RS-08-063, Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System
| ML081340270 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  (NPF-011, NPF-018) |
| Issue date: | 05/13/2008 |
| From: | Simpson P Exelon Generation Co, Exelon Nuclear |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RS-08-063 SWJ:05:014, Rev 0 | |
| Download: ML081340270 (55) | |
Text
Exelon Generation www.exeloncorp.COM 4300 Winfield Road Warrenville, IL 60555 RS-08-063 10 CFR 50.90 May 13, 2008 U. S. Nuclear Regulatory Commission ATTN : Document Control Desk Washington, DC 20555-0001 LaSalle County Station, Units 1 and 2 Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374 Exelon Nuclear
Subject:
Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System Reference :
Letter from D. M. Benyak (Exelon Generation Company, LLC) to U. S. NRC, "Request for License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System," dated August 14, 2007 In the referenced letter, Exelon Generation Company, LLC (EGC) requested an amendment to Facility Operating License Nos. NPF-11 and NPF-18 for LaSalle County Station (LSCS), Units 1 and 2. The proposed change revises the licensing basis to allow ganged rod drive capability of the Rod Control Management System (RCMS). This letter provides supplemental information concerning this license amendment request (LAR) in response to Requests for Additional Information (RAls) that were transmitted by NRC emails dated January 2, January 24, and January 31, 2008, and clarified during teleconferences between EGC and the NRC on January 15, 2008 and April 10, 2008. The supplemental information is provided in the attachments to this letter, as follows:
" Attachment 1 provides a response to the NRC RAls.
0 Attachment 2 provides a Framatome ANP, Inc. evaluation supporting the proposed LAR.
May 13, 2008 U. S. Nuclear Regulatory Commission Page 2 There are no regulatory commitments contained in this letter.
If you have any questions concerning this letter, please contact Mr. Kenneth M. Nicely at (630) 657-2803 or Mr. John L. Schrage at (630) 657-2821.
I declare under penalty of perjury that the foregoing is true and correct. Executed on the 13th day of May 2008.
Patrick R. Simpson Manager - Licensing Attachments:
1.
Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System
- 2.
Framatome ANP, Inc., "Low Power CRWE Evaluation for LaSalle," October 31, 2005
ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System
Background
In e-mails dated January 2, January 24, and January 31, 2008, the NRC transmitted Requests for Additional Information (RAls) to Exelon Generation Company, LLC (EGC) concerning a license amendment request (LAR) for LaSalle County Station (i.e., letter from D. M. Benyak (Exelon Generation Company, LLC) to U. S. NRC, "Request for License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System," dated August 14, 2007, hereafter described as the "referenced LAR"). These RAls were discussed, and the questions were clarified during teleconferences between EGC and the NRC on January 15, 2008 and April 10, 2008.
The clarified NRC questions and the EGC response to each question are described below, as well as in an engineering evaluation that is provided in Attachment 2.
NRC Request 1 Part of the basis for ARTS-style credit of a reactivity management system is that the accident, if unmitigated by the reactivity management system, would result in very few, if any, fuel failures.
Reactor Systems would like to discuss the evaluation provided.
Provide information that the Rod Worth Minimizer (RWM) and Rod Block Monitor (RBM) are not credited in the mitigation of an accident or anticipated operational occurrence (AOO) below the automatic bypass setpoint of the RBM (i.e., the applicable power level for enabling of ganged rod withdrawal capability).
EGC Response Section 15.4, "Reactivity and Power Distribution Anomalies," of the LaSalle County Station (LSCS) Updated Final Safety Analysis Report (UFSAR) describes accidents, events, and AOOs that impact reactivity. In the description of accidents and AOOs, the LSCS Rod Worth Minimizer (RWM) and Rod Block Monitor (RBM) systems are not credited in the mitigation of an accident or AOO, below the automatic bypass setpoint of the RBM (i.e., the applicable power level for enabling ganged rod withdrawal capability).
The UFSAR description for the following accident and AOOs credit the RWM and RBM systems with prevention of an accident below the automatic bypass setpoint of the RBM as a "what if" in the event operator action/inaction fails to prevent the accident or AOO.
o Continuous Rod Withdrawal During Reactor Startup (UFSAR 15.4.1.2)
The RWM is credited with preventing an operator from selecting and withdrawing an out-of-sequence control rod. The probability of initiating causes (or multiple errors) for this event alone is considered low enough to warrant its categorization as an "infrequent incident."
The probability of further development of this event is extremely low because it is contingent upon failure of the RWM system, concurrent with high rod worth, out-of-sequence rod selection contrary to procedures, plus operator non-acknowledgment of continuous alarm annunciations prior to safety system actuation.
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ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System o
Control Rod Drop Accident (UFSAR 15.4.9)
The RWM is credited with minimizing the maximum rod worth prior to occurrence of the Control Rod Drop Accident (CRDA). However, the RWM cannot and does not perform any function to mitigate the CRDA once it occurs.
Similar to these events, the RWM, as part of the new Rod Control Management System (RCMS) will also be credited with prevention of the new "Multiple Rod Withdrawal Error on Startup" event.
The Continuous Rod Withdrawal during Reactor Startup event is described in UFSAR Section 15.4.1.2 as an infrequent incident, based solely upon the low probability of initiating causes for the event. However, UFSAR Section 15.4.1.2 does not address ganged rod motion as part of that accident. NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants," addresses the evaluation of this event for ganged rod motion in Section 15.4.1, Revision 3, "Uncontrolled Control Rod Assembly Withdrawal from a Subcritical or Low Power Startup Condition."
In Section 15.4.1 of NUREG-0800, for BWR/6 designs, the NRC reviewed the possibilities for single failures of the reactor control system that could result in uncontrolled withdrawal of control rods under low power startup conditions. The NRC concluded that the requirements of GDC 10, 17, 20, and 25 had been met, based upon the inclusion in the plant design of a Rod Pattern Control System (i.e., "Rod Block Instrumentation").
As described in NUREG-1434, "Standard Technical Specifications General Electric Plants, BWR/6," Volume 2, "Bases," Section 3.3.2.1, "Control Rod Block Instrumentation," the rod pattern controller, along with operator actions, ensures that "during start-up conditions, only specified control rod sequences and relative positions are allowed over the operating range of all control rods inserted to [10]% RTP." The NRC reviewed this system and found it acceptable because it precluded single failures in the Reactor Control System that could result in uncontrolled withdrawal of control rods under low-power conditions. The scope of the NRC review included the design features that act to prevent such withdrawals. The review also demonstrated that no single failure would permit an uncontrolled rod withdrawal that could lead to reactivity insertions greater than those routinely encountered during operation.
The EGC analysis in Section 3.3 of the referenced LAR, "Analysis of Potential Single Failures,"
demonstrated that the RCMS is also designed such that no single failure can cause an uncontrolled ganged rod withdrawal, and thus the NRC evaluation in Section 15.4.1 of NUREG-0800 for ganged rod motion at a BWR/6 is also applicable to ganged rod motion at LSCS.
Nevertheless, EGC has conducted a one-time evaluation of a postulated ganged rod withdrawal error at low power to evaluate the potential impact of this accident upon specified fuel design limits, relative to the acceptance criteria in NUREG-0800, Section 15.4.1, Items 2.a and 2.c.
This evaluation is provided in Attachment 2. This evaluation did not credit either the RWM or RBM to mitigate or stop the response of the reactor core. The evaluation was performed by evaluating ganged rod withdrawal scenarios using initial power levels of 5%, 10%, 15%, 20%,
25%, and 30%.
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ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System The evaluation indicates that in the event that a control rod gang is erroneously withdrawn out-of-sequence, the result will not challenge fuel integrity. As such, the impact of the infrequent incident, with respect to fuel design limits (i.e., minimum critical power ratio, linear heat generation rate, uniform cladding strain, and peak pin enthalpy), is within the acceptance criteria of NUREG-0800, Section 15.4.1, and is bounded by the spectrum of other analyzed accidents for LSCS (e.g., UFSAR 15.4.1.2, "Continuous Rod Withdrawal During Reactor Startup").
NRC Request 2 Provide an evaluation that demonstrates that an accident or AOO at low power levels (i.e.,
below the automatic bypass setpoint of the RBM) that is not mitigated by the reactivity management system, will not challenge the fuel integrity (i.e., the fuel design limits including Minimum Critical Power Ratio, Linear Heat Generation Rate, uniform cladding strain, and peak pin enthalpy, relative to the Acceptance Criteria of NUREG-0800, Chapter 15.4.1), and is bounded by the spectrum of other analyzed accidents for LSCS.
EGC Response provides the requested evaluation (i.e., Framatome ANP, Inc., "Low Power CRWE Evaluation for LaSalle," dated October 31, 2005), the conclusion of which was described in the EGC response to NRC Request 1.
NRC Request 3 We accept ATWS compliance based in part on acceptable operator actions. How is Exelon monitoring operator response to the ganged rod insertion capability?
EGC Response Licensed operator response to an anticipated transient without scram (ATWS) event is monitored during CR simulator drills as part of periodic licensed operator requalification training.
