ML11305A239

NRC Technical Audit Report of North Anna Post-Seismic Fuel Inspections

ML11305A239
Person / Time
Site:	North Anna
Issue date:	10/27/2011
From:	Huber T Dominion, Dominion Resources Services, Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
11-544D
Download: ML11305A239 (30)

Text

PROPRIETARY INFORMATION - WITHHOLD UNDER 10-q'l 2.390 Dominion Resources Services, Inc.

Innsbrook Technical Center-5000 Dominion Boulevard, 2SE, Glen Allen, VA 23060 V - om lniolon 10 CFR 100, Appendix A October 27, 2011 U.S. Nuclear Regulatory Commission Serial No.: 11-544D Attention: Document Control Desk NL&OS/ETS R1 Washington, DC 20555 Docket Nos.: 50-338/339 License Nos.: NPF-4/7 VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION)

NORTH ANNA POWER STATION UNITS 1 AND 2 NRC TECHNICAL AUDIT REPORT OF NORTH ANNA POST-SEISMIC FUEL INSPECTIONS - PROPRIETARY INFORMATION In a letter dated October 25, 2011, the NRC provided Dominion the technical audit report of the post-seismic fuel inspections and requested that Dominion and the fuel vendor, AREVA NP, Inc, review the report for proprietary information. Dominion and AREVA have reviewed the technical audit report and determined that the audit report does contain proprietary information. Therefore in Attachment 1, Dominion is providing a copy of the NRC's Technical Audit Report with the proprietary information identified and labeled in accordance with 10 CFR 2.390. Attachment 1 is supported by an AREVA Application for Withholding Proprietary Information for Public Disclosure and the accompanying Affidavit signed by AREVA, the owner of the information, and is provided in Attachment 3. The affidavit sets forth the basis on which the information may be withheld from public disclosure by the Commission and addresses with specificity the considerations listed in paragraph (b)(4) of 10 CFR 2.390 of the Commission's regulations.

Accordingly, it is respectfully requested that the information, which is proprietary to AREVA NP, be withheld from public disclosure in accordance with 10 CFR 2.390.

Correspondence with respect to the copyright or proprietary material in the "NRC Audit Report for North Anna Post-Seismic Fuel Inspections," in Attachment 1 of this letter or the supporting AREVA NP affidavit should be addressed to Ms. Gayle F. Elliott, Manager, Product Licensing, AREVA NP, Inc., 3315 Old Forest Road, P.O. Box 10935, Lynchburg, VA 24506-0935. A redacted (non-proprietary) version of Attachment 1 has been included as Attachment 2 for public disclosure.

ATTACHMENT 1 CONTAINS PROPRIETARY INFORMATION THAT IS BEING WITHHELD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390. UPON SEPARATION OF ATTACHMENT 1, THIS LETTER IS DECONTROLLED.

Awl

Serial Number 11-544D Docket Nos. 50-338/339 Page 2 of 3 If you have any questions or require additional information, please contact Mr. Thomas Shaub at (804) 273-2763.

Sincerely, T. R. Huber Director - Nuclear Licensing and Operations Support Dominion Resources Services Inc., for Virginia Electric and Power Company There are no commitments made in this letter.

Attachments

1. NRC Technical Audit Report of North Anna Post-Seismic Fuel Inspections - Proprietary

2. NRC Technical Audit Report of North Anna Post-Seismic Fuel Inspections - Non-Proprietary

3. Affidavit

Serial Number 11-544D Docket Nos. 50-338/339 Page 3 of 3 cc: Regional Administrator U.S. Nuclear Regulatory Commission - Region II Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, Georgia 30303-1257 NRC Senior Resident Inspector North Anna Power Station M. Khanna NRC Branch Chief- Mechanical and Civil Engineering U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 G-9E3 11555 Rockville Pike Rockville, MD 20852-2738 R. E. Martin NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 G-9A 11555 Rockville Pike Rockville, MD 20852-2738 P. G. Boyle NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 G-9A 11555 Rockville Pike Rockville, MD 20852-2738

Serial Number 11-544D Docket Nos. 50-338/339 Attachment 2 NON-PROPRIETARY NRC Technical Audit Report of North Anna Post-Seismic Fuel Inspections Virginia Electric and Power Company (Dominion)

North Anna Power Station Units 1 and 2

Audit Report for North Anna Post-Seismic Fuel Inspections

1. Scope and Purpose NRC staff conducted an audit of the post-seismic fuel inspections at the North Anna Power Station located at Mineral, Virginia on September 19 -22, 2011. The purpose of the North Anna audit was (1) to discuss the scope of the post-seismic fuel inspection along with the procedures and criteria for judging the condition of the fuel assemblies and (2) to witness the actual pool-side inspections to understand the capabilities of these inspections to identify fuel damage in support of NRC review of Dominion's restart submittal.

