ML25258A105
| ML25258A105 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 09/15/2025 |
| From: | Hardy J Entergy Operations |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| GNRO2025-00024 | |
| Download: ML25258A105 (1) | |
Text
~ entergy G N RO2025-00024 September 15, 2025 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Entergy Operations, Inc.
P.O. Box 756 Port Gibson, Mississippi 39150 Jeffery Hardy Manager Regulatory Assurance Grand Gulf Nuclear Station Tel: 802-380-5124 GGNS TS 5.6.5
SUBJECT:
Grand Gulf Nuclear Station (GGNS) Core Operating Limits Report (COLR) Cycle 25, Revision 1 Grand Gulf Nuclear Station, Unit 1 Docket No. 50-416 License No. NPF-29 In accordance with 10 CFR 50.36 and GGNS Technical Specification Section 5.6.5.d, GGNS is required to provide to the Nuclear Regulatory Commission any updates to the COLR.
Revision 1 of the GGNS Cycle 25 COLR is attached to this letter.
There are no commitments contained in this submittal. If you have any questions or need additional information, please contact me at 802-380-5124.
Sincerely, C)AW}
JH/ram
Attachment:
Core Operating Limits Report (COLR) Cycle 25, Revision 1
GNRO2025-00024 Page 2 of 2 cc:
NRG Senior Resident Inspector Grand Gulf Nuclear Station Port Gibson, MS 39150 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001
Grand Gulf Nuclear Station Core Operating Limits Report Cycle 25 Revision 1
CORE OPERATING LIMITS REPORT REASON FOR REVISION Revision 0:
The Cycle 25 core operating limits are updated to provide cycle-specific MCPR and LHGRFAC multiplier values for the GNF3 fuel in Cycle 25. Figure 1-1 provides the APLHGR limits for the GNF3 fuel type. Figures 2-1 through 2-6 are updated with new MCPR limits and Figures 3-1 through 3-3 are updated with new LHGRFAC limits.
No other core operating limits are changed.
These limits are based on a core power of 4408 MWt.
Revision 1:
The Cycle 25 core operating limits are updated due to a higher OLMCPR being required for the last sequence, referred to as SEQ#7 or SEQ A2-3 (see CR-GGN-2025-01036). Table 7 is updated to include the split in the OLMCPR limits at SEQ#7 (Option A OLMCPRs are unchanged). MCPRp Figures 2-1 through 2-3 are split into BOC to MOC, MOC to SEQ A2-3, and SEQ A2-3 to EOC to incorporate the higher OLMCPR in the last sequence (SEQ A2-3) of Cycle 25.
CORE OPERATING LIMITS REPORT TABLE OF CONTENTS 1.0 PURPOSE 4
2.0 SCOPE 4
3.0 REFERENCES
5 3.1 Current Cycle References 5
4.0 DEFINITIONS 7
5.0 GENERAL REQUIREMENTS 9
5.1 Averaqe Planar Linear Heat Generation Rates 9
5.2 Minimum Critical Power Ratio 9
- 5. 3 Linear Heat Generation Rate 10 5.4 Stability 10
- 5. 5 Applicability 11 5.6 Limitations and Conditions 11 Table 1 OPRM Upscale CDA Amplitude Discriminator 12 Setpoint Table 2 BSP Endpoints for Normal Feedwater Temperature 12 Table 3 BSP Endpoints for Reduced Feedwater 12 Temperature Table 4 ABSP Setpoints for the Scram Region 12 Table 5 Margin to Thermal Overpower and Mechanical 12 Overpower Limits Table 6 Application Conditions 13 Table 7 Rated OLMCPR Summary Table 13 Figure(s) 1 APLHGR Operating Limits 14 Figure(s) 2 MCPR Operating Limits 15 Figure(s) 3 LHGR Operating Limits 29 Figure 4 Backup Stability Protection Region Boundaries 31 for Normal Feedwater Temoerature Figure 5 Backup Stability Protection Region Boundaries 32 for Reduced Feedwater Temperature COLR Page 3 LBDCR 2025-0027
CORE OPERATING LIMITS REPORT 1.0 PURPOSE The COLR is controlled as a License Basis Document and revised accordingly for each fuel cycle or remaining portion of a fuel cycle.
Any revisions to the C0LR must be submitted to the NRC for information as required by Tech Spec 5.6.5 and tracked by Licensing Commitment 29132.
This C0LR reports the Cycle 25 core operating limits and stability setpoint confirmation and regions.
2.0 SCOPE As defined in Technical Specification 1.1, the C0LR is the GGNS document that provides the core operating limits for the current fuel cycle.
This document is prepared in accordance with Technical Specification 5.6.5 for each reload cycle using NRC-approved analytical methods.
The Cycle 25 core operating and stability limits included in this report are:
the Average Planar Linear Heat Generation Rate (APLHGR),
the Minimum Critical Power Ratio (MCPR) (including E0C-RPT inoperable),
the Linear Heat Generation Rate (LHGR) limit, and the DSS-CD stability setpoint confirmation and regions.
CORE OPERATING LIMITS REPORT
3.0 REFERENCES
This section contains the cycle-specific references used in the safety analysis of Grand Gulf Cycle 25.
Methodology references are documented in Technical Specification 5.6.Sb.
3.1 Current Cycle References 3.1.1 ECH-NE-24-00003 Revision 0, Supplemental Reload Licensing Report for Grand Gulf-1 Reload 24 Cycle 25, December 2023.
3.1.2 GNF007N0437 Revision 0, Nuclear Design Report for Grand Gulf Nuclear Station Cycle 25, September 2023.
3.1.3 ECH-NE-24-00002 Revision 0, Fuel Bundle Information Report for Grand Gulf-1 Reload 24 Cycle 25, December 2023.
3.1.4 NEDC-32910P, Revision 1, Grand Gulf Nuclear Station SAFER/GESTR-LOCA Accident Analysis With Relaxed ECCS Parameters, October 1999 (GEXI-1999-00174).
3.1.5 GGNS-NE-12-00022 Revision 1, Grand Gulf Nuclear Station MELLLA+ Task T0407, ECCS-LOCA Performance, October 2019.
3.1.6 SC 21-04 Revision 3, Fuel Support Side Entry Orifice Meta-Stable Flow for 2 Beam Locations in the BWR/6 Reactors, February 2024.
