ML12053A408
ML12053A408 | |
Person / Time | |
---|---|
Site: | North Anna ![]() |
Issue date: | 09/15/2011 |
From: | Meena Khanna Division of Operating Reactor Licensing |
To: | Patrick Boyle, Karwoski K, Martin R Division of Engineering, Division of Operating Reactor Licensing |
References | |
FOIA/PA-2011-0357 | |
Download: ML12053A408 (10) | |
Text
Martin, Robert
§Sr From: Khanna, Meena a/ ..
Sent: Thursday, Septemlr 15, 2011 9:29 PM To: Karwoski, Kenneth; Martin, Robert; Boyle, Patrick
Subject:
North Anna Seismic Issue Restart Action Plan draft final.docx Attachments: North Anna Seismic Issue Restart Action Plan draft final.docx Here is the latest action plan..it's still a draft..thanks 1
MEMORANDUM TO: Eric J. Leeds, Director Office of Nuclear Reactor Regulation FROM: Joseph Giitter, Director Division of Engineering
SUBJECT:
ACTION PLAN TO ADDRESS NORTH ANNA NUCLEAR POWER PLANT RESTART AS A RESULT OF AUGUST 23, 2011 EARTHQUAKE On August 23, 2011, the North Anna Power Station declared an Alert due to significant seismic activity onsite from an earthquake which had a measured magnitude of 5.8. On August 26, 2011, initial reviews of the data determined that the seismic activity potentially exceeded the Design Basis Earthquake magnitude value. Subsequently on August 26, the licensee declared all safety-related structures, systems and components inoperable and issued a 10 CFR 50.72 Notification.
In response to the recent seismic event, the staff is undertaking various initiatives. Region I1 dispatched an Augmented Inspection Team on August 29, 2011, to capture the performance of the plant due to the earthquake to address plant restart activities at the North Anna Nuclear Plant, which includes an Augmented Inspection Team that was dispatched on August 29, 2011.
In addition, the staff is in the process of identifying issues and questions for the licensee to address in order to obtain NRC authorization for plant restart in accordance with 10 CFR Part 100, Appendix A. The attached agency's action plan describes and tracks the ongoing initiatives related to the North Anna Nuclear Power Plant restart activities as a result of the recent seismic event.
This plan was coordinated through the NRR Leadership Team.
Enclosure:
As stated CONTACT: Meena Khanna, NRR/DORL (301) 415-2150
MEMORANDUM TO: Eric J. Leeds, Director Office of Nuclear Reactor Regulation FROM: Joseph Giitter, Director Division of Engineering
SUBJECT:
ACTION PLAN TO ADDRESS NORTH ANNA NUCLEAR POWER PLANT RESTART AS A RESULT OF AUGUST 23, 2011 EARTHQUAKE On August 23, 2011, the North Anna Power Station declared an Alert due to significant seismic activity onsite from an earthquake which had a measured magnitude of 5.8. On August 26, 2011, initial reviews of the data determined that the seismic activity potentially exceeded the Design Basis Earthquake magnitude value. Subsequently on August 26, the licensee declared all safety-related structures, systems and components inoperable and issued a 10 CFR 50.72 Notification.
In response to the recent seismic event, the staff is undertaking various initiatives. Region II dispatched an Augmented Inspection Team on August 29, 2011, to capture the performance of the plant due to the earthquake to address plant restart activities at the North Anna Nuclear Plant, which includes an Augmented Inspection Team that was dispatched on August 29, 2011.
In addition, the staff is in the process of identifying issues and questions for the licensee to address in order to obtain NRC authorization for plant restart in accordance with 10 CFR Part 100, Appendix A. The attached agency's action plan describes and tracks the ongoing initiatives related to the North Anna Nuclear Power Plant restart activities as a result of the recent seismic event.
This plan was coordinated through the NRR Leadership Team.