Audit Team:

Anthony Mendiola, NRR, Audit Team Leader Paul Clifford, NRR, Technical Reviewer Chris Van Wert, NRO, Technical Reviewer A list of Dominion participants in the audit is provided in Table 1-1.

Enclosure

Table 1-1: List of Dominion Attendees NAME - POSITION Audit RAI Audit Site Entrance Discussion Exit Executive Meeting JOHN GUERCI - Mgr, Nuclear Fuel Engineering X X X X RICH RIDDER - Supervisor, Fuel Performance X X X Analysis TOM BROOKMIRE - Supervisor, Nuclear Fuel X X X Projects LAUREN LOPEZ - Fuel Projects Engineer X TOM SHAUB - Corporate Licensing X X JAY LEBERSTIEN - Station Licensing X X X X MIKE LaPRADE - Supervisor, Engineering X X Primary Systems PAGE KEMP - Project Manager, Station X X X Improvement Initiatives JOHN SLATTERY - Assistant Manager, X X Operations ERIC HENDRIXSON - Director, Site X Engineering KERRY BASEHORE - Director, Nuclear X X X Analysis and Fuel CHRIS CLEMENS - Nuclear Fuel Projects X Engineer JOHN HARRELL - Manager, Nuclear Safety X Engineering (telecon)

DANA KNEE - Supervisor, Nuclear Safety X Analysis (telecon)

TODD FLOWERS - Supervisor, Nuclear Safety X Analysis Models and Methods (telecon)

PAULA LAROUERE - Consulting Engineer Fuel X Performance Analysis (telecon)

MIKE CRIST - Site Plant Manager X SAM HUGHES - Manager Operations X MAYO OPPENHIIMER - Manager, Systems X Engineering BOB SCANLAN - Manager, Site Services X BILL STANDLEY - Manager, Nuclear Oversight X TOM HUBER - Director, Nuclear Licensing and X Ops Suppori

2. Background 1 On August 23, 2011, at 1351 hours0.0156 days <br />0.375 hours <br />0.00223 weeks <br />5.140555e-4 months <br />, with North Anna Power Station Units 1 and 2 operating at 100% power, a magnitude 5.8 earthquake occurred approximately 5 miles from Mineral, Virginia. The epicenter was approximately 11 miles WSW of North Anna Power Station. Ground motion was felt and recognized as an earthquake by the Main Control Room operators at the station. The earthquake caused a series of reactor trip signals to both the Unit 1 and Unit 2 reactors, as well as a total loss of offsite power to the station. Per the Event Review Report, the "First Out" reactor trip signals for both units were "High Flux Rate Reactor Trip". Other than the trip signals and subsequent loss of offsite power, which were either directly or indirectly caused by the seismic event, safety systems in the plant responded as expected to the reactor trip and remained functionally undamaged and capable of performing their intended design functions.

Separately, the 2H Emergency Diesel Generator developed a coolant leak and was subsequently manually secured. A Root Cause Evaluation of the leak is being performed.

Based on evaluation of the US Geological Survey (USGS) data and plant specific seismic data analysis, Dominion has confirmed that the August 23, 2011 earthquake exceeded the spectral and peak ground accelerations for the Operating Basis and Design Basis Earthquakes ("OBE" and "DBE", respectively) for North Anna Power Station Units 1 and 2.

3. Discussion In preparation of the audit, the staff issued an audit plan (ADAMS MLI1 1259A1 580) which defined the purpose and scope of the audit. In parallel with preparing for the audit, DSS staff identified information needed to reach a safety finding with respect to restarting the North Anna units. In a letter dated September 14, 2011 (ADAMS ML11258A021 0), the staff issued a request for additional information (RAI).

During the seismic event on August 23, 2011, both North Anna units experienced a reactor trip on high flux rate - negative (i.e., decreasing neutron flux indication at excore detectors). The response of the reactor protection system and cause of the negative flux rate trip are still under root cause investigation and will be addressed separately. North Anna Unit 1 remains in Mode 5 while inspections continue. North Anna Unit 2 entered Mode 6 and began a refueling outage (approximately 1 month early).

Both North Anna Unit 1 and 2 reactor cores were comprised of 100% AREVA Advanced Mark-BW fuel assemblies at the time of the seismic event. Section 3.1 defines the NRC approval of the Advanced Mark-BW fuel assembly design and its design basis with respect to seismic requirements. Section 3.2 details the video inspections conducted on Unit 2 fuel assemblies.

Section 3.3 describes the RCCA drag load measurements being performed in the spent fuel pool. Section 3.4 describes the fuel inspections performed on fuel assemblies which resided in the spent fuel pool at the time of the seismic event.

