ML11208B629

Exemption Request for Nuhoms Hd Dry Shielded Canisters Loaded to Incorrect Heat Load Limits

ML11208B629
Person / Time
Site:	Surry, 07200055
Issue date:	07/21/2011
From:	Hartz L Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Material Safety and Safeguards
References
11-251
Download: ML11208B629 (18)

Text

VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRcINA 23261 July 21, 2011 ATTN: Document Control Desk Serial No.11-251 Office of Nuclear Material Safety and Safeguards NLOS/TJS R1 U.S. Nuclear Regulatory Commission Docket Nos. 50-280 Washington, D.C. 20555-0001 50-281 72-55 License Nos. DPR-32 DPR-37 VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2 EXEMPTION REQUEST FOR NUHOMS HD DRY SHIELDED CANISTERS LOADED TO INCORRECT HEAT LOAD LIMITS Pursuant to 10 CFR 72.7, Virginia Electric and Power Company (Dominion) requests a one-time exemption from the requirements of 10 CFR 72.212(b)(3) and (b)(11) for NUHOMS HD Dry Shielded Canisters (DSC), Model Number HD-32PTH, with serial numbers DOM-32PTH-001-C, -002-C, -003-C, and -009-C due to a non-compliance with the terms and conditions of the Transnuclear, Inc. Certificate of Compliance (CofC)

Number 1030, Amendment 0, at the time of cask loading. The regulations require, in part, compliance to the terms and conditions of CofC 1030.

Contrary to this requirement, the four DSCs identified above were not loaded in compliance with CofC 1030, Amendment 0. The 32PTH DSC is designed for zoned loading with respect to decay heat. The four center locations are divided into an upper Zone "1b" and a lower Zone "l a" with the lower Zone "l a" locations allowing a greater decay heat than the upper Zone "l b" locations. The upper and lower orientation of the Zone "l b" and "l a" locations were reversed when preparing the DSC loading maps for the affected DSCs. As a result, fuel assemblies qualified to the Zone "la" decay heat limit were placed in Zone "1b" locations when the DSCs were loaded. It has been determined that the DSC Zone "l b" location decay heat limit was exceeded for five fuel assemblies distributed over the four affected DSCs at the time of loading.

Upon discovery, an extent of condition review was performed on all Surry DSCs. It was verified that all DSC loadings were below the total heat load limit for the DSC and the combined Zone 1a and Zone lb heat load limit at the time of loading. Only the decay heat limit for the individual fuel cell was exceeded at the time of loading for the five assemblies distributed over the four affected DSCs. The decay heat for the five affected assemblies currently meets the decay heat limit for their location within the DSC due to the time they have been in storage.

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Page 2 of 4 The design basis shielding analysis was verified to remain bounding for the as-loaded DSCs. The design basis shielding analysis assumes a DSC loading of 32 assemblies all having source terms applicable to assemblies generating 1.5 kW of decay heat and therefore bounds the as-loaded DSCs. The reactivity parameters for the fuel and DSCs were also verified to be unaffected by the loading error and therefore remain bounded by the design basis analysis assumptions.

A thermal evaluation which conservatively bounds the as-loaded configurations of the affected DSCs has been performed by Transnuclear, Inc., the CoC holder for the 32PTH DSC. This evaluation was performed consistent with the methods and assumptions used for the 32PTH DSC thermal analysis described in the NUHOMS HD Updated Final Safety Analysis Report (UFSAR). The evaluation concludes the fuel cladding temperatures did not exceed the fuel cladding temperature design limit of 4000C (752 0 F) for storage or transfer conditions. Further it shows that the DSC fuel compartment and support rail temperatures were bounded by those used in the design basis analysis, indicating there was no impact on the design basis structural evaluation of the DSC basket due to the loading error. The evaluation also concludes that the maximum DSC internal pressure remained below the design limit for the as-loaded configurations.

The four DSCs are currently considered operable and performing their intended safety functions. Post-loading surveillance parameters have been and continue to be within acceptable limits.