This training, including the Control Room (CR) simulator drills, is developed in accordance with EGC Training and Qualification (TQ) procedures. As part of RCMS implementation, including ganged rod drive capability, drills will be developed for low, mid, and high power ATWS scenarios, with and without balanced partial rod insertion across the rod gangs.
In response to the simulator ATWS event, the operator will insert control rods using either Gang or Single mode, based on the resulting rod pattern. In the event an operator leaves Gang mode selected for a gang that already has 3 of the 4 rods full in, the single rod will insert as fast as if Single mode were selected. This is due to the proper operation of the CRD system drive water pressure stabilizing valves. Operator response to the transient, including the use of ganged rod control, will be evaluated utilizing the EGC training performance monitoring and evaluation process.
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ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System NRC Request 4 What Accidents and AOOs use the cram rod capability? How does cram rod insertion affect the core?
EGC Response o Accidents Cram rod capability is not credited to mitigate any UFSAR Chapter 15 accident. Although not credited, cram rod capability may be used to provide a more rapid negative reactivity insertion during an ATWS event (i.e., UFSAR Section 15.8, "Anticipated Transients Without Scram (ATWS)").
o Anticipated Operational Occurrences (AOOs)
Cram rod capability can be used in response to several power excursion AOOs :
Increased Reactor Recirculation flow Reduced Feedwater (FW) temperature Imminent equipment failures (e.g., Main Power Transformer loss-of-cooling, Loss of Main Generator Stator Water Cooling, Reactor Recirculation Pump Loss, Condenser Vacuum degradation)
Oscillating Power Range Monitoring System High Alarms (i.e., Core Instabilities)
From an operational perspective, the insertion of a cram rod gang would replace the current procedure of four discrete rod insertions performed sequentially over an approximately four-minute period. The new procedure would enable an operator to insert the same four rods over a one-minute period. This will result in the same change to core power distribution.
Although the change in core power due to a cram rod insertion would occur over a shorter time period, relative to single rod insertion, the time frame for the change in core power distribution would still be significantly greater than a reactor scram.
NRC Request 5 What changes in fuel design could result from the enhanced ramp-up capability? Is the ramp rate changing appreciably? How will increases in ramp rate affect the fuel?
EGC Response o What changes in fuel design could result from the enhanced ramp-up capability?
There are no changes in fuel design. Current EGC fuel conditioning limits will still be applicable and will continue to limit the ramp rates with reactor power above 30%. Below 30% power, ramp rates are limited to less than 300 MWe per hour by balance-of-plant (BOP) requirements and procedures. This low power ramp rate limitation will not change with ganged rod withdrawal.
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ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System o
Is the ramp rate changing appreciably?
At the low power levels where ganged rod withdrawal will be used (i.e., 0% to 30% power),
the fuel conditioning limits do not restrict the ramp rate. As such, ramp rates are limited by balance-of-plant concerns to 300 MWe per hour or less.
The current procedure of selecting and moving individual rods limits the ramp rate to an average range between approximately 50 MWe per hour and 100 MWe per hour. The use of ganged rod withdrawal would result in periods of time where the ramp rate may average closer to the 300 MWe per hour.
In this case, the use of ganged rod withdrawal would require less discrete rod pulls, and hence less chance for selection or motion direction start errors.
How will increases in ramp rate affect the fuel?
As stated above, ramp rates below 30% power are limited by BOP concerns, as opposed to fuel conditioning limits.
Therefore, any increase in ramp rates through the use of ganged rod withdrawal will not affect the fuel.
NRC Request 6 LaSalle is requested to provide : Software QA Plan/Procedures, System Description to Block Diagram Level, QA Plan for digital HW and SW, Software Configuration management Plan, Software Design Specification, Software Integration Plan, Software Maintenance Plan, Software Management Implementing Procedures, Software Test Procedures, Requirements Traceability Matrix, V&V Procedure, V&V Reports (9 months after LAR submittal), Test and V&V Problem Reports (Available for audit), Vendor as-built documentation (Available for audit), Site Acceptance Test Report (Available for review by the Region), Summary of test results and problem reports with resolution (Available for audit prior to operation).
EGC Response As part of the referenced LAR, EGC described the processes, specifications, and procedures that are listed in NRC Request 6, and provided the applicable documents in Attachment 2 of the LAR, with the exception of test, verification, and audit report documents that are not yet available (i.e., Verification and Validation (V&V) Reports, Test and V&V Problem Reports, Vendor as-built documentation, Site Acceptance Test Report, and the Summary of test results and problem reports with resolution identified).
The documents that were submitted in the referenced LAR are proprietary to General Electric (GE) - Hitachi Nuclear Energy Americas LLC (GEH). As such, EGC requested that the information be withheld from public disclosure in accordance with 10 CFR 2.390, "Public inspections, exemptions, requests for withholding," paragraph (a)(4), and 10 CFR 9.17, "Agency records exempt from public disclosure," paragraph (a)(4). An affidavit attesting to the proprietary nature of this information was included in Attachment 3 of the referenced LAR.
The following description provides a cross-referenced accounting for the requested documents in the referenced LAR:
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ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System o Software QA Plan/Procedures; QA Plan for digital HW and SW ; Software Configuration Management Plan ; Software Maintenance Plan ; Software Management Implementing Procedures ; Software Test Procedures ; Requirements Traceability Matrix ; V&V Procedure Section 3.2.7 of Attachment 1 in the referenced LAR provided a description of software development, testing, and configuration control for the RCMS system. The software for the RCMS equipment was developed using the General Electric (GE) Nuclear Measurement Analysis and Control (NUMAC) Software Configuration Management Plan (SCMP), the GE NUMAC Software Management Plan (SMP), and the GE NUMAC Software Verification and Validation Plan (SVVP) process, as modified in GE Nuclear Energy DRF 0000-0038-3006, Revision 2, "Rod Control Management System (RCMS) Software Development Plan," dated March 9, 2007.
The GE NUMAC software process is GE's standard safety-related software development process. This process has been submitted to the NRC multiple times and has been accepted for use in safety-related software. The most recent examples were license and TS amendments approving the implementation of a NUMAC Power Monitoring system at Susquehanna station. The NRC approved these applications of the NUMAC software process in Safety Evaluations dated March 3, 2006 (i.e., ML Accession # ML060540429) and March 23, 2007 (i.e., ML Accession # ML070720675).
Documents that describe the software design, verification, and control for the RCMS were included in Attachment 2 of the referenced LAR, as described below:
Item 1 of Attachment 2 in the referenced LAR provided GE Nuclear Energy DRF 0000-0038-3006, Revision 2, "Rod Control Management System (RCMS) Software Development Plan." The RCMS Software Development Plan specifically addresses software design control, change control, documentation, record keeping, independent verification, and software development requirements, as described in RG 1.152, "Criteria for Digital Computers in Safety Systems of Nuclear Power Plants," Revision 2.
Item 2 provided the "GE Nuclear Energy NUMAC Software Management Plan," (i.e.,
23A5162, Revision 3). This document describes the process for the design, development, and maintenance of NUMAC product software.
Item 1, Section 2.5.3, "Traceability of Software Functional Testing to Software Requirements," and Section 2.7 describe the use of a "requirements traceability matrix" to help identify software requirements and provide traceability of all software testing to the software requirements and specifications. This includes software testing in both a "white box" test environment (i.e., module testing, integration testing, and code reviews as part of the software development process) and a "black box" test environment. The requirements traceability matrix is a database tool that is used, in concert with the software requirements and specifications, to confirm that all of the software testing requirements are satisfied.
Item 3 provided the "GE Nuclear Energy NUMAC Software Verification and Validation Plan," (i.e., 23A5163, Revision 3). This document describes the Software Verification and Validation Plan (SVVP) process used for all NUMAC product software.
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ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System o Software Design Specification Section 3.3.2 of Attachment 1 in the referenced LAR provided a description of RCMS software design features and requirements. This description is based upon specification documents that were included in Attachment 2 of the referenced LAR, as described below:
o System Description to Block Diagram Level Section 3.2.3 of Attachment 1 in the referenced LAR provided a description of the RCMS components, specifications, and interfaces.
Section 3.2.6 of Attachment 1 in the referenced LAR described the qualification of RCMS components and equipment. As stated in Section 3.2.6, the RCMS and components have been built to the GE Nuclear Energy Quality Assurance Program, NEDO-11209-04A, Revision 8, which has been reviewed and accepted by the NRC. This program meets the requirements of ANSI N45.2, and 10 CFR 50, Appendix B.
The descriptions in Sections 3.2.3 and 3.2.6 of the referenced LAR for RCMS components, interfaces, and qualifications are based upon specification documents that were included in of the referenced LAR, as described below:
Item 5 provided the "RCMS/MCR Controller Performance Specification," (i.e., 26A6515, Revision 6). This document describes the software performance capabilities of the RCMS Controllers and Main Control Room (MCR) Controllers, including block diagrams of hardware configuration and a processing signal flow diagram.
Item 10 provided the "Rod Control Management System (RCMS) Displays," specification (i.e., 26A6609).
This document specifies software performance requirements for microprocessor-based RCMS display units, and addresses operator actions and display-related functions at all of the displays.
Item 11 provided the "File Control Processor Performance Specification," (i.e.,
26A6616).