3.1.7 NEDC-33173P-A, Revision 5, Applicability of GE Methods to Expanded Operating Domains (with Supplements SP-A Rev. 1, and 6P-A Rev. 1), October 2019.
3.1.8 NEDC-33006P-A, Revision 3, GE BWR Maximum Extended Load Line Limit Analysis Plus, June 2009.
3.1.9 GGNS-SA-21-00002, Revision O (GEH 0000-0158-7807-Rl), Grand Gulf Nuclear Station PRNM System DSS-CD Settings, April 2020.
3.1.10 ECH-NE-20-00006 Revision 0, GNF3 Fuel Design Cycle-Independent Analyses for Grand Gulf Nuclear Station, February 2020.
3.1.11 GGNS-SA-19-00001 Revision O Grand Gulf Nuclear Station GNF3 ECCS-LOCA Evaluation Revision 1, October 2019.
3.1.12 GEH-GGNS-AEP-632, GGNS MELLLA+ Final DSS-CD Settings Report, October 23, 2013.
3.1.13 NEDE-24011-P-A-31, General Electric Standard Application for Reactor Fuel (GESTAR-II). November 2020, (KGO-ENO-GEN-21-039).
3.1.14 ECH-NE-21-00025 Rev. 1, Grand Gulf Nuclear Station TRACG Implementation for Reload Transient Analysis (T1309), December 2023.
CORE OPERATING LIMITS REPORT 3.1.15 NED0-33612-A, Revision 0, Safety Analysis Report for GGNS Maximum Extended Load Line Limit Analysis Plus, September 2013.
3.1.16 NEDC-33879P, Revision 4, GNF3 Generic Compliance with NEDE-24011-P-A (GESTAR II), August 2020.
3.1.17 NEDC-33880P, Revision 1, GEXL21 Correlation for GNF3 Fuel, November 2017 (KGO-ENO-GEN-20-031).
3.1.18 NEDC-33840P-A, Revision 1, The PRIME Model for Transient Analysis of Fuel Rod Thermal - Mechanical Performance, August 2017.
3.1.19 GGNS-NE-10-00076, Revision O (GEH 0000-0121-1122-RO), GGNS EPU Option B Scram Times, September 2010.
3.1.20 GNF010N0134, Revision 0, Grand Gulf Cycle 25 RWE Evaluation for Evolutions in the RWE Analysis Process, June 2025.
3.1.21 ECH-NE-24-00007, Revision 0, Grand Gulf Cycle 25 Cycle Management Report.
Screening of Pellet-Cladding Interaction (PCI) Risk Factors. and Shutdown Margin (SOM) Analysis Accounting for SC 20-06 & SC 23-02, March 2025.
CORE OPERATING LIMITS REPORT 4.0 DEFINITIONS 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 4.12 4.13 4.14 4.15 4.16 4.17 Average Planar Linear Heat Generation Rate (APLHGR) - the APLHGR shall be applicable to a specific planar height and is equal to the sum of the linear heat generation rates for all the fuel rods in the specified bundle at the specified height divided by the number of fuel rods in the fuel bundle at the specified height.
Average Planar Exposure - the Average Planar Exposure shall be applicable to a specific planar height and is equal to the sum of the exposure of all the fuel rods in the specified bundle at the specified height divided by the number of fuel rods in the fuel bundle at the specified height.
Critical Power Ratio (CPR) - the ratio of that power in the assembly, which is calculated by application of the fuel vendor's appropriate boiling correlation, to cause some point in the assembly to experience boiling transition, divided by the actual assembly operating power.
Core Operating Limits Report (COLR) - The Grand Gulf Nuclear Station specific document that provides core operating limits for the current reload cycle in accordance with Technical Specification 5.6.5.
Linear Heat Generation Rate (LHGR) - the LHGR shall be the heat generation per unit length of fuel rod. It is the integral of the heat flux over the heat transfer area associated with the unit length.
Minimum Critical Power Ratio (MCPR) - the MCPR shall be the smallest CPR which exists in the core.
MCPR Safety Limit - cycle specific SLMCPR, known as MCP~9-~, is the minimum value of the CPR at which the fuel could be operated to ensure that 99.9%
percent of the fuel in the core is not susceptible to the boiling transition.
Oscillation Power Range Monitor (OPRM) - Provides automatic detection and suppression of reactor core thermal ~hydraulic instabilities through monitoring neutron flux changes.
Backup Stability Protection (BSP) Boundary - Defines the operation domain where potential instability events can be effectively addressed by specific operator action. Region of the power and flow operating domain that is not expected to be susceptible to instability events associated with a high initial growth rate.
Backup Stability Protection (BSP) Scram Region - The area of the core power and flow operating domain where the reactor is susceptible to reactor instabilities under conditions exceeding the licensing basis of the current reactor system.
An immediate manual scram is required upon entry.
Backup Stability Protection (BSP) Controlled Entry Region - The area of the core power and flow operating domain where the reactor is susceptible to reactor instabilities.
Compliance with at least one alternate stability control is required upon entry.
Automated Backup Stability Protection (ABSP) Scram Region - An automated reactor scram region that bounds the BSP Scram Region and is initiated by the APRM flow-biased scram setpoint upon entry.
End of Rated (EOR) - The Cycle exposure corresponding to all rods out, 100%
power, 100% flow, and normal feedwater temperature [3.1.1].
Middle of Cycle (MOC) - The Cycle 25 MOC Core Average Exposure (CAE) is MOC= EOR-4,000 MWd/ST [3.1.1].
End of Cycle (EOC) - The Cycle 25 EOC CAE is 33,334 MWd/ST [3.1.2].
Maximum Extended Load Line Limit Analysis Plus (MELLLA+) - The GGNS MELLLA+
operating domain is depicted in Figure 4.
Maximum Number of OPRM Cells Along an Instability Symmetry Axis (M~) - An OPRM configuration constant representing maximum number of OPRM cells along an instability symmetry axis. It is used to calculate the number of COLR Page 7 LBDCR 2025-0027
CORE OPERATING LIMITS REPORT unresponsive OPRM cells. Per [3.1.12] the GGNS specific value is five CM~ = 5).