Details of Dominion's need and justification for the issuance of an exemption are included in Attachment 1. contains Transnuclear, Inc. Calculation Number 10494-174, "Effect of the Reversed Loading Patterns on the Thermal Performance of 32PTH DSC". This calculation is PROPRIETARY to Transnuclear, Inc. and is requested to be withheld from public disclosure in accordance with 10 CFR 9.17(a)(4) and 10 CFR 2.390(a)(4). An affidavit attesting to the proprietary nature of the information is provided in Attachment 2.

There are no commitments contained in this submittal.

If you have any questions or require additional information, please contact Mr. Thomas Szymanski at (804) 273-3065.

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Page 3 of 4 Sincerely, L. N. Hartz Vice President - Nuclear Support Services COMMONWEALTH OF VIRGINIA )

)

COUNTY OF HENRICO )

The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by L. N. Hartz, who is Vice President - Nuclear Support Services, of Virginia Electric and Power Company. She has affirmed before me that she is duly authorized to execute and file the foregoing document on behalf of that Company, and that the statements in the document are true to the best of her knowledge and belief.

Acknowledged before me this c'2\- day of 2011.U My Commission Expires: "-/ '\

Ginger Lynn RutherftW NOTARY PUBLIC Commonwealth of Virginia

• Reg. # 310847 My Commission Expires 4/30/2015 Nota Public Commitments made in this letter:

1. None Attachments:

1. Exemption Request

2. Transnuclear, Inc. Calculation No. 10494-174, Effect of the Reversed Loading Patterns on the Thermal Performance of 32PTH DSC with Affidavit attesting to proprietary nature of Calculation No. 10494-174 and request for withholding from public disclosure cc: U.S. Nuclear Regulatory Commission Region II Marquis One Tower 245 Peachtree Center Avenue, NE Suite 1200 Atlanta, Georgia 30303-1257

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Page 4 of 4 NRC Senior Resident Inspector Surry Power Station Ms. K. R. Cotton NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 G-9A 11555 Rockville Pike Rockville, Maryland 20852-2738 Mr. R. E. Martin NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 G-9A 11555 Rockville Pike Rockville, Maryland 20852-2738

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Attachment 1 Exemption Request Virginia Electric and Power Company (Dominion)

Surry Power Station Units 1 and 2

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Attachment 1 Request for Exemption from the Provisions of 10 CFR 72.212(b)(3) and (b)(11) to Allow the Continued Storage of NUHOMS HD DSC Loaded to Incorrect Heat Load Limits at SPS Table of Contents 1.0 Request for Exemption ............................................................. 2 2.0 Background .............................................................................. 2 3.0 Technical Considerations ......................................................... 3 4.0 Regulatory Considerations ....................................................... 4 5.0 Summary ................................................................................... 4 6.0 References .................................................................... 5 Page 1 of 10

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Request for Exemption from the Provisions of 10 CFR 72.212(b)(3) and (b)(11) to Allow the Continued Storage of NUHOMS HD DSC Loaded to Incorrect Heat Load Limits at SPS 1.0 Request for Exemption Pursuant to 10 CFR 72.7, Dominion requests a one-time exemption from the requirements of 10 CFR 72.212(b)(3) and (b)(1 1) for Transnuclear, Inc. NUHOMS HD 32PTH DSCs with serial numbers DOM-32PTH-001-C, -002-C, -003-C and -009-C due to a non-compliance with the terms and conditions of the Transnuclear, Inc. Certificate of Compliance (CofC) 1030, Amendment 0, at the time of cask loading. The regulations require, in part, compliance to the terms and conditions of CofC 1030. Contrary to this requirement, these four DSCs were not loaded in compliance with CofC 1030, Amendment 0. The 32PTH DSC is designed for zoned loading with respect to decay heat. The four center locations are divided into an upper Zone 1b and a lower Zone 1a with the lower Zone 1a locations allowing a greater decay heat than the upper Zone 1b locations. The upper and lower orientation of the Zone lb and la locations were reversed when preparing the DSC loading maps for the affected DSCs. As a result of this error, five fuel assemblies were placed in DSC locations where their decay heat at the time of loading slightly exceeded the Functional and Operating Limits established by CofC 1030, Amendment 0 Technical Specification Section 2.1. The five assemblies are distributed over the four DSCs identified above.