This document describes the performance of the File Control Processor (FCP) card with respect to its use as a Rod Position Information System (RPIS) subassembly in the RCMS. The FCP serves as the master control for all the Probe Multiplexer cards in a Multiplexer file (i.e., the mechanism for transmitting position information and commands to and from the RCMS to the individual control rod drives).
Item 4 provided the "Rod Control Management System Requirements Specification,"
(i.e., 26A6356, Revision 4). This document defines the design and performance requirements for the design and manufacture of the RCMS system, including detailed descriptions of the RCMS components and block diagrams for the system.
Item 6 provided the "Rod Control Management System (RCMS) External Interface Specification," (i.e., 26A6517, Revision 3). This document describes the external interfaces of the RCMS with the existing plant computers.
Item 7 provided the "RCMS Human System Interface Specification," (i.e., 26A6518, Revision 4). This document defines all graphical user interface screens for the RCMS, including the basis for the Human Factors Engineering analysis that was performed for the RCMS system.
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ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System Item 8 provided the "RCMS and MCR Interface Performance Specification," (i.e.,
26A6530, Revision 4). This document defines the performance requirements for the RCMS and MCR interface. Although the system contains two channels of both RCMS and MCR interfaces, the specification has been developed from the perspective of hardware/software residing on a single channel of each interface.
Item 9 provided the "Rod Control Management System (RCMS) Internal Communication Protocol Specification," (i.e., 26A6582, Revision 2). This document defines all internal interfaces of the microprocessor-based RCMS.
Item 10 provided the "Rod Control Management System (RCMS) Displays," specification (i.e., 26A6609).
This document specifies software performance requirements for microprocessor-based RCMS display units, and addresses operator actions and display-related functions at all of the displays.
NRC Request 7 The touch-screen VDU is used for RCMS controls. The VDU is not seismically qualified even though it is mounted seismically (where required) to account for II/I concerns. Please justify how LaSalle intends to handle multiple spurious actuations in case of a seismic event.
EGC Response The RCMS components are not safety-related or seismic, but are seismically installed in the cabinets and panels to satisfy seismic II/I concerns, where required. The components have similar chassis and construction as NUMAC hardware that is qualified to meet the seismic test criteria for safety-related applications. Additional information concerning the conformance of this equipment to seismic test criteria is provided in Item 4 of Attachment 2 to the referenced LAR.
In the main control room (MCR), the operator video display interface is comprised of three LCD display screens - one is the 40-inch full core map and the other two are 20-inch touch activated screens for monitoring and control. The 40-inch full core map graphically displays control rod position information, and does not provide any control or selection function.
The 40-inch display and the two 20-inch touch screens are controlled by the two MCR Controllers (i.e., one for the full core display and one 20-inch display, and one for the other 20-inch display). On the MCR 20-inch rod select screen, the operator can select a rod by touching the rod button on the screen. Once a rod is selected, the operator then can use the pushbuttons on the MCR Rod Select Panel (i.e., hard-wired physical, "Hall-Effect" switches, not software switches) to start rod motion.
The RCMS utilizes the same operating scheme for rod motion pushbuttons as currently installed for the Reactor Manual Control System. The RCMS pushbuttons are mechanically recessed into the Rod Select Console requiring the depressing slightly below the surface of the console, similar to the surrounding collar of the original design. In addition, as with the current rod control design, continuous rod withdrawal with RCMS requires the simultaneous pressing of the two pushbuttons on opposite sides of the Rod Select Console (i.e., requiring two-handed operation). The RCMS pushbuttons are slightly smaller than the current pushbuttons, providing a smaller target for a seismic event. Therefore, even if a rod is already selected with the new Page 8 of 14
ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System RCMS during a seismic event, the probability of an inadvertent notch withdraw is approximately the same or lower as with the current design. Similarly, the recessed buttons and two-handed operation makes inadvertent rod withdraw not credible during a seismic event.
Rod movement requires two actions by the operator. Selection of the desired rod is accomplished from the 20-inch touch screen (in control) and rod movement is requested by the pushbuttons on the Rod Select Console. The 20-inch touch screens that are used in the RCMS design are capacitive touch, (i.e., based on the typical capacitance from a finger). In the event of a seismic event, these displays are adequately mounted to the H13-P603 panel and are not sensitive to falling objects or debris from other systems. In addition, a seismic event of enough magnitude to cause erratic indication or display on the 20-inch MCR touch screen would provide sufficient physical indication to the control room operator to preclude operation of the two RCMS pushbuttons, and/or terminate the use of these pushbuttons. Thus any erratic behavior in the VDU would have no adverse affect on rod motion.
NRC Request 8 Cyber security has been addressed in Section 3.2.5 of the submittal. Per Figure 6.1, Defensive Model of NEI 04-04, Control and Safety Systems are categorized as Level 4 with no two-way communication. LaSalle Figure 3, RCMS External Network Diagram shows two-way communications. Please provide analysis or justification explaining how the network diagram meets the NEI 04-04 guidance.
EGC Response EGC has completed a cyber security risk assessment at LSCS in accordance with Nuclear Energy Institute (NEI) 04-04, Revision 1, "Cyber Security Program for Power Reactors," and NUREG/CR-6847, "Cyber Security Self-Assessment Method of U. S. Nuclear Power Plants," for site Critical Digital Assets, including the proposed design for RCMS. The proposed RCMS design was ranked as Very Well Protected, with a susceptibility level of 2, a risk category of B-4, and was deemed an Acceptable Risk with no design-related mitigation required. As such, the proposed RCMS design, as an LSCS Critical Digital Asset, satisfies the intent and purpose of NEI 04-04.
Section 3.2.5 of the referenced LAR states that all RCMS components, with the exception of the RCMS Controllers, are connected to each other via a dedicated private network, with no direct connection to the higher level networks. Each RCMS Controller is connected to both the Plant Process Computer (PPC) and the RWM Sequence Computer via dedicated connections. These connections only provide bi-directional messaging capabilities between the RCMS Controllers and both the PPC and RWM systems; no access to RCMS control functions is directly available via these links.
Item 6 of Attachment 2 to the referenced LAR provided the "Rod Control Management System (RCMS) External Interface Specification," (i.e., 26A6517, Revision 3). This document describes the interfaces of the RCMS Controllers with the two PPCs (i.e., A and B) and the RWM Sequence Computer. The PPCs and RWM connect with the RCMS Controller on a TCP IP link.
Up to two TCP connections are active at a time between each PPC and an RCMS Controller (i.e., a Data Connection and a Status Connection). One TCP connection is active between the RWM and an RCMS Controller.
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ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System o Messages sent to RCMS Controller by the PPC Over the Data Connection Utilizing the Data Connection, the PPC will send a "Rod Scram Timing Data" request to the RCMS Controller. This data is normally available and stored in the RCMS Controller cyclic buffer. If no scram timing data exists in the RCMS Controller, a corresponding message is returned to the PPC. The format for the request is the only format that the RCMS Controller will acknowledge. This transfer is a low priority in the RCMS and thus will not override higher priority programming in the RCMS.
o Messages sent to RCMS Controller by the PPC Over the Status Connection Utilizing the Signal Connection, the PPC will send a PPC status message to the RCMS Controller every 1000 milliseconds. This message contains current PPC status and time information.
The timestamp in the message is used to update the timestamp of the RCMS Controller.
The RCMS Controller time clock is synchronized with the "Synchronization Time" that is provided in the PPC Status Message. The status and timestamp message from the PPC is a fixed format message that is the only acceptable format that the RCMS Controller will use for time synchronization.
Synchronization is performed at midnight each night, as well as when the following criteria are satisfied :
No rod motion occurring, and A time difference between the RCMS Controller timestamp and PPC timestamp greater than 100 milliseconds.
Data and signal transfer from the external PPC to the RCMS Controller, including the timestamp, provides no control activity, and must be in a specified format for use by the RCMS Controller. Therefore, there is no dependency relationship between the RCMS Controller (i.e., an NEI 04-04 "Control & Safety System") and the PPC (i.e., an NEI 04-04 "Data Acquisition System").
o Messages sent to RCMS Controller by the RWM Sequence Computer The RWM Sequence Computer will send the following messages to the RCMS Controllers:
Operating Sequence Upload Request, Operating Sequence Download Data, and RWM Status Request.
Data and signal transfer from the external RWM Sequence Computer to the RCMS Controller provides no control activity. Therefore, there is no dependency relationship between the RCMS Controller (i.e., an NEI 04-04 "Control & Safety System") and the RWM Sequence Computer (i.e., an NEI 04-04 "Data Acquisition System").
EGC has determined that the dedicated connections between the RCMS Controller and both the PPC and the RWM Sequence Computer (i.e., the "PPC Private Network Switch" that is depicted in Figure 3 of the referenced LAR), in concert with the type of data transferred to the RCMS Controller from the PPC and RWM Sequence Computer, establish an acceptable variation from the Defensive Model that is depicted in Figure 6.1 of NEI 04-04.
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ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System NRC Request 9 Provide information concerning operator actions (added, deleted, or changed) and their impact on EOPs, DBAs, and PRAs.