Enclosure:
As stated CONTACT: Meena Khanna, NRR/DORL (301) 415-2150 ML No:
OFFICE INRL:N ODEi R DO:N NAME MKhanna KKarwoski RMartin WRuland MEvans BHolian 9/ /2011 9/ /2011 9/ /2011 9/ /2011 9/ /2011 9/ /2011 DATE OFFICE DIRS:NRR Region 11 DE:NRR OGC NRR NAME MCheok LWert PHiland JGiitter CScott ELeeds 9/ /2011 9/ /2011 9/ /2011 9/ /2011 9/ /2011 9/ /2011 DATE
NORTH ANNA NUCLEAR POWER PLANT RESTART ACTION PLAN Last Update: 9/15/2011 Lead Division: DORL Supporting Divisions: DE, DSS, DCI, DLR, DIRS, and DRA Supporting Offices: Region II, NMSS, NRO, RES, and OGC TAC Nos. ME7050 and ME7051 GOAL The goal of this action plan is to identify and coordinate the agency's ongoing initiatives related to the North Anna Nuclear Power Plant (NANPP) restart decision as a result of the recent seismic event on August 23, 2011.
BACKGROUND On August 23, 2011, NANPP experienced a seismic activity event (5.8 magnitude earthquake reported by the U.S. Geological Survey) which resulted in a loss of offsite power and automatic reactor trip of both units. The licensee declared an Alert due to significant seismic activity on the site. Subsequent to the earthquake, the licensee stabilized both units, restored offsite power, and sent the retrieved recorded seismic results to the vendor for analysis. On August 26, 2011, initial reviews of the data determined that the seismic activity potentially exceeded the Safe Shutdown Earthquake magnitude (SSE) value above 5 Hz. Therefore, this event was reportable per 10 CFR 50.72(b)(3)(ii) (B) for the nuclear power plant being in an unanalyzed condition that significantly degrades plant safety.
NANPP has two SSE ground motions, one for structures, systems, and components (SSCs) located on top of rock, which is anchored at 0.12 g, and the other is for SSCs located on top of soil, which is anchored at 0.18 g. The NANPP has two corresponding Operating Basis Earthquake (OBE) ground motion spectra, anchored at 0.09 g for soil and 0.06 g for rock. The vendor has processed the initial seismic data. Preliminary results indicate certain measurements have exceeded the SSE, at various frequencies above the limits reported in the final safety analysis report.
The current best estimate of the Peak Ground Acceleration (PGA) for the NANPP site is 0.26 g, which contains uncertainty. This estimate indicates that the ground motion likely exceeded the SSE response spectra for NANPP Units 1 and 2 (0.12 g) over a considerable frequency range.
This preliminary estimate appears to validate the NRC's current seismic hazard assessment approaches and the basis for GI-199 reviews.
Currently, North Anna Units 1 and 2 are in Cold Shutdown with the Residual Heat Removal System providing core cooling. The licensee planned on commencing the refueling outage for North Anna Unit 2 during the week of September 12, 2011. No significant equipment damage to Safety Related system (including Class I Structures) has been identified through site walk-downs nor has equipment degradation been detected through plant performance and surveillance testing following the earthquake. Therefore, there is reasonable assurance that the Safety Related systems are fully functional. The licensee indicated that the Spent Fuel Pit cooling system also remains fully functional and the temperature of the Spent Fuel Pit remained unchanged during the event. The licensee also indicated that the vendor will complete the
analysis of the seismic data and this information will be utilized to address the long term actions following the earthquake.
It is also noted that the North Anna Independent Spent Fuel Storage Installation (ISFSI) suffered minor damage from the earthquake. Twenty five of the twenty seven TN-32 casks moved up to 4.5 inches on the concrete pad during the quake. Six cask sets (12 casks) were closer than the 16 foot separation distance specified in the FSAR. There was no damage to the pressure monitors in each cask and no pressure monitoring system alarms during or after the earthquake. There were no crack indications observed in the concrete pad or casks for the TN-32 casks. For the TN-NUHOMS modules, some slight damage was identified around the outlet vents and some limited spalling occurred. Additionally, some modules showed gaps between them of approximately 1.5" versus the required 1.0" maximum gap.
The NRC initially dispatched a seismic and structural expert to assist the Agency's resident inspectors on site. The NRC then dispatched an Augmented Inspection Team on August 29, to assess the circumstances surrounding the total loss of offsite power and dual unit reactor trip, 2H emergency diesel generator coolant leak and other plant equipment issues following the seismic event on August 23, 2011, at the North Anna Power Station.
REGULATORY OUTCOME In accordance with Appendix A to Part 100, Paragraph V(a)(2), a nuclear power plant is required to be shutdown when the vibratory ground motion exceeds that of the Operating Basis Earthquake. In addition, the regulations state that "prior to resuming operations, the licensee '
will be required to demonstrate to the Commission that no functional damage occurred to those features necessary for continued operation without undue risk to the health and safety of the public." It is also noted that the NANPP UFSAR Section 3.7.4.6 has similar words and commits to demonstrate to the NRC that no functional damage has occurred to those features necessary for continued operation without undue risk to the health and safety of the public.
