ML20084R100
| ML20084R100 | |
| Person / Time | |
|---|---|
| Site: | 05200003 |
| Issue date: | 05/31/1995 |
| From: | WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP. |
| To: | |
| Shared Package | |
| ML20084R068 | List: |
| References | |
| NUDOCS 9506090183 | |
| Download: ML20084R100 (83) | |
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DRAFT A. MAAP4 Analyses to SIpport Success Criteria APPENDIX A l
MAAP4 ANALYSIS TO SUPPORT SUCCESS CRITERIA A.1 Introduction The success criteria that define the event tree paths that do not result in core damage have been identified and discussed in Chapter 6. Supporting analyses for the success criteria and success paths can sometimes be found within the licensing basis analyses in the Standard Safety Analysis Report (SSAR). However, when there are multiple system failures, other analyses are necessary to support the success criteria definitions. Most of the success paths involve multiple failures and include the actuation of the automatic depressurization system (ADS). The additional system analyses are performed with the Modular Accident Analysis Program, version 4.0 (MAAP4) and are described in the following subsections.
A.l.1 MAAP4 Overview and Limitations MAAP4 is a computer code that simulates the response of light water reactor systems to initiating events. It was originally developed to investigate the physical phenomena that may occur in the event of a severe accident after significant core damage. Although the emphasis in the code development has been on the severe fuel damage phase of the accident, the code can also be used to predict the thermal-hydraulic behavior prior to cote damage.
MAAP4 is a fully integrated, systems accident code and includes models for importsnt thermal-hydraulic and fission-product phenomena which may occur during a postulated accident in a pressurized water reactor plant. The models in MAAP4 relevant to success criteria are the following:
Reactor coolant system thermal-hydraulics Cladding water reaction Reactor core heatup
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Containment thermal-hydraulics
'Ihe version of MAAP4 used for these analyses is documented in Reference A-1, which provides details of the code models, the benchmarking performed, and users guidance.
MAAP4 has improved capability, compared to MAAP3B, to model the following in-vessel and advanced reactor systems:
Detailed core model nodalization includes the fuel, clad, control rod and coolant. Up
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to 175 nodes can be modelled; the AP600 model has 85 nodes, with 5 radial rings and 17 axial rows.
Improved pressurizer and surge line thermodynamic calculations for modeling the large valves used in the automatic depressurization system May 31,1995
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9506090183 950531 PDR ADOCK 05200003 PDR A
DRAFT A. MAAP4 Analyses ta Srpport Success Criteria Generalized containment model
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Passive safety system models, including passive residual heat removal (PRHR) heat exchanger, core makeup tanks (CMTs), and passive containment cooling system (PCS)
MAAP4 was chosen as the code to support the success criteria because ofits flexibility and ease of use. MAAP4 integrates the effects from the primary system, the secondary system, and the containment. 'Ihe code is fast-running, making it feasible to analyze a large number of scenarios, variations of the scenarios, and sensitivities. The flexibility of the code includes the capability to model a wide range ofinitiating events and the capability to model operator intervention based on times or " trigger" events.
When applied to pre-core damage success criteria analyses, MAAP4 has limitations due to the model simplifications that make MAAP4 a fast-running code. The model simplifications have been considered in the analyses and are discussed below.
Core Power The core power in MAAP4 is based on the full power input value before the reactor trips, and 1979 ANS decay heat after the reactor trips. The MAAP4 core power model is an adequate best estimate prediction of the core heat for the majority of the accident scenarios.
MAAP4 does not have a neutronics model and, therefore, cannot be used to determine the short-term reactivity transients or the potential for return to power after reactor trip that can be a concern for transients. Therefore, MAAPL is only used for the longer thermal-hydraulic system response in transients, and is not used for anticipated transient without scram (ATWS) events.
For loss-of-coolant-accident (LOCA) initiating events, the plant remains at steady-state full power conditions until sufficient coolant inventory is lost through the break to cause the reactor to trip on a low pressurizer level or low pressurizer pressure signal. Since any make-up flow to the reactor coolant system (RCS)is borated, there are no power excursion concerns for loss-of-coolant accidents. For most loss-of-coolant accidents, the reactor trips within the first minutes of the accident and the core power model is based on decay heat. However, for small breaks in the reactor coolant system, the reactor can remain at full power on the order of 10 minutes until a reactor trip signal is reached. The absence of a neutronics model in MAAP4 is not a concern because power excursions are not a part of the expected plant response for the cases modelled with MAAP4.
Core Heat Transfer There are also limitations for loss-of-coolant accident events, if the break is large and depletes the reactor coolant system inventory rapidly. MAAP4 can not handle the oossibility of exceeding the critical heat flux during the blowdown, nor can it handle reflood while considerable stored heat remains within the fuel. If core uncovery occurs after the initial stored energy in the core has been removed, and the core heat is down to decay heat levels, the code simplifications do not significantly impact the results (Reference A-2). Therefore, May 31,1995 A-2 ym.
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i DRAFT A. MAAP4 Analyses to Support Success Criteria for " smaller" break sizes that do not involve a competition between reflood and clad heat-up rates, MAAP4 calculations are good at predicting the system response. As a result, the cede is not used to analyze large loss-of-coolant accidents.
Two-Phase Flow Model To maintain MAAP4 as a relatively small, fast-running code, the treatment of two-phase (water and steam) natural circulation in the primary system has been simplified. A thorough i
model would include the detailed treatment of void fraction distribution, a non-equal velocity model, and detailed pressure distribution through the reactor coolant system. Instead, a much simpler model was adopted for MAAP4, in which the primary system is assumed to have a spatially constant, homogeneous void fraction until phase separation occt,rs.
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When the reactor coolant pumps (RCPs) are running, the voids are assum x1 to be uniformly distributed throughout the reactor coolant system. When the reactor coolant pumps are tripped, the MAAP4 model includes two options; natural circulation may be assumed, with the voids uniformly distributed; or the phases may be assumed to instantly separate into a stable gas-over-water configuration. The determination of which assumption is made is controlled by a user input, VFSEP. If the average void fraction is smaller than VFSEP, natural circulation is assumed, while the gas-over-water assumption occurs if the void fraction is greater than VFSEP.
Prior to phase separation, the homogeneous natural circulation model may not accurately predict the details of the internal situation in the reactor coolant system. T&H benchmarking of MAAP3B (Reference A-2) found little sensitivity to the value of VFSEP. However, sensitivity analyses on the value of VFSEP are performed in Section A.8.
Ilreak Flow Model The break flow rate in MAAP4 is determined by considering the pressure difference across the break, the fluid properties, and the void fraction entering the break. When the break location is totally submerged, the void fraction is based on the reactor coolant system void fraction. When the break location is partially submerged, the M ^AP4 model considers the entrainment of the liquid into the overlying gas. The entrainment model is limited to only considering the entrainment ofliquid that is contained within the break node. Therefore, the MAAP4 break model is not sufficient to address large breaks in the reactor coolant system ir..ehich the entrainment of water would extend beyond the immediate break location. As a result, tne code is not used to analyze large loss-of-coolant eccidents.
A.1.2 MAAP4 Model for AP600 The AP600 MAAP4 model is defined in a parameter file and an input deck. The parameter file contains the majority of the AP600 model, while the input deck is used to model the event-specific parameters. In addition, the input deck can be used to supersede any input in the parameter file, so that sensitivity studi:s can easily be performed. The purpose of this W Westinghouse Mm A,
DRAFT A. MAAP4 Analyses to Srpport Success Criteria section is to identify the general assumptions and models that are consistent in all of the analyses to support the success criteria.
The AP600 systems for core heat removal and reactor coolant system coolant inventory replacement that are modelled in MAAP4 are the steam generators, the passive residual heat removal, the core makeup tanks, the accumulators, gravity draining of the in-containment refueling water storage tank (IRWST), and the normal residual heat removal system (RNSL The steam generators and accumulators are a part of the MAAP4 model for conventional plants. The core makeup tank, passive residual heat removal and in-containment refueling water storage tank models were added to the general version of MAAP4 specifically for AP600. The normal residual heat removal model was added to the MAAP4 parameter file by defining low-pressure injection pumps drawing suction from the in-containment refueling water storage tank. The normal residual heat removal model does not take credit for any heat exchanger, which is a reasonable assumption for the limited time frame considered in these analyses. Startup feedwater and CVS are heat removal and inventory makeup sources that are not generally credited in the MAAP4 analyses.
All success criteria analyses with MAAP4 are terminated after a long term injection source is established to restore and maintain coolant inventory for the removal of decay heat.
All analyses include the consideration of the passive containment cooling system (PCS). For cases that rely on gravity injection from the in-containment refueling water storage tank, the time that the injection begins and the flow rate of the injection are a function of containment pressure. Therefore, a lower containment pressure is more limiting, and the operation of the passive containment cooling system is included in all the analyses. A lower containment pressure may also occur due to a failure in containment isolation. But this is not an assumption made in all the MAAP4 analyses since containment isolation is most likely to function as designed. However, the failure of containment isolation is considered in the definition of the success criteria through sensitivity analyses (Sections A.8 and A.9).
Because these analyses are to support the system response, the actuation signals and setpoints of the protection systems can be important to the timing and outcome of the results.
Table A-1 summarizes the signals and other assumptions for the reactor trip, reactor coolant pump trip, automatic depressurization system actuation, core makeup tank actuation, accumulator actuation, passive residual heat removal actuation, normal residual heat removal operation, and the in-containment refueling water storage tank gravity drain.
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A. MAAP4 Analyses to S:pport Success Criteria A.1.3 MAAP4 Analysis Objectives and Considerations ne MAAP4 analyses identify the configurations and timing for automatic depressurization system, core makeup tanks and accumulators, passive residual heat removal, and normal residual heat removal and in-containment refueling water storage tank gravity drain that result in sufficient core heat removal and inventory control to prevent core damage. R ese configurations and timings constitute the success criteria for a given set of event sequences.
The initiating events are grouped into five categories for the MAAP4 analyses, as discussed in Section A.2. The break sizes for the loss-of-coolant accident initiating events are defined in Section A.3.
The definition of the MAAP4 cases focus on the automatic depressudzation system success criteria, as discussed in Section A.4. De automatic depressurization system success criteria are also considered with respect to whether the reactor coolant system depressurization is partial or full, and whether the automatic depressurization system lines are automatically or manually opened. Partial depressurization is defined as reducing the reactor coolant system pressure below the normal residual heat removal pump shut off head (~ 175 psia). Full depressurization is defined to be the condition at which the in-containment refueling water storage tank gravity drain can perform the long term injection and heat removal function.
Automatic versus manual actuation of the automatic depressurization system is dependent on whether a core makeup tank is credited in the event sequence. A low core makeup tank level is the only signal that automatically actuates the automatic depressurization system, and therefore manual actuation of the automatic depressurization system is credited as a potential success path if no core makeup tanks successfully inject.
A.1.4 Systematic MAAP4 Analysis Methodology The MAAP4 analyses to support the success critata definitions are selected in a manner that adequately represents the applicable scenarios. To verify any given success criterion, both the initiating event and the system assumptions for the event tree sequence are considered. For each path on the event trees, conservative representative sequences, called baseline sequences, which do not result in core damage determine the success configuration for the systems. The definitions of baseline sequences and core damage are provided below. The steps in the systematic methodology are:
define a success configuration for t>1e event tree path define a baseline sequence to represent the event tree path
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perform MAAP4 analysis for the baseline sequence determine margin to core damage
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perform sensitivity analyses if insufficient margin exists e
redefine success configuration if necessary, and repeat process to obtain margin.
e The details of the methodology are outlined in this section. Figure A-1 presents a flowchart of the methodology.
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mamma DRAFT A. hfAAP4 Analyses to Szpport Success Criteria A.I.4.1 Baseline Sequences To determine any given success criterion, the initiating event and the hardware and human action assumptions on the event tree are considered. Analyses consider the operation of plant systems, even those not modeled on the event tree, that could adversely impact the response to the sequence. An example of this consideration is the containment isolation system.
Although not included on the event trees, the failure of the containment isolation system makes gravity injection from the in-containment refueling water storage tank more difficult to achieve (see section A.8.2). Therefore, the failure of the containment isolation system is included in gravity injection MAAP4 baseline sequence analyses.
A baseline sequence is one which includes the worst-case configuration associated with the variabilities in the event tree path to which the success criterion applies. Such variabilities exist because each path shown on an event tree actually represents additional possible hardware / human action combinations which have been bounded by the modeled sequence as a result of practical considerations for quantifying the PRA. These variabilities are:
minimum injection capability defined for the path
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passive residual heat removal availability defined for the path
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worst break size for the initiating event worst break location in the reactor coolant system for the initiating event
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longest credited operator action time for manual actions
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containment isolation failure and passive containment cooling water success Minimum Injection. The minimum injection is typically defined by the event tree path that the baseline sequence represents. Short-term injection can be provided by the two core makeup tanks and the two accumulators. Either one core makeup tank or one accumulator is credited for each path on the event tree. An accumulator is only credited in the paths with the failure of both core makeup tanks (except for Large LOCA which is not analyzed with the MAAP4 code or this methodology). Therefore, one core makeup tank or one accumulator is modeled in a baseline sequence.
Long-term injection can be provided by either the two normal residual heat removal (RNS) pumps or by the two lines of in-containment refueling water storage tank (IRWST) gravity injection. Event tree paths credit one RNS pump in the event that the primary system is not fully depressurized for gravity injection. If the reactor conlant system is fully depressurized, the event tree path credits either one RNS pump or one IRWST injection line. For partial depressurization, one normal RHR pump is modeled in the baseline sequence. For full depressurization, one IRWST injection line is modeled in the baseline sequence. The success of RNS in the fully depressurized case is bounded by the partially depressurized baseline sequence.
Passive Residual lleat Removal (PRIIR). The availability of the passive RHR is defined by the event tree path modeled in the baseline sequence. One PRiiR heat exchanger is credited for paths with PRHR success.
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DRAFT A. MAAP4 Analyses to S:pport Success Criteria Worst Break Size. De worst break size for the success configuration cannot be directly discerned. The break size affects the timing of the sequence and decay heat considerations, reactor coolant system depressurization, and spillage of the injection. Therefore, supporting analyses are performed which vary the break size to determine the worst break size for the baseline sequences.
Worst Break Location. The worst break location cannot be directly discerned. The break location affects the elevation of the break, and pressurizer flooding. In LOCAs this can produce small effects in the reactor coolant system pressure and affect the gravity injection.
Therefore, supporting analyses varying the break location are performed for gravity injection baseline LOCA sequences.
Operator Action Timing. For manual actuation sequences such as failure of the core makeup tanks which require manual action for reactor coolant system depressurization, the maximum time for operator action credited in the event trees is included in the baseline sequence. For systems that are normally actuated automatically but in which credit is taken for a backup manual actuation if the automatic actuation fails, sensitivity cases to the baseline case are performed to show timing limitations.
Containment Isolation and Passive Containment Cooling Water. The operauon of the containment isolation and passive containment cooling water can affect gravity injection by creating small increases in the pressure differential between the reactor coolant system and the containment. At lower containment pressures it is more difficult to achieve successful gravity injection. Therefore, for baseline sequences that credit gravity injection for long-term heat removal, containment isolation is not credited and passive containment cooling water is I
credited to reduce the containment pressure. This assumption does not apply to nonnal residual heat removal baseline sequences. Normal RHR is a pumped system and is not affected significantly by small changes in the differential pressure between the containment and the reactor coolant system.
A.1.4.2 Core Damage Definition Based on Reference A-3, the core is considered to be damaged if both of the following i
conditions occur:
l The collapsed water level in the reactor has decreased such that active fuel in the core has been uncovered.