EGC Response o Impact of Revised Operator Actions on EOPs Section 3.2.9 of Attachment 1 in the referenced LAR describes the impact of RCMS upon the Emergency Operations Procedures (EOPs). RCMS will provide all the current expected functions for the EOP process. Other than the revised operator interface in the control room, there will be no difference in the displays for the EOP required indications. The new RCMS will enhance the information available to the control room for EOP events with improved shutdown confirmation displays.
With respect to ganged rod drive capability, the only applicable EOP is LGA-010, "ATWS."
The change to this EOP will include the use of ganged rod insertion, which will help to achieve a shutdown state sooner. The actual change will likely be similar to a footnote directing the operator to use ganged rod insertion, if available.
o Impact of Revised Operator Actions on DBAs Both the existing Reactor Manual Control System (RMCS) and the new RCMS are not safety-related, are not used for plant shutdown resulting from accident or nonstandard operational conditions, and are not assumed to function during the events analyzed in Chapter 15 of the LSCS Updated Final Safety Analysis Report, including the Control Rod Drop Accident, Control Rod Removal Error During Refueling, Rod Withdrawal Error - at Power, and Continuous Rod Withdrawal during Reactor Startup.
The new RCMS has no interaction with the safety-related portion of the reactivity control system. Therefore, any revised operator actions associated with the implementation of RCMS and ganged rod drive capability will not impact any Design Basis Accidents.
o Impact of Revised Operator Actions on PRA As described above, RCMS has no interaction with the safety-related portion of the reactivity control system, nor is it credited to function during the events analyzed in Chapter 15 of the LSCS UFSAR. Therefore, current and revised operator actions associated with RCMS are not modeled in the LSCS PRA, and consequently have no effect.
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ATTACHMENT I Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System NRC Request 10 Provide information concerning training development and implementation.
EGC Response Development and implementation of licensed operator training at EGC, including any required training on the RCMS and ganged rod drive capability is defined and directed by a series of standardized procedures, as delineated below.
o TQ-AA-1, Training and Qualification o TQ-AA-10, Training System Development Process Description o TQ-AA-150, Operator Training Programs o
TQ-AA-221, Exelon Nuclear Training - Analysis Phase o
TQ-AA-222, Exelon Nuclear Training - Design Phase o
TQ-AA-223, Exelon Nuclear Training - Development Phase o
TQ-AA-224, Exelon Nuclear Training - Implementation Phase o
TQ-AA-225, Exelon Nuclear Training - Evaluation Phase Although this training has not been completely developed and implemented for RCMS and ganged rod drive capability, this training will include CR simulator drills for low, mid, and high-power ATWS scenarios, with and without balanced rod insertion across the rod gangs. In these scenarios, licensed operators will then insert control rods, using either gang or single-rod control, based on the resulting rod pattern. Operator performance during these drills will be evaluated in accordance with the normal training performance evaluation process.
NRC Request 11 Provide information concerning simulator impact and planned mods.
EGC Response Prior to completion of RCMS installation, EGC will update the LSCS simulator to reflect the RCMS modification, and utilize the updated simulator to train operators, as described in the response to NRC Request 10.
NRC Request 12 Provide information concerning control room layout, displays, alarms, controls (added, deleted, or changed).
EGC Response Section 3.2.4 of the referenced LAR, "Internal Communication and Data Interfaces," provides a summary of the equipment, controls, and operator processes for the LSCS RCMS. Detailed descriptions of the changes to the LSCS MCR layout, including new equipment, alarms, and Page 1 2 of 14
ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System controls is described in multiple specifications that were provided in Attachment 2 of the referenced LAR.
Specifically, Item 4 provided the "Rod Control Management System Requirements Specification," (i.e., 26A6356, Revision 4). This document provided detailed descriptions of the RCMS components and block diagrams for the system. In particular, Section 3.0 describes the hardware requirements ; Section 4.4 describes the operator control and display system ; and Section 8.0 describes the user interface with respect to controls and displays.
Item 7 provided the "RCMS Human System Interface Specification," (i.e., 26A6518, Revision 4).
This document defines all graphical user interface screens for the RCMS, including the basis for the Human Factors Engineering analysis that was performed for the RCMS system.
Item 10 provided the "Rod Control Management System (RCMS) Displays," specification (i.e.,
26A6609).
This document addresses operator actions and display-related functions at all of the RCMS displays.
In addition to these documents, during a public meeting with the NRC on September 19, 2006, EGC provided a presentation on the design and functionality (i.e., ADAMS Accession Numbers ML062920419 and ML063330288). This presentation included a description and graphical representation of the new RCMS equipment in the control room.
NRC Request 13 Provide information concerning operating experience and how it was factored into the design.
EGC Response During the design specification phase of RCMS development, EGC reviewed all GE Service Information Letters (SILs) concerning control rod drive and reactivity controls. Applicable operating experience from these SILs was addressed in the RCMS design. Primarily, the operating experience associated with ganged rod drive capability that was reviewed addressed ATWS response, shutdown confirmation, and a faster RPIS scan rate.
The final RCMS design is leveraged heavily from experience derived from the existing GE-Advanced Boiling Water Reactor (ABWR) design, as well as existing NUMAC hardware, software, and displays. The RCMS design inputs include the existing system design specification and system elementary diagram.
NUREG-0700, "Human-System Interface Design Review Guidelines," formed the basis for development of the RCMS operating displays. This design was based on the ABWR human factors engineering (HFE) design, as well as, extensive reviews from LSCS operations personnel (i.e., as described in the response to NRC Request 14 below). Existing RCMS color schemes and Display Primitives were selected by LSCS operations personnel to provide similar appearance as the existing Rod Control System with enhanced surveillance and operating capabilities.
Page 1 3 of 14
ATTACHMENT 1 Supplemental Information Concerning License Amendment to Allow Ganged Rod Drive Capability of the Rod Control Management System NRC Request 14 Provide information concerning human factors V&V, including any planned "man-in-the-loop" testing.
EGC Response Throughout the RCMS design process, EGC utilized a dedicated Reactor Operator (RO) and Senior Reactor Operator (SRO) for input and guidance. These NRC-licensed operators, in conjunction with GE experts, played a primary role in the human factors design of RCMS.
Additional LSCS SROs and ROs were also consulted, and evaluations were performed, resulting in the development of a design mock-up that enabled the SROs and ROs to test different designs for the rod movement control switches in the new RCMS (i.e., the push buttons that are used by the operator to withdraw and insert a control rod). In addition, the actual RCMS CR equipment has been assembled in a dedicated, non-production area at LSCS, and has been manipulated by SROs and ROs, utilizing V&V procedures. Thus, significant real-time evaluation and mock-up testing of the RCMS by licensed operators has been a significant input into an integrated "man-in-the-loop" evaluation.
With respect to a standard human factors review of the RCMS, the graphical user interface screens were developed in accordance with an HFE program that defined the information, controls, and alarms for controlling and monitoring the RCMS. Although the RCMS has no safety-related functions, the following codes, standards, and guidelines were used as the basis for the HFE analysis that was performed for this system.
Institute of Electrical and Electronics Engineers (IEEE) Standard 1023 -1988, "IEEE Guide to the Application of Human Factors Engineering to Systems, Equipments and Facilities of Nuclear Power Generating Stations."
International Electrotechnical Commission (IEC) Publication 964, "Design for Control Rooms of Nuclear Power Plants, 1989."
NUREG-0700, Revision 2, "Human-System Interface Design Review Guideline."
NUREG-0711, "Human Factor Engineering, Program Review Level."
NUREG-0800, Revision1, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants," Chapter 18, "Human Factor Engineering."
NUREG/CR-3331, "A Methodology For Allocating Nuclear Power Plant Control Functions to Human and Automated Control."
Page 14 of 14
ATTACHMENT 2 Framatome ANP, Inc., "Low Power CRWE Evaluation for LaSalle," October 31, 2005
AREVA Ref.:
1. E-mail, C. M. Powers to S. W. Jones, "TDS NF-130279,"
July 8, 2005 Attached is the final letter report for the evaluation of low power CRWE with ganged control rod withdrawal that has been prepared for LaSalle. The report is non-proprietary as specified in the Reference work authorization.
The results have been documented in accordance with FANP QA program. Modifications to the report were made to address the comments provided by Exelon on the preliminary report. The most significant change was the discussion of the fuel enthalpy. NUREG 1433 was added as a reference for the 170 cal/g threshold for fuel failure protection for the low power rod withdrawal event.
Please forward this report to Exelon.
Approved : W C O. C. Brown, Manager Date BWR Neutronics Approved :
.~ AfVV 0S_"
D.
. P tt, Manager Date Methods Development sip Attachment Framatorne ANP, Inc.
An AREVAand Siemens Company 2101 Horn Rapids Road Tel :
509 375 8100 Richland, WA 99354-5102 Fax:
509 375 8402 Framatome ANP, Inc.
SWJ:05:014 Date :
October 31, 2005 Distribution To :
C. M. Powers D. G. Carr sr~
R. J. DeMartino From:
S. W. Jones P. D. Wimpy
Subject:
Low Power CRWE Evaluation for LaSalle
SWJ :05:014 Revision 0 Low Power CRWE Evaluation for LaSalle Rod Control Management System October 2005
Framatome ANP, Inc.