3.1 Advanced Mark-BW Fuel Assemblies AREVA topical report BAW-1 0293(P)-A entitled, "Advanced Mark-BW Fuel Assembly Mechanical Design Topical Report," provides the design basis of the fuel within the North Anna cores. This topical report along with the staffs safety evaluation is available in ADAMS ML0428202010. Section 5.3.4 of BAW-10293(P)-A defines design criteria with respect to structural damage from external forces, including seismic requirements:

Operational Basis Earthquake (OBE):

I Background section taken from Dominion restart plan (ADAMS ML11262A1510)

• Allow continued safe operation of the fuel assembly following an OBE event by ensuring the fuel assembly components do not violate their dimensional requirements.

Safe Shutdown Earthquake (SSE):

• Ensure safe shutdown of the reactor by maintaining the overall structural integrity of the fuel assemblies, control rod insertibility, and a coolable geometry within the deformation limits consistent with the ECCS and safety analysis.

LOCA or SSE+LOCA:

• Ensure safe shutdown of the reactor by maintaining the overall structural integrity of the fuel assemblies and a coolable geometry within deformation limits consistent with the ECCS and safety analysis.

The example case in BAW-10293(P)-A showed that no plastic deformation occurred in the spacer grids when subjected to OBE and SSE loads. However, a limited amount of plastic deformation was measured on both intermediate spacer grids and IFMs for the combined SSE+LOCA impact force. Seismic analyses conclude that the maximum grid impact forces occur at intermediate grid locations of peripheral fuel assemblies adjacent to the core baffle.

The measured ground motion during the seismic event on August 23, 2011, exceeded the North Anna OBE. As a result, it is possible that horizontal and vertical acceleration at the core support plate and resulting loads applied on the Advanced Mark-BW fuel assemblies resulted in localized plastic deformation. Since the fuel was exposed to a seismic event beyond OBE, the Advanced Mark-BW fuel assemblies at North Anna are outside of the NRC's approval of topical report BAW-10293(P)-A and future operation with this fuel requires additional staff review.

The measured ground motion during the seismic event on August 23, 2011, exceeded the North Anna SSE (also referred to as design basis earthquake). As a result, it is possible that horizontal and vertical acceleration at the core support plate and resulting loads applied on the Advanced Mark-BW fuel assemblies resulted in localized plastic deformation. Since the fuel was exposed to a seismic event beyond SSE, the Advanced Mark-BW fuel assemblies at North Anna are outside of the NRC's approval criteria set forth in the staffs safety evaluation for topical report BAW-10293(P)-A and future operation with this fuel requires additional staff review.

AREVA Grid Crush Testing During the audit, the staff reviewed the AREVA grid crush test reports to better understand the buckling force and deformation characteristics of the Advanced Mark-BW grid cage designs.

" Knowledge of the buckling force is important to determine whether plastic deformation would be anticipated given the predicted loads associated with the August 23, 2011 seismic event.

• Knowledge of the failure point (i.e., weakest location in grid cage) and progression of deformation is important to judge the adequacy of visual inspection to detect plastic deformation.

AREVA (previously known as Framatome ANP) calculation 32-5027831-01, "MK-BW ZIRC-4 &

M5 External Grid Dynamic Properties," dated May 23, 2003, documents grid crush testing performed at MC/TP (LeCreusot, France) to determine dynamic buckling characteristics of Advanced Mark-BW 17x17 fuel assembly grids. The referenced test report 57-5028866-00, "Dynamic Buckling of Mark-BW and HTP Grid Assembly Test Report," dated June 5, 2003 provides more detail including photos of the post-test grids. Multiple tests were performed on

each grid type at Beginning-of-Life (BOL), as-fabricated conditions and simulated End-of-Life (EOL) conditions at 3250 C. Simulated EOL conditions achieved byI

.1Table 3.1-1 lists the results of the testing. Examination of this table (a, c) reveals [  ;.]The Zry-4 intermediate grids exhibited[ ]in buckling force and the M5 intermediate grids exhibited[ ]An AREVA representative at the audit stated that no reduction in IFM buckling force is expected[

]

Calculation 32-5027831-01 defines grid failure asp

.]Other failure indicators are (a, c) increased damping and unchanged or decreased impact force and equivalent stiffness for increased velocity. To measure the external or through-grid stiffness, a test grid is placed against a very stiff fixed support and then struck on the opposite face with a large mass. The impact velocity is gradually increased until the grid begins to crush, permitting a study of the behavior within the elastic range.

The staff intends to compare the Table 3.1-1 grid crush data against predicted fuel loading associated with the August 23, 2011 seismic event to determine if plastic deformation would be predicted to occur. See action item below.

