules and regulations, and with the conditions of your licenses with respect to the ISFSI and related post-seismic recovery actions. The inspectors visually examined the condition of the ISFSI, reviewed selected procedures and records, observed activities at the ISFSI, and interviewed personnel with respect to the seismic event of August 23, 2011. This inspection was conducted to assess and verify, by direct observation of selected activities and independent evaluations, that licensee activities underway to inspect, evaluate, and repair if necessary, the ISFSI dry cask storage systems and components are adequate to ensure that those systems are capable of performing their required functions. Specifically, the inspection assessed the extent of the impact and damage to the ISFSI from the seismic event; verified that outstanding issues, including the acceptability of any repairs made to damaged ISFSI horizontal storage modules (HSMs), were being addressed; assessed the adequacy of licensee corrective actions with respect to the ISFSI; and identified long-term issues that the licensee must resolve prior to the next ISFSI loading campaign. Based on the results of this inspection, no findings were identified. The team concluded that your staff adequately inspected the plant's ISFSI, including associated structures, systems, and components (SSCs), to ensure that any damage from the August 23, 2011, seismic event was identified and was being properly evaluated and corrected prior to initiating the next fuel loading campaign. The inspectors did not identify any significant seismically induced damage. The inspectors also noted that these items had been entered into the corrective action or work control programs as required; that required root cause evaluations had been, or were being, 2 VEPCO conducted following the seismic event; and that the Action Plan established by your staff was adequate and would be completed prior to introducing additional spent fuel into the ISFSI. In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of the NRC's Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,/RA by Lou Lake Acting for/
Steven J. Vias, Chief Engineering Branch 3 Docket Nos. 50-338, 50-339, 72-16, 72-56 License Nos. NPF-4, NPF-7, SNM-2507, CoC-1004
Enclosure:
Inspection Reports 05000338/2012009, 05000339/2012009, 07200016/2012001, and 07200056/2012001 cc w/encl: (See Page 3)
2 VEPCO conducted following the seismic event; and that the Action Plan established by your staff was adequate and would be completed prior to introducing additional spent fuel into the ISFSI. In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of the NRC's Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,/RA by Lou Lake Acting for/
Steven J. Vias, Chief Engineering Branch 3 Docket Nos. 50-338, 50-339, 72-16, 72-56 License Nos. NPF-4, NPF-7, SNM-2507, CoC-1004
Enclosure:
Inspection Reports 05000338/2012009, 05000339/2012009, 07200016/2012001, and 07200056/2012001 cc w/encl: (See Page 3) Distribution w/encl: G. McCoy, RII DRP S. Ninh, RII, DRP C. Haney, Office Director, NMSS D. Weaver, Acting Director, NMSS/SFST M. Waters, Acting Deputy Director, NMSS/SFST C. Araguas, Acting Branch Chief, NMSS/SFST/RIOB R. Martin, Sr. Project Manager, NRR/DORL/LPL2-1 P. Hiland, Director, NRR/DE A. Howe, Deputy Director, NRR/DORL RIDSNRRDIRS PUBLIC RidsNrrPMNorthAnna Resource X PUBLICLY AVAILABLE G NON-PUBLICLY AVAILABLE G SENSITIVE X NON-SENSITIVE ADAMS: X Yes ACCESSION NUMBER: ML12062A012 __ X SUNSI REVIEW COMPLETE X FORM 665 ATTACHED OFFICE RII-DRS: EB-3 RII-DRS: EB-3 NMSS/SFST RII-DRP: Br 5 NMSS/SFST RII-DRS: EB-3 SIGNATURE /RA/ /RA/ /RA via email/ /RA/ /RA via email/ /RA L Lake for/ NAME R. Carrion C. Fletcher E. Love G. McCoy C. Araguas S. Vias DATE 3/ 1 /2012 3/ 1/2012 3/ 1 /2012 3/ 1 /2012 3/ 1 /2012 3/ 1 /2012 E-MAIL COPY YES NO YES NO YES NO YES NO YES NO YES NO OFFICIAL RECORD COPY DOCUMENT NAME: S:\DRS\ENG BRANCH 3\INSPECTIONS\INSPECTION AREAS\ISFSI\ISFSI INSPECTION REPORTS\NORTH ANNA ISFSI REPORT - FINAL (REV 1 MAR).DOC 3 cc w/encl: Mr. Gerald T. Bischof Site Vice President North Anna Power Station Virginia Electric & Power Company Electronic Mail Distribution Fred Mladen Director, Station Safety & Licensing Virginia Electric and Power Company Electronic Mail Distribution Michael Crist Plant Manager North Anna Power Station Virginia Electric & Power Company Electronic Mail Distribution Lillian M. Cuoco, Esq. Senior Counsel Dominion Resources Services, Inc. Electronic Mail Distribution Tom Huber Director, Nuclear Licensing & Operations Support Inssbrook Technical Center Electronic Mail Distribution Ginger L. Rutherford Virginia Electric and Power Company Electronic Mail Distribution Virginia State Corporation Commission Division of Energy Regulation P.O. Box 1197 Richmond, VA 23209 Attorney General Supreme Court Building 900 East Main Street Richmond, VA 23219 Senior Resident Inspector North Anna Power Station U.S. Nuclear Regulatory Commission P.O. Box 490 Mineral, VA 23117 Donald R. Taylor Licensing Supervisor North Anna Power Station P. O. Box 402 Mineral, VA 23117-0402 Michael M. Cline Director Virginia Department of Emergency Services Management Electronic Mail Distribution Executive Vice President Old Dominion Electric Cooperative Electronic Mail Distribution County Administrator Louisa County P.O. Box 160 Louisa, VA 23093 Enclosure U.S. NUCLEAR REGULATORY COMMISSION REGION II Docket Nos: 50-338, 50-339, 72-16, 72-56 TN-32 Dry Storage Cask (Docket No. 72-1021): Site-Specific License (Docket No. 72-16) NUHOMS HD Horizontal Modular Storage System (Docket No. 72-1030): General License (Docket No. 72-56)
License Nos: NPF-4, NPF-7, SNM-2507, CoC-1004 Report No: 05000338/2012009, 05000339/2012009, 07200016/2012001, and 07200056/2012001 Licensee: Virginia Electric and Power Company (VEPCO)
Facility: North Anna Power Station, Units 1 & 2 and the North Anna Independent Spent Fuel Storage Installation Location: 1022 Haley Drive Mineral, Virginia 23117 Dates: January 18 and 19, 2012 Inspectors: Robert Carrion, Senior Reactor Inspector, Region II Cecil Fletcher, Senior Reactor Inspector, Region II Earl Love, Safety Inspection Engineer, Office of Nuclear Materials Safety and Safeguards (NMSS) Approved by: Steven J. Vias, Chief, Engineering Branch 3
SUMMARY OF FINDINGS
05000338/2012009, 05000339/2012009, 07200016/2012001, and 07200056/2012001; 01/18/12 - 01/19/12; North Anna Power Station, Units 1 & 2; ISFSI inspection after seismic event.
This report covers on-site inspection and in-office review by regional and headquarters-based inspectors to evaluate the condition of dry cask storage of spent fuel after the seismic event of August 23, 2011. The inspectors concluded that your staff adequately inspected the independent spent fuel storage installation (ISFSI) and associated components to ensure that any damage from the August 23, 2011, seismic event was identified and was being properly evaluated and plans for correcting the identified damage prior to initiating the next fuel loading campaign were in place and were adequate. Based on the results of the ISFSI inspection activities, the NRC inspectors noted that no significant seismically induced damage was identified.
A. NRC Identified and Self-Revealing Findings
None
B. Licensee Identified Violations
None 3
REPORT DETAILS
Summary of Plant Status
North Anna Units 1 and 2 automatically shutdown during the seismic event of August 23, 2011, and remained in Mode 5, Cold Shutdown, until November 2011 to conduct extensive inspections to assure the safety of the reactors and associated systems. The units were then restarted.
