ML082620212

Response to the NRC Request for Additional Information Related to the Request for Temporary Exemption from the Provisions of 10 CFR 50.46 and 10 CFR 50, Appendix K for Lead Fuel Assemblies

ML082620212
Person / Time
Site:	Palo Verde
Issue date:	09/10/2008
From:	Mims D Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-05893-DCM/RKR, TAC MD8330
Download: ML082620212 (14)

Text

10 CFR 50.12 I-AMA subsidiary of Pinnacle West Capital Corporation Dwight C. Mims Mail Station 7605 Palo Verde Nuclear Vice President Tel. 623-393-5403 P.O. Box 52034 Generating Station Regulatory Affairs and Plant Improvement Fax 623-393-6077 Phoenix, Arizona 85072-2034 102-05893-DCM/RKR September 10, 2008 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

Reference:

NRC Letter dated August 11, 2008, from Mr. Michael T. Markley to Mr.

Randall K. Edington, Palo Verde Nuclear Generating Station, Unit 1 -

Request for Additional Information re: Request for Temporary Exemption from 10 CFR 50.46 and 10 CFR 50, Appendix K For Lead Fuel Assemblies (TAC NO. MD8330)

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Docket Nos. STN 50-528, 50-529 and 50-530 Response to the NRC Request for Additional Information Related to the Request for Temporary Exemption from the Provisions of 10 CFR 50.46 and 10 CFR 50, Appendix K for Lead Fuel Assemblies By letter dated March 08, 2008 (102-05826), Arizona Public Service Company (APS) submitted a request for a temporary exemption from the provisions of 10 CFR 50.46 and 10 CFR 50, Appendix K for Lead Fuel Assemblies (LFAs) for PVNGS Unit 1. In the referenced letter, the Nuclear Regulatory Commission (NRC) issued a request for additional information (RAI) and asked that a response be submitted within 30 days.

APS' response is enclosed.

This letter contains commitments described in Enclosure 2. If you have questions regarding this submittal, please contact Russell Stroud, Licensing Section Leader, Regulatory Affairs, at (623) 393-5111.

Sincerely,

,4oo(

A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway

• Comanche Peak

• Diablo Canyon 0 Palo Verde 0 San Onofre

• South Texas 0 Wolf Creek

ATTN: Document Control Desk U.S. Nuclear Regulatory Commission APS Response. to NRC RAI Related to the Request for Temporary Exemption for Lead Fuel Assemblies Page 2 DCM/TNW/RAS/RKR/gat

Enclosures:

1. APS Response to the NRC RAI related to the Request for a Temporary Exemption for Lead Fuel Assemblies

2. Commitments cc:

E. E. Collins Jr.

B. K. Singal R. I. Treadway NRC Region IV Regional Administrator NRC NRR Project Manager NRC Senior Resident Inspector for PVNGS APS Response to the NRC RAI related to the Request for a Temporary Exemption for Lead Fuel Assemblies APS Response to the NRC RAI related to the Request for a Temporary Exemption for Lead Fuel Assemblies NRC Question I The proposed temporary exemption will allow up to eight LFAs manufactured by AREVA NP with fuel rods with M5 to be inserted into the Palo Verde Unit 1 core in non-limiting locations. The LFAs are scheduled for use in three operating cycles of irradiation for Palo Verde Unit I (Cycles 15, 16, and 17). Please provide: (1) the analyses and methodologies used to identify the locations of the non-limiting locations; (2) the criteria and the key parameters used to determine the non-limiting locations; and (3) justification for the applicability of analyses for Cycle 15 to future Cycles 16 and 17 with respect to the analytic methods, key parameters, and non-limiting locations.

APS Response to NRC Question 1 (1)

Palo Verde Technical Specification (TS) 4.2.1 "Fuel Assemblies," states that "The reactor shall contain 241 fuel assemblies. Each assembly shall consist of a matrix of Zircaloy or ZIRLO fuel rods with an initial composition of natural or slightly enriched uranium dioxide (U0 2) as fuel material" and "Fuel assemblies shall be limited to those fuel designs that have been analyzed with applicable NRC staff approved codes and methods and shown by tests or analyses to comply with all fuel safety design bases. A limited number of lead test assemblies that have not completed representative testing may be placed in non-limiting core regions. Other cladding material may be used with an approved exemption."