2.0 Background

The Transnuclear, Inc., NUHOMS HD 32PTH storage system, utilizes a dry shielded canister (DSC) designed to hold 32 spent fuel assemblies for independent spent fuel storage installation (ISFSI) deployment. The system commonly referred to as the NUHOMS HD 32PTH DSC or 32PTH DSC is listed in 10 CFR 72.214 as Certificate Number 1030. This system is currently installed and in use at the Surry Power Station under a general license. During an internal review of historical SPS NUHOMS HD System ISFSI Fuel Certifications on March 24, 2011, Dominion discovered that due to a miss-orientation of the Zone 1a and Zone 1b locations on the DSC loading maps, five fuel assemblies distributed over four DSCs had been loaded in a manner inconsistent with the CofC for the NUHOMS HD 32PTH storage system and exceeded the decay heat limit for their storage location (Figures 1 through 4).

Upon discovery of the condition, the actions contained in Appendix A, Section 2.2 of CofC 1030, Functional and Operating Limits Violations, were initiated. The affected fuel and DSCs were verified to be in a safe condition, the NRC Operations center was notified of the event within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (Reference 1) and a 30-day special report was sent to the NRC (Reference 2).

Page 2 of 10

Serial No.11-251 Docket Nos. 50-280/281, 72-55 The maximum decay heat of the five SPS affected fuel assemblies at the time of loading was 0.806 kW which exceeded the specific location limit of 0.8 kW by six watts. The five affected fuel assemblies have been in dry storage for a minimum of 2.5 years and all now meet their DSC location specific decay heat limit (Table 1).

No Technical Specifications (TS) changes for Surry Units 1 and 2 are required as this exemption request is only to be applied to the four DSCs identified.

3.0 Technical Considerations Upon discovery, an extent of condition review was performed on Surry DSCs. It was verified that the as-loaded configurations were below the total heat load limit for the DSC and the combined Zone 1a and Zone 1b heat load limit at the time of loading. Only the decay heat limit for the individual fuel cell was exceeded at the time of loading for the five assemblies distributed over the four affected DSCs. The decay heat for the five affected assemblies currently meets the decay heat limit for their location within the DSC due to the time they have been in storage.

Transnuclear, Inc. has performed a thermal analysis which conservatively bounds the as-loaded configurations of the affected DSCs (Attachment 2). This evaluation was performed consistent with the methods and assumptions used for the 32PTH DSC thermal analysis provided in the NUHOMS HD UFSAR. The evaluation conservatively assumed fuel assembly decay heat loads consistent with the UFSAR design basis loading pattern configuration that achieves the maximum fuel clad temperature results, with the exception of the Zone 1b locations. The decay heat for the Zone 1b locations was increased to 0.86 kW to bound the as-loaded (maximum 0.806 kW) heat loads of the Zone 1b locations. This analyzed configuration bounds the as-loaded decay heat conditions for the affected DSCs and conservatively increases the total DSC decay heat to greater than the current design basis analysis decay heat limit. Additionally this results in a combined Zone 1a and 1b total decay heat greater than the allowable decay heat for this region. Consistent with the NUHOMS HD UFSAR, the evaluation assumes an ambient temperature of 115 0F consistent with off-normal storage conditions for determining the maximum fuel cladding and component temperatures. This evaluation concludes the fuel cladding temperatures did not exceed the fuel cladding temperature design limit of 4000C (752 0 F) for storage or transfer conditions. Further it shows that the DSC fuel compartment and support rail temperatures were bounded by those used in the design basis analysis, indicating there is no impact on the current design basis structural evaluation of the DSC basket due to the loading error. The evaluation also concludes that the maximum DSC internal pressure remained below the design limit for the as-loaded configurations.

The design basis shielding analysis assumed a DSC loading of 32 assemblies having source terms applicable to assemblies generating 1.5 kW of decay heat (Reference 3).

Page 3 of 10

.1 Serial No.11-251 Docket Nos. 50-280/281, 72-55 As the Technical Specifications restrict the number of actual assemblies that can have a decay heat of 1.5 kW to eight, this significantly bounds the as-loaded DSCs providing assurance the design basis shielding analysis remains bounding.