Licensee actions are underway to inspect, evaluate, test, and repair if necessary, the systems and components to ensure they are capable of performing their required functions. The licensee is performing plant walk downs in accordance with RG 1.167, "Restart of a Nuclear Power Plant Shutdown by a Seismic Event," which endorses EPRI's "Guidelines for Nuclear Plant Response to an Earthquake" with conditions. The staff notes that the EPRI guidelines do not address earthquakes beyond DBE, therefore additional inspections will be required beyond these guidelines.
The staff's assessment will utilize the guidance provided in NRC's Regulatory Guide (RG) 1.167, which endorses the EPRI's guidelines. In addition, the staff will utilize the IAEA Safety Report Series No. 66, "Earthquake Preparedness and Response for Nuclear Power Plants," to determine the adequacy of the licensee's restart determinations. It should be noted that the IAEA Safety Report acknowledges the prospect that hidden damage (especially after an SSE) is a possibility and its effects should be evaluated with analytical work. Specific actions are identified in the table below, entitled, "North Anna Nuclear Power Plant Restart Action Plan Milestones."
The initial acceptance criteria that will be utilized by the staff for approval of plant restart include satisfactorily addressing the following:
(1) Confirmatory inspections by the region, (2) Visual walkdowns by the licensee in accordance with the EPRI guidelines, (3) Identification of short term evaluations by licensee (pre-restart), and (4) Identification of long term evaluations by licensee (post-restart).
Project Management Structure:
This project is being performed as a matrix organizational structure. Team members will support project activities directly but will report administratively through their normal management chain. Approvals will be achieved through the standard concurrence process.
Responsible Division Director: Joseph Guitter, DORL Responsible Individuals: Meena Khanna (DORL), Kenneth Karwoski (DCI), and Robert Martin and Patrick Boyle (DORL)
Other stakeholders and roles:
DD DE: Patrick Hiland, George Wilson, and Kamal Manoly DD DSS: Bill Ruland DD DCI: Michele Evans DD DRA: Michael Cheok DD DLR: Brian Holian DD NMSS/SFST: Vonna Ordaz DDD NRO/DSER: Nilesh Chokshi DD, NRO/DE: T. Bergman OPA: S. Burnell, Manage External Communications OCA: E. Dacus, Congressional Liaison Regions: R. Conte, RI; M. Franke and Gerald McCoy, RII; D. Hills, RIII; G. Werner, RIV I DPR: A. Russell, Action Plan Structure, Action Plan website updates Project Attributes:
The project will consist of six broad phases, as addressed below.
The first phase involves a preliminary collection of issues that the staff expects the licensee to address, in a systematic approach (i.e., sections of the North Anna Updated Final Safety Analysis Report) in the short term and long term. Objectives during this phase include assembling a catalogue of questions to request of the licensee to address in either inspection or licensing.
The second phase includes inspection and assessment of the licensee's walkdowns and activities, via the Augmented Inspection Team.
The third phase involves reviewing the licensees restart document and identifying short term issues that the licensee must demonstrate prior to restart.
The fourth phase involves reviewing the licensee's restart document and identifying long term issues that the licensee must demonstrate post plant restart. These items may involve issuing requests for additional information, conducting a series of public meetings and conference calls, development of a temporary inspection instruction, and perhaps some audits.
The fifth phase addresses the development of a regulatory vehicle to ensure that the licensee adequately addresses the new design basis earthquake in its Updated Final Safety Analysis Report, as appropriate.
The sixth phase includes the development of regulatory products, which includes potentially issuing an Order, generic communications, and developing communications tools such as briefing sheets, etc., as appropriate.
Project Success Criteria Include:
The NRC staff will conduct an effective, independent review of the licensee's analysis and recovery actions to ensure that the licensee adequately implements the RG 1.167 and EPRI guidelines, as well as the initiative activities in accordance with the IAEA Safety Report No. 66, to effectively address short and long-term plant restart issues. The staff will conduct a systematic review, using the North Anna UFSAR, and conduct audits and confirmatory walkdowns/inspections, as appropriate. Stakeholders are informed of and educated about the safety significance of this issue.
