NL-14-0383, Enclosure 3 to NL-14-0383, Cycle 27 Core Operating Limits Report, Enclosure 4 - LTA Information Letter Eight Nsf Channel Assemblies & Enclosure 5 - LTA Information Letter GNF-Ziron Cladding Material and Water Rod Material..

Enclosure 3 to NL-14-0383, Cycle 27 Core Operating Limits Report, Enclosure 4 - LTA Information Letter Eight Nsf Channel Assemblies & Enclosure 5 - LTA Information Letter GNF-Ziron Cladding Material and Water Rod Material..

ML14094A015
Person / Time
Site:	Hatch
Issue date:	03/28/2014
From:	Southern Nuclear Operating Co
To:	Office of Nuclear Reactor Regulation
References
NL-14-0383
Download: ML14094A015 (38)

Text

Edwin I. Hatch Nuclear Plant - Unit 1 Cycle 27 Core Operating Limits Report, Information Letter on NSF Channel Lead Test Assemblies (LTAs), and Information Letter on GNF-Ziron Cladding Material and Water Rod Material LTAs Enclosure 3 HNP Unit 1 Cycle 27 Version 1 Core Operating Limits Report NON-PROPRIETARY INFORMATION

SOUTHERN NUCLEAR OPERATING COMPANY EDWIN I. HATCH NUCLEAR PLANT Unit 1 Cycle 27 CORE OPERATING LIMITS REPORT Version 1 Southern Nuclear Operating Company Post Office Box 1295 Birmingham, Alabama 35201 Non-ProprietaryInformation

Non-ProprietaryInformation Edwin I. Hatch Nuclear Plant Unit 1 Cycle 27 Core Operating Limits Report TABLE OF CONTENTS Section Title Page 1.0 Introduction 1 2.0 APLHGR Limits 3 3.0 MCPR Operating Limits 6 4.0 LHGR Limits 19 5.0 PBDA Amplitude Setpoint 25 6.0 References 26 i Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report TABLES Table No. Title 1-1 Main Turbine Bypass System Operability 1 1-2 Equipment-Out-of-Service Limitations 2 3-1 Exposure Definitions 8 3-2 MCPR Operating Flexibility Options 9 4-1 LHGR Operating Flexibility Options 20 4-2 LHGR Limit versus Peak Pellet Exposure 20 5-1 OPRM Setpoint 25 ii Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report FIGURES Figure No. Title Page 2-1 Flow-Dependent APLHGR Multiplier 4 (MAPFACF) versus Core Flow 2-2 APLHGR Limit versus Average Planar 5 Exposure 3-1A Power-Dependent MCPR Limit (MCPRp) 10 versus Core Power from 24% to 45% of Rated Core Power 3-1 B Power-Dependent MCPR Limit (MCPRp) 11 versus Core Power from 24% to 45% of Rated Core Power (Main Turbine Bypass System Inoperable) 3-2 Flow-Dependent MCPR Limit (MCPRF) 12 versus Core Flow 3-3A Power-Dependent MCPR Multiplier (Kp) 13 versus Core Power (EOC-RPTSystem in Service and/or Main Turbine Bypass System operable) 3-3B Power-Dependent MCPR Multiplier (Kp) 14 versus Core Power (EOC-RPTSystem Out of Service and Main Turbine Bypass System Inoperable Simultaneously) 3-3C Power-Dependent MCPR Multiplier (Kp) 15 versus Core Power (Main Turbine PressureRegulatorSystem in TLCO 3.3.13.c) 3-4A MCPR Limits versus Average Scram Time 16 (BOC to MOCI) 3-4B MCPR Limits versus Average Scram Time 17 (MOCI to MOC2) iii Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report Figure No. Title Paae 3-4C MCPR Limits versus Average Scram Time 18 (MOC2 to EOC) 4-1 Flow-Dependent LHGR Multiplier 21 (LHGRFACF) versus Core Flow 4-2A Power-Dependent LHGR Multiplier 22 (LHGRFACp) versus Core Power (Main Turbine Bypass System Operable or Inoperable) 4-2B Power-Dependent LHGR Multiplier 23 (LHGRFACp) versus Core Power (Main Turbine Bypass System Operable or Inoperable and Main Turbine Pressure RegulatorSystem in TLCO 3.3.13.c) 4-3 LHGR versus Peak Pellet Exposure 24 iv Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-PropnetaryInformation Limits Report