A fuel cladding temperature of 2200*F (1477'K) or higher is reached in any node of the core as defined in a best-estimate thermal hydraulic calculation.
The criterion refers to the peak clad temperature. The clad temperature is not a parameter that is easily summarized in MAAP4 output, and therefore the core temperature is presented for j
I these analyses. At the start of the event when the reactor is at full power, the core temperature is approximately 260'F (400*K) higher than the clad temperature. By 500 seconds after reactor trip, the difference is on the order of tens of degrees, with the core
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DRAFT A. MAAP4 Analyses to Scpport Success Criteria l
temperature being a slight over-estimation of the clad temperature. The plots of the core temperature response are of interest after the initial cooldown from the reactor trip. If there is no core uncovery during the accident, no peak temperature is reported in Section A.4 or A.9 for that case.
Although a limit of 2200*F is acceptable and the calculation can be made on a best estimate l
basis, " success" in the MAAP4 analyses occurs at a substantially lower temperature. When there is significant clad oxidation, the heatup rate of the core is increased. Clad oxidation l
begins at 1490'F (1083*K), but has only a minor impact on the heatup rate until approximately 1700*F (1200'K). To demonstrate margin to core damage, baseline sequence peak core temperatures after core uncovery are shown to be less than 1350'F (1000*K). Since the low probability baseline sequence produces the highest peak temperature, this approach provides substantial margin in terms of both the peak temperature and the probability of producing elevated core temperatures.
A.I.4.3 Sensitivity Analyses If the peak temperature of the baseline sequence is greater than 1350'F (1000'K), sensitivity analyses are performed on the baseline sequence to demonstrate that the temperature will not increase to greater than 2200*F (1477'K) for reasonable changes in plant parameters which affect the performance of the hardware credited in the sequence. Code parameters and thermal-hydraulic uncertainties for the baseline sequences are addressed as a separate issue and with a more rigorous treatment elsewhere and are not addressed in these analyses. The plant parameter sensitivity analyses are performed varying the parameters one-at-a-time.
Combinations of sensitivities are oflow probability and are not performed in these analyses.
The plant parameters which are considered for sensitivity analyses are listed below:
automatic depressurization system minimum flow i
core makeup tank minimum flow
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accumulator minimum flow
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passive residual heat removal minimum heat removal
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normal residual heat removal injection minimum flow in-containment refueling water storage tank gravity injection minimum flow.
i Automatic Depressurization System (ADS). The flow requirements for the ADS system are l
defined in the design basis analyses and are controlled by inspection, testing and acceptance criteria (ITAAC). The MAAP4 parameters for the ADS valve areas are input as the minimum equivalent areas per the ADS requirements. Therefore, no additional sensitivities are performed on the ADS flows.
t Core Makeup Tanks (CMT). The flow requirements for the CMT are defined in the design basis analyses and are controlled by inspection, testing and acceptance criteria (ITAAC). The MAAP4 parameters for the CMT are input to calculate best-estimate flow. CMT parameters 1
are adjusted to calculate minimum flow for applicable baseline sequence sensitivity analyses.
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DRAFT A. MAAP4 Analyses 13 Scpport Success Criteria Accumulators. The flow requirements for the accumulators are defined in the design basis analyses and are controlled by inspection, testing and acceptance criteria (ITAAC). The MAAP4 parameters for the accumulators are input to calculate best-estimate flow.
Accumulator parameters are adjusted to calculate minimum flow for applicable baseline sequences.
Passive Residual Heat Removal (PRHR). The heat removal requirements for the PRHR are defined in the design basis analyses and are controlled by inspection, testing and acceptance criteria (ITAAC). The MAAP4 parameters for the PRHR are input to calculate the best-estimate heat removal. The PRHR parameters are adjusted to calculate minimum heat removal for applicable baseline sequences.
In-Containment Refueling Water Storage Tank (IRWST) Gravity Injection. The flow requirements for the IRWST gravity injection are defined in the design basis analyses and are controlled by inspection, testing and acceptance criteria (ITAAC). The MAAP4 parameters for the IRWST gravity injection are input to calculate best-estimate flow. Gravity injection parameters are adjusted to calculate minimum flow for applicable baseline sequence sensitivity analyses.
1 A.2 Initiating Events The event trees, as described in Chapter 4, are structured to identify the accident sequences that may occur following each internal initiating event. For the MAAP4 analyses, the initiating events are grouped into five event categories. This process is necessary to limit the number of MAAP4 cases to consider. However, the events are grouped in a manner that does not lose any of the important detail of the event tree success paths analyzed with MAAP4.
The five initiating event categories for the MAAP4 analyses are medium loss of coolant (MLOCA), intermediate loss of coolant (NLOCA), small loss of coolant (SLOCA), steam generator tube mpture (SGTR), and transient. All of the event trees fit into these categories except LLOCA, ISLOCA, vessel rupture, and ATWS; the success criteria for these initiating events are not addressed with MAAP4 analyses.
'Ihe following sections contain information on each of the initiating event categories. This includes a list of the a;)plicable event trees and a discussion of the success criteria and success paths that are addressed by the MAAP4 analyses. The basis for grouping the event trees is provided by identifying the similarities and differences in the success paths.
This section only includes the rationale for the grouping of the events. Results from each of the initiating events are summarized in Section A.9.
Throughout the remainder of Appendix A, initiating events are referred to by the grouping established within this section.
For example, the events that are initiated without a break in the reactor coolant system are referred to as " transient," without any reference to the specific event tree. Whether the initiating event was a loss of feedwater or a steamline break is not irnportant to the analysis ay M, N W WB5!iflgilDUSB A-9
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conclusions, and the minor differences between these events are addressed within subsection A.2.5 and Section A.9.
A.2.1 Medium Loss-of-Coolant Accident (MLOCA)
A medium loss-of-coolant accident is a break in the primary system that is large enough to depressurize the reactor coolant system to the point that the norrnal residual heat removal can be actuated without the opening of the automatic depressurization system lines. In other words, without automatic depressurization system, the reactor coolant system will depressurize below the 175 psia s!.atoff head of the normal residual heat removal pumps due to the
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blowdown from the break. The applicable event trees are:
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Medium loss-of-coolant accident I
Core makeup tank line break Direct vessel injection (DVI) line break De primary difference in these initiating events is the location of the break. He MLOCA event tree considers breaks on the hot leg or cold leg of the reactor coolant system that are equivalent or greater :han 5 in. inner diameter (see Section A.3).
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De core makeup tank line break is defined as any break in the core makeup tank balance line l
or core makeup tank injection line up to the check valves. De core makeup tank line break l
is very similar to a MLOCA on the cold leg, except the faulted core makeup tank is assumed j
I to be unavailable for core cooling. Therefore, the core makeup tank success criteria is one-out-of-one core makeup tanks for the core makeup tank line break, while it is one-out-of-two i
core makeup tanks on the MLOCA event tree. Normal residual heat removal is a possible I
source of long-term cooling, since the check valves in the core makeup tank line prevent the normal residual heat removal injection from being lost directly out the break.
De direct vessel injection line break has different effective break areas depending on the location of the break. For all locations, the effective break area initially corresponds to the 4.0 in. flow restrictor in the direct vessel injection line connection to the RPV. After the core I
makeup tank actuation signal, a second break pathway is created if the isolation valve opens for the core makeup tank connected to the broken direct vessel injection line. De second l
pathway can be equivalent to 3.7 in. ID or 8 in. ID depending on the location (refer to Figure A-1). He second pathway allows coolant loss from the reactor coolant system via the cold leg and core makeup tank. Furthermore, if the broken direct vessel injection line is the pathway for the normal residual heat removal, the normal residual heat removal injection flow is lost out the break. No success path is credited on the event tree for normal residual heat removal.
Each of the above event trees include automatic depressurization system success criteria:
ADM -- full depressurization, automatic actuation ADQ -- full depressurization, manual actuation May 31,1995 A-10 g
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A. MAAP4 Analyses to Srpport Success Criteria ne full depressurization cases rely on gravity drain from the in-containment refueling water storage tank for long-term cooling. Dere are no " partial" depressurization cases, since long-term cooling with the normal residual heat removal is possible without the opening of automatic depressurization system lines for this initiating event definition. Since automatic depressurization system is triggered from a core makeup tank level signal, the automatic actuation cases credit one core makeup tank and no accumulators. The manual actuation cases credit one accumulator and no core makeup tanks. Event tree paths with the failure of all core makeup tanks and accumulators result in core damage.
He MAAP4 analyses that support the initiating events discussed above consider the system response based on the different break scenarios. Results from the analyses are discussed in Section A.9.
The MLOCA cases are analyzed until the in-containment refueling water storage tank injects into the reactor coolant system and turns around the core temperature. His does not encompass the final top event on the event trees, which is recirculation. De success criteria for top event RECIR are addressed in subsection 6.4.25.
A.2.2 Intermediate Loss-of-Coolant Accident (NLOCA)
An intermediate loss-of-coolant accident (NLOCA) is a break in the primary system that is too small to allow normal residual heat removal injection without automatic depressurization system, but large enough to allow fourth-stage automatic depressurization system actuation without passive residual heat removal or stage one, two, or three automatic depressurization system lines. In other words, without automatic depressurization system, the reactor coolant system depressurizes below the stage four automatic depressurization system interlock of 1000 psia but remains above 175 psia due to the blowdown from the break. De applicable event tree is the intermediate loss-of-coolant accident.
In addition, there is a transfer to the NLOCA event tree from the transient event trees if a pressurizer safety valve fails to close after opening to relieve pressure during the transient.
The automatic depressurization system success criteria included in this initiating event are:
ADU -- partial depressurization, automatic actuation ADZ -- partial depressurization, manual actuation ADM -- full depressurization, automatic actuation ADQ -- full depressurization, manual actuation The partial depressurization cases rely on normal residual heat removal injection for long-term cooling. The full depressurization cases rely on either normal residual heat removal or gravity drain from the in-containment refueling water storage tank for long-term cooling, but the analyses are performed with the more limiting in-containment refueling water storage tank gravity drain case. Since automatic depressurization system is triggered from a core makeup tank level signal, the automatic actuation cases credit one core makeup tank and no accumulators. De manual actuation cases credit one accumulator and no core makeup tanks.
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A. MAAP4 Analyses to S:pport Srccess Criteria Event tree paths with the failure of all core makeup tanks and accumulators result in core damage.
He MAAP4 analyses that support the initiating events discussed above consider the system response for breaks in the primary system from 2 in. to 5 in. inner diameter (refer to Section A.3). In addition, the system response to a stuck open pressurizer safety valve is addressed. Results from the analyses are discussed in Section A.9.
De NLOCA cases are analyzed until the in-containment refueling water storage tank injects into the reactor coolant system and turns around the core temperature. This does not encompass the final top event on the event trees, which is recirculation. The success criteria for top event RECIR are addressed in subsection 6.4.25.
A.2.3 Small Loss-of Coolant Accident (SLOCA)
A small loss-of-coolant accident is a break in the primary system that is large enough that the CVS makeup flow is not sufficient to replace the lost inventory, yet the break is small enough that passive residual heat removal must operate or stage one, two, or three automatic depressurization system lines must open for the fourth-stage automatic depressurization system to be automatically actuated. In other words, without automatic depressurization system, the reactor coolant system pressure remains above 1000 psia, the stage four automatic depressurization system interlock. The applicable event trees are:
Small loss-of-coolant accident
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RCS leak
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passive residual heat removal heat exchanger tube rupture
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The reactor coolant system leak initiating event encompasses all breaks in the reactor coolant system up to 3/8 in., which is the largest size for which the CVS can compensate for the lost inventory. Although the reactor coolant system leak event addresses smaller breaks than the SLOCA event, the system response is similar if the CVS is not providing injection.
Therefore, if the CVS fails, or if the operator fails to take actions that will keep the CVS injecting, the reactor coolant system leak progresses as a SLOCA. Thus, the reactor coolant system leak initiating event is included in the St.OCA group for the MAAP4 analyses.
The passive residual heat removal heat exchanger tube rupture event fits within the break size of a SLOCA. The passive residual heat removal heat exchanger tube rupture is considered as a separate event tree, since it is feasible for the operator to terminate the event by isolating the break. In addition, the operation of the CVS could reduce the effective break size of the rupture. If the break is not isolated, the passive residual heat removal heat exchanger tube rupture progresses as a SLOCA. The MAAP4 analyses consider the success paths on the SLOCA event tree without CVS and without isolation of the break.
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A. MAAP4 Analyses 13 Srpport Success Criteria Each of the above event trees include automatic depressurization system success criteria:
ADI A -- partial depressurization, automatic, without passive residual heat removal ADV -- partial depressurization, automatic, with passive residual heat removal
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ADY - partial depressurization, manus), without passive residual heat removal ADZ - partial depressurization, manual, with passive residual heat removal ADA -- full depressurization, automatic, without passive residual heat removal ADS -- full depressurization, automatic, with passive residual heat removal ADC -- full depressurization, manual, without passive residual heat removal ADN -- full depressurization, manual, with passive residual heat removal i
Separate analyses are done to support each set of automatic depressurization system success I
criteria. In all cases, reactor trip is assumed to be successful. In the partial depressurization cases, only the normal residual heat removal is credited for long term heat removal. In the j
full depressurization cases, either normal residual heat removal or in-containment refueling water storage tank gravity drain lead to success paths, but the analyses are performed with the niore limiting in-containment refueling water storage tank gravity drain case. The automatic j
depressurization system actuation cases credit one core makeup tank and take no credit for accumulators. The manual automatic depressurization system actuation cases credit one accumulator and assume that the core makeup tanks have failed. Event tree paths with the failure of all core makeup tanks and accumulators result in core damage.
The MAAP4 analyses that support the initiating events discussed above consider the system response for breaks in the primary system up to 2 in. (refer to Section A.3). In addition, sensitivity analyses consider the effects of the passive residual heat removal tube rupture i
location. Results from the analyses are discussed in Section A.9.
The SLOCA cases are analyzed until either the normal residual heat removal injects or the m-1 containment refueling water storage tank gravity drains into the reactor coolant system and turns around the core temperature. This does not encompass the final top event on the event trees, which is recirculation. The success criteria for top event RECIR are addressed in subsection 6.4.25.
A.2.4 Steam Generator Tube Rupture lhe steam generator tube rupture initiating event is a specialized small loss-of-coolant accident. It is separated into its own category because the loss of primary coolant through the steam generator can result in different system response than when the loss of coolant is to the containment. There is a transfer to the steam generator tube rupture event tree if a tube rupture occurs as a consequence of a steamline break or stuck-open steam generator safety valve.
As discussed in Section 4.9, the steam generator tube rupture event can be described in terms of three phases. The first and second phases are scenarios where non-safety systems, operator actions, and autornatic isolation of the faulted steam generator are credited. These scenarios are not generally addressed with MAAP4 analyses. The third phase, when the actuation of
[ WestingilDilSB BL-A 13
DRAFT A. MAAP4 Analyses to Support Success Criteria 1
automatic depressurization system lines is needed to prevent core damage, is addressed with the MAAP4 cases.
De steam generator tube rupture event tree includes automatic depressurization system success criteria:
ADIA -- panial depressurization, automatic, without passive residual heat removal 4
ADV - partial depressurization, automatic, with passive residual heat removal ADY - partial depressurization, manual, without passive residual heat removal ADZ -- panial depressurization, manual, with passive residual heat removal ADA -- full depressurization, automatic, without passive residual heat removal ADS -- full depressurization, automatic, with passive residual heat removal e
ADC -- full depressurization, manual, without passive residual heat removal ADN -- full depressurization, manual, with passive residual heat removal Separate analyses are done to support each set of automatic depressurization system success criteria. In the partial depressurization cases, only the normal residual heat removal is credited for long term heat removal. In the full depressurization cases, either normal residual heat removal or in-containment refueling water storage tank gravity drain lead to success paths, but the analyses are performed with the more limiting in-containment refueling water storage tank gravity drain case. He automatic depressurization system actuation cases credit one core makeup tant, and take no credit for accumulators. He manual automatic depressurization system actaation cases credit one accumulator, and assume that the core makeup tanks have failed. Even: tree paths with the failure of all core makeup tanks and accumulators result in core damage.