Dominion Action Item:

The NRC staff requested that Dominion compile the existing design basis North Anna specific OBE, SSE, and combined SSE+LOCA applied loads on the grid cage and compare these against the measured buckling force for the Advanced Mark-BW M5 intermediate and IFM grid cage designs. In addition, Dominion would provide a conservative estimate of the August 2 3 rd seismic event and demonstrate that those accelerations remained below the buckling force.

Figures 3.1-1 and 3.1-2 illustrate the buckling characteristics of the Advanced Mark-BW M5 intermediate and IFM grids. Examination of these figures reveals that the entire grid cage structure buckles near the center plane, perpendicular to the applied load. Individual grid straps do not appear to break or deform independent of the entire grid structure and the outer grid strap proportional to interior straps. During the audit, an AREVA representative noted that the weakest point on the IFM grid cage design was the weld along the outer strap. In other words, this outer grid strap weld would fail following deformation of the outer row grid cells. This weld is shown in Figure 3.2-3 (between 2 nd and 3rd fuel rod from the right).

Based upon the established deformation characteristics of the Advanced Mark-BW grid cage design, it appears that a detailed visual inspection of the fuel assembly and outer grid strap would be capable of identifying grid buckling and deformation of the fuel rod lattice array.

Table 3.1-1: AREVA Grid Crush Test Results (Source: AREVA Calculation 32-5027831-00, dated May 23, 2003)

Spacer Grid Type CE Grid KE Favg F95%

Damping M5, BOL -- (a, c)

M5, EOL M5 IFM M5, IFM annealed Zirc-4, BOL Zirc-4, EOL Units kg/s  % E+6 N/m lbs lbs

Figure 3.1-1: Mark-BW IFM Grid Deformation following Impact Testing (Source: AREVA Test Report 57-5028866-00, dated June 5, 2003)

IMPACT 4 IDENTIFICATION (a, c)

Condifion

.. Temperature I Non-annealed

-325.

Figure 3.1-2: Mark-BW Intermediate Grid Deformation following Impact Testing (Source: AREVA Test Report 57-5028866-00, dated June 5, 2003)

IMPACT IDENTIFICATION (a, c)

EOL I T eCondition mpe ratu re . .... -3 2 5 =

3.2 Visual Inspection of Fuel Assemblies As documented in the North Anna Restart Readiness Determination report (ADAMS ML11262A1510), Dominion's approach to assessing damage to the fuel bundles consists of visual inspection. The following was extracted from this report:

Dominion is working with AREVA, the current fuel supplier for North Anna, to assess the margins in the fuel. For this evaluation, the acceptance criterion is that no plastic deformation is predicted. In addition, Dominion - with AREVA's input - has compiled a list of inspections to be conducted for fuel and fuel inserts in the new fuel storage racks and spent fuel pool, and during offload of the Unit 2 core, to verify the acceptability of the Unit 2 fuel for use or reuse. Unit 2 fuel will be examined prior to the Unit 1 startup. The Unit 2 fuel will be used to assess the condition of the Unit 1 fuel. If the Unit 2 fuel meets all of the inspection criteria described herein, no inspections of Unit 1 fuel are planned.

With respect to the irradiated AREVA fuel bundles which resided in the core during the seismic event, Dominion's restart report states:

The lateral clearances between fuel assemblies and between the fuel assemblies and the core baffle are very small. It is expected that any impact loading between assemblies was small enough that no damage to grids would have occurred. Binocular visual inspections of the Unit 2 assemblies are conducted during offload and during normal detailed visual inspection (using video) of a sample of the assemblies in the core. During these video inspections, additional attention will be given to the grids to look for distortion or any deflection of the inner grid straps and mixing vanes. As necessary, assembly movement will be stopped at grid elevations and camera angles will be varied to allow the best possible visual inspection of the grid structure. If the vertical acceleration was sufficient to lift the core and compress the top nozzle hold down springs, some indications may appear on the springs or on the corner pads if the springs bottomed out. Detailed inspections of the side of the nozzle when the benchmark inspections are being performed should identify any such damage to the nozzles.

During the audit, NRC staff reviewed the Dominion technical procedure for conducting fuel assembly visual inspections (NF-AA-FPA-502, Revision 4, "Irradiated Fuel Assembly and Insert Component Inspection"). As stated in this site procedure, all non-conforming conditions identified during the inspections necessitate a Condition Report. For example, two condition reports were generated during the audit to address foreign material discovered on two fuel assemblies. Inspection protocol includes identifying and documenting all of the following items:

o Fuel rod integrity including holes, cracks, blisters, and wear marks (fretting).

o Fuel rod bow.

o Fuel rod growth.

o Fuel rod unusual discoloration/crud/oxide.

o Grid damage.

o Debris.

o Fuel assembly envelope violation.

o Nozzle damage.

o Any other condition deemed significant by inspector.