OTHER ACTIVITIES
4OA3 Event Follow-up
1.0 Background 1.1 Plant in General On August 23, 2011, at 1:51 pm, with North Anna Power Station (NAPS) Units 1 and 2 operating at 100 percent power, a Magnitude 5.8 earthquake occurred approximately five miles from Mineral, Virginia. The epicenter was approximately 11 miles WSW of the NAPS. Based on an evaluation of the US Geological Survey (USGS) data and plant specific seismic data, the licensee has confirmed that the August 23, 2011, earthquake exceeded several spectral accelerations and the peak ground accelerations for the Operating Basis and Design Basis Earthquakes (OBE and DBE, respectively) for NAPS Units 1 and 2. This has also been confirmed by NRC seismologists that reviewed the data. On August 26, the licensee declared all safety-related structures, systems, and components (SSCs) inoperable and issued a 10 CFR 50.72 Event Notification. An Augmented Inspection Team (AIT) was dispatched by the NRC to the site following the seismic event. The majority of the AIT's activities focused on the plant and personnel response to the event and immediate actions taken by the licensee. (Refer to NRC Inspection Report 05000338/2011011, 05000339/2011011, 07200016/2011001, and 07200056/2011002; issued on October 31, 2011, Accession No. ML113040031.) To support the NRC's assessment of the readiness of the NAPS to return to service, a Restart Readiness Inspection Team was dispatched to the site to provide an evaluation of the plant condition, review the licensee's actions taken or planned to support restart, and assess the status of the corrective actions developed to address issues identified by the licensee and NRC inspection teams. The team concluded that the licensee adequately inspected plant SSCs to ensure that any damage from the August 23, 2011, seismic event was identified, properly evaluated, and corrected prior to initiating restart activities. (Refer to NRC Inspection Report 05000338/2011012, and 05000339/2011012, issued on November 30, 2011; Accession No. ML 113340345.) In addition, the NRC is undertaking several initiatives to establish agency actions in response to the earthquake that occurred near the NAPS to ensure that the ISFSI is acceptable for continued operation without undue risk to the health and safety of the public and to identify generic implications resulting from the review of this issue. The NRC has developed an action plan (Accession No. ML113290182) that describes and tracks the ongoing actions related to NAPS's ISFSI as a result of the seismic event.
1.2 ISFSI Specifics The North Anna ISFSI uses two spent fuel storage systems manufactured by Transnuclear, Inc. (TN) to store spent fuel. One system includes twenty-seven (27) vertical TN-32 metal casks licensed under a 10 CFR Part 72 site specific license. This system incorporates a bolted closure lid with a pressure monitoring/alarm system, and stands freely on the ISFSI concrete pad. The design/licensing basis for the TN-32 is controlled primarily by the North Anna ISFSI Final Safety Analysis Report (FSAR), NRC license (SNM-2507), and NRC Certificate of Compliance 1021. The ISFSI FSAR defines design acceleration values of 0.18g horizontal and 0.12g vertical, and horizontal displacement was not predicted to occur at these values. The second system includes twenty-six TN NUHOMS HD-32PTH horizontal storage modules (13 are currently loaded) under a 10 CFR Part 72 general license. This system uses a weld-sealed canister that rests on horizontal rails inside the horizontal storage module (HSM). The design/licensing basis for the TN NUHOMS HD-32PTH is controlled primarily by a separate TN NUHOMS-32PTH FSAR and NRC Certificate of Compliance 1030, as supplemented by additional site specific evaluations performed by North Anna personnel in accordance with 10 CFR 72.212. NUHOMS-HD-32PTH components are designed to withstand acceleration values of 0.30g horizontal and 0.20g vertical. Shortly after the seismic event, a licensee inspection of the ISFSI pads was conducted by the North Anna Fuel Handling team, Nuclear Analysis and Fuel personnel, and Transnuclear personnel following the guidance of Regulatory Guide (RG) 1.166, "Pre-Earthquake Planning and Immediate Nuclear Power Plant Operator Post-Earthquake Actions." The inspection noted that 25 of 27 TN-32 casks had moved slightly (a maximum of 4 1/2 inches) from their original placement locations and that the cask movement appeared to be independent of the slope of the pad. TN-32 casks with a total decay heat exceeding 27.1 kilowatts (kw) require a nominal 16-foot spacing. The inspections revealed that the center-to-center spacing between twelve casks was less than the 16-foot nominal value provided in ISFSI Technical Specification (TS) Section 4.2. However, all casks were determined to be below the 27.1-kw limit of the TN-32 cask SAR. For some of the TN NUHOMS-32PTH modules, slight damage was identified around the outlet vents and some surface cracking indications were noted. The surface cracking was considered to be minor because it met the criteria to be considered insignificant in accordance with the guidance of Electric Power Research Institute (EPRI) NP-6695, "Guidelines for Nuclear Plant Response to an Earthquake." In addition, some modules showed gaps between them of approximately 1.5 inches between adjacent vertical walls of the modules, as opposed to being "in contact with" adjacent modules, per FSAR Section 3.1.1 of the NUHOMS HD system. Therefore, the licensee determined that the damage observed (surface cracking, gaps, etc.) on the HSMs would not impact the structural load-carrying or radiation shielding capability of the HSMs. With the exception of two HSMs, damage to the HSM array was limited to unloaded HSMs. The spaces between some HSMs indicated that some minor movement had occurred resulting in a maximum gap of 1.5 inches at the roofline. Although the TN-32 casks had moved on the pad, they continued to meet their shielding, criticality, thermal, and confinement design functions. Also, for the NUHOMS HD-32PTH system, the total decay heat loads are significantly below their design limit of 34.8 kw, even though some of the HSMs sustained some minor, cosmetic damage, they continued to meet their shielding, criticality, thermal, and confinement design functions.