For the MAAP4 analyses to support the automatic depressurization system success criteria above, there are a number of paths on the event tree to address. Generally, the analyses focus on scenarios without CVS or stanup feedwater, and with the steam generators isolated.
However, the effect of CVS and stanup feedwater, relative to the automatic depressurization system success criteria, are discussed in Section A.9.
He steam generator tube rupture cases are analyzed until either the normal residual heat removal injects or the in-containment refueling water storage tank gravity drains into the reactor coolant system and turns around the core temperature. His does not encompass the final top event on the event trees, which is recirculation. He success criteria for top event RECIR are addressed in subsection 6.4.25.
A.2.5 Transient Transients are initiating events in which there is no break in the reactor coolant system. The potential for core damage arises from the loss of heat remova! capabilities, resulting in the loss of primary side inventory through the pressurizer safety valves. The applicable event trees are:
Transient with main feedwater available Loss-of-feedwater flow to one steam generator
=
May 31,1995 A-14
DRAFT A. MAAP4 Analyses to Support Success Criteria Loss-of-feedwater flow to both steam generators Loss of condenser Loss of reactor coolant system flow Core power excursion Loss of component cooling / service water Loss of compressed air Loss-of-offsite power Main steam line break downstream of main steam isolation valves Main steam line break upstream of main steam isolation valves Main steam line safety valve stuck open For all the transient initiating events, there are success paths on the event trees when startup feedwater or passive residual heat removal is available. The verification of these paths is not addressed by the MAAP4 analyses (refer to Chapter 6). Instead, the MAAP4 analyses start from the common point in the above event trees, which includes: no main feedwater, no startup feedwater, no passive residual heat removal, no stuck open pressurizer safety valve, and successful reactor trip. With these conditions, the automatic depressurization system must be actuated to lower the reactor coolant system pressure to the point that either normal residual heat removal or in-containment refueling water storage tank gravity drain can provide long-term cooling for the core. The automatic depressurization system success criteria in most of the transient event trees are the same. In the loss-of-offsite power event tree, however, there are separate success criteria case names that represent the same scenarios, in terms of the MAAP4 analyses. The list below identifies the automatic depressurization system success criteria for most of the transient events, with the case names for the loss-of-offsite power event in parentheses:
ADI A -- partial depressurization, automatic (ADRA)
ADI -- partial depressurization, manual (ADR)
ADA -- full depressurization, automatic (ADAL, ADAB)
ADT -- full depressurization, manual (ADL, ADB)
Separate analyses are done to support each set of automatic depressurization system success criteria. In the pa:tial depressurization cases, only the normal residual heat removal is credited for long-term heat removal. In the full depressurization cases, either normal residual heat removal or in-containment refueling water storage tank gravity drain lead to success paths, but l
the analyses are performed with the more limiting in-containment refueling water storage tank gravity drain case. The automatic depressurization system actuation cases credit one core I
makeup tank, and take no credit for accumulators. The manual automatic depressurization system actuation cases credit one accumulator, and assume that the core makeup tanks have failed to inject.
For the MAAP4 analyses to support the above event trees, the reactor trip could be caused by a variety of signals, due to the different initiating events. Generally, a loss of feedwater is modeled, and the decrease in the steam generator water level is the reactor trip signal credited. 'Ihis is the limiting scenario, since the reactor stays at full power for approximately a minute, while the secondary heat sink starts to deplete. If there were a steamline break, the W wesunghouse F
=JL-A-15
==
DRAFT A. MAAP4 Analyses to Support Success CriterQJ secondary heat sink would also deplete quickly. An additional consideration is that events, such as core power excursion, will generate extra power that must be removed. For the loss-of-offsite power event, the reactor coolant pumps trip at the same time that the loss of feedwater occurs. Sensitivities on the effects of the reactor trip, the depletion of the secondary side heat sink, and the reactor power level are contained in Section A.9.
The transient cases are analyzed until either the normal residual heat removal injects or the in-containment refueling water storage tank gravity drains into the reactor coolant system and turns around the core temperature. This does not encompass the final top event on the event trees, which is recirculation. The success crit;ria for top event RECIR are addressed in subsection 6.4.25.
A.3 Break Size Definitions Loss-of-coolant accidents have been sub-divided into different categories for the initiating events, since the system response is dependent on the size of the break. The definition for each loss-of-coolant accident initiating event has been given in subsection A.2 and is based on whether different coolant injection sources can be used without automatic depressurization system actuation. The ability for coolant to be injected by a particular means, whether by pumps or gravity drain,is dependent on the reactor coolant system pressure. Table A-2 lists the reactor coolant system pressure " requirements" for each of the loss-of-coolant accident categories.
1 l
i May 31,1995 A 16 g
[ W85tlDghDUSB g=_
DRAFT A. MAAP4 Analyses to Support Success Criteria A.4 Baseline Cases Supporting Autornatic Depressurization System Success Criteria The majority of the MAAP4 analyses are focused on the verification of the automatic depressurization system success criteria. Table A-4 summarizes the automatic depressurization system success criteria definitions with applicable initiating events. The success criteria are grouped based on whether the reactor coolant system depressurization is partial or full, and whether the automatic depressurization system lines are automatically or manually opened.
Partial depressurization cases rely on the normal residual heat removal as the long-term inventory injection and heat removal source, while full depressurization cases rely on the in-containment refueling water storage tank g avity drain for this function. Normal residual heat removal can also be used in full depressurization cases, but the analyses focus on the in-containment refueling water storage tank gravity drain, since this is more difficult to achieve, and thus more limiting for automatic depressurization system success criteria definitions.
Table A-4 was constructed by reviewing the event trees to determine where each success criterion is used. For example, success criterion ADV is used in the SLOCA and steam generator tube rupture event trees. Success criterion ADV is used in success paths that credit any ore line from any stage automatic depressurization system, along with one core makeup tank, passive residual heat removal and normal residual heat removat Therefore, MAAP4 cases were analyzed for each of the initiating event categories with the system assumptions based on the event trees. Since the ADV success criterion includes the possibility of a line being opened from any stage, multiple cases were analyzed to cover each possibility. Stage two or stage three lines were considered to be one case, since they have the same line size; the only difference is an additional 2 minute delay from stage two to stage three. MLOCA, NLOCA success configurations do not include PRHR since the PRHR system is not credited on the event tree for these LOCA initiating events. Transient initiating events do not include PRHR since operation of the PRHR results in success without depressurization for the non-LOCA initiating events. For each success criterion, the baseline MAAP4 case and some supporting cases are listed on Table A-4, and are discussed in the sections below. Results from all the MAAP4 cases are summarized in Section A.9.
The following sections summarize the results from the MAAP4 cases identified in Table A-4.
Subsection A.4.1 addresses automatic depressurization system actuation cases, with one core makeup tank, no accumulators and including normal residual heat removal. Subsection A.4.2 addresses manual automatic depressurization system actuation cases with no core makeup tanks, with one accumulator and with normal residual heat removal. Subsection A.4.3 addresses automatic depressurization system actuation cases with one core makeup tank, no accumulators and including in-containment refueling water storage tank grasity drain.
Subsection A.4.4 addresses manual automatic depressurization system actuation cases with no core makeup tanks, with one accumulator and with in-containment refueling water storage tank gravity drain. In each section, cases with and without passive residual heat removal are considered as defined in the event trees. In the manual actuation cases, different operator action times are considered.
[ W85tinghDlJS8 h
A-17
DRAFT A. MAAP4 Analyses to Scpport Success Criteria i
Possible interactions from other systems have been considered, and are addressed in j
subsection A.8.1.
A.4.1 Automatic Partial Depressurization for RNS Operation Initiating events addressed by the MAAP4 analyses, except MLOCA (which includes CMT and SI line breaks), include pathways on the event trees that rely on " partial" depressurization by the automatic depressurization system to reduce the reactor coolant system pressure below the normal residual heat removal shutoff head. MLOCA cases do not require the automatic depressurization system for normal residual heat removal operadon, since the MLOCA break size has been defined based on allowing normal residual heat removal operation without the opening of any automatic depressurization system lines.
Automatic actuation of the depressurization system is based on a low core makeup tank level signal. Therefore the automatic depressurization system valves can be automatically opened only if at least one core makeup tank injects. Failure of the core makeup tank to inject, which requires operator action to open the automatic depressurization system valves, is addressed in subsection A.4.2.
This section documents the MAAP4 analyses that define the number of automatic depressurization system valves that must automatically open for success criteria ADIA, ADRA, ADU and ADV. The ADIA, ADRA and ADU success criteria represent cases without the passive residual heat removal, while the ADV success criterion represents cases with the passive residual heat removal. The goal of these analyses is to verify the minimum number of automatic depressurization system valves from any stage that will be sufficient to achieve success.
A.4.1.1 NLOCA Success Criterion ADU ADU is the success criterion for automatic partial depressurization for the intermediate LOCA initiating event. Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and long-term injection is supplied by at least one normal RHR pump. The success configuration for success criterion ADU is at least:
2 of 2 stage 1 or 1 of 8 stage 2,3,4 ADS lines.
=
The assumptions for the baseline case (MAAP4 case xib) are:
minimum ADS:
2 stage I lines minimum short term injection:
1CMT minimum long term injection:
1 RNS pump limiting break size and location:
2" diameter cold leg break.
=
The MAAP4 results for the baseline and supporting cases for success criterion ADU are presented in Tables A-4.la and A-4.lb. Baseline case xib results in a peak core temperature of 1147'F. 'D1is case demonstrates substantial margin to the 2200*F acceptance criterion and E
W WesdnghDljSB A-18
- a==
==
DRAFT A. MAAP4 Analyses to Srpport Success Criteria to the temperatures at which substantial oxidation is expected to occur. Additional supporting cases are presented ir. Tables A-4.la and A-4.lb which demonstrate that the 2" diameter cold leg break is the ligniting case for success criterion ADU, and that the ADS success configuration of 2 st tge one lines is more limiting than one stage 2,3 or one stage 4 lines.
A.4.1.2 SLOCA Success Criterion ADIA ADI A is the success criterion for automatic partial depressurization for the small LOCA initiating event with PRHR failure. Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and lorg-term injection is supplied by at least one normal RHR pump. Since the SLOCA initiating event results in elevated RCS pressures, the stage 4 volves are interlocked out and cannot open without the successful operation of stages 1,2 or 3. The success configuration for success criterion ADI A is at least:
2 of 2 stage 1 or 1 of 4 stag: 2,3 ADS lines.
The assumptions for the baseline case (MAAP4 case sl6k) are:
minimum ADS:
2 stage I lines minimum short term injection:
1CMT minimum long term injection:
1 RNS pump limiting break size and location:
0.5" diameter hot leg break.
The MAAP4 results for the baseline and supporting cases for success criterion ADIA are presented in Tables A-4.2a and A-4.2b. Baseline case sl6k results in a pea': core temperature of 1284*F. This case demonstrates substantial margin to the 2200*F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. Additional supporting t.ases are presented in Tables A-4.2a and A-4.2b which demonstrate that the 0.5 inch diameter hot leg break is the limiting case for success criterion ADIA, and that the ADS success configuration of two stage I lines is more limiting than one stage 2,3 line.
A.4.1.3 SLOCA Success Criterion ADV ADV is the success criterion for automatic partial depressurization for the small LOCA initiating event with PRHR success. Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and long-term injection and heat removal are supplied by at least one normal RHR pump and the PRHR.
Since the PRHR reduces the RCS pressure below the stage 4 valve interlock prescure, stage 4 can open without the successful operation of stages 1,2 or 3. The success configuradan for success criterion ADV is at least:
1 of 10 stage 1,2,3,4 ADS lines.
[ WE5tinghDijSe h
A 19
DRAFT A. MAAP4 Analyses to Scpport Success Criteria The assumptions for the baseline case (MAAP4 case s10) are:
minimum ADS:
I stage I line minimum short term injection:
1CMT minimum long term injection:
1 RNS pump successful PRHR operation limiting break size and location:
0.5" diameter cold leg break.
The MAAP4 results for the baseline and supporting cases for success criterion ADV are presented in Tables A-4.3a and A-4.3b. Baseline case s10 results in no core uncovery. This case demonstrates substantial margin to the 2200'F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. Additional supporting cases are presented in Tables A-4.3a and A-4.3b. None of the cases result in core uncovery. The single stage one valve provides the least depressurization capacity, and is considered to be the limiting case.
A.4.1.4 SGTR Success Criterion ADIA ADI A is the success criterion for automatic partial depressurization for the SGTR initiating event with PRHR failure. Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and long-term injection is supplied by at least one normal RHR pump. Since the SGTR initiating event results in elevated RCS pressures, the stage 4 valves are interlocked out and cannot open without the successful operation of stages 1,2 or 3. The success configuration for success criterion ADIA is at least:
2 of 2 stage 1 or 1 of 4 stage 2,3 ADS lines.
The assumptions for the baseline case (MAAP4 case g10a) are:
minimum ADS:
2 stage 1 lines minimum short term injection: 1CMT e
minimum long term injection: 1 RNS pump break:
SGTR The MAAP4 results for the baseline and supporting case for success criterion ADIA are presented in Tables A-4.4a and A-4.4b. Baseline case g10a results in a peak core temperature of 1109'F. This case demonstrates substantial margin to the 2200'F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. Additional supporting cases are presented in Tables A-4.4a and A-4.4b which demonstrate that the ADS success configuration of 2 stage one lines is more limiting than one stage 2,3 line.
May 31,1995 g
9
.N A-20 EtEL %
=
DRAFT rm A. MAAP4 Analyses to S:pport Success Criteria f
1 A.4.1.5 SGTR Success Criterion ADV ADV is the success criterion for automatic partial depressurization for the SGTR initiating event with PRHR success. Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and long-term injection and heat removal are supplied by at least one normal RHR pump and the PRHR. De secondary side is not isolated, otherwise the depressurization of the PRHR reduces the pressura., below the secondary relief valve setpoint and the loss of coolant is terminated and the sequence results in success. Since the PRHR reduces the RCS pressure below the stage 4 valve interlock pressure, stage 4 can open without the successful operation of stages 1,2 or 3. De success configuration for success criterion ADV is at least.
1 of 10 stage 1,2,3,4 ADS lines.
The assumptions for the baseline case (MAAP4 case gil) are:
minimum ADS:
1 stage 1 line minimum short term injection: 1CMT e
minimum long term injection: 1 RNS pump successful PRHR operation break:
unisolated SGTR Re MAAP4 results for the baseline and supporting cases for success criterion ADV are presented in Tables A-4.5a and A-4.5b. Baseline case gli results in no core uncovery. His case demonstrates substantial margin to the 2200*F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. Additional supporting cases are presented in Tables A-4.Sa and A-4.5b. None of the cases result in core uncovery. The single stage one valve provides the least depressurization capacity, and is considered to be the limiting case.
A.4.1.6 Transient Success Criteria ADIA and ADRA ADIA is the cucc-ss criterion for automatic partial depressurization for the non-LOCA initiating events. ADRA is the equivalent of ADIA for loss of offsite power events.
Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and long-term injection is supplied by at least one normal RHR pump. Since the transient initiating events result in elevated RCS pressures, the stage 4 valves are interlocked out and cannot open without the successful operation of stages 1,2 or 3. The success configuration for success criteria ADI A and ADRA is at least:
2 of 2 stage 1 or 1 of 4 stage 2,3 ADS lines.