The milestones in the action plan, and documents or products that result from completed milestones should be publicly available. Planning information, personnel assignments and draft documents will not, in general, be made public.
Current Status: As noted in table Potential Problems: N/A Closeout Criteria: N/A Proposed Resources and Re-prioritization: Approximately 1.5 FTE is expected to be expended to address this issue. Re-prioritization may be required to support plant restart activities. At this time, no contract costs are expected to be required.
Contacts:
DORL: A. Howe, M.Khanna, R. Martin, P. Boyle DE: G. Wilson, R. Matthew, M. Khanna DCI: K. Karwoski, T. McMurtray, T. Lupold, M. Mitchell, and M. Murphy DSS: G.Casto, R. Dennig, A. Ulses, A. Mendiola DLR: B. Pham, R. Auluck, and D. Pelton DIRS: T. Tate and D. Harrison NRO: C. Munson, R. Karas, N. Chokshi NMSS: E. Love and E. Benner RES: R. Hogan OPA: S. Burnell OCA: E. Dicus Region I: R. Conte Region I1: M. Franke and G. McCoy Region II: A. Shaihk Region IV: G. Werner
References:
10 CFR Part 100, Appendix A, Seismic and Geologic Siting for Nuclear Power Plants RG 1.167, "Restart of a Nuclear Power Plant Shut Down By a Seismic Event" EPRI NP-6695 Guideline, "Guidelines for Nuclear Power Plant Response to an Earthquake" IAEA Safety Report No. 66, "Earthquake Preparedness and Response for Nuclear Power Plants" Augmented Inspection Charter to Evaluate Total Loss of Offsite Power, Dual Unit Reactor Trips and Plant Equipment Issues Following a Seismic Event at North Anna Dominion Presentation Slides, September 8, 2011 (ADAMS Accession No. ML11252A006)
NORTH ANNA NUCLEAR POWER PLANT RESTART ACTION PLAN MILESTONES Item# Milestone Completion Lead Date Applicable technical branches within DE, DSS, DCI, DE DIRS, and DLR to identify questions and issues that the licensee should address for restart. This includes short term (prior to restart) and long term initiatives (post restart).
2 As issues are identified and finalized, weekly Ongoing DORL conference calls/meetings will be held with the licensee to address short and long term actions.
3 Short term and long term actions and issues shall be DORL identified and documented for issuance to the licensee via DORL.
4 Questions and issues will be categorized in one of the DORL/DE following: (a) confirmatory inspections by the region, (b) items to be confirmed via licensee's visual inspection/walkdowns, (c) short term evaluations by licensee (pre-restart), and (d) long term evaluations by licensee (post-restart).
5 Address any safety related concerns associated with NMSS the movement of the ISFSIs as a result of the earthquake, via questions and inspections.
6 Upon Augmented Inspection Team exit, any follow-up REGION II issues/actions will be communicated and addressed by staff as appropriate. Region to seek assistance via appropriate vehicle to address outstanding issues.
7 Develop a team to address path forward in reviewing DORL licensee's submittal for plans to restart.
o Develop the language for an Order, to define the DORL/DE licensee's actions needed to restart.
9 Upon receipt of licensee's formal request for restart DORL submittal, team to assess results of their inspections and readiness reviews, with support from technical branches, as appropriate. This will include developing questions and final input to NRC restart document.
10 Assess root cause for diesel generator failure and REGION II include input in staff's document for restart. Any other issues shall be addressed similarly.
Item# Milestone Completion Lead Date 11 Conduct inspections at site to verify any outstanding REGION II issues.
12 Develop template for NRC Restart Document and DORL incorporate input from OGC, etc., as appropriate.
13 Conduct Public Meeting prior to issuance of NRC DORL Restart Document.
14 Issue NRC Restart Document. DORL 15 As necessary, determine the need for appropriate DORL/OGC/OE regulatory vehicle for long term issues, i.e., revisions to FSAR to address new DBE.
16 Address any potential generic issues, e.g., seismic Region II instrumentation power supplies, seismic monitor NMSS/DE/DPR locations on structures as well as in the "free field," and seismic monitors on ISFSI pads.
17 Continue to respond to routine communications Ongoing DE between the resident inspectors and local officials based on public interest. See DE Communication Plan (ADAMS ML #).
18 Address Issues for Resolution, as applicable DE/DIRS 19 Conduct Commissioner TA Briefings Ongoing DORL 20 Conduct ACRS Briefings DORL and Technical Branches