Low Power CRWE Evaluation for LaSalle Rod Control Management System SWJ:05 :014 Revision 0
or Customer Disclaimer Important Notice Regarding Contents and Use of This Document Please Read Carefully Framatome ANP, Inc.'s warranties and representations concerning the subject matter of this document are those set forth in the agreement between Framatome ANP, Inc. and the Customer pursuant to which this document is issued.
Accordingly, except as otherwise expressly provided in such agreement, neither Framatome ANP, Inc. nor any person acting on its behalf :
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makes any warranty or representation, express or implied, with respect to the accuracy, completeness, or usefulness of the information contained in this document, or that the use of any information, apparatus, method, or process disclosed in this document will not infringe privately owned rights ;
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SWJ:05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page i Item Page Description and Justification 1.
All This is a new document.
Framatome ANP, Inc.
Nature of Changes
SWJ :05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page ii Contents Framatome ANP, Inc.
1.0 Introduction and Summary..................................................
...........................................1-1 2.0 Background.......................................................................
.............................................2-1 3.0 MCPR Evaluation...........................................................................................................3-1 4.0 LHGR Evaluation...........................................................................................................4-1 5.0 Enthlapy Evaluations......................................................................................................5-1 6.0 References.....................................................................................................................6-1 Tables 2.1 Assumed Pull Sequence Following Group 4..................................................................2-2 3.1 BOC A Sequence MCPR for Low Power CRWE
........................................................... 3-2 3.2 PHE A Sequence MCPR for Low Power CRWE............................................................3-2 3.3 EOC A Sequence MCPR for Low Power CRWE...........................................................3-2 3.4 BOC B Sequence MCPR for Low Power CRWE
...........................................................3-2 5.1 BOC A Sequence Rod Withdrawal Below 5% Power....................................................5-3 5.2 Relative Peak Fuel Enthalpies from Rod Withdrawal Error............................................ 5-3 5.3 Relative Peak Fuel Enthalpies and Rod Worths for PHE A Sequence Rod Withdrawal Error............................................................................................................5-4 5.4 Relative Peak Fuel Enthalpies and Rod Worths for EOC A Sequence Rod Withdrawal Error............................................................................................................5-5 5.5 Adiabatic Enthalpy Results............................................................................................5-5
SWJ :05:014 Framatome ANP, Inc.
Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page iii Figures 2.1 LaSalle A-Sequence Gangs, Control Rod Numbers, and IRM locations.......................2-3 2.2 LaSalle B-Sequence Gang Definitions...........................................................................2-4 3.1 DMCPR/IMCPR versus Gang Worth BOC A-Sequence................................................ 3-3 3.2 DMCPR/IMCPR versus Gang Worth PHE A-Sequence................................................3-4 3.3 DMCPR/IMCPR versus Gang Worth EOC A-Sequence................................................ 3-5 3.4 DMCPR/IMCPR versus Gang Worth BOC B-Sequence................................................ 3-6 4.1 Maximum Fraction of Limit for LHGR.............................................................................4-2 4.2 Maximum Delta LHGR Divided by LHGR Limit..............................................................4-3 5.1 Hot Channel Average Enthalpy for Rod Withdrawal at 30% Power
............................... 5-6 5.2 Hot Pin Enthalpy for Gang Withdrawals Starting from 75% Rod Density....................... 5-7 5.3 Hot Pin Enthalpy for Gang Withdrawals Starting from 63% Rod Density....................... 5-8 5.4 Hot Pin Enthalpy for Gang Withdrawals Initiated at 5% Power...................................... 5-9 5.5 Hot Pin Enthalpy for Withdrawals Initiated at 0.2% Power
........................................... 5-10 5.6 IRM Signal Responses for Withdrawal of Rod 156......................................................5-11 5.7 IRM Signal Responses for Withdrawal of Gang G09D................................................ 5-12
SWJ :05 :014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page iv Nomenclature BOC beginning of cycle BPWS banked position withdrawal sequence CPR critical power ratio CRWE control rod withdrawal error DMCPR change in minimum critical power ratio EOC end of cycle FANP Framatome ANP (Advanced Nuclear Power), Inc..
GNF Global Nuclear Fuels IMCPR initial minimum critical power ratio IRM intermediate range monitor LHGR linear heat generation rate MCPR minimum critical power ratio PHE peak hot excess reactivity RBM rod block monitor UFSAR updated final safety analysis report OCPR change in critical power ratio Framatome ANP, Inc.
SWJ:05 :014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 1-1 1.0 Introduction and Summary Implementation of the rod control management system (RCMS) at LaSalle allows for ganged control rod pulls below the rod block monitor operability. The current updated final safety analysis report (UFSAR) (Reference 1) identifies the low power rod withdrawal as not a credible event. Although it is believed that the low power rod withdrawal error will not be a credible event with the implementation of the RCMS and gang withdrawal, an evaluation has been performed to demonstrate that the ganged withdrawal below the Rod Block Monitor (RBM) operation is bounded by other events.
The evaluation was performed using the CASM04/MICROBURN-B2 approved methodology (Reference 2) and the RAMONA5-FA code ( not approved References 3, and 4.) The evaluations were performed in a manner consistent with Standard Review Plan (SRP) 15.4.1-3 (Reference 5) to the extent possible. For power levels above 5% and up to the power level of RBM operability, the CASM04/MICROBURN-B2 methodology was used to evaluate the impact of the ganged control rod withdrawal error (CRWE) on critical power ratio (CPR) and linear heat generation rate (LHGR). The evaluation was completed at various exposures with the LaSalle Unit 1 Cycle 12 core design.
The control rod patterns evaluated were typical startup sequences with the exception of the actual error rod or gang of rods. Until the time of the actual rod withdrawal error, the pattern is maintained with the Rod Worth Minimizer and is in accordance with BPWS.
The CASM04/MICROBURN-B2 methodology was also used to identify the strongest gang RWE events below 5% power. The RAMONA5-FA code (a three dimensional, coupled neutron kinetics-thermal hydraulics model) was used to evaluate the intermediate range monitor (IRM) instrument response at power levels below 5% and the peak pin fuel enthalpy.
The criteria used in this evaluation are those presented as Acceptance Criteria items 2.a and 2.c of SRP 15.4.1 (Reference 5).
2.
The requirements of GDC 10, 20, and 25 concerning the specified acceptable fuel design limits are assumed to be met for this event when :
a.
The thermal margin limits (DNBR for PWRs and MCPR for BWRs) as specified in SRP Section 4.4 are met.
Framatome ANP, Inc.
SWJ :05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 1-2 b.
Fuel centerline temperatures (for PWRs) as specified in SRP Section 4.2 do not exceed the melting point.
c.
Uniform cladding strain (for BWRs) as specified in SRP Section 4.2 does not exceed 1%.
Although not identified in Reference 5, an additional failure criterion of 170 cal/g deposited enthalpy is provided in Section B3.3.1.1 of Reference 7 for fuel protection by the IRM for low power rod withdrawal events.
The impact on CPR was evaluated and determined not to challenge CPR limits in the 5 to 10 percent power range. At low powers the minimum critical power ratio (MCPR) is high and requires a substantial change to approach the MCPR safety limit.
In this analysis, the maximum DCPR/ICPR (delta CPR over initial CPR) was demonstrated to be less than that of other events.
The CPR could not be calculated for all conditions below 5% power in that the conditions were outside of the SPCB critical power correlation bounds. Therefore, comparisons of fuel enthalpy were made between the cases below 5% to that from the 30% power case. The peak pin fuel enthalpy of the cases below 5% power remained below the maximum value of the hot channel average enthalpy for the 30% power case.
In both conditions the flow is essentially at natural circulation and an increase in power results in an increase in flow. As such, the enthalpy comparison between the low power peak pin enthalpy and the hot channel average enthalpy at 30% power demonstrates that the critical power is not exceeded below 5% and criteria 2a is met below 5% power for the ganged RWE.
An evaluation of linear heat generation rate (LHGR) was completed at the beginning of cycle.
At 30 % power, the largest fraction of LHGR limit was 0.544 with a total peaking factor of 5.02.
A total peaking factor would have to be greater than 9 to approach the LHGR limit at 30%
power. As the power decreases, the total peaking factor would have to be even greater to approach the steady state LHGR limit.
An evaluation of the change in LHGR relative to the fuel design limit demonstrated that the greatest increase in nodal LHGR was less than 30% of the steady state LHGR limit. (Both Global Nuclear Fuels (GNF) and Framatome ANP, Inc.* (FANP) have proprietary limits for transients on the allowed increase in LHGR which are greater than this.) Therefore, the 1 Framatome ANP, Inc. is an AREVA and Siemens company.
Framatome ANP, Inc.
SWJ:05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 1-3 cladding strain limit is not exceeded and criteria 2c is met for operating power levels. The enthalpy deposition criteria identified in Reference 7 was also evaluated and it is shown that the IRM scram prevents enthalpies from exceeding the 170 cal/g criterion for ganged rod withdrawal.
Framatome ANP, Inc.