1.0 INTRODUCTION

The Core Operating Limits Report (COLR) for Plant Hatch Unit 1 Cycle 27 is prepared in accordance with the requirements of Technical Specification 5.6.5. The core operating limits presented herein were developed using NRC-approved methods (References 1 through 6). Results from the reload analyses for the fuel in Unit 1 Cycle 27 are documented in References 3 through 5.

The following core operating limits are included in this report:

a. Average Planar Linear Heat Generation Rate (APLHGR) - Technical Specification 3.2.1

b. Minimum Critical Power Ratio (MCPR) - Technical Specification 3.2.2

c. Linear Heat Generation Rate (LHGR) - Technical Specification 3.2.3 Also included in this report is the maximum allowable scram setpoint for the Period Based Detection Algorithm (PBDA) in the Oscillation Power Range Monitor (OPRM).

Based upon the reload analysis for this cycle, the following operability requirement is defined for Unit I operation.

TABLE 1-1 Main Turbine Bypass System Operability System Operability Requirement Main Turbine Bypass System Operable At least two bypass valves must be (Technical Specification 3.7.7) operable 1 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report From a fuel thermal limits perspective, the following limitations are placed on Unit 1 Cycle 27 operation.

TABLE 1-2 Equipment-Out-of-Service Limitations Equipment I Condition Limitation EOC-RPT Out of Service and Main Turbine Option B scram speeds must be Bypass System Inoperable simultaneously met (in place) at CTP > 45% RTP Main Turbine Pressure Regulator System in Option B scram speeds must be TLCO 3.3.13.c met (in place) at CTP > 45% RTP

• CTP must be < 2000 MWth Single-Loop Operation (SLO)

• Core Flow must be < 56% of Rated NOTE:

The power distribution limits in this report apply to plant operation with all equipment in service, unless otherwise specified.

2 Version 1

Plant Hatch Core Operating Unit I Cycle 27 Non-ProprietaryInformation Limits Report 2.0 APLHGR LIMITS (Technical Specification 3.2.1)

The APLHGR limit for each six inch axial segment of each fuel assembly in the core is the applicable APLHGR limit taken from Figure 2-2 multiplied by the flow-dependent multiplier, MAPFACF, from Figure 2-1.

3 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 3

a.

U.

a.

0.

110 Core Flow (% of Rated)

Operating Conditions F SLO / TLO MAPFACF 30*!_ F* 61 TLO 0.86 61 <F TLO 1.00 30 *- F SLO 0.80 F = Percent of Rated Core Flow FIGURE 2-1 Flow-Dependent APLHGR Multiplier (MAPFACF) versus Core Flow 4 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 14.0 Average Planar APLHGR 13.0 Exposure Limit (GWd/st) (kW/ft) 12.0 0.00 12.82 14.51 12.82 11.0 19.13 12.82 57.61 8.00 63.50 5.00 10.0 E 9.0

-J 8.0 7.0 6.0 5.0 4.0 0.0 5.0 4 10.0 4.

15.0 20.0 25.0 30.0 4 35.0 4 40.0 .

45.0 50.0 55.0 60.0 65.0 70.0 Average Planar Exposure (GWd/st)

FIGURE 2-2 APLHGR Limit versus Average Planar Exposure 5 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 3.0 MCPR OPERATING LIMITS (Technical Specification 3.2.2)

The MCPR operating limit (OLMCPR) is a function of core power, core flow, average scram time, number of operating recirculation loops, EOC-RPT system status, operability of the main turbine bypass system, the status of the main turbine pressure regulator system, and cycle exposure. Cycle exposures are defined in Table 3-1.