Upon approval, APS will place eight AREVA Lead Fuel Assemblies (LFAs) employing M5 cladding and guide tube material and gadolinia burnable absorber in non-limiting core regions in the Unit 1 Cycle 15 core. APS has defined non-limiting core regions as meaning that the LFAs are designed and physically located in the core such that the peak integrated radial power peaking factor in the LFAs would be 0.95 or less of the core maximum integrated radial power peaking factor at each time in life. This criterion for a non-limiting core region is similar to that used in previous Combustion Engineering pressurized water reactor LFA programs at Waterford-3 and Calvert Cliffs.

APS designed the LFA lattice and Cycle 15 core during the core design phase of the reload effort. APS then verified in the core physics analyses that the placement of the LFAs in the Cycle 15 core would satisfy the criterion for non-limiting core regions, as previously defined above. In other words, the non-limiting core regions are not pre-identified as such, but verified to be non-limiting in the APS cycle-specific core physics calculations. The Cycle 15 core physics calculations performed by APS verify that LFA peak integrated radial power peaking factor is less than 0.95 of the core maximum integrated radial power peaking factor at each time in life. The AREVA LFAs are explicitly modeled in the Palo Verde core physics models, including the gadolinia burnable absorber.

As such, the impact of the LFAs is included in the Palo Verde cycle-specific core I

APS Response to the NRC RAI related to the Request for a Temporary Exemption for Lead Fuel Assemblies physics calculations supporting the reload effort. APS designed the LFA lattice, Cycle 15 core, and performed the reload analyses supporting the Cycle 15 reload using the STUDSVIK CASMO/SIMULATE Code package. The reload analyses performed by APS for Cycle 15 are the same analyses performed for a standard Palo Verde Reload and are consistent with the current Core Operating Limits Report (COLR) methodology references (Palo Verde TS 5.6.5). The reload methodology used by APS is the Westinghouse (ABB-CE) reload methodology. The NRC previously approved APS' use of both the STUDSVIK CASMO/SIMULATE code package for Palo Verde including the use of gadolinia burnable absorber and the Westinghouse (ABB-CE) reload methodology (references 1 and 2, respectively).

An underlying assumption of the LFA program was that a 5% power peaking penalty would be sufficient to ensure that the LFAs would be non-limiting in the safety, fuel performance, thermal-hydraulic, and Emergency Core Cooling System (ECCS) performance analyses. The 0.95 power peaking factor criterion applied to the LFA is a means of applying a 5% penalty to the LFA. This 5%

penalty provides additional Departure from Nucleate Boiling (DNB) and Loss of Coolant Accident (LOCA) margin to ensure that the LFA is non-limiting. Since the LFAs will not be in the highest core power density locations, the placement scheme assures that the behavior of the LFAs is bounded by the safety analyses performed for the co-resident fuel assemblies. This is verified by analyses performed by APS, AREVA, and Westinghouse. Additionally, the maximum LFA integrated fuel rod burnup will be maintained less than or equal to 60 MWd/kgU, the Palo Verde limit in Updated Final Safety Analysis Report (UFSAR) section 4.3.1.1 "Excess Reactivity and Fuel Burnup."

In addition to satisfying the power peaking factor criterion for a non-limiting region, the placement of the eight (8) LFAs in Cycle 15 will be toward the interior of the core in order to accumulate duty and burnup. Figure 1 shows the Cycle 15 locations of the 8 LFAs in bold shaded highlight; the core grid locations are provided in the note at the bottom of the figure.

(2)

The non-limiting core regions are not identified or determined as such, but verified to be non-limiting in the cycle-specific core physics calculations. The criteria used to verify that a core region is non-limiting with respect to the LFAs is the peak integrated radial power peaking factor in the LFAs, as physically located in the Cycle 15 core, being 0.95 or less of the core maximum integrated radial power peaking factor at each time in life. The key parameter used to verify that the core region is non-limiting is integrated radial power peaking factor. As stated in the response to item (1) above, the 95% power peaking factor criterion applied to the LFA is a means of applying a 5% penalty to the LFA. This 5%

penalty provides additional Departure from Nucleate Boiling (DNB) and Loss of Coolant Accident (LOCA) margin to ensure that the LFA is non-limiting. Since the LFAs will not be in the highest core power density locations, the placement 2

Enclosure I APS Response to the NRC RAI related to the Request for a Temporary Exemption for Lead Fuel Assemblies scheme assures that the behavior of the LFAs is bounded by the safety analyses performed for the co-resident fuel assemblies.