Beginning Sunday, September 18, 2011, Dominion staff conducted visual inspection of 35 irradiated fuel assemblies from the Unit 2 core using a high resolution camera mounted in the

cask loading pit of the spent fuel pool. To support these inspections, AREVA provided a list of 20 fuel assemblies which resided in the most adverse Unit 2 Cycle 21 core locations with respect to predicted seismic impact loads. Figure 3.2-1 provides the Unit 2 Cycle 21 core loading pattern and highlights the 35 inspected assemblies. Note that the limiting seismic locations are along the flats at the core periphery. In addition to residing at the limiting seismic core location, many of the assemblies identified by AREVA were 3rd burned. Table 3.1-1 shows (a, c) that[ ] Therefore, these assemblies are good subset of the overall core population. Note that 'X', 'Y', and 'Z' in assembly alpha-numeric identification is the feed batch indicator for Cycles 19, 20, and 21 respectively (i.e., 'X' assemblies all 3 rd burned).

On Monday, September 19, 2011, NRC auditors witnessed video inspection of fuel assembly 2X5. Figure 3.2-1 shows that this 3 rd burned fuel assembly resided at a limiting seismic core location during Unit 2 Cycle 21. The visual inspection of this bundle lasted approximately 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and occurred at North Anna Fuel Building, Elevation 294'. The purpose of witnessing the visual inspection was to judge the capabilities of the inspection procedures and video equipment to identify damage. Figures 3.2-2 through 3.2-5 provide still shots from the inspection video captured during the fuel inspection campaign. As illustrated in these figures, the video equipment resolution was excellent; providing clear images of the fuel assembly components including the peripheral fuel rods and grid straps. No back lighting of the assembly was employed, but light reflecting off the cask loading pit wall provided visual indication of rod lattice conditions. Techniques such as rocking and twisting the assembly were used to view down rows of fuel rods for indications of rod bow or lattice deformation. No gross deformation was observed on fuel assembly 2X5.

At each grid location on all four faces of the assembly, the grid would be viewed from below (looking upward at approximately 450 angle), from straight away, and from above (looking downward at approximately 450 angle). The techniques and equipment employed during the visual fuel inspections are capable of identifying (1) anomalies along peripheral fuel rods and grid straps, (2) anomalies in the top and bottom nozzles, (3) rod bow, and (4) gross lattice deformation. However, as evident in Figures 3.2-2 through 3.2-4, the visual inspections have limited ability to identify deflected flow mixing vanes or minor plastic deformation within the center of the assembly.

During the audit, NRC staff reviewed video recording of the visual inspections for a sampling of the 35 fuel assemblies. The assemblies reviewed included:

• Assemblies 1X9, 3X0, 2X7, 2X4, and 3X9. 3rd burned assemblies located in limiting seismic core locations with[ .] These assemblies will be discharged. (a, c)

" Assembly 6Z0. 1 st burned assembly located in a limiting seismic core location. This assembly will be re-inserted in Cycle 22.

" Assemblies 2X8 and 5X0. 3 rd burned assemblies located along baffle with[

.1 The NRC review identified no signs of trauma on these assemblies which would indicate assembly-to-assembly or assembly-to-baffle impact loading due to seismic acceleration. This finding is consistent with Dominion's conclusion from their broader inspection campaign.

During its review of the video recordings, the NRC staff did identify an anomaly which prompted further investigation. Scratches and deformations on several of the outer grid straps were observed on peripheral fuel assemblies. Figures 3.2-6 and 3.2-7 show these markings.

Discussions with Dominion revealed that these grid strap markings are likely signs of assembly-

to-assembly rubbing or assembly-to-shroud rubbing (interaction) due to normal operation hydraulic driven oscillations and maybe also be due to fuel handling. The NRC auditors reviewed Dominion technical report NE-1565, Revision 0, "Fuel Performance Evaluation of North Anna 1 Cycle 20 and North Anna 1 Cycle 20 to Cycle 21 Refueling Outage Activities",

May 2009. This report contained discussion and photos of inspected fuel bundles with similar grid strap marking. Figure 3.2-8 contains photos of grid straps from prior cycles. These photos provide evidence that the grip strap scratches and deformations are unrelated to the seismic event.

In addition, the NRC staff observed several axial scratches on several fuel rods (likely due to manufacturing) and fuel rod bow on several assemblies. Both of these items were determined to be unrelated to the seismic event.