[ WestinghDUse A-21
DRAFT A. MSAP4 Analyses to Support Success Criteria The assumptions for the baseline case (MAAFi case 11) are:
minimum ADS:
2 stage one lines minimum short term injection: ICMT e
minimum long term injection: 1 RNS pump limiting initiating event:
loss of main and startup feedwater (see section A.9.5).
The MAAP4 results for the baseline and supponing cases for success criterion ADIA are presented in Tables A-4.6a and A-4.6b. Baseline case 11 results in a peak core temperature of 1305'F. His case demonstrates substantial margin to the 2200'F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. An additional supporting case is presented in Tables A-4.6a and A-4.6b which demonstrate that the ADS success configuration of 2 stage one lines is more limiting than one stage 2,3 line.
A.4.2 Manual Depressurization for RNS Operation The automatic depressurization system can only be automatically actuated based on a low core makeup tank level signal. If both core makeup tanks fail to inject water, then it is necessary for the operator to manually open the automatic depressurization system lines. This is the scenario addressed in this section, which covers success criteria AD1, ADUM, ADR and ADZ. All of the initiating events being addressed by MAAP4 analyses, except MLOCA, use one of these success criteria. By definition, the MLOCA initiating event can depressurize the reactor coolant system sufficiently without ADS to allow normal residual heat removal injection.
When manual automatic depressurization system actuation is credited, the operator action time is an uncertainty that must be considered. De operator action time needs to be defined from a signal that failed to perform its function. For transients, the focus of the 5 Mor is on heat removal. If both startup feedwater and the passive residual heat removal fail to n.ahte, the operator would have the necessary indications that manual action may be needed. This indication will generally occur for transient initiating events when a low steam generator water level signal fails to acmate the passive residual heat removal. For loss-of-coolant accidents, the focus of the operator is on inventory control. The indication that manual actuation may be needed is when the core makeup tanks fail to inject after a low pressurizer pressure or low pressurizer level signal. The core makeup tank actuation signal also produces a passive residual heat removal actuation signal. Berefore, operator action time for manual automatic depressurization system actuation could always be referenced from the time of the passive residual heat removal actuation signal for all the initiating events. For loss-of-coolant accidents, this is the same as if the operator action time is referenced from the core makeup tank actuation signal.
De human reliability analysis for this action does not credit delay times greater than 30 minutes. Therefore, the baseline sequences only consider the operator action delays for 30
" "# 3 ' ' ' *
- E W westinghouse A-22
- - * = =
l l
DRAFT r
A. MAAP4 Analyses to Srpport Success Criteria j
j
! dJ d
b minutes or less. Cases with longer delay times are included with all the MAAP4 supporting analyses in section 4.9. De core makeup tank actuation signal is used as a starting point to measure the operator action time, but the core makeup tank fails to inject. Only accumulator j
injection is modeled prior to normal residual heat removal injection.
A.4.2.1 NLOCA Success Criterion ADUM ADUM is the success criterion for manual panial depressurization for the intermediate LOCA initit. ting event. De need for manual actuation of the depressurization system on the event tree path using ADUM is a result of the failure of both the core makeup tanks which generate the ADS signal, so shon term makeup water is supplied by an accumulator. Long-term t
injection is supplied by at least one normal RHR pump. De success configuration for success criterion ADUM is at least:
2 of 2 stage 1 or 1 of 8 stage 2,3,4 ADS lines maximum operator action delay of 30 minutes after the CMT signal he assumptions for the baseline case (MAAP4 case xh2) are:
minimum ADS:
2 stage 1 lines minimum short term injection:
I accumulator e
minimum long term injection:
1 RNS pump l
operator delay time:
15 minutes after CMT signal i
limiting break size and location:
2" diameter cold leg break.
He MAAP4 results for the baseline and supporting cases for success criterion ADUM are presented in Tables A-4.7a and A-4.7b. Baseline case x2h results in a peak core temperature of 1127'F. His case demonstrates substantial margin to the 2200 F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. Additional supporting cases are presented in Tables A-4.7a and A-4.7b which demonstrate that the 2" diameter break is the limiting case for success criterion ADUM with little sensitivity to the break location.
The ADS success configuration of 2 stage one lines is more limiting than one stage 2/3 or one stage 4 lines. De operator action delay time of 15 minutes produces a higher peak temperature than the 30 minute delay since the & cay heat is higher at the earlier time and the core uncovery occurs as a result of the depressurization.
A.4.2.2 SLOCA Success Criterion ADI ADI is the success criterion for manual panial depressurization for the small LOCA initiating event with PRHR failure. The need for manual actuation of the depressurization system on the event tree path using ADI is a result of the failure of both the core makeup tanks which generate the ADS signal, so short term makeup water is supplied by an accumulator. Long-term injection is supplied by at least one normal RHR pump. De small LOCA initiating
[ WestiflghDUS8 l
A-23
~
DRAFT y,,,, in,1,,,, to srg,o,, succes, criteri-event results in an elevated RCS pressure above the interlock pressure of the stage 4 ADS valves, however, the interlock can be manually overridden to open stage 4. The success configuration for success criterion ADI is at least:
2 of 2 stage 1 or 1 of 8 stage 2,3,4 ADS lines maximum operator action delay of 30 minutes after the CMT signal The assumptions for the baseline case (MA/.P4 case s19b2) are:
minimum ADS:
2 stage 1 lines minimum short term injection:
I accumulator minimum long term injection:
1 RNS pump operator delay time:
15 minutes after CMT signal limiting break size and location:
0.5" di? meter hot leg break.
The MAAP4 results for the baseline and supporting :ases for success criterion ADI are presented in Tables A-4.8a and A-4.8b.
Baseline case s19b2 results in a peak core temperature of 1266*F. This case demonstrates suNtantial margin to the 2200*F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur.
Additional supporting cases are presented in Tables A-4.8a and A-4.8b which demonstrate that the 0.5" diameter break is the limiting case for success criterion ADI with little sensitivity to the break location. The ADS success configuration of 2 stage one lines is more limiting than one stage 2/3 or one stage 4 lines. The operator action delay time of 15 minutes produces a higher peak temperature than the 30 minute delay since the decay heat is higher at the earlier time and the core uncovery occurs as a result of the depressurization.
A.4.2.3 SLOCA Success Criterion ADZ ADZ is the success criterion for manual partial depressurization for the small LOCA initiating event with PRHR success. The need for manual actuation of the depressurization system on the event tree path using ADZ is a result of the failure of both the core makeup tanks which generate the ADS signal, so short term makeup water is supplied by an accumulator. Long-term injection is supplied by at least one normal RIIR pump. The small LOCA initiating event results in an elevated RCS pressure above the interlock pressure of the stage 4 ADS valves, however, the interlock can be manually overridden to open stage 4. The success configuration for success criterion ADZ is at least:
1 of 10 stage 1,2,3,4 ADS lines maximum operator action delay of 30 minutes after the CMT signal The assumptions for the baseline case (MAAP4 case sl3a) are:
minimum ADS:
1 stage 1 lines M"7 31' "
M.-i===
W westinghouse A-24 m
=
i
)
DRAFT A. MAAP4 Analyses to Support Success Criteria minimum short term injection:
I accumulator minimum long term injection:
1 RNS pump l
successful PRHR operation
=
operator delay time:
15 minutes after CMT signal
=
limiting break size and location:
0.5" diameter cold leg break.
i
=
1 he MAAP4 results for the baseline and supporting cases for success criterion ADZ are l
presented in Tables A-4.9a and A-4.9b Baseline case s13a results in no core uncovery. His l
case demonstrates substential margin to the 2200*F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. Additional supporting cases are presented in Tables A-4.9a and A-4.9b which demonstrate that none of the cases result in core uncovery. The ADS success configuration of I stage one line is assumed to be more limiting than one stage 2/3 or one stage 4 lines since it is the smallest line. De operator action delay time of 15 minutes is assumed to be the most limiting since it results in an earlier core uncovery and higher decay heat.
A.4.2.4 SGTR Success Criterion ADI ADI is the success criterion for manual partial depressurization for the SGTR initiating event with PRHR failure. The need for manual actuation of the depressurization system on the event tree path using ADI is a result of the failure of both the core makeup tanks which generate the ADS signal, so short term makeup water is supplied by an accumulator. Long-term injection is supplied by at least one normal RHR pump. De SGTR initiating event results in an elevated RCS pressure above the interlock pressure of the stage 4 ADS valves, however, the interlock can be manually overridden to open stage 4. The success configuration for succm criterion AD1 is at least:
2 of 2 stage 1 or 1 of 8 stage 2,3,4 ADS lines
=
maximum operator action delay of 30 minutes after the CMT signal The assumptions for the baseline case (MAAP4 case g12d) are:
minimum ADS:
2 stage 1 lines minimum short term injection: 1 accumulator e
minimum long term injection: 1 RNS pump operator delay time:
15 minutes after CMT signal l
break:
SGTR l
a De MAAP4 results for the baseline and supporting cases for success criterion ADI are presented in Tables A-4.10a and A-4.10b.
Baseline case g12d results in a peak core W W85tinEhDilSB o
..a.--
A-25
DRAFT y ma m
iii A. MAAP4 Analyses to Srpport Success Criteria temperature of 1034*F. This case demonstrates substantial margin to the 2200*F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur.
Additional supponing cases are presented in Tables A-4.10a and A-4.10b which demonstrate that the ADS success configuration of 2 stage one lines is the most limiting. De operator action delay time of 15 minutes produces a higher peak temperature than the 30 minute delay since the decay heat is higher at the earlier time and the core uncovery occurs as a result of the depressurization.
A.4.2.5 SGTR Success Criterion ADZ ADZ is the success criterion for manual partial depressurization for the SGTR initiating event with PRHR success. The need for manual actuation of the depressurization system on the event tree path using ADZ is a result of the failure of both the core makeup tanks which generate the ADS signal, so short term makeup water is supplied by an accumulator. Long-term injection is supplied by at least one normal RHR pump. The secondary side is not isolated, otherwise the depressurization of the PRHR reduces the pressure below the secondary relief valve setpoint and the loss of coolant is terminated and the sequence results in success.
The SGTR initiating event results in an elevated RCS pressure above the interlock pressure of the stage 4 ADS valves, however, the interlock can be manually overridden to open stage
- 4. The success configuration for success criterion ADZ is at least:
1 of 10 stage 1,2,3,4 ADS lines a
maximum operator action delay of 30 minutes after the CMT signal The assumptions for the baseline case (MAAP4 case gl3) are:
minimum ADS:
1 stage 1 lines minimum shon term injection: I accumulator e
minimum long term injection: 1 RNS pump operator delay time:
15 minutes after CMT signal break:
unisolated SGTR Re MAAP4 results for the baseline and supporting cases for success criterion ADZ are presented in Tables A-4.lla and A-4.llb. Baseline case gl3 results in no core uncovery.
'lhis case demonstrates substantial margin to the 2200*F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. Additional supporting cases are presented in Tables A-4.9a and A-4.9b which demonstrate that none of the cases result in core uncovery. The ADS success contiguration of I stage one line is assumed to be more limiting than one stage 2/3 or one stage 4 lines since it is the smallest line. De operator action delay time of 15 minutes is assumed to be the most limiting since will result in an earlier core uncovery.
""Y 3 ' ' "
M W westinghouse A-26
==
I DRAFT A. MAAP4 Analyses to Srpport Success Criteria A.4.2.6 Transient Success Criteria AD1 and ADR AD1 is the success criterion for manual panial depressurization for the transient initiating events. ADR is the equivalent success criteria as AD1 for loss of offsite power. The need for manual actuation of the depressurization system on the event tree path using ADI is a result of the failure of both the core makeup tanks which generate the ADS signal, so short term makeup water is supplied by an accumulator. Long-term injection is supplied by at least one normal RHR pump. The transient initiating events result in an elevated RCS pressure above the interlock pressure of the stage 4 ADS valves, however, the interlock can be manually overridden to open stage 4. The success configuration for success criterion ADI and ADR is at least:
2 of 2 stage 1 or 1 of 8 stage 2,3,4 ADS lines maximum operator action delay of 30 minutes after the PRHR signal The assumptions for the baseline case (MAAP4 case t3h) are:
minimum ADS:
2 stage 1 lines minimum short term injection: 1 accumulator minimum long term injection: 1 RNS pump operator delay time:
15 minutes after PRHR signal limiting initiating event:
loss of main and startup feedwater (see section A.9.5).
The MAAP4 results for the baseline and supponing cases for success criterion ADI are presented in Tables A-4.12a and A-4.12b.
Baseline case 13h results in a peak core temperature of 1280'F. This case demonstrates substantial margin to the 2200 F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur.
Additional supporting cases are presented in Tables A-4.12a and A-4.12b which demonstrate that the ADS success configuration of 2 stage one lines is more limiting than one stage 2,3 or one stage 4 lines. The operator action delay time of 15 minutes produces a higher peak temperature than the 30 minute delay since the decay heat is higher at the earlier time and the core uncovery occurs as a result of the depressurization.
A.4.3 Automatic Depressurization for IRWST Gravity Drain Initiating events addressed by the MAAP4 analyses include " full" depressurization pathways on the event trees that reduce the reactor coolant system pressure so that in-containment refueling water storage tank gravity drain can occur. Automatic actuation of the automatic depressurization system is based on a low core makeup tank level signal. Therefore the automatic depressurization system valves can be automatically opened only if at least one core makeup tank injects. Failure of the core makeup tank to inject, requiring manual action to open the automatic depressurization system lines,is addressed in subsection A.4.4.
May 31,1995 3 WB5tinghDtlSe b=
A-27
A. MAAP4 Analyses to Support Success Criteria This section documents the MAAP4 analyses that define the number of automatic depressurization system lines that must automatically open for success criteria ADAB, ADAL, ADA, ADS and ADM. The ADAB, ADAL, ADA and ADM success criteria represent cc.ses without the passive residual heat removal, while case ADS includes passive residual hat removal. The goal of these analyses is to identify the rainimum number of ADS lines that must open to allow gravity injectiori and achieve success.
A.4.3.1 MLOCA Success Criterion ADM ADM is the success criterion for automatic full depressurization for the medium LOCA initiating event. Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and long-term injection is supplied by at least one line of gravity injection. The success configuration for success criterion ADM is at least:
2 of 4 stage 4 ADS lines.
The assumptions for the baseline case (MAAP4 case m3g4) are:
minimum ADS:
2 stage 4 lines
=
containment isolation failure
=
minimum short term injection:
1CMT e
minimum long term injection:
I gravity injection line limiting break size and location:
5" diameter cold leg break.
=
The MAAP4 results for the baseline and supporting cases for success criterion ADM are presented in Tables A-4.13a and A-4.13b. Baseline case m3g4 results in no core uncovery.
This case demonstrates substantial margin to the 2200 F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. Additional supporting cases with variations in break size and location are presented in Tables A-4.13a and A-4.13b which also result in no core uncovery.
A.4.3.2 NLOCA Success Criterion ADM ADM is the success criterion for automatic full depressurization for the intermediate LOCA initiating event. Automatic actuation of the depressurization system requbes at least one core makeup tank to generate the signal on low level, and long-term injection is supplied by at least one gravity injection line. The success configuration for success criterion ADM is at least:
2 of 4 stage 4 ADS lines.
=
N W W85tlDghDi]Se A-28 h
==
N A. MAAP4 Analyses to S:pport Success Criteria ne assumptions for the baseline case (MAAP4 case x3d4) are:
minimum ADS:
2 stage 4 lines containment isolation failure e
minimum short term injection:
1 Chff e
minimum long term injection:
1 gravity injection line limiting break size and location:
2" diameter hot leg break.