Reactivity parameters for the fuel assemblies or DSCs were not affected due to the loading error. The reactivity parameters of the fuel at the time of loading met Technical Specification requirements as verified in the respective loading certification documents for each DSC.

The four affected DSCs are currently considered operable and performing their intended safety functions with associated surveillance parameters within acceptance limits.

4.0 Regulatory Considerations The specific requirements for granting exemptions to 10 CFR Part 72 licensing requirements are set forth in 10 CFR 72.7, Specific Exemptions, which reads as follows:

"The Commission may, upon application by any interested person or upon its own initiative, grantsuch exemptions from the requirements of the regulations in this part as it determines are authorized by law and will not endanger life or property or the common defense and security and are otherwise in the public interest." Dominion has determined that an exemption to 10 CFR 72.212(b)(3) and (b)(1 1) is necessary to allow continued storage of spent fuel assemblies in SPS ISFSI DSCs DOM-32PTH-001 -C, -002-C, -003-C and -009-C due to non-compliance with the terms and conditions of CofC 1030, Amendment 0, at the time of loading. Dominion's evaluation and Transnuclear, Inc.'s thermal analysis have determined that the affected DSCs remain bounded by the system's design basis limits.

Although the decay heat of the affected assemblies in the DSCs has decreased to within the CofC limits, loading fuel assemblies outside of location specific, heat load CofC limits is not allowed. Dominion requests an exemption in order to document the acceptability and safety basis for allowing the affected DSCs to remain loaded in their current configuration. An alternative exists to unload the four DSCs, however, it is Dominion's position that it would not be prudent to do so. Unloading the DSCs in question would subject station personnel to unnecessary radiation exposure, generate additional contaminated waste, increase the risk of a possible fuel handling accident, and increase the risk of a possible heavy load handling accident. Given that the Dominion and Transnuclear, Inc. evaluations performed support that the DSCs as-loaded are in a safe condition, an exemption to allow the continued storage of the four DSCs in their current configuration is justified and requested.

The requested exemption to continue to store fuel as-loaded in the four DSCs identified above has low safety significance and will not endanger life and property or the common defense and security. It is also in the public's interest to grant an exemption since the small improvement in safety margin achieved by unloading the affected DSCs Page 4 of 10

Serial No.11-251 Docket Nos. 50-280/281, 72-55 is not commensurate with the increased dose to station workers, increased risk of contamination, and increased risk of both a possible fuel handling accident and a possible heavy load handling accident during the unloading. Dominion considers that the requirements to grant an exemption pursuant to 10 CFR 72.7 have been met and that an exemption is justified.

5.0 Summary Dominion requests a one-time exemption from the requirements of 10 CFR 72.212(b)(3) and (b)(11) for Transnuclear, Inc. NUHOMS HD 32PTH DSCs stored at SPS with serial numbers DOM-32PTH-001-C, -002-C, -003-C and -009-C due to their non-compliance with the terms and conditions of CofC 1030, Amendment 0, at the time of loading. The regulations require, in part, compliance with the applicable CofC. Contrary to this requirement, four DSCs located at SPS were not loaded in compliance with CofC 1030, Amendment 0, in that a total of five fuel assemblies distributed over the four DSCs were loaded with a decay heat slightly in excess of that allowed for their storage location in the DSC. Dominion and Transnuclear, Inc. evaluations have determined the integrity of the four DSCs affected and the five fuel assemblies involved was not compromised due to the misloading. This one-time exemption will not endanger life or property or the common defense and security and are in ihe public interest and meet the intent of 10 CFR 72.7.

6.0 References

1. Reactor Plant Event Notification Worksheet, EN 46698, 03/24/11

2. Special Report on NUHOMS Dry Shielded Canisters Loaded to Incorrect Heat Load Limits, Serial No.11-244, 04/25/11

3. "Safety Analysis Report for the NUHOMS HD Horizontal Modular Storage System for Irradiated Nuclear Fuel", Transnuclear Inc.