With both recirculation pumps in operation (TLO), the OLMCPR is determined as follows:

a. For 24% < power < 45%, the power-dependent MCPR limit, MCPRp, as determined by Table 3-2.

b. For power > 45%, the OLMCPR is the greater of either:

1) The flow-dependent MCPR limit, MCPRF, from Figure 3-2, or

2) The product of the power-dependent multiplier, Kp, and the rated-power OLMCPR, as determined by Table 3-2.

As shown on the figures for absolute MCPR, the OLMCPR with only one recirculation pump in operation (SLO) is equal to the two loop (TLO) OLMCPR plus 0.02.

These limits apply to all modes of operation with feedwater temperature reduction, as well as operation with normal feedwater temperatures.

In Figures 3-4A, 3-4B, and 3-4C, Option A scram time OLMCPRs correspond to c = 1.0, where c is determined from scram time measurements performed in accordance with Technical Specifications Surveillance Requirements 3.1.4.1 and 3.1.4.2. Option B values correspond to c = 0.0. For scram times between Option A and Option B, the rated-power OLMCPR corresponds to r. If t has not been determined, Option A limits must be used.

6 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report The average scram time of the control rods, c, is defined as:

Tave - TB T= 0, or , whichever is greater.

TA - TB where: tA = 1.08 sec (Technical Specification 3.1.4, Table 3.1.4-1, scram time limit to notch 36).

1/2 TB i+1.65 - a ?IN where: . = 0.822 sec (mean scram time used in the transient analysis).

a = 0.018 sec (standard deviation of la).

n = number of surveillance tests performed to date in the cycle.

N, = total number of active rods measured in Technical Specifications Surveillance Requirement 3.1.4.1.

Ni = number of active control rods measured in the ith surveillance test.

Tave - f=

YN, where: Ti = average scram time to notch 36 of all rods in the ith surveillance test.

7 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report TABLE 3-1 Exposure Definitions Exposure Label Cycle Exposure Definition BOC Beginning of Cycle 0 MWd/st Exposure MOC1 First Middle of Cycle EOR - 6062 MWd/st Exposure MOC2 Second Middle of Cycle EOR - 1062 MWd/st Exposure Projected end of rated power EOR End of Rated Exposure with all operable control rods out at rated core flow and rated feedwater temperature EOC End of Cycle Exposure Exposure at cycle shutdown 8 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-Proprietary Information Limits Report TABLE 3-2 MCPR Operating Flexibility Options Rated-power OLMCPRs Cycle Exposure BOC to MOCI Figure 3-4A MOC1 to MOC2 Figure 3-4B MOC2 to EOC Figure 3-4C MCPRP from > 24% to < 45% Power Main Turbine Bypass System Operable* Figure 3-1A Main Turbine Bypass System Inoperable Figure 3-1B Kp for Power > 45% of Rated EOC-RPT Main Turbine Main Turbine Bypass System Pressure Regulator System In Service Operable* System Status Yes Yes TLCO 3.3.13.a or b Figure 3-3A No Yes TLCO 3.3.13.a or b Figure 3-3A Yes No TLCO 3.3.13.a or b Figure 3-3A No No TLCO 3.3.13.a or b Figure 3-3B**

Yes/No Yes/No TLCO 3.3.13.c Figure 3-3C**

At least two bypass valves must be operable

• • Option B scram speeds must be met (in place) at CTP > 45% RTP 9 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 3.0 2.8 i

0.

2 2.6 E

2.4

! 2.2 01 2.0 0.

1.8 1.6 45 Core Power(%of Rated)

MCPRp(TLO) = A + B*P MCPRp(SLO) = MCPRp(TLO) + 0.02 F P A B

<*60 24*< P < 28 4.1235 -0.06673

> 60 24*< P < 28 4.0635 -0.04708

< 60 28*_ P < 45 2.0810 -0.00624

>60 28*< P < 45 2.4861 -0.01067 P = Percent of Rated Core Power F = Percent of Rated Core Flow FIGURE 3-1A Power-Dependent MCPR Limit (MCPRp) versus Core Power from 24% to 45% of Rated Core Power 10 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 4.0 3.8 0.