The MAAP4 results for the baseline and supponing cases for success criterion ADM are presented in Tables A-4.14a and A-4.14b. Baseline case x3d4 results in a peak core temperature of 956*F. This case demonstrates substantial margin to the 2200*F acceptance cdterion and to the temperatures at which sihstantial oxidation is expected to occur.
Additional supporting cases are presented in Tables A-4.14a and A-4.14b winch demonstrate t' tat the 2" diameter hot leg break is the limitin}, case for success critedon ADM.
AA.3.3 SLOCA Success Criterion ADA ADA is the success criterion for automhtic fu'l &p~ce'rization for the small LOCA initiating event with PRHR failure. Automatic actuafra M & dyressurization system requires at least one core makeup tank to generate the signal un iow avel, and long-term injection is supplied by at least one gravity injection line. Since the SLOCA initiating event results in elevated RCS pressures, the stage 4 valves are interlocked out and cannot open without the successful operation of stages 1,2 or 3. The success configuration for success criterion ADA is at least:
3 of 4 stage 2,3 ADS lines, or
=
1 of 4 stage 2,3 and 1 of 4 stage 4 ADS lines.
He assumptions for the baseline case (MAAP4 case sit 2) are:
minimum ADS:
3 stage 2,3 lines containment isolation failure
=
minimum short term injection:
1CMT
=
minimum long term injection:
I gravity injection line limiting break size and location:
1.75" diameter cold leg break.
e He MAAP4 results for the baseline and supporting cases for success criterion ADA are presented in Tables A-4.15a and A-4.15b.
Baseline case sit 2 results in a peak core temperature of 1534*F. 'Ilds case demonstrates substantial margin to the 2200*F acceptance criterion, but sensitivity cases with minimum gravity injection flow and minimum CMT flow are performed to assure that rapid cladding oxidation does not occur and drive the temperature
[ Westingt10USB SlL-A-29
DRAFT A. MAAP4 Analyses to Support Success Criteria hayond the limit. Reasonable limits on the short-term and Icrf term injection flows do not reself in significant peak temperature differences. Additional supporting cases are presented in Tatdes A-4.15a and A-4.15b which demonstrate that the 1.75 inch diameter cold leg break is the limiting case for success criterion ADA, and that the ADS success configuration of 3 stage 2.3 lines is more limiting than one stage 2,3 and one stage 4 lines.
/. 4.3.4 SLOCA Success Criterion ADS ADS is the success criterion for automatic full depressurization for the small LOCA initiating event with PRHR success. Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and long-term injection and heat removal are supplied by at least one gravity injection line and the PRHR. Since the PRHR reduces the RCS pressure below the stage 4 valve interlock pressure, stage 4 can open without the successful operation of stages 1,2 or 3. The success configuration for success criterion ADS is at least:
3 of 4 stage 2,3 ADS lines or
=
1 of 4 stage 4 ADS lines.
The assumptions for the baseline case (MAAP4 case s4z) are:
minimum ADS:
3 stage 2,3 lines
=
containment isolation failure
=
minimum short term injection:
1CMT
=
minimum long term injection:
I gravity injection line successful PRHR operation
=
limiting break size and location:
1.75" diameter hot leg break.
=
The MAAP4 results for the baseline and supporting cases for success criterion ADS are presented in Tables A-4.16a and A-4.16b.
Baseline case s4r results in a peak core temperature of 1251*F. This case demonstrates substantial margin to the 2200'F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur.
Additional supporting cases are presented in Tables A-4.16a and A-4.16b. The analyses show that the 1.75 inch diameter break is the limiting break size.
The analyses show little sensitivity to break location. The 3 stage 2,3 ADS line configuration is more limiting than the I stage 4 line.
An interesting result of these analyses is that the smallest of the SLOCA break sizes with operational PRHR has lower peak temperatures with no containment isolation. This occurs because the PRHR is able to remove more heat at the lower pressures and temperatures in the containment, and the heat removal compensates for the difficulty in gravity injection at the WeStinghDUSB A 30
DRAFT
==
A. MAAP4 Analyses to S;pport Success Criteria lower pressures. The same effect is not seen at the larger end of the break range since the PRHR is not as e1Tective at the lower pressures in th: RCS.
A.4.3.5 SGTR Success Criterion ADAG ADAG is the success criterion for automatic full depressurization for the SGTR initiating event with PRHR failure. Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and long-term injection is supplied by at least one gravity injection line. Since the SGTR initiating event results in elevated RCS pressures, the stage 4 valves are interlocked out and cannot open without the successful operation of stages 1,2 or 3. The success configuration for success criterion ADAG is at least:
1 of 4 stage 2,3 and 1 of 4 stage 4 ADS lines.
The assumptions for the baseline case (MAAP4 case gl4e) are:
minimum ADS:
I su.ge 3 at:11 stage 4 line containment isolation failure minimum short term injection: 1CMT
=
minimum long term injection: I gravity injection line break:
SGTR e
i The MAAP4 results for the baseline case for success criterion ADAG is presented in Tables A-4.17a and A-4.17b. Baseline case gl4e results in a peak core temperature of 685'F. This case demonstrates substantial margin to the 2200*F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur.
A.4.3.6 SGTR Success Criterion ADS ADS is the success criterion for automatic full depressurization for the SGTR initiating event with PRHR success. Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and long-term injection and heat removal are supplied by at least one gravity injection line and the PRHR. The secondary side is not isolated, otherwise the depressurization of the PRHR reduces the pressure below the secondary relief valve setpoint and the loss of coolant is terminated and the sequence results in success. Since the PRHR reduces the RCS pressure below the stage 4 valve interlock pressure, stage 4 can open without the successful operation of stages 1,2 or 3. The success configuration for success criterion ADS is at leasu 3 of 4 stage 2,3 ADS lines or i
1 of 4 stage 4 ADS lines.
[ WestinghDUse 6-A-31
DRAFT A. MAAP4 Analyses to S;pport Success Criteria The assumptions for the baseline case (MAAP4 case gl5) are:
minimum ADS:
3 stage 2,3 lines containment isolation failure e
minimum short term injection: 1CMT e
minimum long term injection: 1 gravity injxtion line successful PRHR operation e
break:
unisolated SGTR.
The MAAP4 results for the baseline and supporting cases for success criterion ADS are presented in Tables A-4.18a and A-4.18b. Baseline case s4z results in no core uncovery.
This case demonstrates substantial margin to the 2200*F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. Additional supponing cases are presented in Tables A-4.18a and A-4.18b, and none result in core uncovery.
A.4.3.7 Transient Success Criteria ADA, ADAL, ADAll ADA is the success criterion for automatic full depressurization for the non-LOCA initiating events. ADAL and ADAB are the equivalent success criteria for loss of offsite power and station blackout, respectively. Automatic actuation of the depressurization system requires at least one core makeup tank to generate the signal on low level, and long-term injection is supplied by at least one gravity injection line. Since the transient initiating events result in elevated RCS pressures, the stage 4 valves are interlocked out and cannot open without the successful operation of stages 1,2 or 3. 'Ihe success configuration for success criteria ADA, ADAL and ADAB is at least:
3 of 4 stage 2,3 ADS lines, or 1 of 6 stage 1,2,3 and 1 of 4 stage 4 ADS lines.
j
'the assumptions for the baseline case (MAAP4 case 15t) are:
minimum ADS:
3 stage 2,3 lines containment isolation failure
=
l minimum shon term injection: 1CMT minimum long term injection: I gravity injection line lir iting initiating event:
loss of main and startup feedwater (see section A.9.5).
May 31,1995 g
g A-32 latil=L-
DRAFT A. MAAP4 Analyses to S:pport Success Criteria The MAAP4 results for the baseline and supporting cases for success criterion ADA are presented in Tables A-4.19a and A-4.19b. Baseline case 15t results in a peak core temperature of 1262'F. This case demonstrates substantial margin to the 2200*F acceptance criterion and to the temperatures at which substantial oxidation is expected to occur. Additional supporting cases are presented in Tables A-4.19a and A-4.19b which demonstrate that the ADS success configuration of 3 stage 2,3 lines is more limiting than one stage 1 and one stage 4 lines.
A.4.4 Manual Depressurization for IRWST Gravity Drain The automatic depressurization system can only be automatically actuated based on a low core makeup tank level signal. If both core makeup tanks fail to inject water, then it is necessary for the operator to manually open the automatic depressurization system lines. This is the scenario addressed in this section, which covers success criteria for ADB, ADL, ADT, and ADQ. The MLOCA, NLOCA, SLOCA, SGTR and transient initiating events use these success criteria.
When manual automatic depressurization system actuation is credited, the operator action time is an uncertainty that must be considered. The operator action time needs to be defined from a signal that failed to perform,ts function. For transients, the focus of the operator is on heat removal. If both startup feedwater and the passive residual heat removal fail to initiate, the operator would have the necessary indications that manual action may be needed. This indication will generally occur for transient initiating events when a low steam generator water level signal fails to actuate the passive residual heat removal. For loss-of-coolant accidents, the focus of the operator is on inventory control. The indication that manual actuation may be needed is when the core makeup tanks fail to inject after a low pressurizer pressure or low pressurizer level signal. The core makeup tank actuation signal also produces a passive residual heat removal actuation signal. Therefore, operator action time for manual automatic depressurization system actuation could always be referenced from the time of the passive residual heat removal actuation signal for all the initiating events. For loss-of-coolant accidents, this is the same as if the operator action time is referenced from the core makeup tank actuation signal.
The event tree quantification does not credit delay times greater than 30 minutes. Therefore, the baseline sequences only consider the operator action delays for 30 minutes or less. Cases with longer delay times are included with all the MAAP4 supporting analyses in section 4.9.
The core makeup tank actuation signal is used as a starting point to measure the operator action time, but the core makeup tank fails to inject. Only accumulator injection is modeled prior to normal residual heat removal injection.
A.4.4.1 MLOCA Success Criterion ADQ ADQ is the success criterion for manual full depressurization for the medium LOCA initiating event. The need for manual actuation of the depressurization system on the event tree path using ADQ is a result of the failure of both the core makeup tanks which generate the ADS signal, so short term makeup water is supplied by an accumulator. Long-term injection is
[ WestinghDuse tie b -
A-33
A. MAAP4 Analyses to SIPPort Success Criteria l
l supplied by at least one gravity injection line. The success configuration for success criterion ADQ is at least:
2 of 4 stage 4 ADS lines maximum operator action delay of 30 minutes after the CMT signal The assumptions for the baseline case (MAAP4 case m6e5) are:
minimum ADS:
2 stage 4 lines containment isolation failure
=
minimum short term injection:
I accumulator e
minimum long term injection:
I gravity injection line operator delay time:
30 minutes after CMT signal limiting break size and location:
8.75" diameter hot leg break.
He MAAP4 results for the baseline and supporting cases for success criterion ADQ are presented in Tables A-4.20a and A-4.20b. Baseline case m6e5 results in a peak core t mperature of 1554'F. This case demonstrates substantial margin to the 2200*F acceptance criterion, but sensitivity cases with minimum gravity injection flow and minimum accumulator flow are performed to assure that rapid cladding oxidation does not occur and drive the temperature beyond the limit. Reasonable limits on the short-term and long-term injection flows do not result in significant peak temperature differences. Additional supporting cases are presented in Tables A-4.20a and A-4.20b which demonstrate that the 8.75" diameter hot leg break is the limiting case for success criterion ADQ. "Ihe operator action delay time of 30 minutes produces a higher peak temperature than a 15 minute delay since the core is uncovered prior to depressurization and the longer uncovery time produces higher temperatures. For time delays less than 25 minutes, the core temperature is less than 1200*F.
A.4.4.2 NLOCA Success Criterion ADQ ADQ is the success criterion for manual full depressurization for the intermediate LOCA initiating event. The need for manual actuation of the depressurization system on the event tree path using ADQ is a result of the failure of both the core makeup tanks which generate the ADS signal, so short term makeup water is supplied by an accumulator. Long-term injection is supplied by at least one gravity injection line. The success configuration for success criterion ADQ is at least:
2 of 4 stage 4 ADS lines maximum operator action delay of 30 minutes after the CMT signal May 31,1995 g
g A-34 Illh-===
=
DRAFT A. MAAP4 Analyses to S:pport Success Criteria The assumptions for the baseline case (MAAP4 case x4g) are:
minimum ADS:
2 stage 4 lines a
containment isolation failure
=
minimum short term injection:
I accumulator e
l minimum long term injection:
1 gravity injection line operator delay time:
30 minutes after CMT signal e
limiting break size and location:
4.75" diameter hot leg break.
The MAAP4 results for the baseline and supponing cases for success criterion ADQ are presented in Tables A-4.21a and A-4.21b.
Baseline case x4g results in a peak core temperature of 969'F. This case denionstrates substantial margin to the 2200'F acceptance criterion and to temperatures at which rapid oxidation of the cladding is expected to occur.
Additional supporting cases are presented in Tables A-4.21a and A-4.21b which demonstrate that the 4.75" diameter break is the limiting case for success criterion ADQ. The operator action delay time of 30 minutes produces a higher peak temperature than the 15 minute delay since the core is uncovered prior to depressurization and the longer uncovery time produces higher temperatures. Hot leg break is assumed to be the limiting break location based on the results of MAAP4 analyses for ADQ MLOCA presented in section A.4.4.1 which produces similar results.
A.4.4.3 SLOCA Success Criterion ADT (PRHR Failure)
ADT is the success criterion for manual full depressurization for the small LOCA initiating event with PRHR failure. The need for manual actuation of the depressurization system on the event tree path using ADT is a result of the failure of both the core makeup tanks which generate the ADS signal, so short term makeup water is supplied by an accumulator. The small LOCA event results in a RCS pressure that is higher than the ADS stage 4 interlock pressure, however the interlock can be manually overridden to open stage 4 valves without first opening stage 1,2,or 3 ADS lines. Long-term injection is supplied by at least one gravity injection line. 'Ihe success configuration for success criterion ADT is at least:
2 of 4 stage 4 ADS lines maximum operator action delay of 30 minutes after the CMT signal The assumptions for the baseline case (MAAP4 case s6a4) are:
minimum ADS:
2 stage 4 lines containment isolation failure minimum short term injection:
I accumulator j
[ WB5tingh0Use h
A-35
a DRAFT
==
- 4. usip,in.ix, to s,, ort s ecess criteri=
minimum long term injection:
I gravity injection line operator d: lay time:
15 minutes after CMT signal e
limiting break size and location:
0.5" diameter cold leg break.
e De MAAP4 results for the baseline and supporting cases for success criterion ADT are presented in Tables A-4.22a and A-4.22b. Baseline case s6a4 results in no core uncovery.
This case demonstrates substantial margin to the 2200'F acceptance criterion and to temperatures at which rapid oxidation of the cladding is expected to occur. Additional supporting cases are presented in Tables A-4.22a and A-4.22b which demonstrate that the 0.5" diameter break is the limiting case for success criterion ADT. The operator action delay time of 15 minutes is assumed to be more limiting than the 30 minute delay (although neither uncovers the core) since any potential core uncovery would occur after ADS, and decay heat is higher at the earlier time.
A.4.4.4 SLOCA Success Criterion ADT (PRHR Success)
ADT is the success criterion for manual full depressurization for the small LOCA initiating event with PRHR success. The need for manual actuation of the depressurization system on the event tree path using ADT is a result of the failure of both the core makeup tanks which generate the ADS signal, so short term makeup water is supplied by accumulator. Long-term injection is supplied by at least one gravity injection line. The success configuration for success criterion ADT is at least:
2 of 4 stage 4 ADS lines maximum operator action delay of 30 minutes after the CMT signal The assumptions for the baseline case (MAAP4 case s8a4) are:
minimum ADS:
2 stage 4 lines
=
containment isolation failure e
minimum short term injection:
I accumulator e
minimum long term it.jection:
1 gravity injection line operator dele.y time:
15 minutes after CMT signal e
limiting break size and location:
0.5" diameter cold leg break.