4.18 Application Conditions - The combination of equipment out of service conditions for which LHGRFAC and MCPR limits are determined [3.1.1]. The Application Conditions are specified in Table 6.
4.19 MCPRgs/95 Safety Limit - Cycle-independent Technical Specification (TS) 2.1.1 SLMCPR, ensures there is a 95 percent probability at a 95 percent confidence level that no fuel rods will be susceptible to transition boiling.
4.20 SEQ#? (SEQ A2-3) - The seventh sequence is the third A2 sequence. The SEQ#?
(also referred to as SEQ A2-3) early start exposure is 13,288 tv'rvvd/ST
[3.1.21].
CORE OPERATING LIMITS REPORT 5.0 GENERAL REQUIREMENTS 5.1 Average Planar Linear Heat Generation Rates Consistent with Technical Specification 3.2.1, all APLHGRs shall not exceed the fuel type and exposure-dependent limits reported in Figure 1-1 [3.1.1].
5.2 Minimum Critical Power Ratio For Cycle 2 5, the cycl e-speci fi c MCPR Safety Limit (MCPR99.9%), is 1.12 for Two Loop Operation (TLO), and 1.12 for Single Loop Operation (SLO) [3.1.1].
GEH Safety Communication (SC) 21-04 [3.1.6] identifies a metastable flow condition that may exist in a BWR/6 in core locations fed by a side entry orifice adjacent to two core support cross beams. The vendor has been unable to determine the frequency of occurrence of this flow condition, if any. This flow condition results in a higher loss coefficient and lower CPR (applied as higher MCPR limits). To be conservative, it is assumed this condition always exists, so an MCPR penalty is always applied. All power-dependent MCPR limits in the COLR Tables and Figures apply the penalty recommended by SC 21-04 Rev. 3.
Consistent with Technical Specification 3.2.2, the MCPR shall be equal to or greater than the limits reported in Figure(s) 2 as functions of power, flow, exposure, and sc ram speed [3.1.1, 3.1.10, 3.1.19, 3.1.20]. For operation at powers
~35.4%, the power-dependent MCPR shall be determined based on scram time surveillance data as follows. [3.1.19]
- 1) If the average scram time (TAvE) satisfies the following:
TAVE ::;TB,
then the power dependent MCPR shall be equal to or greater than the Option B limits reported in Figure(s) 2 as a function of exposure.
- 2)
If the average scram time then the power-dependent MCPR shall be equal to or greater than the Tau 0.2 limits reported in Figure(s) 2 as a function of exposure,
- 3)
If the average scram time TAvE >Ts and -r> 0.2,
then the power-dependent MCPR shall be equal to or greate r than the Option A limits reported in Figure(s) 2 as a function of exposure.
In the above equations:
TAVE = average scram time to the 20% insert ion position as calculated by equation 1 of Reference 3.1.19,
CORE OPERATING LIMITS REPORT r 8 adjusted analysis mean scram time for 20% insertion as calculated by equation 3 of Reference 3.1.19 and where r A the technical specification limit on core average scram time to the 20 percent insertion position (0.503 seconds).
The limits determined above support operation with Turbine Bypass Valves Out of Service as described in Technical Specification 3.7.7. Additional MCPR operating limits are provided to support operation with EOC-RPT inoperable as described in Technical Specification 3.3.4.1.
Rated Operating Limit MCPR values (equipment in service, 100% power, OLMCPR's) are provided in Table 7. The power-dependent MCPR results in Figures 2-1 through 2-5 include the SC 21-04 Rev. 3 [3.1.6] penalties. The SC21-04 Rev. 3 penalties do not need to be applied to flow-dependent MCPR results.
5.3 Linear Heat Generation Rate Consistent with Technical Specification 3.2.3, the LHGRs for any GNF3 fuel rod at any axial location shall not exceed the nodal exposure-dependent limits reported in Reference 3.1.3 (by reference reported in [3.1.16]) multiplied by the smaller of either the power-dependent or flow-dependent LHGR factors reported in Figures 3-1 and 3-2, and Figures 3-3, respectively [3.1.1].
The limits determined above support operation with Turbine Bypass Valves Out of Service as described in Technical Specification 3.7.7.
5.4 Stability The OPRM Upscale Confirmation Density Algorithm (CDA) Amplitude Discriminator setpoint is reported in Table 1.
The Backup Stability Protection (BSP) regions boundaries are reported in Figures 4 and 5 [3.1.1]. BSP measures support operation with the OPRM upscale trip function inoperable as described in Technical Specification 3.3.1.1 Condition J. The endpoints for the BSP region boundaries are provided for normal (NFWT) and reduced (RFWT) feedwater temperature operations in Tables 2 and 3, respectively. Figures 4 and 5 depict the BSP region boundaries for NFWT and RFWT operations. Note that Figures 4 and 5 also depict the MELLLA+ and MELLLA domains, consistent with feedwater temperature operating limitations.
The ABSP APRM Simulated Thermal Power (STP) setpoints associated with the ABSP Scram Region are provided in Table 4. The ABSP setpoints are applicable to TLO and SLO, and to both normal and reduced feedwater temperature operations.
The BSP Boundary and Manual BSP region boundaries for normal feedwater temperature operations are valid for reductions in normal feedwater temperature as much as (and including) -10.0 °F. [3.1.1].
CORE OPERATING LIMITS REPORT 5.5 Applicability The following core operating limits are applicable for operation in the Maximum Extended Operating Domain (MEOD), with Feedwater Heaters Out of Service (FWHOOS),
Turbine Bypass Out of Service (TBVOOS), EOC-RPT inoperable, and Pressure Regulator Out of Service (PROOS).
For operation with one of the previous conditions mentioned, the alternate MCPR limits described in Section 5.2 above must be implemented. Table 6 provides an applicability condition list of events related to the Figures. For SLO, the following additional requirements must be satisfied.
- 1. THE APLHGRs shall not exceed the exposure-dependent limits determined in accordance with Section 5.1 [3.1.1].