C 3.4 E 3.2 n 3.0 2.8 2.6 2.4 o 2.2 2.

2.0 1.8 1.6 45 Core Power(%of Rated)

MCPRp(TLO) = A + B*P MCPRp(SLO) = MCPRp(TLO) + 0.02 F P A B

< 60 24 < P < 28 4.3600 -0.07000

>60 24<P<28 6.5876 -0.11670

< 60 28*< P < 45 2.0810 -0.00624

> 60 28 5 P < 45 2.4861 -0.01067 P = Percent of Rated Core Power F = Percent of Rated Core Flow FIGURE 3-1B Power-Dependent MCPR Limit (MCPRp) versus Core Power from 24% to 45% of Rated Core Power (Main Turbine Bypass System Inoperable) 11 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 1.6

- 1.5 0,.

C.,

E "j 1.4 "21.3 0.

1.2 1.1 110 Core Flow (%of Rated)

MCPRF(TLO) = A + B*F MCPRF(SLO) = MCPRF(TLO) + 0.02 Flow A B 30 _ F* 71.160 1.697 -0.00586 71.160 < F 1.280 0.00000 F = Percent of Rated Core Flow FIGURE 3-2 Flow-Dependent MCPR Limit (MCPRF) versus Core Flow 12 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 1.3 1.2 a 1.1 I1 1.0 45 50 55 60 65 70 75 80 85 90 95 100 Core Power (% of Rated)

K-- A + B*P P A B 45*< P < 60 1.6702 -0.00867 60* P 1.3750 -0.00375 P = Percent of Rated Core Power FIGURE 3-3A Power-Dependent MCPR Multiplier (Kp) versus Core Power (EOC-RPTSystem in Service and/orMain Turbine Bypass System operable) 13 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 1.3 1.2 1.

I* 1.1 0) 1.0 45 50 55 60 65 70 75 80 85 90 95 100 Core Power(% of Rated)

KPA + B*P P A B 45 _< P < 60 1.6702 -0.00867 60!_ P < 90 1.3308 -0.00301 90 _ P 1.5961 -0.00596 P = Percent of Rated Core Power FIGURE 3-3B Power-Dependent MCPR Multiplier (Kp) versus Core Power (EOC-RPTSystem Out of Service and Main Turbine Bypass System InoperableSimultaneously) 14 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 1.5 1.4 21.3 r-o.1.2 0

1.1 1.0 70 75 100 Co re Power (% of Rate d)

Kp = A + B*P P A B 45!< P < 70 1.6268 -0.00451 70 < P 2.0367 -0.01037 P = Percent of Rated Core Power FIGURE 3-3C Power-Dependent MCPR Multiplier (Kp) versus Core Power (Main Turbine PressureRegulator System in TLCO 3.3.13.c) 15 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 1.50 1.48 I I I OutofService EOC-RPT Plus 1.46 Turbine Bypass System Inoperable /

1.44 1.42 1.40 E 1.38

-J 0 1.36 1.34 Turbine BypassSystem

[ Inoperable ____ ________

1.32 1.30 1.28 -~If Equipm ent In Se rvice 1.26 1.24 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 Tau OLMCPR(sLo) = OLMCPR(TLO) + 0.02 Operating Conditions OLMCPR(TLO)

EOC-RPT Bypass Valve System t = 0.0 r = 1.0 In Service Operable 1.28 1.30 Out of Service Operable 1.33 1.44 In Service Inoperable 1.30 1.33 Out of Service Inoperable 1.37 1.48 FIGURE 3-4A MCPR Limits versus Average Scram Time (BOC to MOC1) 16 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-PropnetaryInformation Limits Report 1.52 1.50 1.48 EOC-RPT Out of Service Plus Turbine Bypass System Inoperable 1.46 EOC-RPT Out ofServicel 1.44 j 1.42 1.40 Turbline°Byp~aassSystema.../ -