The MAAP4 results for the baseline and supporting cases for success criterion ADT are presented in Tables A-4.23a and A-4.23b. Baseline case s8a4 results in no core uncovery.
This case demonstrates substantial margin to the 2200"F acceptance criterion and to temperatures at which rapid oxidation of the cladding is expected to occur. Additional supporting cases are presented in Tables A-4.23a and A.4.23b which demonstrate that the 0.5"
" "' 3 ' ' "
- E.- -
W westinghouse A-36
==
1
DRAFT A. MAAP4 Analyses to Support Success Criteria diameter break is th; limiting case for success criterion ADT. He operator action delay time of 15 minutes is assumed to be more limiting than the 30 minute delay (although neither uncovers the core) since any potential core uncovery would occur after ADS, and decay heat is higher at the earlier time.
A.4.4.5 SGTR Success Criterion ADT (PRHR Failure)
ADT is the success criterion for manual full depressurization for the SGTR initiating event with PRHR failure. The need for manual actuation of the depressurization system on the-event tree path using ADT is a result of the failure of both the core makeup tanks which generate the ADS signal, so short term makeup water is supplied by an accumulator. The SGTR event results in a RCS pressure that is higher than the ADS stage 4 interlock pressure, however the interlock can be manually overridden to open stage 4 valves without first opening stage 1,2,or 3 ADS lines. Long-term injection is supplied by at least one gravity injection line. He success configuration for success criterion ADT is at least:
2 of 4 stage 4 ADS lines maximum operator action delay of 30 minutes after the CMT signal The assumptions for the baseline case (MAAP4 case g16) are:
minimum ADS:
2 stage 4 lines containment isolation failure
=
minimum short term injection: I accumulator e
minimum long term injection: I gravity injection line operator delay time:
15 minutes after CMT signal break:
SGTR.
The MAAP4 results for the baseline and supporting cases for success criterion ADT are presented in Tables A-4.24a and A-4.24b. Baseline case g16 results in no core uncovery.
This case demonstrates substantial margin to the 2200*F acceptance criterion and to temperatures at which rapid oxidation of the cladding is expected to occur. An additional supporting case is presented in Tables A-4.24a and A-4.24b which presents the 30 minute operator action delay. The operator action delay time of 15 minutes is assumed to be more limiting than the 30 minute delay (although neither uncovers the core) since any potential core uncovery would occur after ADS, and decay heat is higher at the earlier time.
A.4.4.6 SGTR Success Criterion ADT (PRHR Success)
ADT is the success criterion for manual full depressurization for the SGTR initiating event with PRHR success. The need for manual actuation of the depressurization system on the event tree path using ADT is a result of the failure of both the core makeup tanks which
[ WB5tingt1Duse A-37
~
DRAFT A. MAAP4 Analyses to S:pport Success Criteria f
generate the ADS signal, so short term makeup water is supplied by accumulator. Long-term injection is supplied by at least one gravity injection line. 'Ihe secondary side is not isolated, otherwise the depressurization of the PRHR reduces the pressure below the secondary relief valve setpoirt and the loss of coolant is terminated and the sequence results in success. The success configuration for success criterion ADT is at least:
2 of 4 stage 4 ADS lines maximum operator action delay of 30 minutes after the CMT signal The assumptions for the baseline case (MAAP4 case gl7) are:
minimum ADS:
2 stage 4 lines containment isolation failure e
minimum short term injection: I accumulator e
minimum long term injection: 1 gravity injection line 2
operator delay time:
15 minutes after CMT signal break:
unisolated SGTR.
a l
The MAAP4 results for the baseline and supponing cases for success criterion ADT are presented in Tables A-4.25a and A-4.25b. Baseline case gl7 results in no core uncovery.
This case demonstrates substantial margin to the 2200'F acceptance criterion and to l
temperatures at which rapid oxidation of the cladding is expected to occur. An additional l
supporting case is presented in Tables A-4.25a and A-4.25b which presents the 30 minute operator delay which does not result in core uncovery. The operator action delay time of 15 l
I minutes is assumed to be more limiting than the 30 minute delay (although neither uncovers the core) since any potential core uncovery would occur after ADS, and decay heat is higher at the earlier time.
A.4.4.7 Transient Success Criterion ADT ADTis the success criterion for manual full depressurization for the transient initiating events.
'Ihe need for manual actuation of the depressurization system on the event tree path using ADC is a result of the failure of both the core makeup tanks which generate the ADS signal, so shon term makeup water is supplied by accumulator. Long-term injection is supplied by at least one gravity injection line. The success configuration for success criterion ADT is at least:
2 of 4 stage 4 ADS lines maximum operator action delay of 30 minutes after the PRHR signal ay 31, IM g
W WestirlbDtlSe A-38 Em,a--
==
1 i
DRAFT ro A. MAAP4 Analyses to S:pport Success Criteria I
~
.2 De assumptions for the baseline case (MAAP4 case t9a3) are:
minimum ADS:
2 stage 4 lines
]
contamment isolation failure minimum short term injection:
I accumulator f
=
minimum long term injection:
I gravity injection line operator delay time:
15 minutes after PRHR signal e
limiting break size and location:
0.5" diameter cold leg break.
ne MAAP4 results for the baseline and supporting cases for success criterion ADT are presented in Tables A-4.26a and A-4.26b. Baseline case 19a3 results in no core uncovery.
)
This case demonstrates substantial margin to the 2200*F acceptance criterion and to temperatures at which rapid oxidation of the cladding is expected to occur. Additional l
supporting cases are presented in Tables A-4.26a and A-4.26b which demonstrate that the operator action delay time of 15 minutes is more limiting than the 30 minute delay since any potential core uncovery occurs after ADS, and decay heat is higher at the earlier time.
f A.4.5 ADS Manual Actuation for Failure of Automatic Actuation The focus of the automatic depressurization system success criteria with at least one functional CMT is for automatic actuation, operator action is also credited in the event trees if the automatic depressurization system valves fail to open when the low core makeup tank level setpoint is reached. MAAP4 analyses of the automatic ADS baseline cases with delayed operation, presented in Table A-4.27a and A-4.27b, show the acceptable operator action time l
for most sequences after the low core makeup tank level setpoint is 30 minutes. He one exception is the small LOCA full depressurization case with PRHR failure (criterion ADA).
This case is quantified at the cutset level such that failure of the automatic actuation of the ADS for small LOCA full depressurization results in core damage.
A.5 Accumulator and Core Makeup Tank Success Criteria The success criteria for the accumulator and core makeup tank systems is that one of the tanks will inject water when the system actuation requirements are met. In the structure of the event trees, either accumulators or core makeup tanks are credited (but not both) for any given j
success path. He MAAP4 analyses to support the automatic depressurization system success criteria have also supported the accumulator and core makeup tank success criteria by modeling only one accumulator or one core makeup tank in the baseline analyses presented in section A.4 (subsection A.8.1 includes a discussion of analyses that assumed more than one core makeup tank or accumulator.) De accumulator success criteria that are addressed by MAAP4 analyses are ACIA and AC2AB. De core makeup tank success criteria that are i
[ WeSlingh0DSB A 39
y DRAFT A. MAAP4 Analyses 13 S:pport Success Criteria addressed by MAAP4 analyses are CM1 A, CM2AB, CM2L, CM2P, and CM2SL. However, success criteria AC2AB and CM2AB are not addressed by MAAP4 analyses for large loss-of-coolant accident and ATWS events, respectively.
In the core makeup tank success criteria, the core makeup tank is assumed to automatically actuate based on the core makeup tank actuation signals. (The core makeup tank actuation signals credited in MAAP4 analyses are listed in subsection A.1.2.) However,if automatic actuation fails, credit is taken if the operator is able to take action within a certain period of time. Results from the MAAP4 analyses determine what the acceptable time delay is. Table A-4.28a and A-4.28b present the MAAP4 baseline case results with successful CMT operation analyzed with the actuation of the CMT delayed by the maximum time credited in the event tree analysis.
The MLOCA event, because it causes the most immediate need for coolant inventory makeup, is the most restrictive of the analyses performed with MAAP4 regarding the acceptable delay in core makeup tank actuation. Smaller break sizes in the reactor coolant system result in slower loss of inventory, and thus longer delays in makeup inventory from the core makeup tank may be acceptable. When a MLOCA occurs, the core makeup tank actuation signal occurs within the first few seconds of the accident. The core makeup tanklevelis maintained for approximately 5 minutes while the core makeup tank operates in a recirculation mode.
in the recirculation mode, the cold water is injected to the downcomer through the direct vessel injection line, and the warmer water recirculates from the cold leg through the balance line to the top of the core makeup tank, maintaining core makeup tank level. When the top of the balance line uncovers, the recirculation mode ends, and the core makeup tank injects quickly. Herefore, while the core makeup tank is in the recirculation mode, it is not providing substantial coolant inventory make-up to the reactor coolant system. MAAP4 analyses show successful MLOCA results when the core makeup tank actuation is delayed by up to 10 minutes.
De acceptable delay in the opening cf the core makeup tank isolation valves, from the time of the actuation signal,is as follaws:
Medium loss-of-coolant accident - 10 minutes
=
Intermediate loss-of-coolant accident - 10 minutes Small loss-of-coolant accident - 20 minutes Steam generator tube rupture - 30 minutes Transients - 30 minutes
=
De one exception to these times is the SGTR full automatic depressurization case with PRHR failure. His case will be quantified at the cutset level such that failure of automatic actuation of the CMT will lead to core damage.
E.
W W85tiflgt101]Se
==/
A-40
-==
DR. AFT A. MAAP4 Analyses to Scpport Success Criteria A.6 Passive Residual Heat Removal Success Criteria The success criteria for the passive residual heat removal system is that one-out-of-two passive residual heat removal heat exchangers will function. The MAAP4 analyses for SLOCA and steam generator tube rupture with automatic depressurization system actuation have included cases that credit passive residual heat removal. The success criteria that are addressed by MAAP4 analyses are PRL and PRS. System responses from analyses that include the operation of the passive residual heat removal heat exchanger are discussed in subsections A.4.1.3, A.4.1.5, A.4.2.3, A.4.2.5, A.4.3.4, A.4.3.6, A.4.4.4, and A 4.4.6.
In the passive residual heat removal success criteria, passive residual heat removal is assumed to automatically actuated based on the passive residual heat removal actuation signals. (The passive residual heat removal actuation signals credited in MAAP4 analyses are listed in subsection A.I.2.) However,if automatic actuation fails, credit is taken if the operator is able to take action within a certain period of time. Results from the MAAP4 analyses determine that 30 minutes is an acceptable time delay to credit in the event tree analysis. Table A-4.29a and A-4.29b present the MAAP4 results of baseline cases with the operation of the PRHR delayed by 30 minutes.
l A.7 Normal Residual Heat Removal and In-Containment Refueling Water Storage Tank Success Criteria Long-term cooling of the core is provided by either the normal residual heat removal pumps or the in-containment refueling water storage tank gravity drain. The normal residual heat removal success criteria that are addressed by MAAP4 analyses are RNP and RNR. The in-containment refueling water storage tank gravity drain success criteria that are addressed by MAAP4 analyses are IWl A and IW2AB. However, success criteria RNR and IW2AB are not addressed by MAAP4 analyses for ATWS, and IW2AB is not addressed for large loss-of-coolant accident events.
The in-containment refueling water storage tank success criteria is for gravity injection to be provided through one direct vessel injection line. Representative MAAP4 analyses that include this model are discussed in subsections A.4.3 and A.4.4.
The normal residual heat removal success criteria is for injection to be provided from one normal residual heat removal pump. Representative MAAP4 analyses that include this model are discussed in subsections A.4.1 and A.4.2.
For the normal residual heat removal success criteria, the MAAP4 analyses assume that the operator has taken the necessary actions to align the normal residual heat removal system for operation by the time that the reactor coolant system pressure is below the normal residual heat removal pump shut-off head. This occurs the quickest in the MLOCA analyses, in which the normal residual heat removal pump shut-off head may be reached within approximately five minutes after accident initiation, when only one core makeup tank or one accumulator is credited. The baseline MAAP4 analyses take credit for the start of normal residual heat
[ WestinghDijse CEN-A-41
i DRAFT
,, y,un,iy,,, e sry, ort s.ccess criieri-removal injection at this time. Sensitivity analyses are done to determine the impact of delaying the start of normal residual heat removal. MAAP4 analyses presented in Tables A-4.30a and A-4.30b show successful MLOCA results when the normal residual heat removal operation is delayed until 30 minutes after the reactor coolant system break occur. Breaks at the smaller end of the MLOCA range ($ inch diameter) and smaller take longer than 30 minutes from the time of the break to depressurized below the RNS pump shut-off head.
For other initiating events analyzed with MAAP4, normal residual heat removal can be credited only after automatic depressurization system lines have been actuated. In most of the analyses, a reduced number of automatic depressudzation system lines is credited, and therefore the depressurization time until the normal residual heat removal shut-off head is reached may be longer than if all the automatic depressurization system lines opened.
However, there are a number of events that the operator could use to indicate that actions should begin to align the normal residual heat removal. Table A-9 lists the approximate times that it takes for the RCS pressure to fall below normal residual heat removal shut-off head after different indicating events in the sequences. The event tree analysis credits a delay time of 30 minutes from the CMT injection signal for the operator to actuate RNS.
A.8 Containment Isolation Containment isolation was questioned as a condition for long-term recirculation cooling to ensure an adequate water supply. The concern is for paths on the event tree in which passive injection works properly, but the containment is not isolated and water inventory is lost as steam through the opening. Calculations were performed to determine that there is sufficient inventory for at least 2.7 days to keep the top of the fuel covered with water, regardless of whether containment isolation is successful.
The calculation to determine the minimum time until inadequate water inventory would be a concern for long-term core cooling is based on the assumption that the entire inventory from the in-containment refueling water storage tank is emptied into the reactor and lower containment. The initial water volume from the reactor coolant system is neglected since much of it would have flashed to steam upon exiting the reactor coolant system. The inventory from the core makeup tanks and accumulators is also conservatively neglected. The water is assumed to boil off at a rate determined by the decay heat rate. With these factors, the top of the core remains covered for 2.7 days, assuming that there is no return of condensed steam from the containment shell.
A sensitivity on the above calculation is performed to determine the effect of condensate reflux from the passive containment cooling system cooling. The fraction of water that would be returned back to the containment water pool due to condensation of the containment shell is uncertain. Figure A-50 shows that as the condensation rate approaches the boiloff rate, the time to containment uncovery approaches infinity. Based on best estimate approximations, the reflux condensation from a dry passive containment cooling system shell is approximately 2 lbm/s (1 kg/s), leading to core uncovery in 3.5 days. The reflux condensation from a wet passive containment cooling system shell is estimated to be approximately 6.5 lbm/s (3 kg/s),
leading to core uncovery in 8.2 days. Nevertheless, the failure of containment isolation does May 31,1995 g
W Westi!EllDijse A-42 IE h a
==
DRAFT A. MAAP4 Analyses to S:pport Success Criteria not cause a water inventory concern for at least 2.7 days, conservatively assuming no reflux condensation.
Although containment isolation is not a concern for long term water inventory concerns,it can impact event sequences that rely on the in-containment refueling water storage tank gravity drain as the long term cooling source. For the in-containment refueling water storage tank to gravity drain into the reactor coolant system, the reactor coolant system pressure must decrease to within approximately 15 psi (1 bar) of the containment pressure. When the containment is not isolated, the containment pressure remains low, and the reactor coolant system pressure must decrease further than when the containment is isolated. Therefore the success criteria definitions are based on analyses that consider the limiting scenario of no containment isolation.