SWJ:05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 2-1 2.0
Background
Control rod withdrawal with the original reactor manual control system (RMCS) at the LaSalle Units was limited to a single control rod at a time. Implementation of the new rod control management system (RCMS) may allow the gang pull of control rods during startup. The control rod gangs are composed of groups of one to four rods which may be withdrawn simultaneously. Gangs are defined for both A and B sequence rod patterns. The gang definitions for the LaSalle Units and used in this evaluation are given in Figures 2.1 and 2.2.
The withdrawal of multiple control rods, i.e. gangs, results in more positive reactivity insertion into the core than a single control rod. However, the gangs are configured such that reactivity insertion is minimized. Gang withdrawal is standard for BWR-6 reactors which have a rod control system which enforces banked position withdrawal sequence (BPWS) during startup such that the low power rod withdrawal is not a credible event. The capability of the RCMS is similar in that BPWS will be enforced during reactor startup as well. The assumed BPWS withdrawal sequence used in this evaluation is provided in Table 2.1. This evaluation is performed to demonstrate that in the event a gang is erroneously withdrawn out of sequence the result will not challenge the fuel integrity. A failure mechanism is not identified as to how a gang could be erroneously withdrawn.
At low powers in the reactor startup mode, the IRM instruments provide a trip signal. The IRMs are configured into two groups for the purpose of generating trip signals. At any time one IRM per trip system group may be out of service. Therefore, the spatial dependence of the nearest operating IRM must be considered in the evaluation of the single rod withdrawal error.
However, when control rods are pulled in gang mode, the spatial dependence on functioning IRMs with respect to generating a trip signal is essentially eliminated. Figure 2.1 also provides a schematic of the location of the IRM instruments. The gangs are configured such that a control rod being withdrawn will be close to a working IRM. In addition to the evaluation of the LHGR and CPR response to the RWE, an evaluation of IRM responses to the simulated rod withdrawal error was included in the analysis. Although there are gangs defined which contain less than four rods, these gangs are located near the four central IRMs.
Framatome ANP, Inc.
SWJ :05 :014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 2-2 Frarnatorne ANP, Inc.
Table 2.1 Assumed Pull Sequence Following Group 4 Order Group End Position Order Group End Position 1
G07 4
12 G06 48 2
G08 4
13 G07 48 3
G07 6
14 G08 48 4
G08 6
15 G09 4
5 G07 8
16 G09 12 6
G08 8
17 G09 48 7
G07 12 18 G10 8
8 G08 12 19 G10G 48 9
G05 12 20 G10E 12 10 G05 48 21 G10F 12 11 G06 12
SWJ:05 :014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 2-3 59 55 51 47 43 39 35 31 27 23 19 15 11 7
3 G06B 1
G05A G01F 8
9 G06A G03 1 08C 17 18 19 G05B G01E G09D G02C 28 29 30 G05A G0111 146 147 G06A 159 G031 160 G05B 170
'08D 161 G01 F 171 G03G 2
G09E 10 G04D 20 G10F 150 G04E 162 G09F 172 G05D 3
G02E 11 G07F 21 G10E G01C 32 33 G01CIG09C 151 152 G07GIG03D 163 164 G02EIG10G 173 174 G06C G03G G05C G04F 179 180 181 182 G04F G05C G03G 4
5 6
G10G) G02DI G09F 12 13 14 G03CIG07GIG04D 22 23 24 G09C I G01 D I G1 0F 34 35 36 G01D G10E 153 154 G07F) 165 G02D 175 G05D 183 G04E 166 G09E 176 G03G 184 G06C 7
G01 F 15 G08D 25 G02C 37 G03 E'- 06A 26 27 G09D G01E G05A 38 39 40 G02C G09D G01E G05B 155 156 8 157 158 G08C G03 06A 167 168 169 G01 F G05A 177 178 G06B 185 2
6 10 14 18 22 26 30 34 38 42 46 50 54 58 IRM Framatome ANP, Inc.
Figure 2.1 LaSalle A-Sequence Gangs, Control Rod Numbers, and IRM Locations G06C G03F G08D G04C G07E G03B G08A G04A G08B G03B G07E G04C G08C G03F G06B 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 G01G G09F G02D G10F G01 B G09B G02A G10B G02B G09B G01A G10E G02E G09E G01G 56 57 58 59 60 61 62 3
63 4 64 65 66 67 68 69 70 G05C G04E G07G G03D G08B G04 07A G03 07B G04B G08A G03D G07F G04E G05D 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 G02F G10G G01D G09C G02B G10A G01A G09A G01B G10C G02A G09C G01C G10G G02F 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 G05D G04D G07F G03C G08A G04 5 07D G03 6 07C G04A G08B G03C G07G G04D G05C 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 G01G G09E G02D G10E G01B G09B G02A G10D G02B G09B G01A G10F G02E G09 F G01G 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 G06B GG2FIG083C 1
GO~ClG05E I G036AIG08B(G048B 1
G 8AIG 3 IG 7E IG 4C IG 8D IG 3 IG45
SWJ-05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 2-4 59 55 51 47 43 39 35 31 27 23 19 15 11 7
3 Framatome ANP, Inc.
G021 8
G03H G096 17 18 G02H G07G G01 D 28 29 30 G03J 1
G07H 9
04C
_19 GOSD 31 G06B 2
G01 E 10 G10E 20 G02E 32 G04E 3
G08G 11 G03F 21 G07E 33 G05A 4
G02G 12 G09F 22 G01C 34 G04F 5
G08F 13 G03G 23 G07D 35 G06AI G031 6
7 GOI F I G07H 14 15 G10E G04D 24
(
25 G02FIG08D 36 37 G02H 16 G09 03H 26 27 G01 D G07G G021 38 39 40 G021 G07G G01 D G08D 146 147 148 7 149 G0311i G09 04D 159 160 161 G02H G07H 170 G031 179 G02F 150 G10E 162 G01 F 172 G06A 180 G07D 151 G03G 163 G08F 173 G04F 181 G01 C 152 G09F 164 G02G 174 G05A 182 G07E 153 G03F 165 G08G 175 G04E 183 G02E 154 G10E 166 G01 E 176 G08D 155 G04C 167 G07H 177 G06B G03J 184 185 G01D G07G G02H 156 8 157 158 G09 03H 168 169 G021 178 Gang ID Rod #
2 6
10 14 18 22 26 30 34 38 42 46 50 54 58 Figure 2.2 LaSalle B-Sequence Gang Definitions G031 G09H G04D G10D G03E G09C G04A G10C G04B G09C G03E G10D G04C G09H G03J 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 G05B G01F G08E G02F G07C G01B G08B G02C G08A G01B G07C G02E G08E G01E G05A 56 57 58 59 60 61 62 63 4 64 65 66 67 68 69 70 G04F G10G G03G G09E G04B G10 3 03A G09 03C G10A G5-4A G09D G03F G10F G04E 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 G06A G02G G07F G01C G08C G02A G07A G01A G07B G02D G08C G01C G07F G02G G06A 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 G04E G10F G03F G09D G04A G10 5 03D G09 6 03B G10B G04B G09E G03G G10G G04F 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 G05A G01E G08E G02E G07C G01B G08A G02B G08B G01B G07C G02F G08E G01F G05B 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 G03J G09H G04C G10D G03E G09C G04B G10C G04A G09C G03E G10D G04D G09H G031 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145
SWJ :05 :014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 3-1 3.0 MCPR Evaluation The evaluation of MCPR was performed by establishing a critical rod pattern at 5% power intervals. Starting from the initial condition, all inserted gangs (excluding Groups 5 and 6) were then pulled simulating an error withdrawal. Evaluations were performed at beginning of cycle (BOC), peak hot excess reactivity (PHE), and end of cycle (EOC) for A-sequence and BOC for a B sequence rod pattern. The results, presented as a function of initial power, are provided in Tables 3.1 through 3.4 showing the gang withdrawal which resulted in the largest ACPR. In all cases the final CPR remained well above the MCPR safety limit. Graphical presentation of the results for all gang withdrawals for the A sequence are presented in Figures 3.1 through 3.3.
The B sequence results are shown in Figure 3.4. The conclusion remains unchanged in that the MCPR remains well above the safety limit for the ganged CRWE event.
For the BOC-A sequence, the single rod Gang G09A had the largest decrease in MCPR. This same trend is demonstrated for the BOC-B sequence withdrawals in that fewer rods in a gang results in larger change in MCPR. However, this change in CPR in response to the RWE is less than applicable plant transient limits. The maximum ACPR over initial CPR was less than 0.39 at 10% power. An operating limit of 1.82 is determined for a safety limit of 1.11 using the formulation of:
MCPROL = MCPRSL /I 1-ACPR I IMCPR This is bounded by the 25% power operating limit of 1.98 reported in Reference 6.
Framatome ANP, Inc.
SWJ :05 :014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 3-2 Framatome ANP, Inc.