- 12-Figure 3.2-1: North Anna Unit 2 Cycle 21 Core Loading Pattern NORTH ANNA UNIT 2- CYCLE 21 FULL CORE LOADING PLAN REVISION NO. 0 PAGE I of 2 A B C D E F G H J K L M N P R VEP-NES-NA.F 15 2X7 I 2X5 3 X9 RCC RCC RCC 14 2Y0 6ZI 4Y0 6Z2 IY5 2X3 NORTH RCC 20P RCC - 13 I 2X9 4Z5 3Z0 5ý0 5Z4 5Y8 4Z8 3Z8 0X9 i RCC* RCC 24P 24p Rcc 12 5X5 2Y1 4Z7 1Y6 2Z7 2Y8 oZ5 IY8 2z9 1Y7 4x2 R~ ~ iýCwLn"

".~~~' (,Ai OXl 6Orf RCC RCC I 11 3ZI 5Z3 5Y6 _kZ2 3Y7 0Z3 6Y0 2Z5 3YM 3Z4 1ZI. 1X3 RCC 0Y5 RCC RCC CC CC RCC OPM 1 2C 10 454 2Y2 IZ6 lYI IZI 3Y5 IZ4 3Y IZ9 0Y9 4Z2 2Y9 RCC M  ; ROc A RCC RC 9 0 5Z7 4Y3 IZ2 4Y6 2ZI 4Y4 5Y7 3Y9 IZ3 6YI 2Z0 3Y6 i 6Z4 j 5X3 I 20P - RCC 0 RCC T 20P RCC 8 270-1 1X9 I R4Y71 3Z3 1Y2 0Z7 3Y2 5 2Y3 5Y2 3Y3 2Z8 IY9 3Z2 6Y3 3X3

~.eX IAIrV Eixi 5Z 2Y6 RcC 3Y4

."W iZO RCC 4Y8

-Ar 2Z6 RCC RCC 3Y0 ce I 3Y8 Ro 'M RCC M1W 4Y2

-P 0Z6 5Y3 RCC "?W 2Z3 RCC 6Y4 RCC *,TIM

(

6Z3 RCC 3X 5Z2 1Y4 2Z2 IYO IZ5 5Y4 1Z7 OY1 2Z4 0Y6 5Z1 0Y7

--' "Yw - iizF R-- 0 2 TV "?m RCC -f p 5 0X4I 3Z7 5Z6 6Y5 0Z4 4Y5 0.Z1 4Y7 0Z8 5Y9 3Z9 3Z5 0X2 RCC 5 RCC 24P 24P ROCC RCC 4 INCORE DEVICE DESCRIPTIONS

5X8 2Y) 4Z3 0Y4 0Z9 0Y3 Iz8 0Y2 5Z0 2Y4 6X3 RCC- FULL LENGTH CONTROL ROD 6P- 6 BURNABLE POISON ROD CLUSTTER 5 RCC 20P RCC "BF B-t - 3 18P- 18 BURNABLE POISON ROD CLUSTTER 5X6 5Z5 4Z0 6Y2 3Z6 5Y1 4Z6 4Z9 19P- 19 BURNABLE POISON ROD CLUSTTER RC_7 RCC RCC 20P- 20 BURNABLE POISON ROD CLUSTTER 1X5 IY3 5Z8 4Y9 6Z0 0Y8 3X2 24P- 24 BURNABLE POISON ROD CLUS. ER 0X6 I2X4 L4X3~

Prepared By: Concurrence By: 4 Date: I///0?

Reviewed BY: -9: Date.-010 Approved By: Date: o/q/00.

Approved By: k. AJ Date: so/s/oct

Figure 3.2-2: Illustration of Camera Resolution - Assembly 6Z0 Bottom Grid

Figure 3.2-3: Illustration of Camera Resolution - Assembly 6Z0 IFM Grid

Figure 3.2-4: Illustration of Camera Resolution - Assembly 2X7 Intermediate Grid

Figure 3.2-5: Illustration of Camera Resolution - Assembly 5X0 Top Grid

Figure 3.2-6: Peripheral Assembly Grid Strap Markings - Assembly 1X9 Intermediate Grid

Figure 3.2-7: Peripheral Assembly Grid Strap Markings - Assembly 3X9 Intermediate Grid

Figure 3.2-8: Peripheral Assembly Grid Strap Markings - Prior Cycles

3.3 Measure RCCA Drag Loads and Drop Times As documented in the North Anna Restart Readiness Determination report (ADAMS ML11262A1510), Dominion's approach to assessing damage to the fuel assembly guide tubes consists of visual inspection, RCCA drag load measurements, and hot rod drop testing. The following was extracted from this report:

When the units tripped during the recent seismic event, all control rods fully inserted.