2. THE LHGRs shall not exceed the smaller of the nodal exposure-dependent limits determined in accordance with Section 5.3 above or the nodal exposure-dependent limits reported in Reference 3.1.3.
- 3. The MCPR shall be equal to or greater than the limits determined in accordance with Section 5.2 above increased by 0.02. SLO MCPR operating limits are displayed in Figures 2-1 through 2-3 "D" & "E" and "F", Figures 2-1 4 through 2-5 "C" & "D" and Figure 2-6 "B" [3.1.1].
5.6 Limitations and Conditions As required by Limitation and Condition 9.10/9.ll of licensing topical report NEDC-33173P-A [3.1.7], the limiting Thermal and Mechanical Overpower results are reported in Table 5. The results are summarized as a percent margin to both of these limits.
The results are confirmed to meet the required 10% margin to the design limits [3.1.1, 3.1.20].
As required by Limitation and Condition 12.10.b of licensing topical report NEDC-33006P-A [3.1.8], the off-rated limits assumed in the ECCS-LOCA analyses are confirmed to be consistent with the off-rated LHGR multipliers provided Figures 3-1 through 3-3. These off-rated LHGR multipliers provide adequate protection for MELLLA+ operation.
As required by Limitation and Condition 12.5.c of licensing topical report NEDC-33006P-A [3.1.8], the plant specific power/flow map specifying the GGNS licensed MELLLA+ operating domain is included as Figure 4.
As required by Limitation and Condition 12.5.b of licensing topical report NEDC-33006P-A [3.1.8], operation with Feedwater Heaters Out of Service (FWHOOS) is prohibited while in the MELLLA+ operating domain [3.1.1]. In addition, as required by Limitation and Condition 12.5.a of licensing topical report NEDC-33006P-A
[3.1.8], and described in GGNS TS 3.4.1 LCO, SLO is prohibited in the MELLLA+
operating domain [3.1.1].Therefore, operations with RFWT and/or SLO must adhere to the operating domain shown in Figure 5.
Endpoint Al Bl CORE OPERATING LIMITS REPORT Table 1 OPRM Upscale CDA Amplitude Discriminator Setpoint Amplitude Discriminator Trip 1.10 Table 2 BSP Endpoints for Normal Feedwater Temperature Power(%)
Flow(%)
Definition
- 72. 3 44.2 Scram Region Boundary, 34.1 25.2 Scram Reqion Boundary, HFCL NCL A2 67.3 50.0 Controlled Entry Reqion Boundary, HFCL B2 26.4 24.4 Controlled Entry Region Boundary, NCL Table 3 BSP Endpoints for Reduced Feedwater Temperature Endpoint Power(%)
Flow(%)
Definition Al' 66.9 49.5 Scram Region Boundary, HFCL Bl' 28.6 24.6 Scram Reqion Boundary, NCL A2' 68.3
- 51. 2 Controlled Entry Reqion Boundary, HFCL B2' 26.4 24.4 Controlled Entry Region Boundary, NCL Table 4 ABSP Setpoints for the Scram Region Parameter Symbol Value Slope of ABSP APRM fl ow-biased trip linear segment mTRIP
- 0. 77 ABSP APRM flow-biased trip setpoint power intercept.
PssP-TRIP
- 31. 0% RTP 1 Constant Power Line for Trip from zero Drive Flow to Flow Breakpoint.
ABSP APRM flow-biased trip setpoint drive flow WssP-TRIP
- 39. 0% RDF 2
intercept. Constant Flow Line for Trip.
Flow Breakpoint value WssP-BREAK
- 7. 6% RDF 2
- 1. RTP - Rated Thermal Power
- 2. RDF - Recirculation Dri ve Flow Table 5 Margin to Thermal Overpower and Mechanical Overpower Limits Criteria GNF3 Thermal Overpower Margin 39.83%
Mechanical Overpower Margin 47.65%
Application Condition 1
2 3
4 5
6 7
8 COLR Page 13 CORE OPERATING LIMITS REPORT Application Condition 1
2 3
4 5
6 7
8 Table 6 Application Conditions FWH 005 EOC-RPT PR 005 X
X X
X X
X X
X X
X X
X Table 7 Rated OLMCPR Surrrnary Table TBV 005 X
X X
X X
X X
X GNF3 OPT GNF3 OPT GNF3 OPT GNF3 OPT GNF3 OPT GNF3 OPT A BOC-MOC B BOC-MOC A MOC-B MOC-A SEQ#?-
B SEQ#?-
SEQ#?
SEQ#?
EOC EOC
- 1. 37
- 1. 30
- 1. 38
- 1. 30
- 1. 38
- 1. 32
- 1. 37
- 1. 30
- 1. 38
- 1. 30
- 1. 38
- 1. 32
- 1. 37
- 1. 30
- 1. 39
- 1. 31
- 1. 39
- 1. 32
- 1. 37
- 1. 30
- 1. 39
- 1. 31
- 1. 39
- 1. 32
- 1. 38
- 1. 38 1.42 1.42 1.42 1.42
- 1. 38
- 1. 38 1.46 1.46 1.46 1.46
- 1. 38
- 1. 38 1.42 1.42 1.42 1.42
- 1. 38
- 1. 38 1.46 1.46 1.46 1.46 LBDCR 2025-0027
15 0.00, 14.36 14 13 12 i° 11
- t
~ 10
~
C) 9
- x:
..J 0.. i 8
7 6
5 4
0 COLR Page 14 10 CORE OPERATING LIMITS REPORT 20 30 40 Average Planar Exposure (GWd/ST)
Figure 1~1 50 GNF3 Maximum Average Planar Linear Heat Generation Rate Note: Actual Limits described in Sections 5.1 and 5.5 63.50, 6.00 60 70 LBDCR 2025-0027
2.2 2.1 2.0 1.9 1.8 0:: 1.7
?[ 1.6
- 0.
u
- e 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8 0:: 1.7
?[ 1.6
- 0.