1.38 1.36 All Equipmentin Service 1.34 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 Tau OLMCPR(sLo) = OLMCPR(TLO) + 0.02 Operating Conditions OLMCPR(TLO)

EOC-RPT Bypass Valve System T = 0.0 T= 1.0 In Service Operable 1.34 1.37 Out of Service Operable 1.38 1.49 In Service Inoperable 1.36 1.39 Out of Service Inoperable 1.39 1.50 FIGURE 3-4B MCPR Limits versus Average Scram Time (MOCI to MOC2) 17 Version 1

Plant Hatch Core Operating Unit I Cycle 27 Non-ProprietaryInformation Limits Report

.E 1.0 Tau OLMCPR(sLo) = OLMCPR(TLO) + 0.02 Operating Conditions OLMCPR(TLO)

EOC-RPT Bypass Valve System T = 0.0 T = 1.0 In Service Operable 1.37 1.40 Out of Service Operable 1.42 1.59 In Service Inoperable 1.40 1.43 Out of Service Inoperable 1.45 1.62 FIGURE 3-4C MCPR Limits versus Average Scram Time (MOC2 to EOC) 18 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 4.0 LHGR LIMITS (Technical Specification 3.2.3)

The LHGR limit for each six inch axial segment of each fuel rod in the core is the applicable rated-power, rated-flow LHGR limit taken from Table 4-2 multiplied by the smaller of either:

a. The flow-dependent multiplier, LHGRFACF, from Figure 4-1, or

b. The power-dependent multiplier, LHGRFACp, as determined by Table 4-1.

Table 4-2 shows the exposure-dependent LHGR limits as a function of initial gadolinium concentrations in a six inch segment of a fuel rod. For exposures between the values shown in Table 4-2, the LHGR limit is based on linear interpolation. For illustration purposes, Figure 4-3 shows the LHGR limits for fuel segments with the lowest (UO 2 ) and the highest (U0 2+Gd 2O 3) initial Gd concentration.

19 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-PropnetaryInformation Limits Report TABLE 4-1 LHGR Operating Flexibility Options LHGRFACp Main Turbine Pressure Regulator System Status TLCO 3.3.13.a or b Figure 4-2A TLCO 3.3.13.c Figure 4-2B*

• Option B scram speeds must be met (in place) at CTP > 45% RTP TABLE 4-2 LHGR Limit versus Peak Pellet Exposure Initial Pellet Pellet Pellet Pellet. Pellet Pellet Rod/Section Maximum Exposure Power at Exposure Power at Exposure at Wt-% Gd 20 3 Power Knee I Knee 2 Knee 2 EOL EOL (kWlft) (GWdlst) (kWlft) (GWdlst) (kW/ft) (GWdlst)

Section = Six inch segment of a fuel rod.

EOL = End of Life (maximum licensed pellet exposure) 20 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report U.

C.

0 110 Core Flow (%of Rated)

LHGRFACF = A + B*F Operating Conditions Values of Variables F SLO / TLO A B 30 _ F < 50.70 SLO / TLO 0.4574 0.006758 50.70 _ F < 80.29 TLO 0.4574 0.006758 50.70 _ F SLO 0.8000 0.000000 80.29

• F TLO 1.0000 0.000000 F = Percent of Rated Core Flow FIGURE 4-1 Flow-Dependent LHGR Multiplier (LHGRFACF) versus Core Flow 21 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 1.1 U

C)

I

-j ICI C

CI 0.

C) 0 0.

45 Core Power(%of Rated)

LHGRFACP = A + B*P Operating Conditions Values of Variables P F A B 24*_ P < 28 F > 60 0.17924 0.009670 24*_ P < 28 F* 60 0.10366 0.016741 28* P < 45 All 0.52261 0.003617 45 < P All 0.47760 0.005224 P = Percent of Rated Core Power F = Percent of Rated Core Flow FIGURE 4-2A Power-Dependent LHGR Multiplier (LHGRFACp) versus Core Power (Main Turbine Bypass System Operable or Inoperable) 22 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report 1.1 C,

is 0

Q.