2.0 ISFSI Recovery Activities
a. Inspection Scope
(Inspection Procedure 60855) This inspection was conducted to assess and verify, by direct observation of selected activities and independent evaluations, that licensee activities underway to inspect, evaluate, and repair if necessary, the ISFSI dry cask storage systems and components are adequate to ensure that they are capable of performing their required functions. Specifically, the inspection assessed the extent of the impact and damage to the ISFSI from the seismic event; verified that outstanding issues, including the acceptability of any repairs made to damaged ISFSI HSMs, were being addressed; assessed the adequacy of licensee corrective actions with respect to the ISFSI; and identified long-term issues that the licensee must resolve prior to the next ISFSI loading campaign.
b. Observations and Findings
The inspectors assessed the immediate actions taken by the licensee to ensure that regulatory requirements were met and would continue to be met as the recovery progresses. The inspectors noted that the licensee followed RG 1.166, "Pre-Earthquake Planning and Immediate Nuclear Power Plant Operator Post-Earthquake Actions," and EPRI NP-6695 to perform post-event walkdowns and assessments of the ISFSI. The inspectors examined ISFSI Pad No. 2, the NUHOMS HD-32PTH HSM system, and noted the post-seismic event ISFSI conditions to be consistent with what was previously reported by the licensee (HSM gaps, minor damage to concrete roof vents and the module, rail alignment issues, etc). The inspectors noted that measurements of the gaps between HSM components have been provided to TN for evaluation of shielding design function as part of the licensee's seismic response action plan. The inspectors noted that alignment deviations had been identified by the licensee in both loaded and unloaded HSMs; the HSMs appeared to have moved relative to the ISFSI pad. Although these deviations do not impact the design functions of the facility, they may impact dry shielded canister (DSC) placement into and removal from the HSMs. The inspectors noted that the survey measurements were to be provided to TN for evaluation to determine potential detrimental effects on loading/retrieving a DSC from the HSM. The inspectors also reviewed survey rail alignment measurements for all unloaded HSMs for front-to-back and side-to-side rail elevations. The results revealed two rails, front-to-back centerline, of HSMs 14 and 19, were out-of-tolerance 9/64" and 1/16", respectively. The inspectors noted that all alignment deviations were being tracked for resolution on licensee's Corrective Action Program (CAP) Condition Reports (CRs) 458618, 458780, 458986, 459216, 459360, and that the measurements were to be provided to TN for evaluation. The inspectors noted that the licensee had completed seven (of 13) internal inspections of unloaded HSMs by direct visual inspection. The inspectors visually examined the inside of HSM No. 19 and noted no concrete cracking, spalling, or damage to the rails or rail extension flanges. The inspectors observed the removal of doors of three loaded HSMs (Nos.1, 3, and 13) and the licensee visual examination of each in accordance with Engineering Technical Evaluation 0189. Direct visual examination allowed the inspectors to observe the front opening of the HSM's base, which included the door seating ring, seismic restraint, and the extension flanges of the rails that were not obscured by the DSC. The inspectors observed no damage to the seismic restraints or rail extension flanges and no cracking or spalling of the HSM doors or HSM base door seating rings. The as-found condition and the inspection and ease of removal and replacement of each seismic restraint indicated that no movement of the DSCs had occurred during the seismic event. The inspectors observed the remote visual examination of the lower interior of loaded HSM Nos. 1, 3, and 13, and noted that the examination was performed using a remotely operated vehicle (ROV) with a camera. The inspectors observed