However, testing will be performed to confirm that the rod cluster control assemblies (RCCAs) still freely travel within the fuel assembly guide tubes. After the Unit 2 offload, the RCCA drag loads will be measured in the spent fuel pool to assess whether the fuel assembly or the RCCAs have any distortion. Post-latch drag testing and hot rod drops of the RCCAs are already required as part of the normal start-up activities and will insure that the RCCAs and CRDMs are functional. A video inspection of the RCCA central hubs will be performed to provide additional confirmation of RCCA integrity. A satisfactory assessment of the Unit 2 RCCAs (rod drag measurements and spent fuel pool video inspections) will provide assurance that the Unit 1 RCCAs are in a similar condition. Although normally required only at BOC, hot rod drop testing of the Unit 1 RCCAs in accordance with normal station procedures will be performed prior to the restart of Unit 1 to confirm the continued acceptable condition of the Unit 1 RCCAs.

During the audit, NRC staff reviewed the Dominion operating procedure for conducting RCCA drag load measurements (0-OP-4.29, Revision 4, "RCC Drag Testing in Irradiated Fuel Assembly"). This operating procedure provides guidance and instruction for latching the RCCAs and performing the drag tests in the spent fool pool.

Beginning Thursday, September 22, 2011, Dominion staff conducted RCCA drag tests on the 48 rodded assemblies from Unit 2 Cycle 21. Additional drag tests will be performed once the RCCAs are moved from their current Cycle 21 assemblies to their Cycle 22 assembly locations.

The Unit 2 Cycle 21 core loading pattern, shown in Figure 3.2-1, identifies the rodded fuel assemblies from Cycle 21 and designates the re-inserted assemblies which will be placed in rodded location for Cycle 22. NRC staff witnessed several of the drag tests on Thursday, September 22, 2011. A load sensor is used to record the amount of force (beyond the RCCA hanging weight) necessary to lift the RCCA Up from the bottom of the guide tube (dash pot) to just below the top of the guide tube. The loads are recorded on a strip chart. Prior to leaving the audit, the maximum recorded drag force was less than 15 lbs. This amount of drag force is normal for this assembly design and indicates no deformation of the guide tubes due to the seismic event.

When the RCCA drag testing is complete, Dominion will provide the results to the NRC. This information will be used in the staffs safety evaluation for the restart readiness.

3.4 Spent Fuel Pool Inspections As documented in the North Anna Restart Readiness Determination report (ADAMS ML11262A1510), Dominion's approach to assessing damage to the fuel assembly residing in the spent fuel pool at the time of the seismic event consists of visual inspection. The following was extracted from this report:

The spent fuel pool rack cells are 8.875 inches square on the inside. There is slightly less clearance between\ the fuel and the cell walls in the spent fuel racks compared to the new fuel storage cells, and the potential for fuel damage in the spent fuel pool is further reduced by hydraulic damping effects. Nevertheless, the following inspections were performed:

Five new fuel assemblies scheduled for use in Unit 2 Cycle 22 that were placed into the spent fuel pool prior to the earthquake were video inspected for any signs of damage. These assemblies were inspected in accordance with the recommendations provided by AREVA.

During preparation of the spent fuel pool prior to the Unit 2 offload, a pre-offload fuel shuffle was performed. During this shuffle, a sample consisting of ten of these assemblies was also video inspected for any signs of damage.

When inspecting these irradiated assemblies, recommendations provided by AREVA were used to supplement Dominion's normal criteria for irradiated fuel inspections. The population of new fuel assemblies and pre-offload shuffle assemblies inspected provides a representative sample of the fuel designs and storage locations across the spent fuel pool.

The fuel assemblies examined during these inspections satisfactorily met the inspection criteria.

During the audit, NRC staff reviewed the Dominion fuel assembly inspection report of fuel residing in the SFP during seismic event. No evidence of grid tear or damage (GT) was identified or documented. "No anomalies observed" was marked in the inspection report for all but 1.assembly which recorded rod bow and associated envelope violation. Inspection included assemblies 2Xl, 0X8, 0V8, 4W0, 2W1, 0J5, 2W9, 5X9, 4W3, 32A.

In addition, the NRC staff reviewed surveillance video of the fuel building at SFP elevation (294')

showing beginning of seismic event prior to LOP. Video terminated before full seismic pulse (only initial shocks). Dominion personnel at this location reported small ripple in SFP water and no sloshing of the pool water. Dominion stated that the SFP water became occluded for following the earthquake and cleared up approximately 2 days after the event.

- 22 -

4. Audit Team Observations NRC staff conducted an audit of the post-seismic fuel inspections at the North Anna Power Station located at Mineral, Virginia on September 19 - 22, 2011. The purpose of the North Anna audit was (1) to discuss the scope of the post-seismic fuel inspection along with the procedures and criteria for judging the condition of the fuel assemblies and (2) to witness the actual pool-side inspections to understand the capabilities of these inspections to identify fuel damage in support of NRC review of Dominion's restart submittal. This audit report summarizes the staffs observations and impressions of North Anna's post-seismic fuel inspection procedures and capabilities. The staff's final assessment of the fuel will be documented in the NRC's safety evaluation of North Anna's Restart Readiness submittal.