100 Core Power (% of Rate d)

LHGRFACP = A + B*P Operating Conditions Values of Variables P F A B 24*_< P < 28 F > 60 0.17924 0.009670 24*5 P < 28 F* 60 0.10366 0.016741 28< P <70 All 0.52261 0.003617 70 < P All 0.25270 0.007473 P = Percent of Rated Core Power F = Percent of Rated Core Flow FIGURE 4-2B Power-Dependent LHGR Multiplier (LHGRFACp) versus Core Power (Main Turbine Bypass System Operableor Inoperableand Main Turbine PressureRegulatorSystem in TLCO 3.3.13.c) 23 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report Lowest Initial Gd Conc.

Peak Pellet Exposure LHGR (GWd/st) (kW/ft)

Highest Initial Gd Conc.

Peak Pellet Exposure LHGR (GWd/st) (kWlft)

((~

-))

FIGURE 4-3 LHGR versus Peak Pellet Exposure 24 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProppnetaryInformation Limits Report 5.0 PBDA AMPLITUDE SETPOINT The amplitude trip setpoint in the Period Based Detection Algorithm in the OPRM system shall not exceed the value reported in the Table below. This applies to instruments 1C51K615 A, B, C, and D.

TABLE 5-1 OPRM Setpoint OLMCPR OPRM Setpoint

- 1.28 1.15 25 Version 1

Plant Hatch Core Operating Unit 1 Cycle 27 Non-ProprietaryInformation Limits Report

6.0 REFERENCES

1. "General Electric Standard Application for Reactor Fuel," NEDE-2401 1-P-A-19, May 2012, and the US Supplement, NEDE-24011-P-A-19-US, May 2012.

2. GNF letter VSP-SNC-GEN-13-101, "Hatch 1 Cycle 27 SRLR/FBIR 000N0481 RO,"

Vickie S. Perry to S. Hoxie-Key, December 11, 2013.

3. Global Nuclear Fuel Document 000N0481-SRLR, "Supplemental Reload Licensing Report for Edwin I. Hatch Nuclear Power Plant Unit 1, Reload 26 Cycle 27,"

Revision 0, December 2013.

4. Global Nuclear Fuel Document 000N0481-FBIR, "Fuel Bundle Information Report for Edwin I. Hatch Nuclear Power Plant Unit 1, Reload 26 Cycle 27," Revision 0, December 2013.

5. SNC Nuclear Fuel Document NF-13-171, "Hatch-1 Cycle 27 Reload Licensing Analysis Report," Version 1, December 2013.

6. GNF Document NEDC-32868P, "GE14 Compliance with Amendment 22 of NEDE-24011-P-A (GESTAR II)," Rev. 5, May 2013.

26 Version 1

Edwin I. Hatch Nuclear Plant - Unit 1 Cycle 27 Core Operating Limits Report, Information Letter on NSF Channel Lead Test Assemblies (LTAs), and Information Letter on GNF-Ziron Cladding Material and Water Rod Material LTAs Enclosure 4 LTA Information Letter Eight NSF Channel Assemblies to NL-14-0383 LTA Information Letter Eight NSF Channel Assemblies Description of Lead Test Assemblies Eight LTAs were loaded into the Plant Hatch Unit 1 at the beginning of Cycle 27.

The GNF supplied assemblies contain standard GE14 components and fuel with the exception of the channel. The channels were manufactured with a distortion-resistant material known as NSF. The term NSF reflects the presence of Niobium (Nb), Tin (Sn) and Iron (Fe) as the primary alloying metals combined with Zirconium. Similar Zirconium-Niobium alloys are commonly used in PWR and Russian plants, but not commercially used in BWRs.

The NSF alloy is resistant to channel bowing and has a much lower sensitivity to cold-work compared to Zircaloy. The mechanical properties of NSF are similar to the standard Zircaloys, and are considered adequate for reactor service.

Corrosion performance of NSF is adequate based on visual and hot-cell examinations after six years of operation.