(3)

In Cycle 16, four (4) of the LFAs will be located in the core interior and four (4) on the core periphery. In Cycle 17, four (4) or eight (8) LFAs will be located on the core periphery. Scoping fuel managements were done for Cycles 16 and 17 to determine design feasibility. For future Cycles 16 and 17, APS will perform explicit neutronics modeling and analysis of the AREVA LFAs using the STUDSVIK CASMO/SIMULATE code package in the same manner as was performed for the lead cycle, Cycle 15. The physical placement of the LFAs in these cycles in addition to their being once or twice burned will ensure that the LFAs will continue to operate at power peaking factors lower than the 0.95 power peaking criterion used in Cycle 15, thereby ensuring that the LFAs remain in non-limiting locations (i.e., core regions). The analyses performed for Cycles 16 and 17 will use the same generic, cycle-independent methodologies employed in Cycle 15. Cycle 16 and Cycle 17 specific power distribution data obtained from the neutronics models will be used in the evaluation and analysis of the LFAs in each cycle.

NRC Question 2 Please provide clarification in terms of key parameters that: (1) the ECCS performance would not be adversely affected due to the similarities in the material properties of the M5 alloy to Zircaloy or ZIRLO and the location of LFAs in non-limiting locations; and (2) the application of the Baker-Just equation will continue to bound all post-LOCA scenarios for M5 alloy conservatively.

APS Response to NRC Question 2 (1)

From an ECCS performance analysis perspective, the AREVA LFAs were evaluated relative to the co-resident Westinghouse batch fuel. Thermal-hydraulic and geometrical differences between AREVA and Westinghouse fuel designs were evaluated. Clad swell, rupture and oxidation, fuel assembly power, peak cladding temperatures (PCTs), Small Break Loss-of-Coolant Accident (LOCA), coolable geometry, long-term cooling, and gadolinia burnable absorber were considered. The U-235 enrichment of the gadolinia fuel rods is reduced relative to the highest enrichment rod in the LFA, consistent with the AREVA Core Design Guidelines. The gadolinia fuel rod enrichment reduction ensures that the gadolinia bearing fuel rods are non-limiting and bounded by the uranium dioxide fuel rods.

APS has concluded, based primarily on the 5% radial power peaking penalty and the conclusion that this 5% margin dwarfs various offsetting effects due to minor differences in geometry and initial pin pressure, that the LFAs would be non-3 APS Response to the NRC RAI related to the Request for a Temporary Exemption for Lead Fuel Assemblies limiting relative to the batch fuel. This assures that the LFAs are covered by the Westinghouse Analysis of Record (see response to Question 3 for more details) and thus would comply with the criteria of 10 CFR 50.46.

(2)

USNRC report NUREG/CR-6967 (ANL-07/04), "Cladding Embrittlement During Postulated Loss-of-Coolant Accidents," (NRC ADAMS Accession No. ML082130389) identified the importance of the Baker-Just equation relative to LOCA accident evaluations stating that "This mechanism (diffusion of oxygen into the metal) was also understood in 1973 and is accommodated by the 17% ECR

[equivalent cladding reacted] limit in NRC's regulation, provided oxidation is calculated with the Baker-Just correlation that was used in deriving the limit."

Framatome Cogema Fuels (FCF), now AREVA, has previously performed high temperature oxidation tests for M5 cladding to confirm that the Baker-Just oxidation correlation remains conservative for M5 cladding.

A comparison of M5 cladding measured values to Baker-Just predictions demonstrated that the Baker-Just correlation remained conservative for temperatures typically calculated for LOCA, up to 1250 0C (-2280 'F). The NRC staff asked FCF to provide Arrhenius plots of the high-temperature oxidation data in order to provide a measure of bias and uncertainty in the data. FCF provided these plots which demonstrated only small uncertainties and essentially no biases in the data. The FCF data demonstrates that high-temperature oxidation of the M5 alloy cladding is bounded by the Baker-Just correlation and that the Appendix K requirement for the use of Baker-Just remains conservative in relation to the use of M5 cladding. This conclusion is documented in the NRC Safety Evaluation (SE) dated February 4, 2000, for FCF Report No. BAW-1 0227-A, "Evaluation of Advanced Cladding and Structural Material (M5) in PWR Reactor Fuel," dated February 2000 (NRC ADAMS Accession No. ML003686365).