u
- e 1.5 1.4 1.3 1.2 1.1 1.0 0
COLR Page 15 CORE OPERATING LIMITS REPORT
~ 50% Core Flow 21.8, 2.08
/
21.8, 1.97
< 50% Core Flow /
35.4, 1.90 Option A 10 21.8, 2.08 21.8, 1.97 20 35.4, 1.68 35.4, 1.62 35.4, 1.60 30
- 40. 1.68 40, 1.60 1-:~===:~::::::::;;;J 70, 1.43 50, 1.51/
so. 1.53 70, 1.46 70, 1.38 Option B 70, 1.36 40 50 60 70 80 Core Power(% Rated)
Flgure2-1A Cycle 25 Power-Dependent MCPR Limits, EIS BOC to MOC, n.o
~ 50% Core Flow
< 50% Core Flow/
Option A
/
10.rn 35.4, 1.69 35.4, 1.62 35.4, 1.60 Tau =0.2 90 100 Tau =0.2 40, 1.62 40, 1.60 70, 1.44 85, 1.43 50, 1.1/
50, 1.53 70, 1.46 85, 1.37
'~~,:~~~.t~ =: =~ =~ =: =_=~ =\\.'. =~=~-,,11~~---::--
100, 1.38 100, 1.32 100. 1.30 10 20 30 Option B 70, 1.38 40 50 60 Core Power (% Rated)
Figure 2-18 70, 1.44 70, 136 70 Cycle 25 Power-Dependent MCPR Limits, EIS MOC to SEQ A2-3, n.o 85, 1.3S 80 90 100 LBDCR 2025-0027
2.2 2.1 2.0 1.9 1.8 a: 1.7 ix 1.6 Q. u
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8 a: 1.7 ix 1.6 Q. u
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
COLR Page 16 CORE OPERATING LIMITS REPORT 21.8, 2.08 21.8, 1.97
< 50% Core Flow /
35.4, 1.69 35.4, f.64 35.4, 1.62
- . 50% Core Flow 35.4, 1.90 Option A I "-*~
40, 1.64 50, f.1/
70, f.44 85, 1.43 10 20 21.8, 2.10 21.8, 1.99 30 40, 1.62 50, 1.55 70, 1.48 Optton B 70, 1.40 40 50 60 Core Power (% Rated)
Figure 2-1c 70, 1.<IS 70, 1.38 70 Cycle 25 Power-Dependent MCPR Limits, EIS SEQ A2-3 to EOC, TLO
< 50% Core Flow /
35.4, 1.92 10 20 35.4, 1.70 3S.4, 1.64 35.4, 1.62 30 Option B 40 50 60 Core Power (% Rated)
Flgure2-1D 70 Cycle 25 Power-Dependent MCPR Limits, EIS BOC to MOC, SLO as. 1_39 85, 1.37 80 90 80 90 Tau= 0.2 100. 1.33 100, 1.34 100, 1.32 100 100 LBDCR 2025-0027
2.2 2.1 2.0 1.9 1.8 a: 1.7 ix 1.6
- 0.
~ 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8 a: 1.7 ix 1.6 Q.
V
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
COLR Page 17 CORE OPERATING LIMITS REPORT
~ 50% Core Flow 21.8, 2.10
/
21.8. 1.99
< 50% Core Flow /
35.4. 1.71 10 20 35.4, 1.64 35.4, 1.62 30 35.4, 1.92 40, 1.64 so.,.1/
40, 1.62 50, 1.55 Op0onB 40 50 70, 1.48
- 70. 1.40 70, 1.46 70, 1.38 60 70 Core Power (% Rated) 21.8, 2.10 21.8, 1.99 Ffgure2-1E Cycle 25 Power-Dependent MCPR Limits, El S MOC to SEQ A2-3, SLO
~ 50% Core Flow
/
< 50% Core Flow/
35.4, 1.92 40, 1.71 Option A I,,...,
35.4, 1.71 35.4, 1.66 35.4, 1.64 85, 1.45 85, 1.39 85, 1.37 80 90 40, 1.66 40, 1.64 70, 1.46 10 20 30 40 50 60 Core Power(% Rated)
Figure 2-1F 70 Cycle 25 Power-Dependent MCPR Limits, EIS SEQ A2-3 to EOC, SLO 85, 1.45 80 90 Tau ~0.2 100, 1.40 100, 1.34 100, 1.32 100 Tau a 0.2 100 LBDCR 2025- 0027
2.2 2.1 2.0 1.9 1.8 a: 1.7 ct CL 1.6 u
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8 a: 1.7 ci' 1.6 Q.
u
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
COLR Page 18 CORE OPERATING LIMITS REPORT
~ 50% Core Flow 21.8, 2.08 21.8, 1.97 35.4, 1.90 Option A 40, 1.68 35.4, 1.68
/70, 1.52 35.4, 1.62 70, 1.48 35.4, 1.60 40, 1.62 40, 1.60 70, 1.46 70, 1.43 OptionB 70, 1.44 70, 1.41 10 20 30 40 50 60 70 Core Power (% Rated)
Figure2-2A Cycle 25 Power-Dependent MCPR Limits with FWH 00S BOC to MOC, TI.O
- 50% Core Flow 21.8, 2.08 21.8. 1.97 I
< 50% Core Flow /
35.4, 1.90 10 20 35.4, 1.69 35.4, 1.62 35.4, 1.60 30 40, 1.69 40, 1.62 40, 1.60 40 Option B 50 60 Core Power (0/4 Rated)
Figure 2-2B 70, 1.53 70, 1.6 70, 1.43 70, 1.44 70, 1.41 70 Cycle 25 Power-Dependent MCPR Limits with FWH oos MOC to SEQ A2-3, TI.O 85, 1.48 85, 1.-13 85, 1.41 80 90 85, 1.49 85, 1.43 85, 1.41 80 90 Tau~ 0.2 100, 1.37 100, 1.32 100, 1.30 100 Tau =0.2 100, 1.38 100, 1.32 100, 1.30 100 LBDCR 2025-0027
2.2 2.1 2.0 1.9 1.8 ci: 1.7 ci' 1.6 Q.
u
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8 ci: 1.7 ct 1.6 Q.