The surface condition of these NSF channels has been modified compared to the previous NSF channels irradiated in Hatch 2. The NSF channels inserted in Plant Hatch Unit 1 Cycle 27 have a pre-oxidized surface condition similar to the pre-oxidized surface condition that was standard on Zircaloy-4 channels prior to 1990. The previously discharged NSF channels and current operating NSF channels in Plant Hatch Unit 2 had the standard etched-surface condition.

Applicability of GESTAR GNF has reviewed the properties of the NSF channels relative to the properties of Zircaloy-2 and Zircaloy-4 in the context of required functions, including safety, of fuel channels as described in GESTAR and the relevant LTRs. GNF has concluded that the use of NSF as a channel material meets the approved criteria of GESTAR and NRC-approved methods are applicable. Therefore, NSF channels may be used in an LTA.

Objectives of LTA Program The objectives of this program are to expand the experience base on Pre-Ox NSF channels and to confirm that the corrosion performance of the pre-oxidized surface condition is equivalent to the standard etched-surface condition.

Inspection results of NSF channels currently in operation in other domestic BWRs are expected to be evaluated to confirm the expected lower irradiation growth characteristics of this material as well as validate adequate resistance to shadow corrosion-induced bow and bulge. Standard analyses will be performed to assure that the safety and licensing bases are maintained.

Outline of Measurements Corrosion performance will be evaluated after discharge.

E4-1 to NL-14-0383 LTA Information Letter Eight NSF Channel Assemblies

REFERENCES:

1. NEDE-2401 1-P-A-20 & NEDE-2401 1-P-A-20-US, General Electric StandardApplication for Reactor Fuel & Supplement for United States, (GESTAR II, Licensing Topical Report).

2. Letter from T.A. Ippolito (NRC) to R.E. Engel (GE), Lead Test Assembly Licensing, September 23, 1981 E4-2

Edwin I. Hatch Nuclear Plant - Unit 1 Cycle 27 Core Operating Limits Report, Information Letter on NSF Channel Lead Test Assemblies (LTAs), and Information Letter on GNF-Ziron Cladding Material and Water Rod Material LTAs Enclosure 5 LTA Information Letter GNF-Ziron Cladding Material and Water Rod Material Assembly to NL-14-0383 LTA Information Letter GNF-Ziron Cladding Material and Water Rod Material Assembly Description of Lead Test Assemblies Two lead test assemblies (LTAs), with selected fuel rods (29 rod in each assembly) fabricated from GNF-Ziron cladding material were loaded into Plant Hatch Unit 2 during Cycle 21, with planned operation through Cycles 22 and 23.

The LTAs completed operation in Plant Hatch Unit 2 during Cycles 21 and 22, but these LTAs were not in operation during Cycle 23. SNC is irradiating one of these LTAs in Plant Hatch Unit 1 during Cycle 27. Due to issues unrelated to the cladding material inspection results, the other LTA is not being used during Unit 1 Cycle 27. These GNF-supplied fuel assemblies are standard GE14 fuel assemblies with the exception of the cladding material and water rod material.

GNF-Ziron is a zirconium-based alloy with composition very similar to the industry standard Zircaloy-2 but with increased iron content. The dimensions and processing of all assembly components are identical to the standard GE14 assemblies.

GE14 fuel is licensed according to criteria and requirements specified in GESTAR II (General Electric Standard Application For Reactor Fuel, NEDE-2401 1-P-A), as reported in the GE14 compliance report (GE14 Compliance With Amendment 22 of NEDE- 24011-P-A, NEDC-32868P, Rev. 5). The GE14 compliance report states that the GE14 fuel cladding and water rods are made of Zircaloy-2.