The Audit Team would like to present the following Policy Issue:

Advanced Mark-BW current approval is based upon no deformation at OBE and SSE and limited, quantified assembly grid deformation at combined SSE+LOCA loads. If the actual seismic event prompts the re-evaluation of the North Anna SSE seismic envelope and the amplitude and frequency of the ground motion (and resulting loads on the fuel) increase, then the performance of the Mark-BW fuel under the new SSE+LOCA loads needs to be redefined and reanalyzed. The staff sees three possible paths:

a) If the NRC requires a new SSE spectrum be generated considering the August 2 3 rd seismic event, then North Anna must define the "new" OBE, SSE, and combined SSE+LOCA loads, test the AREVA fuel bundles, re-evaluate ECCS performance with the new grid deformation, and NRC would need to review it all.

b) If the NRC decides that the North Anna SSE envelope equals the August 2 3 rd seismic event, then North Anna must define the new SSE and combined SSE+LOCA loads, test the AREVA fuel bundles (or demonstrate applicability of existing tests), re-evaluate ECCS performance with the new grid deformation (if predicted loads exceed buckling), and NRC would need to review it all.

c) If the NRC decides that the existing North Anna SSE envelope remains applicable (as part of generic issues resolution), then the existing staff approval of Advanced Mark-BW fuel remains applicable.

Serial No. 11-544D Docket Nos. 50-338/339 Attachment 3 AREVA AFFIDAVIT Virginia Electric and Power Company (Dominion)

North Anna Power Station Units 1 and 2

AFFIDAVIT COMMONWEALTH OF VIRGINIA )

) ss.

CITY OF LYNCHBURG )

1. My name is Gayle F. Elliott. I am Manager, Product Licensing, for AREVA NP Inc. (AREVA NP) and as such I am authorized to execute this Affidavit.

2. I am familiar with the criteria applied by AREVA NP to determine whether certain AREVA NP information is proprietary. I am familiar with the policies established by AREVA NP to ensure the proper application of these criteria.

3. I am familiar with the AREVA NP information contained in the "Audit Report for North Anna Post-Seismic Fuel Inspections" for the NRC audit conducted at the North Anna Power Station located at Mineral, Virginia on September 19-22, 2011 and referred to herein as "Document." Information contained in this Document has been classified by AREVA NP as proprietary in accordance with the policies established by AREVA NP for the control and protection of proprietary and confidential information.

4. This Document contains information of a proprietary and confidential nature and is of the type customarily held in confidence by AREVA NP and not made available to the public. Based on my experience, I am aware that other companies regard information of the kind contained in this Document as proprietary and confidential.

5. This Document has been made available to the U.S. Nuclear Regulatory Commission in confidence with the request that the information contained in this Document be withheld from public disclosure. The request for withholding of proprietary information is made in accordance with 10 CFR 2.390. The information for which withholding from disclosure is

requested qualifies under 10 CFR 2.390(a)(4) "Trade secrets and commercial or financial information."

6. The following criteria are customarily applied by AREVA NP to determine whether information should be classified as proprietary:

(a) The information reveals details of AREVA NP's research and development plans and programs or their results.

(b) Use of the information by a competitor would permit the competitor to significantly reduce its expenditures, in time or resources, to design, produce, or market a similar product or service.

(c) The information includes test data or analytical techniques concerning a process, methodology, or component, the application of which results in a competitive advantage for AREVA NP.

(d) The information reveals certain distinguishing aspects of a process, methodology, or component, the exclusive use of which provides a competitive advantage for AREVA NP in product optimization or marketability.

(e) The information is vital to a competitive advantage held by AREVA NP, would be helpful to competitors to AREVA NP, and would likely cause substantial harm to the competitive position of AREVA NP.

The information in the Document is considered proprietary for the reasons set forth in paragraphs 6(b) and 6(c) above.

7. In accordance with AREVA NP's policies governing the protection and control of information, proprietary information contained in this Document have been made available, on a limited basis, to others outside AREVA NP only as required and under suitable agreement providing for nondisclosure and limited use of the information.

8. AREVA NP policy requires that proprietary information be kept in a secured file or area and distributed on a need-to-know basis.

OA

9. The foregoing statements are true and correct to the best of my knowledge, information, and belief.

SUBSCRIBED before me this dayof OCWkR4 2011.

Sherry L. McFaden NOTARY PUBLIC, COMMONWEALTH OF VIRGINIA MY COMMISSION EXPIRES: 10/31/14 Reg. # 7079129