u
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
COLR Page 19 CORE OPERATING LIMITS REPORT
- 50% Core Flow 21.8, 2.08 21.8, 1.97 I
< 50% Core Flow /
10 20 35.4, 1.69 35.4, 1.64 35.4, 1.62 30 40, 1.64 40, 1.62 40 so, 1.57 /
50, 1.SS Options 50 60 Core Power(% Rated)
Figure 2-2C 70, 1.53 70, 1.48 70, 1.45 70, 1.46 70, 1.43 70 Cycle 25 Power-Dependent MCPR Limits with FWH 00S SEQ A2-3 to EOC, 11.0 21.8, 2.10 21.8, 1.99
< 50% Core Flow /
10 20 35.4, 1.70 35.4, 1.64 3S.-4, 1.62 30
- 50% Core Flow 35.4, 1.92 40, 1.70 40, 1.62 40 50, 1.57 /
50, 1.55 Option e 50 60 Core Power (% Rated)
Flgure2-2D 70, 1.48 70, 1.45 70, 1.46 70, 1.43 70 Cycle 25 Power-Dependent MCPR Limits with FWH OOS BOC to MOC, SLO 85, 1.49 85, 1.43 80 85, 1.45 85, 1.43 80 90 90 Tau
- 0.2 100, 1.38 100, 1.34 100, 1.32 100 Tau ~ 0.2 100, 1.39 100, 1.34 100, t.32 100 I
LBDCR 2025-0027
2.2 2.1 2.0 1.9 1.8
- a: 1.7
~ 1.6 Q.
u
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8 a: 1.7
~ 1.6 Cl. u
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
COLR Page 20 CORE OPERATING LIMITS REPORT 21.8, 2.10
< 50% Core Flow 10 20
- ! 50% Core Flow
/
35.4, 1.92 Option A 35.4, 1.71 35.4, 1.64 35.4, 1.62 40, 1.71 I,._rn 30 40, 1.62 so, 1.57 /
so, 1.55 Option B 40 50 60 Core Power (% Rated)
Figure2-2E 70, 1.48 70, 1.45 70, 1.46 70, 1.43 70 Cycle 25 Power-Oepend nt MCPR Limits with FWH 00S MOC to SEQ A2-3, SLO 21.8, 2.10
< 50% Core Flow 10 20
- ! 50% Core Flow
/
3S.4, 1.92 Option A 35.4, 1.71 35.4, 1.66 40, 1.71 I 35.4, 1.64 30 40, 1.6-4 Option B 40 50 60 Core Power(% Rated)
Figure2-2F 70, 1.50 70, 1.47 70, 1.48 70, 1.45 70 Cycle 25 Power-Dependent MCPR Limits with FWH OOS SEQ A2-3 to EOC, SLO 80 80 85, 1.51 90 85, 1.51 90 Tau* 0.2 100, 1.40 100, 1.34 100, 1.32 100 Tau* 0.2 100, 1.40 100, 1.36 100, 1.34 100 LBDCR 2025-0027
2.2 2.1 2.0 1.9 1.8 a: 1.7 cl 1.6
- a.
u 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8 a: 1.7 cl 1.6
- a. u 1.5 1.4 1.3 1.2 1.1 1.0 0
10 20 CORE OPERATING LIMITS REPORT 35.4, 1.68 35.4, 1.62 35.4, 1.60 30
~ 50% Core Flow 35.4, 1.90 Option A 40, 1.68
/
70, 1.52 70, 1.48 40, 1.60 OptlonB 40 50 60 Core Power (% Rated)
Figure 2-3A 70, 1.46 70, 1.43 70, 1.44 70, 1.41 70 85, 1-43 as, 1.41 80 90 Cycle 25 Power-Dependent MCPR Limits with EOC-RPT oos, or EOC-RPT & FWH 00S BOC to MOC, TLO
.':'. 50% Core Flow 21.8, 2.08 I
21.8, 1.97
< 50% Core Flow /
35.4, 1.90 40, 1.71 35.4, 1.71 35.4, 1.63 35.4, 1.61 40, 1.63 40, 1.61 ~.,~ I 50, 1.54 70, 1.47 70, 1.44 70, 1.45 85, 1.42 Option B 70, 1.42 10 20 30 40 50 60 70 80 90 Core Power (% Rated)
Figure 2-38 Cycle 25 Power-Dependent MCPR Limits with EOC-RPT OOS, or EOC-RPT & FWH 00S MOC to SEQ A2-3, TLO Tau= 0.2 100, 1.37 100, 1.32 100, 1.30 100 Tau= 0.2 100, 1.39 100, 1.33 100, 1.31 100 COLR Page 21 LBDCR 2025-0027
2.2 2.1 2.0 1.9 1.8
~ 1.7 ix CL 1.6 u
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8
~ 1.7 ix CL 1.6 u
- E 1.5 1.4 1.3 1.2 1.1 1.0 0
CORE OPERATING LIMITS REPORT
.:: 50% Core Flow 21.8, 2.08 I
21.8, 1.97
< 50% Core Flow /
35.4, 1.90 40, 1-71 35.4, 1.71 70, 1.54 35.4, 1.64 35.4, 1.62 40, 1.64 40, 1.62 so.rn I 50, 1.55 70, 1.48 70, 1.45
- 70. 1.4&
as, 1.43 Option B 70, 1.43 10 20 30 40 50 60 70 80 90 Core Power(% Rated)
Figure2-3C cycle 25 Power-Dependent MCPR Limits With EOC-RPT 00S, or EOC-RPT & FWH 00S SEQ A2-3 to EOC, TLO
.:: 50% Core Flow 21.8, 2.10 21.&, 1.99
< 50% Core Flow /
35.4, 1.92 40, 1.70 35.4, 1.70 35.4, 1.64 35.4, 1.62
~.rn I 50, 1.55 85, 1.45 70, 1.4a 70, 1.45 85, 1.43 Option B 70, 1.46 70, 1.43 10 20 30 40 50 60 70 80 90 Core Power(% Rated)
Figure 2-30 Cycle 25 Power-Dependent MCPR Limits with EOC-RPT 00S, or EOC-RPT & FWH 00S BOC to MOC, SLO Tau - 0.2 100, 1.39 100, 1.34 100, 1.32 100 Tau ~0.2 100, 1.39 100, 1.34 100, 1.32 100 COLR Page 22 LBDCR 2025-0027
2.2 2.1 2.0 1.9 1.8 ii: 1.7 a:
- 0. 1.6 u :e 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8 ii: 1.7 a:
- 0. 1.6 u
- e 1.5 1.4 1.3 1.2 1.1 1.0 0
CORE OPERATING LIMITS REPORT
~ 50% Core Flow 21.8, 2.10
/
35.4, 1.92
< 50% Core Flow 40, 1.73 35.4, 1.73 35.4, 1.65 70, 1.56 35.4, 1.63 85, 1.52 40, 1.63 so.*~ I 85, 1.46 50, 1.56 70, 1.49 70, 1.46 85, 1.44 Option B 70, 1.47 70, 1.44 10 20 30 40 50 60 70 80 90 Core Power (% Rated)
Figure2-3E Cycle 25 Power-Dependent MCPR Limits with EOC*RPT 00S, or EOC-RPT & FWH 00S MOC to SEQ A2-3, SLO
~ 50% Core Flow 21.8, 2.10
/
35.4, 1.92
< 50% Core Flow 40, 1.73 35.4, 1.73 35.4, 1.66 70, 1.56 35.4, 1.64 85, 1.52 40, 1.64 so.*~ I so. 1.57 85, 1.47 70, 1.50 70, 1.47 85, 1.45 70, 1.43 Option B 70, 1.45 10 20 30 40 50 60 70 80 90 Core Power (0/o Rated)
Figure 2-3F Cycle 25 Power-Dependent MCPR Limits with EOC*RPTOOS, or EOC-RPT & FWH OOS SEQA2-3to EOC, SLO Tau = 0.2 100, 1.41 100. 1.35 100, 1.33 100 Tau = 0.2 100, 1.41 100, 1.36 100, 1.34 100 COLR Page 23 LBDCR 2025-0027
2.2 21 2.0 1.9 1.8
- 1.7
- a.