Table 3.1 BOC A Sequence MCPR for Low Power CRWE Table 3.2 PHE A Sequence MCPR for Low Power CRWE Table 3.3 EOC A Sequence MCPR for Low Power CRWE Table 3.4 BOC B Sequence MCPR for Low Power CRWE Power (MCPR MCPR DMCPR Gan DMCPR/IMCPR 10 6.44 4.08 2.36 G09A 0.37 15 5.16 3.47 1.69 G09A 0.33 20 4.20 2.93 1.27 G09A 0.30 25 3.00 2.29 0.71 G09A 0.24 30 2.82 2.07 0.75 G09A 0.27 Power (MCPR MCPR DMCPR Gan DMCPR/IMCPR 5
9.99 5.49 NA 10 6.2 4.16 2.04 G09B 0.33 15 4.35 3.14 1.21 G09B 0.28 20 3.43 2.50 0.93 G09B/G09C 0.27 25 3.02 2.24 0.78 G09B/G09C 0.26 30 2.617H.98 0.63 G 10 F 0.24 Power (MCPR MCPR DMCPR Gang DMCPR/IMCPR 5
9.99 5.61 NA G09B 10 6.78 4.52 2.26 G09B 0.33 15 4.70 3.34 1.36 G09B 0.29 20 3.50 2.54 0.96 G09B 0.27 25 2.93 2.46 0.47 G09B 0.16 30 2.77 1.91 0.86 G09B 0.31 Power (MCPR MinCPR DMCPR Gang DMCPR/IMCPR 5
9.99 5.53 NA G09A 10 6.11 3.79 2.32 G09A 0.38 15 4.7 3.14 1.56 G09A 0.33 20 4.51 3.09 1.42 G09A 0.32 25 2.93 2.04 0.89 G09A 0.30 30 2.73 1.84 0.89 G09A~
0.33
SWJ :05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 3-3 0.45 0.40 0.35 0.30 0: v 0.25 f
a 0.20-0.15 0.10 0.05 0.00 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 Framatome ANP, Inc.
DMCPRIIMCPR versus Gang Worth BOC A-sequence (10-30% power)
Gang Worth mk Figure 3.1 DMCPR/IMCPR versus Gang Worth BOC A-Sequence A Gang G09A
- P10 XP15 o P20
" P25 O P30 i
O O
X O
O X X
x s
411 X
X
SWJ:05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 3-4 a 0.20 U
f a
a 0.35 0.30 0.25 0.10 0.05 DMCPR/IMCPR versus Gang Worth PHE A-sequence (10-30% power) 0.00 0.00 2.00 4.00 6.00 8.00 10.00 12.00 Framatome ANP, Inc.
Gang Worth mk Figure 3.2 DMCPR/IMCPR versus Gang Worth PHE A-Sequence s P10
~, P15
" P20
,X P25 O P30 O
1 O
x O
e x
f x
SWJ:05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 3-5 a
U a
a U
0 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Gang Worth mk Framatome ANP, Inc.
DMCPR/IMCPR versus Gang Worth EOC A-sequence (10-30% power)
Figure 3.3 DMCPR/IMCPR versus Gang Worth EOC A-Sequence I
10%
E15%
"20%
A25%
X 30%
AA A
D O
i X
.r
SWJ:05 :014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 3-6 a
U a
U 0
0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Framatome ANP, Inc.
DMCPR/IMCPR versus Gang Worth BOC B-sequence (10-30% power)
Gang Worth mk Figure 3.4 DMCPR/IMCPR versus Gang Worth BOC B-Sequence O4 Rod Gangs
" 2 Rod Gangs
'-s-in-91-e-Rod Gang a
i a,
~
o 0
0~ 0 0
o 0 0 0 0
0 0
0 0 4
0 0 0
m 16 0
8 0 60
SWJ:05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 4-1 4.0 LHGR Evaluation The change in LHGR was evaluated to verify the 1 % strain criterion is not exceeded. The evaluation of LHGR was performed at the beginning of cycle. At 30% power, the largest fraction of LHGR limit was 0.544 with a total peaking factor of 5.02. A total peaking factor would have to be greater than 9 to approach the LHGR limit at 30% power. As the power decreases, the total peaking factor would have to be even greater to approach the steady state LHGR limit.
An evaluation of the change in LHGR relative to the fuel design limit demonstrated that the greatest increase in nodal LHGR was less than 30% of the steady state LHGR limit. (Both GNF and FANP have proprietary limits for transients on the allowed increase in LHGR which are greater than 30% for rod withdrawal.) Therefore, the 1 % cladding strain limit is not exceeded and criteria 2c is met. Figure 4.1 identifies the maximum fraction of the steady state LHGR limit for the various gang withdrawals at various power levels. Figure 4.2 identifies the maximum value of the nodal change in LHGR divided by the LHGR limit. As Figure 4.2 indicates, the maximum change in LHGR is less than 0.30 of the LHGR design limit.
Framatome ANP, Inc.
SWJ:05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 4-2 0.6 0.5 0.4 c
0 u 0.3 0.2 0
Fraction of LHGR Limit Base G07E f G07F G07G G08A G08B G08C G08D G09A G09B G09C G09D G09E G09F G10E G10F G10G Gang Framatome ANP, Inc.
Figure 4.1 Maximum Fraction of Limit for LHGR
+--P05
---G-Pi 0 I*
-P15 P20 i-* -
P25 r
SWJ :05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 4-3 0.35 0.30 0.25 0 0.20
- u. m G 0.15 0.10-0.05 -
0.00 Framatome ANP, Inc.
Delta Fraction of LHGR Limit G07E G07F G07G G08A G08B G08C G08D G09A G09B G09C G09D G09E G09F G10E G10F G10G Gang Figure 4.2 Maximum Delta LHGR Divided by LHGR Limit
--t--P05
--U-Pi 0
-tl-P15
~~
P20 P25
--~-- P30
SWJ :05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-1 5.0 Enthlapy Evaluations The RAMONA5-FA code is a transient code used to evaluate the time-dependence of the RWE.
The code was first used to repeat the RWE cases performed with MICROBURN-B2. It was then used to evaluate fuel enthalpy and IRM responses at power levels below 5% power. The gangs selected for evaluation below 5% power are given in Table 5.1.
The hot channel average enthalpy was determined for the withdrawals at 30% power and is shown in Figure 5.1. The enthalpy values for 30% power cases are used for relative comparisons with low power RAMONA results.
The highest gang worths were selected from each inserted group. Groups 5 and 6 and those Gangs comprised of a single control rod were excluded from this selection process with the exception of Gang G09A. At 5% power, only Gangs G09A and G09B were evaluated.
A local peaking factor of 2.0 was used for the evaluation of peak pin enthalpy. This value conservatively bounds the actual local peaking and results in a higher pin temperature and enthalpy. The peak pin and channel enthalpies for the rod withdrawal at BOC A sequence are given in Table 5.2. All enthalpies are less than the maximum hot channel average enthalpy shown in Figure 5.1. The fuel enthalpies for PHE and EOC for the A sequence are given in Tables 5.3 and 5.4. The peak pin channel enthalpies during the transients are shown in Figures 5.2 through 5.4 for the BOC A sequence rod withdrawals. The maximum hot channel average enthalpy from Figure 5.1 is also included in Figures 5.2 through 5.5. These figures show that the enthalpy for the hottest pin for the low power withdrawal was less than the average hot channel enthalpy of the 30% power case.
An evaluation of the IRM response was included in the evaluation to demonstrate that the IRM system would preclude the adiabatic enthalpy from exceeding 170 cal/g as indicated in Reference 7. The evaluation of the IRM response assumed that the IRMs were at 10% of scale prior to the RWE and a trip would occur at 120% of scale or an increase in the flux level by a factor of 12.
Gangs G09C, G09D and G10G were selected for evaluation of the IRM response for a single rod withdrawal versus a gang withdrawal. Control rod 87 (R087) was selected for single rod withdrawal evaluation from Gang G1 0C, control rod 89 from Gang G09C, and control rod 156 (R156) from Gang G09D. These calculations were initiated from 0.2% power to demonstrate the Framatome ANP, Inc.
SWJ:05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-2 IRM response and trip function. The peak pin enthalpies for these withdrawals are provided in Figure 5.5. The IRM responses during the pull of R156 from Gang G09D are given in Figure 5.6. The IRM responses during the pull of Gang G09D are given in Figure 5.7.
The peak pin enthalpy of the withdrawal of Gang G09C (four rods) is only slightly higher than that of the single rod 89. The enthalpy is well below challenging fuel integrity limits compared to the enthalpy of the 30% power case (Figure 5.1).
For Gang G09D, the peak pin enthalpy of the four rod case is consistent with the single rod case R156. Withdrawal of Gang G09D would result in an IRM initiated trip since several IRMs increase by a factor of 12. An IRM trip cannot be assumed for the single rod R156 in that single IRM which detected the flux increase by a factor of 12 could be bypassed. For this example the resultant peak pin enthalpy is greater for single rod than for the gang withdrawal since the gang RWE would be terminated by the IRM trip.
A scram would be initiated for the four rod Gang G10G and the peak pin enthalpy remains below that of withdrawal of R087 which would not initiate a scram.
The adiabatic enthalpies for the cases which scrammed are provided in Table 5.5. The enthalpy results reported are considerably less than the 170 cal/g criterion identified in Reference 7.
Framatome ANP, Inc.
SWJ:05 :014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-3 Framatome ANP, Inc.