4. NUHOMS HD Certificate of Compliance No. 1030, Amendment 0 Page 5 of 10

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Figure 1 DSC ID: DOM-32PTH-001-C Decay Heat at Time of Loading 4

1 22 3 4 3K4 11J8 2J5 3K7 954 797 799 978 1100 1500 1500 1100 Z2 Z3 Z3 Z2 Z2 1100 1 4. I 1100 I 5 6 7 8 9 10 4K6 4K7 4K8 5K2 5K4 5K8 940 958 950 959 971 972 1100 1100 1100 1100 1100 1100 Z2 Z2 Z2 Z2 Z2 11 12 13 15 16 3Y9 0V9 4U5 1V9 2V5 1149 782 782 787 797 1500 1100 800 1100 1500 Z3 Z2 ZIB Z2 Z3 17 18 19 20 21 22 4Y3 2V1 1G4 3G8 2V2 5V1 1150 792 758 754 795 796 1500 1100 1050 1050 1100 1500 Z3 Z2 ZIA ZIA Z2 Z3 23 24 25 26 27 28 2V9 3V0 3V8 4V2 4V3 5V4 781 783 787 781 778 795 1100 1100 1100 1100 1100 1100 Z2 Z2 Z2 Z2 Z2 Z2 29 30 31 32 6V3 3Y7 3Y6 6V4 785 1155 1133 781 1100 1500 1500 1100 Z2 Z3 Z3 Z2 Cell No.

F/A ID Decay Heat Total Decay Heat for DSC = 27,983 Watts Limit = 34,800 Watts (Wafts) Total Decay Heat for Combined Zones lb and la = 3,098 Watts Limit = 3,200 Watts Zone Limit (Wafts)

Zone ID Page 6 of 10

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Figure 2 DSC ID: DOM-32PTH-002-C Decay Heat at Time of Loading 1 2 3 4 21 B 03C 08C 51A 948 1116 1124 1046 1100 1500 1500 1100 Z2 Z3 Z3 Z2 5 6 7 8 9 10 09B 22B 23B 32B 15L 52A 951 944 942 936 1005 929 1100 1100 1100 1100 1100 1100 22 Z2 Z2 Z2 11 12 15 16 33B 17L 2H3 18L 40B 1237 1013 790 971 1258 1500 1100 800 1100 1500 Z3 Z2 B Z2 Z3 17 18 19 20 21 22 34B 20L 4U2 4U1 22L 41B 1225 1001 764 753 997 1362 1500 1100 1050 1050 1100 1500 Z3 Z2 ZIA ZIA Z2 Z3 23 24 25 26 27 28 60A 24L 25L 28L 30L 53A 933 973 966 992 995 943 1100 1100 1100 1100 1100 1100 Z2 Z2 Z2 Z2 Z2 Z2 29 30 31 32 56A 35B 38B 54A 1046 1293 1249 1090 1100 1500 1500 1100 Z2 Z3 Z3 Z2 Cell No.

F/A ID Decay Heat Total Decay Heat for DSC = 32,590 Watts Limit = 34,800 Watts (Wafts) Total Decay Heat for Combined Zones Ilb and la = 3,108 Watts Limit = 3,200 Watts Zone Limit (Watts)

Zone ID Page 7 of 10

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Figure 3 DSC ID: DOM-32PTH-003-C Decay Heat at Time of Loading 1 2 3 4 3K8 1K3 46A 3K9 953 959 1128 957 1100 1500 1500 1100 Z2 Z3 Z3 Z2 5 6 7 8 9 10 4K0 41<2 41<3 51<9 6K0 03A 965 952 953 959 961 1030 1100 1100 1100 1100 1100 1100 Z2 Z2 Z2 Z2 Z2 Z2 11 12 15 16 5Y5 11A* 15A 38A 1157 1059 1022 1151 1500 1100 1100 1500 Z3 Z2 Z2 Z3 17 18 19 20 21 22 61A 17A 0G8 IGI 21A 45A 1128 1015 760 755 1048 1157 1500 1100 1050 1050 1100 1500 Z3 Z2 ZIA ZIA Z2 Z3 23 24 25 26 27 28 27A 49A 57A 58A 59A 16B 1053 988 993 993 994 1030 1100 1100 1100 1100 1100 1100 Z2 Z2 Z2 Z2 Z2 Z2 29 30 31 32 27L 55A 02A 32L 1042 1141 1343 1043 1100 1500 1500 1100 Z2 Z3 Z3 Z2 Cell No.