The NRC staff has subsequently reaffirmed this conclusion regarding the applicability of Baker-Just to M5 cladding for post-LOCA scenarios in the NRC SE associated with a similar exemption for ANO-1 to use M5 clad fuel assemblies in its PWR (July 2005) stating that "...TR BAW-10227P demonstrated the Baker-Just equation (used in the ECCS evaluation model to determine the rate of energy release, cladding oxidation, and hydrogen generation) is conservative in all post-LOCA scenarios with respect to M5 advanced alloy as a fuel rod cladding material." (NRC exemption approval for Arkansas Nuclear One, Unit 1 -

Exemption From 10 CFR 50.46 and 10 CFR Part 50, Appendix K (TAC NO.

MC4612), dated July 25, 2005 (NRC ADAMS Accession No. ML051790417).

4 APS Response to the NRC RAI related to the Request for a Temporary Exemption for Lead Fuel Assemblies NRC Question 3 Please describe the joint effort with respect to roles to be played between APS, AREVA, and Westinghouse for evaluations: (1) to verify performance of the LFAs with respect to the safety analysis such as thermal-hydraulic compatibility, loss-of-coolant accident (LOCA) and non-LOCA criteria, mechanical design, seismic and core physics; and (2) to verify the insertion of the AREVA LFAs does not adversely impact the fuel performance and mechanical integrity of the co-resident fuel.

APS Response to NRC Question 3 (1)

APS' AREVA LFA design and engineering effort required the resources and coordination of all three organizations, APS, AREVA, and Westinghouse. While each organization had its own project manager, the APS project manager maintained overall responsibility for the design effort. APS conducted weekly teleconferences between APS and AREVA and between APS and Westinghouse to coordinate the project. As necessary, APS facilitated three-way teleconferences to exchange information and resolve issues. APS participated in a three-party proprietary information agreement which allowed for a candid and unrestrained exchange of technical information to ensure the compatibility of the LFAs with the Palo Verde co-resident fuel and core internals.

APS acted as the intermediary between AREVA and Westinghouse to ensure that each organization had the necessary and appropriate inputs to perform their analyses. APS had responsibility for the LFA and core design, physics analyses, and base scope reload analyses typically performed to support a standard Palo Verde Reload.

AREVA was responsible for the testing and analyses supporting the LFA.

AREVA conducted flow tests on both the AREVA LFA and the Westinghouse co-resident fuel assembly using identical geometries and test conditions to determine and compare hydraulic characteristics. The AREVA analysis scope included the mechanical design and analysis of the LFAs, the thermal-hydraulics/DNB performance analysis, fuel performance analysis, LOCA evaluation, CEA Ejection/Fuel Centerline Melt Analysis, and the combined seismic and LOCA loads. Westinghouse performed a Compatibility Analysis to verify that the insertion of the AREVA LFAs does not adversely impact the fuel performance and mechanical integrity of the co-resident Westinghouse fuel.

To assess the impact of the LFAs on the safety analyses, Westinghouse conducted detailed evaluations in several functional areas such as Structural/Seismic Analysis, Mechanical Design, Emergency Core Cooling System Performance, LOCA Dose Assessment, Thermal Hydraulics, and Criticality Safety.

5 APS Response to the NRC RAI related to the Request for a Temporary Exemption for Lead Fuel Assemblies (2)

As part of the LFA program, Westinghouse performed a Compatibility Analysis to verify that the insertion of the AREVA LFAs does not adversely impact the fuel performance and mechanical integrity of the co-resident Westinghouse fuel. To assess the impact of the LFAs on the safety analyses, Westinghouse conducted detailed evaluations in several functional areas such as Structural/Seismic Analysis, Mechanical Design, Emergency Core Cooling System Performance, LOCA Dose Assessment, Thermal Hydraulics, and Criticality Safety.

Westinghouse used their NRC approved codes and methods in their analyses supporting the AREVA LFAs.