~ 1.6 Q. u
- e 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8 ci: 1.7
~ 1.6
- 0.
u
- e 1.5 1.4 1.3 1.2 1.1 1.0 0
COLR Page 24 CORE OPERATING LIMITS REPORT 21.S, 2.08 21.8, 1.97
< 50% Core Flow /
10 20 30
- -. 50% Core Flow 3S.4, 1.87 SO, 1.87 40 50 60 Core Power (% Rated)
Figure 2-4A 70.
80 90 Cycle 25 Power-Dependent MCPR Limits with PR OOS or PR & EOC RPT OOS BOC to MOC, TlO 21.8, 2.08 21.8, 1.97
< 50% Core Flow /
10 20 30
~ 50% Core Flow 35.4, 1.93 so, 1.93 40 50 60 Core Power (% Rated)
Figure 2-48 70 80 90 Cycle 25 Power-Dependent MCPR Limits with PR OOS or PR & EOC RPT 00S MOC to EOC, TlO 100, 1.38 100 100, 1.42 100 LBDCR 2025-0027
2.2 2.1 2.0 1.9 1.8
~ 1-7 0: 1.6 Q. u :s 1.5 1.4 1.3 1.2 1.1 1.0 0
2.2 2.1 2.0 1.9 1.8 0: 1.7 ii' 1.6 Ci. u :s 1.5 1.4 1.3 1.2 1.1 1.0 0
COLR Page 25 CORE OPERATING LIMITS REPORT
.'! 50% Core Flow 21.S, 2.10 21.8, 1.99 ----.:::::-,.."_
/
+-3-s._*._1_.ss_...,.. _____.....,
"50% core Flow 35.4, 1.89 so, 1.89 10 20 30 40 50 60 70 80 90 Core Power(% Rated)
Figure2-4C Cycle 25 Power-Dependent MCPR Limits with PR cos or PR & EOC RPTOOS BOC to MOC, SLO 21.8, 2.10 21.a, 1.99
< 50% Core Flow 10 20
.'! 50% Core Flow
/
35.4, 1.95 50, 1.95 30 40 50 60 Core Power(% Rated)
Figure2-40 70 80 90 Cycle 25 Power-Dependent MCPR Limits with PR oos or PR & EOC RPT 00S MOC to EOC, SLO 100, 140 100 100. 1.44 100 LBDCR 2025-0027
iii:
er Q. u :s iii:
er Q., u 2
2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 11 1.0 0
10 20 CORE OPERATING LIMITS REPORT 30
- 50% Core Flow 50,187 40 50 60 Core Power(% Rated)
Figure 2-5A 70, 1.86 70 80 100, us 90 100 Cycle 25 Power-Dependent MCPR Limits with PR & FWH oos or PR & FWH & EOC-RPT 00S BOC to MOC, TLO 2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0
- 50% Core Flow 21.8, 2.08 70, 1.97 21.8, 1.98
/
35.4, us
< 50% Core Flow so.us 100, 1.46 0
10 20 30 40 50 60 Core Power (% Rated)
Figure 2-5B 70 80 90 Cycle 25 Power-Dependent MCPR Limits with PR & FWH oos or PR & FWH & EOC-RPT oos MOC to EOC, TLO 100 COLR Page 26 LBDCR 2025-0027
0:
er Q.
u
,a 0:
er Q.