The analyses without containment isolation are discussed in Section A.9.
The isolation failure is assumed to be the largest single opening in the containment isolation system, which is the containment air filtration system line with an 2
18 inch diameter (area of 254 in ),
A.9 Sensitivity Analyses Sensitivity analyses of the success criteria baseline cases are performed to demonstrate the robustness of the success criteriain terms ofinteractions with other passive and active systems and uncertainties related to the thermal-hydraulics of the system and modeling in the codes (passive system performance). The sensitivity analyses are presented in this section.
A.9.1 Systems Interactions
[LATER - this section will be completed as part of the thermal-hydraulic uncertainty tasks]
A.9.2 Passive System Performance
[LATER - this section will be completed as part of the thermal-hydraulic uncertainty tasks]
A.10 MAAP4 Results
[LATER - this section will be completed as part of the thermal-hydraulic uncertainty tasks]
A.11 References A-1 EPRI Project 3131-02, "MAAP4 - Modular Accident Analysis Program for LWR Power Plants - Computer Code Manual," Rev. O, May 1994.
A-2 EPRI TR-100743, "MAAP PWR Application Guidelines for Westinghouse and Combustion Engineering Plants," June 1992.
l A-3
" Advanced Light Water Reactor Utility Requirements Document," Volume III, l
Chapter 1. Appendix A, Revisions 5 & 6, December 1993.
)
l
""# 3""
W wesinghouse Pm 3 43
DRAFT A. MAAP4 Analyses to Support Success Criteria Table A-1 ACTUATION AND TRIP SIGNALS USED IN AP600 MAAP4 ANALYSES System Trip or Actuation Signals Low pressurizer pressure Reactor Trip Low pressurizer level Low SG narrow range level CMT actuation signal CMT actuation signal Reactor Coolant Pump Trip Low-l CMT level ADS Actuation (Stage 1,2,3)
!.ow-2 CMT lesel: RCS pressure must ADS Actuation (Stage 4) be icas th.m 1000 psia for automatic actuation Low-2 pressurizer level CMT Actuation Low SG wide range level with high hot leg temperature Low-l pressurizer pressure High-1 containment pressure Low steamline pressure Low-3 cold leg temperature Low SG narrow range level with low PRHR Actuation SFW flow Low SG wide range level CMT actuation signal RCS pressure less than 700 psia Accumulator Injection RCS pressure less than 175 psia NRHR Injection Pressure difference between RCS and IRWST Gravity Drain containment is approximately 15 psia
""# 3**
fu T westinghouse 3
44
DRAFT A. hfAAP4 Analyses to S:pport Success Criteria Table A-2 RCS PRESSURE REQUIREhfENTS FOR LOCA CATEGORIES LOCA Category Functional Definition Required RCS Pressure Large IRWST gravity drain
- 50 psia (RCS to containment AP of-15 psia)
Medium NRHR shutoff head 5175 psia Intermediate Fourth-stage ADS line can open s 1000 psia without PRHR or earlier stage ADS Small Founh-stage ADS line cannot
> 1000 psia open without PRHR or earlier stage ADS Note:
To define the break size that corresponds to each LOCA category, MAAP4 analyses were done to determine the RCS pressure response prior to core uncovery. The resuhs from these cases are summarized in Table A-3.
WB5tinghDUSS Mi==
A-45
DRAFT A. MAAP4 Analyses to Support Success Criteria Table A-3 IIREAK SIZE DEFINITION, NO ADS RCS Pressure at Core Uncovery Pipe ID (in)
(Bars)
(psia)
Initiating Event 1
132.8 1926 SLOCA 1.75 72.56 1052 2
66.91 970 NLOCA 3
32.29 470 4
18.11 263 4.75 12.61 183 5
11.40 165 MLOCA 6
7.85 114 7
5.69 83 8
4.33 63 8.75 3.73 54 9
3.58")
52")
LLOCA Note:
Pm W men 3
4g i
1
~
DRAFT A. MAAP4 Analyses to Srpport Success Criteria Table A-4
SUMMARY
OF ADS SUCCESS CRITERIA DEFINITIONS SUPPORTED BY MAAP4 ANALYSES Heat Removal /
MAAP4 Case Name for lajectkm Method Applicable Initiating Events Success Depress.
Criteria Description of Short 1.eng Method Name Soccess Criteria Term Term MLOCA NLOCA SLOCA SGTR Trans PARilAL ADU Automade Actuadon:
zib 2/2 stage 1 OR 1/8 stage 23.4 CMT NRHR ADIA Automade Actuadon:
s16k 310m tl ADRA 2/2 stage 1 OR 1/4 stage 23 CMT NRHR ADV Automanc Actuadon:
PRHR s10 gli 1/10 stage 1,23,4 CMT NRHR ADUM Manual Actuadon:
x2h s19b2 gl2d 13h ADI 2/2 stage 1 ADR OR 1/8 stage 23,4 Accum NRHR ADZ Manual Actuadon:
PRHR sl3 gl3 1/10 stage 1.23.4 Accum h1HR Ft'll ADM Automanc Actuadon:
m3g4 x3d4 2/4 stage 4 CMT IRWSf" ADAB Automanc Actuadon:
sit 2 t5t ADAL 3/4 stage 2,3 ADA OR 1/4 stage 2.3 and 1/4 stage 4 CMT IRWST*
ADAG Automade Actuation:
gl4e 1/4 stage 23 and 1/4 stage 4 CMT IRWSf" ADS Automanc Actua6on:
s42 g15 3/4 stage 23 OR PRHR 1/4 stage 4 CMT IRWSf" ADQ Manual Actuation:
m6e5 x4g 2/4 stage 4 Accum IRWSf" ADB Manual Actuadon:
s6a4 g16 19a3 ADL 2/4 stage 4 ADT Accum IRWSf" ADT Manual Actuadon:
PRHR s8a4 gl7 2/4 Stage 4 Accum IRWSf" M:
1.
IRWST gravity drain or normal residual heat removal can provide long term injec6on and heat removal, but IRWST gravity drain is more linu6ng for ADS success cntena, and therefore is modeled in the MAAP4 analyses.
[ W85tinghDUSS Mtb.
A-47
3 Q
w Table A-4.la MAAP4 Analyses Supporting ILOCA Success Criterion ADU ta Case Equipment Assumptkes Mas y
~
Core Temp maap Run Type 1
2/3 4
M CMT ACC PRIIR NRIIR IRWST Sensitivity Definition
(*F) utb baselme 2
1 I pump 2* coki leg 1147 alc support 1
I 1 pump 2* cokileg no smcov ald support 1
I l pump 2* coki leg no uncov sla support I
I 1 pump 4.75* coki leg no uncov utb3 support 2
t I pump stuck SV 810 mib4 support 2
I I pump 2* hot leg 1075 xid2 support 1
1 I pump 2* hot leg 581 A
Table A-4.le SEQUENCE OF EVENTS FOR ILOCA SUCCESS CRITERION ADU MAAP4 ANALYSES K
Grr Isdection S: art et irgection Accum. Inj (sed (sec)
Openerat of ADS Valves (m)
(sect "
Core Uncovery
- N Peak Start Min Water Level (%)
Temp Case start Empty Start Empty 1
2 3
4 NRIIR IRWST (seo at Thee (sec)
(*F)
(
w g
alb 51 3367 2256 4788 4274 52% e 4778 1147 alc 51 3377 2492 30 %
g uld 51 1499 3629 38 %
[
als 7
IC 803 1367 31 I
nib 3 3057 5815 4694 7174 6934 74% te 7235 810 alb4 75 3371 2285 4392 3991 56 % @ 43 %
1075 a
n5 mid2 75 33H) 3670 2829 3794 86 % @ 3891 810 m
- 1E O
cu g
Tunes for the start of NRHR IRWST core uncovery mi mmunum water level are from MAAP4 output that does not capture output at every tunestep. Therefore-
- 2-C 8
the times Irsted in these sections are not exact and typrally may differ from the actual analytral predstion by 2l00 secoruls
K>
g Table A-4.2a to MAAP4 Analyses Supporting SLOCA Success Criterion ADI A 21 E
Case Equipment Assumptions l
g Max q
C3 ADS Core lC C
masp Temp m
N run type 1
2/3 4
M CMT ACC PRIIR NRIIR 1RWST Sensitistty Ikfinition
(*F)
F sl6k baselme 2
I I pump 0.5* hot leg 1284
-q sl7 support 1
1 I pump 0.5* cokt leg 561 32 sl6 suupwt 2
I 1 pump 0.5* coki leg 1261 m
e l
sl6c suppwt 2
I I pump 1.75* cokt leg i176 8
3" sl6c2 supput 1
1 I pump 1.75* coki leg in uncov a
4F D
en Table A-4.2b SEQUENCE OF EVENTS FOR SLOCA SUCCESS CRITERIGN ADIA MAAP4 ANALYSES CMT lejectlam Start et Inqlectlen Accuen. IQ (sec)
(sec)
Opening of ADS Valves (sec)
(sec)
- Core Uncovery
- Peak Start Min Water 14,el(%)
Temy case Start Empty Start Empty 1
2 3
4 NRHR IRWST (sect at "Iline (sec)
(*F) sl6k 1290 14520 13678 15234 14110 32 % # 15220 1284 sl7 830 14380 13823 14424 13980 66 % 9 14480 861 sI6 830 14480 13584 15148 14080 33 % @ 15190 1261 sl6c 57 3896 2769 5325 4805 49% e 5308 1176 sl6c2 57 3895 2888 3583 34 2
l Emme 8
Tunes for the start of NRilR, IRWST core uncovery and minimum water level are from MAAP4 output that does not capture output at every timestep. Therefore.
the times listed in these sections are not exact aral typically may differ from the actual analytical prediction by tt00 secteds
a I
0 2
Table A-4.3a i
M AAP4 Analyses Supporting SLOCA Success Criterion ADV tn Caw Equipment Ammmptions ADS Core masp Temp run type 1
2/3 4
M CMT ACC l'RIIR NRIIR 1RWST Sensitivity Dennition
(*F) s10 baselme 1
1 Yes I pump 0.5" coki leg ry2 uncov siI support I
1 Yes Ipump 0.5" cold leg no uncow s12 suppret 1
1 Yes I purnp 0 5* cold leg no uncov sloa support I
I Yes I pump 1.75* cold les no uncow u,
Table A-4.3b P
SEQUENCE OF EVENTS FOR SLCOA SUCCESS CRITERION ADV MAAP4 ANALYSES g>
CIWT Injectlen Start of injection Acam Inj (m)
(m)
Opening of AIRS Valves (sec)
(m)
- Core Unrevery
- A Peak y
Start Min Wat * & 4 (%)
Temp p
Case Simrt Empty Start Empty 1
2 3
4 NittIR IRWST (sec) as T e v.
(T)
W y
slo 830 38219 38684 h
sli 830 39430 38458 38830 O
cn st2 810 45750 45I45 45241 y
slo.
57 3308 3131 3a 5
n a,
n9 n
8 B-a Tunes for the start of NRHR, IRWST core uncove:y and minimum water level are from MAAP4 output that (km not capture output at every tunestep. Therefore, j-gw the times listed in these sections are not exact ard typically may difTer from the actual analytical pratrtion by 21(0 seconds 4
0
Y l$
=
Table A-4.4a g
MAAP4 Analyses Supporting SGTR Success Criterion ADI A 2
Cow Equipment Assumptisms ADS Core y
masp Temp 8
run type 1
2/3 4
M CMT ACC PRilR NRHR IRWST Sensitivity Definition CF)
G o
g10a baselme 2
1 I pump SGTR 1809 r.n a
g10c support 1
1 I pump SGTR no uncov h
3 T
a En 3-ET d
?
tn Table A-4.4b SEQUENCE OF EVENTS FOR SGTR SUCCESS CRITERION ADIA MAAP4 ANALYSES
~
cMrr Inyce start.f inque.n Acasm. Inl (sec) tsee)
Opeedrig of ADS Valves (see)
(sec)
- Core thcovery
- Peak Start Min '"ater level (%)
Temp Case Start Empty Start Empty 1
2 3
4 NRHR IRWST (sec) at 'I1sne (see)
(*F) g10a 115 13650 12650 16434 15660 49 % @ 16470 1109 gioc 115 13750 12882 14217
$4 E
l Times for the start of NRiiR. IRWST core uncovery and minimum water level are from MAAP4 output that does not capture output at every tunestep. Therefore, the times listed in these sections are not exact and typically may differ frein the actual analytical prediction by t t00 secimds m
?
l 4
[
Table A-4.5a MAAP4 Analves Supporting SGTR Success Criterion ADV 8
m Cow Equir ment Amumptions ADS Core maap Temp run type I
2/3 4
M CMT ACC PRIIR NRilR IRWST Sensitivity Definition
(*F) gIl bescime I
I Yes I pump SGTR no sec isol no uncov glia support 1
1 Yes I pump SGTR no see isol no uncov gilb support 1
I Yes I pump SGTR no sec isol no uncow
)
tn Table A-4.5b SEQUENCE OF EVENTS FOR SGTR SUCCESS CRITERION ADY MAAP4 ANALYSES K
CMT Injection Start of leqjection Accama. In)(wc)
(sec)
(W et ADS Valves (sec)
(sec)
- Core Uncovery
- g 1"
Pesk Start hiin Water Isvel(%)
Tenip Caw Start Emipty Start FJupsy 1
2 3
4 NRilR IRWST (sec) at Thee (sec)
(*F)
Ea stil 100 2758 g
a g1Is 100 2758 g
gilb 100 2758
[
1 3a er I
to R
n 3
5 c
C N
Tunes for the start of NRilR,IRWST care imcovery amt minunum water level are from MAAP4 output that does not capture output at c ery timestep. Therefore, the tunes listed in these secuons are not exact and typically may differ from the actual analytical preda: tion by 1100 seconds E
b a
---.w
a 3>
Table A-4.6a g
MAAP4 Analyses Supporting Transient Success Criterion ADIA g
Caw Equipment Assumptions Core g
ADS Temp
=
g masp run type 1
2/3 4
M CMT ACC PRIIR NRilR 1RWST Sensitivity Definition
(*F)
E tl baseline 2
1 I pianp Transient 1305
'e t2 support 1
- l 1
I pianp Transient 832 3
h
}
E R
3 at
(")
E-4F Y
wW Table A-4.6h SEQUENCE OF EVENTS FOR TRANSIENT SUCCESS CRITERION ADIA MAAN ANAL,YSES CMT bqection Start of injection Accum. Ird (sec)
(sec)
Opening of AIE Valves (sec)
(sec)
- Cere Uncovery
- Peak Start Min Water level (%)
Temp Case Stort Empty Staat Empty 1
2 3
4 NRHR IRWST (sect at Tinte (sec)
(*F) tl 4698 10080 90 %
10842 10080 35 % # 10890 1305 s2 4698 9970 9336 9994 9569 73 % 9 9769 812
=
'-ll l
8 Times for the start of NRilR,IRWST core uncovery and minimum water level are from MAAP4 output that does not capture output at every tunestep. Therefore, m
the times listed in these sechoes are twW exact and typically may differ from the actual analytical predsction by itX) secimds
i r
I a
y 1
j Table A-4.7a
}
h1AAP4 Analyses Supporting NLOCA Success Criterion ADUh1 l
Caw Equipment Assumptions ads Core j
maap Temp i
run type 1
2/3 4
M CMT ACC PRIIR NRHR IRWST Sensitivity Definition
(*F) l x2h baselme 2
M 1
1 pump 2* hot leg ADS @ 15 mm 1827 m2f support 1
M I
1 pump 2* coki leg ADS @ 15 min nn uncov m2g suppwt I
M I
Ipump 2" cokileg ADS @ 15 min rm uncov x2e support 2
M 1
I pump 2* cokileg ADS @ 15 mm litX) x2e2 suppwt 2
M 1
I pump 2* cokileg ADS @ 30 min R57 x2h2 suppet 2
M I
I pump 4.75* luu leg ADS @ 15 min rn uncov x?h3 surtwwt 2
M 1
1 pump 4.75* hot leg ADS @ 30 min 980 f
m2h4 support 1
M I
I pump 4.75* hot leg ADS @ 30 mm 964 x2h5 support 1
M 1
I pump 4.75* hot leg ADS @ 30 964
?
f Table A-4.7b SEQUENCE OF EVENTS FOR NLOCA SUCCESS CRITERION ADUh151AAP4 ANAINSES
>m q
CMT ledectlan S* art et lajedian e
Actuai. In) (sec)
(see)
Opening of ADS Valves (sec) teec)
- Core IJncovery
- E resh
-y Start Min Water level (%)
Teemp 3
Case Stan Empty Start Empty 1
2 3
4 NRHR 1RWST (sec) at Thee #sec)
(*F) o m2h 1318 4807 974 3249 1519 77 % @ 3244 1827 gc m2f 1145 2752 951 1560
'O s2g 1045 1341 951 1204 s2e 1347 4745 951 3338 1751 78 % & 3265 1800
[
Y R
g--
m2e2 2080 4800 1851 4140 3304 85 % # 4112 857 g
m 3
m2h2 512 1545 912 1203 n
3.