In the APS request for the cladding exemption for the Lead Fuel Assemblies1 it was stated that "the effectiveness of the ECCS in Palo Verde Unit 1 will not be affected by insertion of eight LFAs." However, the Westinghouse Emergency Core Cooling System Performance evaluation (in the initial Compatibility Analysis transmitted to APS, July 14, 2008) identified a 4 OF impact to the calculated PCT in the Westinghouse fuel due to the presence of the LFAs. It should be noted that the Westinghouse Compatibility Analysis and the Palo Verde LBLOCA analysis of record (AOR) are very conservative relative to the current Palo Verde Unit 1 Cycle 15 reload design. These conservatisms include the following:

The AREVA LFAs have been measured to have a 3% higher pressure drop, but for the purposes of the Westinghouse evaluation the LFAs were conservatively analyzed with a 16.5% higher pressure drop.

The Westinghouse AOR evaluated fuel rod designs with both Zircaloy-4 and ZIRLO cladding. The Westinghouse AOR limiting ECCS Performance Analysis PCT results are based on the more limiting fuel rod design, which is Zircaloy-4 cladding. This fuel rod design and cladding type have been replaced in current Palo Verde core designs with a less limiting fuel rod design with ZIRLOTM cladding. However, the limiting ECCS Performance Analysis results continue to be conservatively based on the previous cladding type.

The Westinghouse AOR limiting ECCS Performance Analysis results are based on an assumed core integrated radial peaking factor of 1.65 at full power, all rods out. The actual calculated value for the Unit 1 Cycle 15 core is 1.41. This conservatism alone will more than compensate for the 4 OF PCT adder recommended by the Westinghouse Compatibility Analysis.

Based upon the Westinghouse Compatibility study, Palo Verde Unit 1 Cycle 15 with the insertion of eight AREVA LFAs will continue to meet all of the regulatory limits of 10 CFR 50.46 (PCT less than 2200 °F, maximum localized clad oxidation less than 17%, Total Core Wide oxidation less than 1 %, a coolable geometry is maintained and the capability for Long Term Cooling of the core is demonstrated).

The current Palo Verde Unit 1 PCT margin assessment indicates no need for a 1 (APS letter 102-05826, dated March 08, 2008) 6 APS Response to the NRC RA! related to the Request for a Temporary Exemption for Lead Fuel Assemblies 30-day report for this small (4 OF) change in PCT. Based upon this new information, it is APS's intention to include the additional 4 OF PCT adder in the Emergency Core Cooling System (ECCS) Performance Evaluation Models and 10 CFR 50.46(a)(3)(ii) Annual Report for Calendar Year 2008 to conservatively account for the impact of inserting the AREVA LFAs in the Unit I Cycle 15 reload core.

NRC Question 4 It appears that Commitments 4, 5, and 6 (attached to the Palo Verde application dated March 8, 2008) will be completed by October 30, 2008. Please describe methodologies and data used to evaluate the Palo Verde core physics models, thermal-hydraulic/neutronic compatibility, and impact on the co-resident fuels with respect to insertion of the AREVA LFAs.

APS Response to NRC Question 4 To evaluate the impact of the LFAs on the co-resident fuel, APS performed explicit core physics modeling and analysis of the AREVA LFAs using the STUDSVIK CASMO/SIMULATE code package. The AREVA LFAs are explicitly modeled in the Palo Verde core physics models, including the gadolinia burnable absorber. As such, the impact of the LFAs is included in the Palo Verde cycle-specific core physics calculations supporting the reload effort. APS uses the STUDSVIK CASMO/SIMULATE code package to design the Palo Verde cores and to perform the reload analyses. The reload analyses performed by APS for Cycle 15 are the same analyses performed for a standard Palo Verde Reload. Additional analyses were performed to support AREVA and Westinghouse data requests. The reload methodology used by APS is the Westinghouse (ABB-CE) reload methods which are consistent with the current COLR methodology references. The NRC previously approved APS' use of the STUDSVIK CASMO/SIMULATE code package for Palo Verde including the gadolinia burnable absorber and the Westinghouse (ABB-CE) reload methodology (references 1 and 2, respectively).