F/A ID Decay Heat Total Decay Heat for DSC = 32,300 Watts Limit = 34,800 Wafts (Watts) Total Decay Heat for Combined Zones l b and la = 3,123 Watts Limit = 3,200 Watts Zone Limit (Watts)

Zone ID Page 8 of 10

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Figure 4 DSC ID: DOM-32PTH-009-C Decay Heat at Time of Loading 1 234 3 4 09A 02B0 03B 22A 982 1191 1278 980 1100 1500 1500 1100 Z2 Z3 Z3 Z2 5 6 7 8 9 10 26A 31 A 33A 3W3 3W5 3W9 990 980 985 1040 1052 1033 1100 1100 1100 1100 1100 1100 Z2 Z2 Z2 Z2 Z2 Z2 11 12 '13 14 15 16 14B 5W3 OJ9 01H 5W4 05B 1196 1061 804 800 1055 1195 1500 1100 °800.*0 800 1100 1500 Z3 Z2 Z ! >i. Z1 B Z2 Z3 17 18 19 20 21 22 13B 5W7 1G8 OV5 5W9 06B 1224 1087 764 774 1074 1197 1500 1100 1050 1050 1100 1500 Z3 Z2 Z1A Z1A Z2 Z3 23 24 25 26 27 28 6W7 3W4 4W2 2X9 3X1 3X8 1091 1075 1072 963 950 959 1100 1100 1100 1100 1100 1100 Z2 Z2 Z2 Z2 Z2 Z2 29 30 31 32 5Xl 08B 12B 48A 968 1259 1259 977 1100 1500 1500 1100 Z2 Z3 Z3 Z2 Z2 Z3 Z2 Cell No.

F/A ID Decay Heat Total Decay Heat for DSC = 33,310 Watts Limit = 34,800 Watts (watts) " Total Decay Heat for Combined Zones l b and la = 3,142 Watts Limit = 3,200 Watts Zone Limit (Wafts)

Zone ID Page 9 of 10

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Table 1 Fuel Assembly Decay Heat Verification Decay Heat at Time of Loading . _ I  : .- _

Burnup For Enrichment Last Cooling Decay Assembly Certification For Irradiation Time Heat Surry ID (GWD/MTU) Certification Date Loading Date (Years) (Watts)1 DSC 001 0V4 47.195 3.76 02/03/95 07/30/07 12.5 804 DSC 002 2H1 47.424 3.75 09/08/95 07/01/08 12.8 801 DSC 003 0V7 47.314 3.75 02/03/95 08/09/07 12.5 806 2V8 47.145 3.76 02/03/95 08/09/07 12.5 802 DSC 009 1 H6 46.968 3.76 09/08/95 01/01/08 12.3 804 Decay Heat at Date of Discovery Burnup For Enrichment Last Cooling Decay Assembly Certification For Irradiation Date of Time Heat Surry ID (GWD/MTU) Certification Date Discovery (Years) (Watts)1 DSC 001 0V4 47.195 3.76 02/03/95 03/24/11 16.1 728 DSC 002 2H1 47.424 3.75 09/08/95 03/24/11 15.5 743 DSC 003 0V7 47.314 3.75 02/03/95 03/24/11 16.1 731 2V8 47.145 3.76 02/03/95 03/24/11 16.1 727 DSC 009 1H6 46.968 3.76 09/08/95 03/24/11 15.5 733

1. Decay heat determined using CoC 1030 Amendment 0 Technical Specification Table 4.

Page 10 of 10

Serial No.11-251 Docket Nos. 50-280/281, 72-55 Attachment 2 Affidavit pursuant to 10 CFR 2.390(4) Request for Withholding from Public Disclosure Transnuclear, Inc. Calculation No. 10494-174 Effect of the Reversed Loading Patterns on the Thermal Performance of 32PTH DSC Virginia Electric and Power Company (Dominion)