Because the composition of GNF-Ziron falls outside of the ASTM-specification ranges for Zircaloy-2, the current GE14 compliance report does not cover the use of GNF-Ziron for reload applications. Specific approval from the NRC on the use of GNF-Ziron as cladding material is therefore required before the alloy can be deployed in reload quantities; in addition, an amendment to the GEl4 compliance report will be needed. GNF has submitted a Licensing Topical Report (LTR)

(Reference 1) to the NRC to seek approval for the use of GNF-Ziron as cladding material. The LTR has not yet been approved by the NRC. In the absence of specific approval from the NRC, Reference 2 discusses how LTAs may be loaded provided LTAs are analyzed with approved methods. However, 10 CFR Part 50, Section 50.46 and Appendix K specifically address cladding material made from Zircaloy or Zirlo. As GNF-Ziron is not a Zircaloy, exemptions to the requirements of 10 CFR Part 50, Section 50.46 and Appendix K were submitted to the NRC in 2008 (Reference 3) supporting the LTAs operation starting in 2009 in Plant Hatch Unit 2. Accordingly, two GE14 GNF-Ziron LTAs were loaded into Unit 2 per provisions in 10 CFR Part 50, Section 50.59 and were irradiated in Cycles 21 and

22. Subsequently, in 2013, an additional exemption request was submitted (Reference 4) to support further irradiation of these LTAs for one or more additional cycles in Unit 1 or Unit 2 of the Edwin I. Hatch Nuclear Plant.

A more detailed description of GNF-Ziron material, including its key properties, is given in both the submitted LTR (Reference 1) and SNC's first exemption request submitted in 2008 (Reference 3). A discussion on the applicability of approved methods to GNF-Ziron cladding is given in References 1 and 5. As discussed in Reference 1, GNF's approved methods remain applicable to, and unaffected by, incorporation of GNF-Ziron. In support of the Reference 4 application for exemption from 10 CFR Part 50, Section 50.46 and Appendix K requirements to use Zircaloy fuel cladding, information on the high temperature oxidation behavior of GNF-Ziron pertaining to postulated loss-of coolant accident (LOCA)

E5-1 to NL-14-0383 LTA Information Letter GNF-Ziron Cladding Material and Water Rod Material Assembly considerations are provided in Reference 5. The exemption request was approved by the NRC on February 4, 2014 (Reference 6).

Objectives of LTA Program The objective of the LTA program at Plant Hatch is to obtain operational experience with GNF-Ziron cladding and water rod material. The performance of GNF-Ziron under normal operating conditions is expected to be similar to that of Zircaloy-2. The LTA program will provide confirmation on the GNF-Ziron performance.

Outline of Measurements Since obtaining operational experience with GNF-Ziron is the main objective of the Plant Hatch LTA program, poolside inspections (e.g., visual, eddy current liftoff, and profilometry) will be conducted on selected rods.

References

1. "Application of GNF-Ziron to GNF Fuel Designs," NEDC-33353P and NEDO-33353, December 22, 2010, MFN 10-358.

2. NRC Letter, "Lead Test Assembly Licensing," T. A. Ippolito (NRC) to R. E.

Engel, September 23,1981.

3. SNC Letter to NRC, "Edwin I. Hatch Nuclear Plant - Unit 2 Submittal of Additional Information to Support Proposed Exemption to 10 CFR 50.46 and 10 CFR 50 Appendix K to Allow Ziron Fuel Cladding", September 22, 2008, ML082681156.

4. SNC Letter NL-13-0402, "Edwin I. Hatch Nuclear Plant Proposed Exemption to 10 CFR 50.46 and 10 CFR 50 Appendix K to Allow GNF-Ziron Fuel Cladding," C. R. Pierce to USNRC, April 23, 2013.

5. 'Technical Basis Supporting GNF-Ziron Lead Test Assembly Introduction into the Hatch Nuclear Plant" in License support letter for GNF-Ziron LTA at Hatch, eDRFsection 0000-0079-7396, as attachment in Reference 3.

6. NRC Letter, "Edwin I. Hatch Nuclear Plant, Unit Nos 1 and 2, Exemption from the Requirements of 10 CFR Part 50, Section 50.46, and Appendix K (TAC Nos. MF1479 and MF1480)", R. E. Martin to C. R. Pierce, February 4, 2014, ML13354B755.

E5-2