Each Fuel vendor used their respective NRC approved codes and methods in their analyses supporting the AREVA LFAs. As previously stated, APS acted as the intermediary between AREVA and Westinghouse to ensure that each organization had the necessary and appropriate inputs (data) to perform their analyses. For example, AREVA transmitted various geometric and dimensional information, grid loss coefficients, first six natural frequencies and mode shapes, lateral stiffness, critical damping ratios, and impact stiffness data to Westinghouse. Similarly, Westinghouse transmitted various geometric and dimensional information, various mechanical design information, fuel assembly first six natural frequencies and mode shapes, lateral load vs. deflection, and vertical LOCA force data to AREVA. APS transmitted to AREVA such information as the LFA lattice design, Cycle 15 core locations, fuel rod power 7

Enclosure I APS Response to the NRC RAI related to the Request for a Temporary Exemption for Lead Fuel Assemblies histories, peaking distortion factors for CEA Ejection, core limiting state points for DNB analysis, and core characteristics (temperatures, pressures, flow) information. See the response to question 3, item (2) for the affects on co-resident fuel.

References

1. Safety Evaluation by the Office of Nuclear Reactor Regulation Related to Amendment No. 132 to Facility Operating License No. NPF-41, Amendment No.

132 to Facility Operating License No. NPF-51, and Amendment No. 132 to Facility Operating License No. NPF-74, Arizona Public Service Company, et al, Palo Verde Generating Station, Units 1, 2, and 3, Docket Nos. STN 50-528, STN 50-529, and STN 50-530, March 20, 2001. (TAC NOS. MA9279, MA9280, AND MA9281)

2. Safety Evaluation by the Office of Nuclear Reactor Regulation Relating to on-Site Audit of Palo Verde Reload Analysis Methodology, Arizona Public Service Company, Docket Nos. 50-528, 50-529, 50-530, June 14, 1993. (TAC NOS.

M85153, M85154, AND M85155) 8 APS Response to the NRC RAI related to the Request for a Temporary Exemption for Lead Fuel Assemblies Figure 1 PVNGS Unit I Cycle 15 Full Core Load Map Full Core Loading. Map for The Next Cycle of Palo Verde Unit 1 Key to Map Assembly Serial Number Orientation (N,E,S,W)

W121 N Assembly Location P3HO01 Assembly Serial Number S

0 E Location of Assembly in Previous Cycle vS T

S R

P N

M L

K J

H G

F E

D C

B A

17 16 15 14 13 12 11 10 9

8 7

62

• PIR201 82 79 52 96 PIR420 128 113 PIR508 129 130

• PIR403 188 147

• PIR110 186 164 PIR202 150 32 PIR301 24 47 PlR211 112 63

• PIT101 80

• PIT207 97

• PIT202 114

• PIT206 131

• PIT213 148

• PlT228 165 PlT03 181

• PIR203 146 196

• PIR307 216 8

• PIR308 98 19 20

• PlR410 PlTl14 85 33

• 34

• PlT115 PIT302 48 49

• P1T209 P1S402 101 64

• 65

• PIS306 PIT415 15 81

• 82

• PIT422 PIS516 44 98 -

99

• P1S504 PIT5 03 27 115

• 116

• PIS101 PIS514 10 119 132

• 133

• P1S5211 PIT505.

219 149

• 150

• PIT419 P1S508 I25 166

• 167

• PIS308 PIT405 231 182

• 183

• PIT216 PIS403 135 197

• 198

• PlT104 PIT304 211

• 212

• PIR412 PlT113 153-......

224

• PIR302 132 9*

PIR210 237 21 PIT212 35

• PIS404 69 50 PIT411 66 PIS416 50 83

• PIT431 100

• PIS503 85 117

• 209 134 P1S526 167 151 PIT423 168 P1S411 105 184

• PIT439 199

• P1S420 171 213

• PIT227 225

• PIR207 3

i*

PIR212 37 10 PIT102 22 PIS311 148 36 PIT402 51 PIS410 139 67 PlS116 179 84 PIS206 194 101 PIS314 14 118 PIS408 67 135 PIS316 230 152 PIS208 60 169 Pl1S08 16 185 PIS409 184 200 PIT440 214 PIS312 80 226 PlT105 235 PIR206 201 2*

PIR114 83 11 PIT203 23 PIT428 37 P10510 127 52 P1T433 68 P1S207 221 85 PIT427 102 P1R504 62 119 PIT403 136*

PIR509 164 153 PlT437 170 PIS201 29 186 PIT407 201 PIS515 34 215 PIT406 227 P1T223 236 PIR104 151 3*

PIR408 117 12 PIT219 24 PIS527 149 38 PITS07 53 PIS502 36 69 PIS313 131 86 PIR505 1

103 PIT438 120 PIS103 45 137 PIT426 154 PIR511 235 171 PIS304 97 187 P1S525 200 202 PlTS02 216 PIS511 81 228 PIT224 237 PIR407 13 4*