Surry Power Station Units 1 and 2

A AR EVA Mr. Cary Laroe E-31109 Supervisor, Nuclear Engineering TN Project 10494 Dominion, Nuclear Analysis and Fuel June 21, 2011 500 Dominion Blvd Glen Allen, VA 23060

Subject:

Affidavit for TN Calculation 10494-174

Reference:

1. Dominion Master Services Agreement: 46017934

2. Dominion Release No.: 7010848

3. TN Calculation 10494-174 Attachments: Affidavit Pursuant to 10 CFR 2.390 Dear Mr. Laroe Please find attached an Affidavit concerning the proprietary nature of TN Calculation 10494-174 (Ref 3). TN recognizes that Dominion Resources will be using Ref 3 as an appendix to the following exemption letter:

For Surry:

Letter Serial No.11-251 Virginia Electric and Power Company Surry Power Station Units 1 and 2 Exemption Request for NUHOMS HD Dry Shielded Canisters Loaded to Incorrect Heat Load Limits For North Anna:

Letter Serial No.11-262 Virginia Electric and Power Company North Anna Power Station Units 1 and 2 Exemption Request for NUHOMS HD Dry Shielded Canisters Loaded to Incorrect Heat Load Limits Please attach the affidavit to the cover of the calculation (Ref 3) whenever submithing the document to the NRC as part of the aforementioned letter(s). Reference 3 is intended for Dominion use and is not intended for public dissemination.

If you have any questions, please feel free to contact me at (410) 910-6949 or Ken.Boone@AREVA.com.

Best Regards, Kenneth R. Boone Sr. Project Manger Cc: R. Robins TRANSNUCLEAR INC.

71 35 Minstrel Way Suite 300

• Columbia, MD 21045 Tel: 410-910-6900 Fax: 410-910-6902 www.transnuclear.com

AFFIDAVIT PURSUANT TO 10 CFR 2.390 Transnuclear, Inc.

State of Maryland County of Howard I, Jayant Bondre, depose and say that I am a Vice President of Transnuclear, Inc., duly authorized to execute this affidavit, and have reviewed or caused to have reviewed the information which is identified as proprietary and referenced in the paragraph immediately below. I am submitting this affidavit in conformance with the provisions of 10 CFR 2.390 of the Commission's regulations for withholding this information.

The information for which proprietary treatment is sought is listed below:

TN Calculation 10494-174 Rev 0: Effect of Reversed Loading Patterns on the thermal Performance of 32PTH DSC.

This document has been appropriately designated as proprietary.

I have personal knowledge of the criteria and procedures utilized by Transnuclear, Inc. in designating information as a trade secret, privileged or as confidential commercial or financial information.

Pursuant to the provisions of paragraph (b) (4) of Section 2.390 of the Commission's regulations, the following is furnished for consideration by the Commission in determining whether the information sought to be withheld from public disclosure, included in the above referenced document, should be withheld.

1) The information sought to be withheld from public disclosure involves details and analyses related to Transnuclear, Inc.'s design for the NUHOMS 32PTH Dry Shielded Canister, which are owned and have been held in confidence by Transnuclear, Inc.

2) The information is of a type customarily held in confidence by Transnuclear, Inc. and not customarily disclosed to the public. Transnuclear, Inc. has a rational basis for determining the types of information customarily held in confidence by it.

3) Public disclosure of the information is likely to cause substantial harm to the competitive position of Transnuclear, Inc. because the information consists of details and analyses related to Transnuclear, Inc.'s design for the NUHOMS 32PTH Dry Shielded Canister, the application of which provide a competitive economic advantage. The availability of such information to competitors would enable them to modify their product to better compete with Transnuclear, Inc., take marketing or other actions tc improve their product's position or impair the position of Transnuclear, Inc.'s product, and avoid developing similar data and analyses in support of their processes, methods or apparatus.

Further the deponent sayeth not.

Ji ant Bondr Vice President, Transnuclear, Inc.

Subscribed and sworn to me before this 21u day of June, 2011.

Noary Public A sLaurn

-~cm NMa ARY Mc i /201 PUBLIC Naryl.nd My Comimission Expires Aene AWNde County, Maryland v~*.*N$*

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