Table 5.1 BOC A Sequence Rod Withdrawal Below 5% Power Table 5.2 Relative Peak Fuel Enthalpies from Rod Withdrawal Error Gano
_ - " "gulls at 63% rod dentis Gang" Worth mk Gang Worth mk G03B 12.45 G04A 6.66 G04A 11.69 G07G 13.56 G07G 17.03 G08A 14.96 G08B 17.84 G09C 19.50 G10G 18.17 G10G 15.48 Peak Pin Peak Channel Case cal/g cal/g bocA G02 GO3B 24.37 20.40 bocA G02 GO4A 23.34 19.97 bocA G02 GO7G 24.37 20.47 bocA G02 GO8B 24.84 20.74 bocA G02 G10G 26.76 21.57 bocA G03 GO4A 22.60 19.59 bocA G03 GO7G 25.80 21.17 bocA G03 GO8A 26.52 21.48 bocA G03 GO9C 28.19 22.22 bocA G03 G10G 27.47 22.00 bocA P05 GO9A 35.12 25.56 bocA P05 GO9B 29.38 22.89
SWJ-05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-4 Table 5.3 Relative Peak Fuel Enthalpies and Rod Worths for PHE A Sequence Rod Withdrawal Error Framatome ANP, Inc.
Peak pin Peak Channel Worth Enthalpy Enthalpy Case Initial Group Gang mk cal/g cal/g pheA G02 GO3B 1 and 2 at 48 G03B 11.12 25.32 20.86 pheA G02 GO4D 1 and 2 at 48 G04D 11.35 24.61 20.62 pheA G02 GO7F 1 and 2 at 48 G07F 18.18 27.23 21.74 pheA G02 GO7G 1 and 2 at 48 G07G 18.31 27.23 21.74 pheA G02 GO8A 1 and 2 at 48 G08A 16.90 27.23 21.64 pheA G02 GO8B 1 and 2 at 48 G08B 17.12 27.23 21.72 pheA G02 G09B 1 and 2 at 48 G09B 17.45 27.47 21.76 pheA G02 GO9C 1 and 2 at 48 G09C 19.10 27.47 21.98 pheA G02 G1OF 1 and 2 at 48 G10F 15.39 26.52 21.40 pheA G03 GO7F 1, 2 and 3 at 48 G07F 15.86 28.19 22.12 pheA G03 GO7G 1, 2 and 3 at 48 G07G 16.24 28.19 22.15 pheA G03 GO8A 1, 2 and 3 at 48 G08A 15.57 28.19 22.07 pheA G03 GO8B 1, 2 and 3 at 48 G08B 15.59 28.19 22.12 pheA G03 GO9B 1, 2 and 3 at 48 G09B 15.61 28.43 22.12 pheA G03 GO9C 1, 2 and 3 at 48 G09C 23.22 30.58 23.58 pheA G03 G1OF 1, 2 and 3 at 48 G10F 13.93 27.47 21.72 pheA P05 GO8B 1, 2, 3 and 4 at 48 G08B 11.57 30.10 23.36 pheA P05 GO9B 1, 2, 3 and 4 at 48 G09B 11.66 30.58 23.58
SWJ :05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-5 Table 5.4 Relative Peak Fuel Enthalpies and Rod Worths for EOC A Sequence Rod Withdrawal Error Framatome ANP, Inc.
Table 5.5 Adiabatic Enthalpy Results Peak pin Peak Channel Worth Enthalpy Enthalpy Case Initial Group Gang mk cal/g cal/g eocA G02 G08C 1 and 2 at 48 G08C 27.60 30.10 23.20 eocA G02 G08D 1 and 2 at 48 G08D 27.71 29.86 23.20 eocA G02 G09E 1 and 2 at 48 G09E 23.69 27.95 22.22 eocA G02 G09F 1 and 2 at 48 G09F 22.65 27.47 22.00 eocA G03 G08C 1, 2 and 3 at 48 G08C 26.35 33.92 24.84 eocA G03 G08D 1, 2 and 3 at 48 G08D 25.99 33.92 24.84 eocA G03 G09C 1, 2 and 3 at 48 G09C 19.76 32.73 24.13 eocA G03 G09D 1, 2 and 3 at 48 G09D 19.74 31.77 23.53 eocA P05 G08B 1 -4 at 48 G7 at 4 G08B 9.06 36.79 26.28 eocA P05 G08C 1 -4 at 48 G7 at 4 G08C 8.39 37.74 26.99
SWJ :05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-6 50.00 45.00 40.00 35.00 30.00 a 25.00 t
c 20.00 15.00 10.00 5.00 0.00 Hot Channel Average Pin Enthalpy 0
5 10 15 20 25 30 35 40 45 50 Time (s)
Framatome ANP, Inc.
Figure 5.1 Hot Channel Average Enthalpy for Rod Withdrawal at 30%
Power G09A
-~- G098
Low Power CRWE Evaluation for LaSalle Rod Control Management System 50.00 45.00 40.00 35.00 30.00 c 25.00 20.00 15.00 10.00 5.00 0.00 0
10 20 30 40 Time (s)
Framatome ANP, Inc.
Hot Pin Enthalpy for G02 Gang Withdrawals 50 60 Figure 5.2 Hot Pin Enthalpy for Gang Withdrawals Starting from 75%
Rod Density SWJ :05:014 Revision 0 Page 5-7
~-
G03B
-~- G04A G07G
~~
G08B 0
G10G P30
SWJ:05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-8 Hot Pin Enthalpy for G03 Gang Withdrawals 0
10 20 30 40 50 60 Time (s)
Framatome ANP, Inc.
Figure 5.3 Hot Pin Enthalpy for Gang Withdrawals Starting from 63%
Rod Density
SWJ:05 :014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-9 50.00 45.00 40.00 35.00 30.00 m
a 25.00 m
t c
w 20.00 15.00 10.00 5.00 0.00 0
10 20 30 40 50 60 Time (s)
Framatome ANP, Inc.
Hot Pin Enthalpy for P05 Gang Withdrawals Figure 5.4 Hot Pin Enthalpy for Gang Withdrawals Initiated at 5%
Power G09A
-- N -
G09B P30
SWJ :05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-10 50.00 45.00 40.00 35.00 30.00 a 25.00 m
L C
w 20.00 15.00 10.00 -
5.00 0.00 0
10 20 30 40 50 60 Time (s)
Framatome ANP, Inc.
Hot Pin Enthalpy for G12 Cases Figure 5.5 Hot Pin Enthalpy for Withdrawals Initiated at 0.2% Power 0
G09C
-~- G09D
- --G10G
-X-G10G-RO87
-alt-- G09C-R089
-v-G09D-156 P30
SWJ:05 :014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-11 1.00E+14 1.00E+13
- u.
1.00E+12 1.00E+11 1.00E+10 Framatome ANP, Inc.
IRM Response for Rod 156 0
4 9
14 19 24 29 34 39 Time (s)
Figure 5.6 IRM Signal Responses for Withdrawal of Rod 156 IRM1
--w-- I RM2 e IRM3
- -- IRM4
- - IRM5
-~- IRM6
+
IRM7 IRM8
SWJ:05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 5-12 1.00E+14 1.00E+13 1.00E+12 1.00E+11 1.00E+10 Framatome ANP, Inc.
Gang G09D IRM Response 0
5 10 15 20 25 30 35 40 45 50 Time (s)
Figure 5.7 IRM Signal Responses for Withdrawal of Gang G09D
-+-IRM1
-- IRM2
-a-- IRM3
-~E-IRM4
-->~- IRM5
-~- IRM6
-t-IRM7 IRM8
SWJ :05:014 Low Power CRWE Evaluation for Revision 0 LaSalle Rod Control Management System Page 6-1 6.0 References 1.
LaSalle County Station UFSAR Revision 15, April 2004.
2.
EMF-2158(P)(A) Revision 0, Siemens Power Corporation Methodology for Boiling Water Reactors: Evaluation and Validation of CASMO-41MICROBURN-B2, Siemens Power Corporation, October 1999.
3.
EMF-3028(P) Volume 1, Revision 0, RAMONA5-FA : A Computer Program for BWR Transient Analysis in the Time Domain Volume 1 : User's Manual, Framatome AN P
September 2004.
4.
EMF-3028(P) Volume 2, Revision 0, RAMONA5-FA : A Computer Program for BWR Transient Analysis in the Time Domain Volume 2 : Theory Manual, Framatome ANP, October 2004.
5.
NUREG-0800, NRC : Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants, SRP 15.4.1 `Uncontrolled Control Rod Assembly Withdrawal from a Subcritical or Low Power Startup Condition', Draft Rev. 3, April 1996.
6.
EMF-2830 Revision 1, LaSalle Unit 2 Cycle 10 Reload Analysis, Framatome ANP, April 2003.
7.
NUREG 1433 Revision 3.0, Standard Technical Specification General Electric Plants, BWR14, June 2004 Framatome ANP, Inc.
Low Power CRWE Evaluation for SWJ :05 :014 LaSalle Rod Control Management System Revision 0 Framatome ANP, Inc.
Distribution Controlled Distribution Richland R. J. DeMartino S. W. Jones P. D. Wimpy E-Mail Notification O. C. Brown D. M. Carr J.
L. Maryott C. M. Powers D. R. Todd