that the use of the ROV camera was adequate to observe the underside of the HSM rails and the interior walls below the rails. The inspectors noted that the examination revealed no cracking or spalling of the HSM concrete or damage to the underside of the rails. The inspectors observed debris that did not appear to be of structural origin. The inspectors observed visual examination by the licensee of the upper interior of loaded HSM No. 12 below the roof and above the roof heat shields using a boroscope and noted that the use of a boroscope was adequate to observe the condition of the heat shield's attachment to the HSM roof as well the roof's underside. The inspectors noted that the examination identified no debris, cracking, or spalling of the HSM roof concrete, or detachment of the roof heat shields. The inspectors noted that the examination results for loaded HSMs Nos. 1, 3, and 12 on ISFSI Pad 2 were appropriately documented on CR 459532. The inspectors observed that the performance of licensee ISFSI activities and resolution of issues to date was on-going and that the licensee had taken a proactive approach to identify, document, and resolve ISFSI issues. Based on review of the licensee's CRs, corrective actions (CAs), and observations made during this inspection, the inspectors concurred with the licensee's conclusion that the ISFSI is acceptable for continued operation without undue risk to the health and safety of the public. The inspectors verified that the licensee's long-term action plan included rework/repair of concrete on the damaged HSMs; translation of seismic parameters to the ISFSIs from the plant's power block and analysis of the seismic event (using the resulting seismic acceleration response spectra) and analysis of both systems (on Pads 1 and 2); reassessment of the operability determination; resolution of generic issues such as seismic instrumentation and locations, pressure monitoring systems, and radiological surveys; and any long term issues, such as revisions to FSAR to address new DBE. The inspectors planned to assess the corrective actions and commitments outlined in the action plan on a continuous basis for regulatory compliance and completion prior to loading additional spent fuel into the ISFSI. 3.0 Exit Meeting Summary The inspectors presented the inspection results to Mr. Michael Crist, and other members of licensee management, on January 19, 2012. The licensee acknowledged the findings presented. The inspectors asked the licensee if any of the material examined during the inspection should be considered proprietary and the information that was identified as such was returned to the licensee prior to the inspectors' departure from the site.
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
- G. Bischof, Site Vice-President
- M. Crist, Plant Manager
- J. Guerci, Manager, Nuclear Fuels
- E. Hendrixson, Director, Site Engineering
- C. LaRoe, Supervisor, Nuclear Spent Fuel
- J. Leberstien, Regulatory Compliance
- R. Speckine, Supervisor, Fuel Operations
- D. Taylor, Supervisor, Licensing
LIST OF ITEMS
OPENED, CLOSED AND DISCUSSED
Opened
None
Closed
- None
Discussed
None
LIST OF DOCUMENTS REVIEWED
Condition Reports
(CRs)
- CR 458618, Alignment of Four HSMs
- CR 458780, Alignment of Nine HSMs at ISFSI Pad 2
- CR 458986, Alignment of Five HSMs at ISFSI Pad 2
- CR 459216, Alignment Checks of Unloaded HSMs at ISFSI Pad 2
- CR 459360, Inspection and Alignment Checks of Unloaded HSMs at ISFSI Pad 2
- CR 459532, Post-seismic Inspection results for Loaded HSMs at ISFSI Pad 2
Other Documents
- Engineering Technical Evaluation (ETE)
- NAF-2011-0188 ETE
- NAF-2011-0189 Work Order 59102410079, Remove Horizontal Spent Fuel Storage Module Doors for Engineering Seismic Inspections North Anna logs of 8/27/2011 at 16:50
- North Anna ISFSI - Response to August 23, 2011 Seismic Event -
- TN-32 & Pad 1 Action Plan North Anna ISFSI - Response to August 23, 2011 Seismic Event - NUHOMS & Pad 2 Action Plan Prompt Operability Determination OD000440, Independent Spent fuel Storage Installation Systems