PIR510 238 13

• PIT220 25

• Pl1S02 77 39

• PIS524 87 54 PIS109 212 70 PlS405 73 87 PIT409 104 P1S106 222 121 PIM339 138

• PIS107 20 155 PIT414 172

• PIS407 169 188 30 203 PIS505 155 217 PIS113 165 229 PIT208 238

• P1R512 4

---;-* --7--

P1R405 P1R115 229 91 14

• 15 P1T222 PIT225 26

• 27

• P1S512 PIT421 161 40

• 41

• PlTS06 P1S517 208 55

• 56

• P1S528 PIT424 42 71

• 72*

P1S303 P1S203 145 j 213 88

• 89 PIR513 PIT436 105

• 106

• PIT430 PIR503 78 122

• 123

• P1S104 PIT435 197 139

• 140

• PIT429 PIR501 180 156

• 157

• PlR506 PIT420 241 173

• 174

• P1S302 PIS205 111 21 189

• 190

• P1S523 PIT425 206 204

• 205

• PlT504 PIS507 115 218

• 219

• P1S520 PIT412 93 230

• 231

• PlT205 P1T217 239

• 240

• P1R402 PIR106 125 159 7*

P1R204 41 16 PlTl10 28 P1S315 162 42 PIT432 57 PIS413 58 73 Pl1S05 226 90 PIS204 182 107 PIS309 12 124 PIS406 175 141

• PIS301 228 158 P1S202 48 175 PIS114 63 191 PIS418 103 206 PlT410 220 PIS305 94 232 PlT108 241

• PIR209 205 17

• PIR214 239 29

• PIT221 43

• PIS401 71 58*

PIT404 74

• PIS414 137 91 PIT408 108

• P1S506 75 125

• 33 142

• PIS513 177 159

• PIT413 176

• P1S415 192 192

• PlT401 207

• PIS419 173 221 P1T204 18

• PlR305 110 30

• PIT107 44

• PIT303 59

• P1S412 107 75

• PIT416 92

• PIS509 217 109

• P1T501 126

• PIS501 123 143 160

• P1S518 198 177

• PIT434 193 PIS417 141 208 PIT301 222

• PlT106 31 PIR411 89 45 PlT112 60 PIT210 76 PIS310 11 93 PlT417 110

• PIS519 23 127 PIS115 232 144 PIS522 215 161 PIT418 178

• PIS307 227 194 PIT214 209 PlT109 223

• PIR409 157 46 PIR303 26 61 PIR216 96 77*

PlTlll 94 PlT215 PlT211 128 PIT201 145 PlT218 162 PIT226 179

• PIT116 195*

PIR215 130 210 PIR306 218 78

• PIR208 92 95 P1RI01 56 112 PIR401 54 129 P1R507 113 146 PIR404 114 163 PIR102 190 180 PIR205 160 4

3 233

• 234

• P1R213 P1R304 5

144 Note:

The AREVA LFAs are located in Core Grid Locations K-14, H-14, P-10, D-10, P-8, D-8, K-4, and H-4.

9

ENCLOSURE 2 Commitments Commitments

1. For Unit 1 Cycle 16, APS will perform explicit neutronics modeling and analysis of the AREVA LFAs using the STUDSVIK CASMO/SIMULATE code package in the same manner as was performed for Cycle 15. The analyses performed for Cycle 16 will use the same generic, cycle-independent methodologies employed in Cycle 15. Cycle 16 specific power distribution data obtained from the neutronics models will be used in the evaluation and analysis of the LFAs in this cycle. (Question 1, Item 3 response, RCTSAI 3220607, Due 4/30/2010)

2. For Unit I Cycle 17, APS will perform explicit neutronics modeling and analysis of the AREVA LFAs using the STUDSVIK CASMO/SIMULATE code package in the same manner as was performed for Cycle 15. The analyses performed for Cycle 17 will use the same generic, cycle-independent methodologies employed in Cycle 15. Cycle 17 specific power distribution data obtained from the neutronics models will be used in the evaluation and analysis of the LFAs in this cycle. (Question 1, Item 3 response, RCTSAI 3220608, Due 10/30/2011)