u 2
2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0 0
CORE OPERATING LIMITS REPORT
~ 50% Core Flow 21.8, 2.10 21.8, 2 00
< 50% Core Flow /
35.4, 1 *89 10 20 30 50, 1.89 40 50 60 Core Power (*/4 Rated)
Figu~2-5C 70, 1.88 70 80 100, 1.40 90 100 Cycle 25 Power-Dependent MCPR Limits with PR & FWH oos or PR & FWH & EOC-RPT oos BOC to MOC, SLO 2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0
~ 50% Core Flow 21.8, 2.10 70, 1.99 21.s. 2.oo I 35.4, 2.00
< 50% Core Flow 50, 200 100, 1.48 0
10 20 30 40 50 60 Core Power (% Rated)
Figure 2-50 70 80 90 Cycle 25 Power-Dependent MCPR Limits with PR & FWH oos or PR & FWH & EOC-RPT oos MOC to EOC, SLO 100 COLR Page 27 LBDCR 2025-0027
2.00 1.95 1.00 1.85 1.80 1.75 1.70
!£ 1.65 8: 1.60 0 :!, 1.55 1.50 1.45 1.40 1.35 1.30 1.25 CORE OPERATING LIMITS REPORT 90, 1-31 110, 1.31 81.2, 1.31 100, 1.31 1.20 -~--~-----~----------------------
0 10 20 30 40 50 60 70 80 90 100 110 Core Flow (% Rated)
Figure 2-GA Cycle 25 Flow-Dependent MCPR Limits, 11.0, All Application Conditions 2.00 1.95 1.00 1.85 1.80 1.75 1.70 C' 1.65 C( 1.60 Q. u 1.55
- E 1.50 0, 1.49 1.45 70, 1.41 1.40 1.35 80, 1.34 90, 1.33 110, 1.33 1.30 81.2, 1.33 100. 1.33 1.25 1.20 0
10 20 30 40 50 60 70 80 90 100 110 Core Flow (% Rated)
Figure 2-6B Cycle 25 Flow-Dependent MCPR Limits, SLO, All Application Conditions COLR Page 28 LBDCR 2025-0027
1.05 1.00 0.95 0.90
'ii:
tr 0.85
~
ex: 0.80 C!)
- c
..J 0.75 0.70 0.65 0.60 1.05 1.00 0.95 0.90
'ii:
tr 0.85
~
ex: 0.80
(!) :r
..J 0.75 0.70 0.65 0.60 CORE OPERATING LIMITS REPORT 354. 1.000 50, 1.000 70, 1000 85, 1.000 100, 1000 35.4, 0.896
< 50% Core Flow 21.8. 0,760 35.4, 0.730
- 50% Core Flow 218, 0 645 0
10 20 30 40 50 60 70 80 90 100 Power (% Rated)
Figure 3-1 Cycle 25 Power-Dependent LHGR Factor, EIS, FWH OOS, EOC-RPT OOS, EOC-RPT & FWH OOS Note: These factors to be applied to the exposure-dependent limits as descibed in Section 5.3 85, 1.000 100, 1,000
< 50% Core Flow 50, 0.849 21.8, 0 760
- 50% Core Flow 21.8. 0.645 0
10 20 30 40 50 60 70 80 90 100 Power (% Rated)
Figure 3-2 110 110 Cycle 25 Power-Dependent LHGR Factor PR OOS, PR & FWH OOS, PR & EOC-RPT OOS, PR & EOC-RPT & FWH OOS Note: These factors to be applied to the exposure-depiindent limits as descibed in Section 5.3 COLR Page 29 LBDCR 2025 - 0027
CORE OPERATING LIMITS REPORT 1.10 1.05 80.3, 1 000 90, 1.000 110, 1.000 1.00 0.95 100, 1.000 0.90 0.85 rr oso i1:
/;I:: 0.75
(!I 0.70
- x:
..I 0.65 0.60 0.55 0.50 0.45 o.40 0
10 20 30 40 50 60 70 80 90 100 110 120 Core Flow(% Rated)
Figure 3-3 cycle 25 GNF3 Flow-Oependent LHGR Factor Note: These fllctort to ~ applied to the expoture-dependent limits as descibed in Section 5.3 COLR Page 30 LBDCR 2025-0027
0 110 100 90 80
-10 s
l! 60
~
e...
CORE OPERATING LIMITS REPORT CORE FLOW (% rated) 10 20 30 40 50 60 70 80 90 Cycle 25 SSP Region J Implemented BSP Boundary 1--
ou, IUU 92.8, *oo Boundaries for NFWT
~
~ ~
- a......
I MELLLA+ Boundary L
./
I
.,,,.../' ~
~ -
~ ~
...I,,,,,,...._,,..,,-
_:a ~
! 5,80, 6..- ~
.-,, ~
~
__.. V I
~
- \\1 J
.... ~ 1/....
I J MELLLA Boundary
.?
I l
['-..
I
~.r':. ~5 71.:l I
..... i',.
L, ~
I
~ ~
V
/
I
.... ~,
I OPRM Armed Region 100 110 100, 00 05, 1 ~o Is*
~ Scram Region I
,,,,,-L r--
I k/
I
- a. 40
~
0 30 0
20 10 0
0 l"
I..--""*- I"'
~
I IL
~ Ii"""
I
./
/
Controlled Entry I I
~
/
I I
_i..-,,-,,..
t J,.,-,,_,.
I i.---'
~
R
,_ -- ~ -
J ~
I
/
ca ltaUi n Pri tecti ~n Note:
/
.ti SlO ls prohibited in MElUA+ region
_/
-~ -
/
10 20 30 40 50 60 70 80 90 100 110 120 CORE FLOW (MLBIHR}
Figure 4 Backup Stability Protection Region Boundaries for Normal Feedwater Temperature (NFWT)
I-COLR Page 31 LBDCR 2025-0027
0.0 110 10.0 20.0 30.0 100 90 80
-10
... 60
~
0 -
0:: 50
~
Q.40
~
030 0
20 10 0
I-Cycle 25 BSP Region
..... Boundaries for RFWT I MELLLA Boundary I I
~
,~
j Scram Region L
I
~ ~r----.....
~
111' I
~
~
R'.l i;- ~
,_ i-- i-I
/
/
i.-- ~
/
CORE OPERATING LIMITS REPORT CORE FLOW(% rated) 40.0 50.0 60.0 70.0 80.0 90.0 100.0 110.0
(~2.s,,100)
_,,,,, v 105~,,10(
! l tmplemented BSP Boundary :
- ~r--
i....- I""_,,,.,,,, 1--""""
~
~
l"'".....,...l-
.... ~
1,..,--""
AX _,,,,, 1/....
' I A1',c :/
I
..ti' ~ r I
I~ V
/)
I V
~r/
OPRM Armed Region h
I I
.JI. r--...
I
~ Controlled Entry I I
I I
~
Iii""
l
~ ~..-
li--""
Cl Witati 1n Pr t>tecti pn 0
10 20 30 40 50 60 70 80 90 100 110 120 CORE FLOW (MLBIHR)
Figure 5 Backup Stability Protection Region Boundaries for Reduced Feedwater Temperature (RFWT)