O m2h3 512 2053 1812 1835 923 83 % # 1742 983 m2h4 512 1994 1812 1821 923 82 % @ 1742 964 E
a2h5 512 1%5 1812 1816 923 82 % @ 1742
%4 Tunes for the start of NRHR. IRWST sxwe uncovery and minimum water level are from MAAP4 output that does not capture output at every timestep. Therefore.
the tim-* hsted m these sections are not exact and typically may differ from the actual analytral predstion by 100 seconds G
Table A-4.8a MAAP4 Analyses Supporting SLOCA Success Criterion ADI 2
reN 8.5 Case Equipment Assumptions Mas 5
g 5
ads Core E
c masp Temp I
run type 1
2/3 4
M CMT ACC PRIIR NRilR IRWST Sensitivity Definition
(*F) o sI9b2 baselme 2
M 1
I pump 0.5" hot leg ADS @ 15 mm 1266 y
T s20 support 1
M 1
I pump 0.5" cokt leg ADS # 30 min no uncov
]
s21 suppwt 1
M I
I pump 0.5" cok! leg ADS @ 30 mm no uncov h
s19b suppnet 2
M I
I pump 0.5" cold leg ADS W 15 min 1263 3
sI9 support 2
M 1
I pump 0.5" cold leg ADS @ 30 min 1144 in O
s19h support 2
M 1
I pump 1.75" cokileg ADS @30 min 1017 g
a s19:
support 2
M I
I pump 1.7" hot leg ADS W 30 min 1029 g
sl9k support 2
M I
I pump 1.75" hot seg ADS @ 15 mm 1170 g
u, m
Table A-4.8b SEQUENCE OF EVENTS FOR SLOCA SUCCESS CRITERION ADI MAAP4 ANALYSES c wr w on.n stan or wen.n Accum Inj (sec)
(sec)
Opening er ADS Valves (sec)
(sec)
- Care Usavery
- Peak Start ML Waaer Level (%I Teasp Cane Start Fmpty Start Fmpty 1
2 3
4 NRHR IRWST (sec) at linie tsec)
(*F) 2963 68% e 5289 1266 s19b2 2861 9701 2190 5289 i
s20 2864 4768 2(30 3370 s2I 2764 3072 2630 29I8 s19b 2449 9256 I?)0 4828 2549 70% W 4627 1263 sI9 3273 9367 2630 5744 3676 74 % @ 5698 1844
?p s19h 2178 5561 1861 4281 2990 81 % @ 4202 1017 s19i 2175 5541 1901 4205 2478 80% e 4202 1029 sI9tt 1434 5442 1001 3439 1535 76% e 3258 1870 Times for the start of NRiiR, IRWST core t acovery and minimum water level are from MAAP4 output that does not capture output at every tunestep. Ihcrefore.
the times bsted in these sections are not exact armt typically may differ from the actual analytical predaction by 100 seconds
g
)
i 34 ts i
Table A-4.9a MAAP4 Analyses Supporting SI,0CA Success Criterion ADZ
(#s Case Equipment Assumptions ADS Core mesp Temp Run type 1
2/3 4
M CMT
?CC PRIIR NRIIR 1RWST Sensitisity Definition
(*F) st3a baselme 1
M i
Yes 1 pump 0.5" cold leg ADS w 15 mm rm unwov sI4 support 1
M I
Yes I pump 0.5" cold leg ADS @ 30 min in uncov p
sida support 1
M 1
Yes I pump 0.5" cokileg ADS @ 30 min in tunvy 31 3 support M
I Yes I pump 0.5" cokileg ADS W 30 min no uncov sl3g support I
M I
Yes I pump 1.75" coki leg ADS @ 30 em uncov Table A-4.9b
?
SEQUENCE OF EVENTS FOR SLOCA SUCCESS CRITERION ADZ MAAP4 ANALYSES E
chrr injecuon stari.f ing co.n Acesias. Inj (sec)
(sec)
Opening of ADS Valves (sec)
(sec)
- Core Uncovery
- k h
5 I
Pesh y
Start kein Water level (%)
Temp a
Case Start Empty Start Fanpty 1
2 3
4 NRilR IRWST (sec) at ilme esec) rF) k st3a 2149 6307 1730 3326 si4 2475 3430 2630 3148 8
Ce sl4a 2475 1031 2630 2870 g
st3 2475 2630 4588 st3g 929 1857 3264 h=
s R
=
2 21-m l
g if g
Tunes for the start of NRHR, IRWST core uncovery and minimum wate level are from MAAP4 output that does not capture output at every timestep. Timcfore,
[
the times hsted in these secuons are not exact and typically may differ fre n the actual analytical prediction by 2l00 seconds l
1 1
l
E s
Table A-4.10a MAAP4 Analyses Supporting SGTR Succes, riterion ADI 2
Case Equipment Assumpthms S
ADS l
Core T
E masp i
Temp 2
run type 1
2/3 4
M CMT ACC PRil NRilR 1RWST Sensithity I)efinition
('F)
[
g o
gl2d baahne 2
M I
1 pump SGTR ADS @ 15 min 1034 y
gI2b suppwt I
M 1
I pump SGTR ADS @ 15 min nu uncov gl2e support 2
M 1
I pump SGTR ADS @ 30 min 977 k
g12c surgwt 1
M I
1 pump SGTR ADS @ 30 min no uncov 3
u O
- 2.X
-i IT Table A-4.10b SEQUENCE OF EVENTS FOR SGTR SUCCESS CRITERION ADI MAAP4 ANAI,YSES Chfr ledectka Start of lidectlen Accen.. EM (sect (see)
Opening of ADS Valves (sec)
(sec)
- Core Uncovery
- Peak Start Min Water level (%)
Temp Case Start Empty Start Empty 1
2 3
4 NRHR 1RWST (sec) at Thne (sec)
(*F) gl2d 1618 10582 1015 7800 6362 77 % @ 7879 1034 gl2b 1816 1522 1015 Illi gl2e 2438 10893 1915 8530 7373 80% # B681 977 gl2c 2034 2341 1915 2171 g
k y
l DES Tunes for the start of NRHR, IRWST core uncovery and minimum water level sie from MAAP4 output that does not capture output at every timestep. Therefore.
[
the times listal in these sec6ons are not exact ami typically may differ from the actual analytical predec60n by 1100 seconds I
(n
v P
W w
~
Table A-4.lla MAAP4 Analyses Supporting SGTR Success Criterion ADZ Caw Equipment Assumptions ADS Cor1r maap Temp run type 1
2/3 4
M CMT ACC PRIIR NRilR 1RWST Sensithity Definition CIO g13 baschne I
M I
Yes I pump SGTR ADS W 15 min no see isol ontarov gl3a support I
M 1
Yes 1 pump SGTR ADS @ 30 min, no see isol notuavv l
Table A-4. lib P
SEQUENCE OF EVENTS FOR SGTR SUCCESS CRITERION ADZ MAAP4 ANAI,YSES chrr wecc.n sian.f in,%
Accum. Irij (sec)
(sec)
Opening of AIM Vulves (ser)
(see)
- Ceee Uncovery
- Peak Start Min Water Istel(%)
Temp k
Cue Start Empty Start Empty 1
2 3
4 NRHR IRWST (sect at %ne esec)
(T) v g13 515 284l 1000 2424 g
g13a 515 2%7 1900 2534 I
a en h
1 n
a'n 3
h l
8 e
Times for the start of NRilR. IRWST core uncovery and minimum water level are from MAAP4 output that does not capture output at every tunestep. Therefine.
3.
the times listed in these sections are not exact and typically may differ frorn the actual analytical predstion by 2l00 seconds e
I 1
l(
x Table A-4.12a MAAP4 Analyses Supporting Transient Success Criterion ADI 2
n
- g-Caw Equipment Assumptions ADS C8*e
}
t-mesp lemp g
nas ty pe 1
2/3 4
M CMT ACC PRIIR NRilR IRWST Sensitivity Definition CF) g Oh baselme 2
M 1
I pump Trans ADS @ 15 min 12tto
[
t t4a support 1
M 1
I pump Trans ADS @ 15 min nu emcov
]3 t4c suppwt 1
M 1
I pump Trans ADS @ 15 min no uncor m
h Oi suppwt 2
M 1
I pump Trans ADS @ 30 min 1152 t4b support I
M I
1 pump Trans ADS @ 30 min saiuncov O
I4d support I
M 1
I pump Trans ADS @ 30 min no uncow 4F
?
1 vs I
e Table A-12b SEQUENCE OF EVENTS FOR SUCCESS CRITERION ADI MAAP4 ANALYSES cntri.ono.n start or iguuon Accum. Ird (sec)
(sec)
Openhag of ADS Valves (see)
(sec)
- Core Uncovery
- Peak i
Start Min Water Level (%)
Temap Came Naart Eanpty Start Empty 1
2 3
4 NRHR IRWST tsec) at T1rne (sec)
(*F) 83h 1735 9039 960 4147 1836 69 % @ 4269 1280 t4a 1332 3784 960 1829 t4c II29 1431 960 1273 Eh 2559 9177 1860 5095 2963 73% # 5085 1152 E4h 2153 5031 1860 2684 3
e4d 2052 2319 4
18m 2159 2d M
Times for the start of NRIIR,IRWST unre uncovery and minimum water level are from MAAP4 output that does not capture output at every tunestep. Therefore, til the times listed in these sections are not exact and typically may antles ~.mm the actual analytical prediction by 1100 seconds
3 Q
w Table A-4.13a MAAP4 Analyses Supporting MLOCA Success Criterion ADM i
Us Caw Equipment Amumptions i
Mas q
aOS Cott maap Temp run type 1
2/3 4
M CMT ACC PRIIR NRIIR IRWST Sensitivity Definition
('F)
Q m3g4 baselme 2
1 I hne 5' coki leg. no Cl rn mwow m3n) su m wt 2
1 I Ime 5 Imt leg. no C1 onwww h
m3r3 suppwt 1
1 1 Ime 8.75" hot leg. no Cl no uncov mea 3 suppnt 2
1 I kne DVI line, no Cl no uncov e
Table A-4.13b SEQUENCE OF EVENTS FOR MLOCA SUCCESS CRITERION ADM MAAP4 ANALYSES m
CMT trQectlen Start of lajection Accom. Inj (see)
(see)
(W of AlW Yelves (see)
(m)
- Core Uncovery
- h h
g Start Min Watee 1svet (%)
Temp k
Cue Start Empty Start Ernpty 1
2 3
4 NRHR IRWST (sec) at Time twc)
(*F) w mig 4 7
1940 1398 2151 g
m'la3 II 1846 1386 1872 E
m3r3 3
1615 1848 1647 m4 3 Il 2162 1537 2342 3
I a
en 9.
2 3
Tunes for the start of NRHR, IRWST core uncovery arm! mimmum water level are from MAAP4 output that does not capture output at every tunestep. Therefiwe.
h the times hsted in these sections are not exact armi typically may differ from the actual analytical prediction by 1100 seconds O
Table A-4.14a MAAP4 Analyses Supporting NLOCA Success Criterion ADM 2
14 a:g-Caw Equipment Amumptions g
Core T
ADS E
maap Temp l
run type I
2/3 4
M CMT ACC PRIIR NRifR IRWST Sensitivity Definition
(*F) g g
x3d4 baseline 2
1 I kne 2" hot leg. no CI 959 y
z x3b support I
I I hne 2" hot leg 1230
]
13a support 1
1 1 ime 2" cold leg 545 k
x3j5 support 2
I I hne 4.75" cold leg. no CI nn uncov 3
u O
E 4
Er D
cn Table A-4.14b SEQUENCE OF EVENTS FOR NLOCA SUCCESS CRITERlON ADM MAAP4 ANAL,YSES CMT Injecthm Start of Irdection Accum. Inj (sec)
(wc)
(1pening af ADS Valves (sec)
(sec)
- Core Uncovery
- Peak Start Mia Water level (%)
Tensp Case Start Fmpty Start Empty 1
2 3
4 NRilR IRWST (sec) at Thee (sec)
(T) m3d4 73 3391 3771 4024 3792 45 % # 3902 959 m3b4 75 3390 3670 4095 3791 39 % @ 4092 1230 m3a 51 2499 3670 4755 4633 85% 8 4734 545 m3j5 7
1958 142R 2247 E4 5
- Times for the start of NRHR. IRWST core uncovery and minunum water level are from MA AP4 output that does not ca'pture output at every timestep. Therefore, the times hsted in these sections are not exact and typically may differ from the actual analytu;al prediction by 1100 seconds tsi
E4 i
S:
Table A-4.15a
}
MAAP4 Analyses Supporting SLOCA Success Criterion ADA Caw Equipment A=umpthms Mas ADS Core manP Tetup run type 1
2/3 4
M CMT ACC PRilR NRIIR IRWST Seesitivity Definition (T) sit 2 bascime 3
I I kne 1.75* coM leg. no CI 1534 Q
s3b7 su m ut 1
1 I
1 Ime 1.75" cold leg no Cl 1285 sit 4 su m ut 3
I I kne 1.75* hat leg. no CI 1493 s3b2 su m et 1
I 1
I kne 0.5 cuki leg. no CI i176 slu2 suppet 3
I I kne 0.5 hot leg, no Cl 1220 g
sit 6 sens 3
I I kne 1.75* coki leg, no Cl. min grav inj 1588 sit 7 sens 3
I I hne 1.75" cokt leg. no Cl. min CMT flow 1514 Table A-4.15b D
SEQUENCE OF EVENTS FOR SLOCA SUCCESS CRITERION ADA MAAP4 ANALYSES g
Cur i,o-o.n san.ti.o-o.n C
m Acc.s-t tro (see)
(see)
Opening of ADS Valves (m)
(sec)
- Core Uncovery *
"U
'A 4
Peak mrt Min Water tsvel t%)
Temp g
Caw mrt Empty Wrt Empty I
2 3
4 NRHR IRWST (sec) at Thee (sec)
(
- F) y sit 2 57 3814 2910 3031 5108 4617 59% W 5119 1534 s3b7 57 3918 3031 3428 4868 4522 69% W 4925 I285 sli4 100 3813 2931 3051 4848 4415 61% W 4917 1493 s%2 830 14340 13741 13939 14475 13940 42% w 14440 1876 stu2 1249 14460 13895 14015 14650 14060 a9% w 14660 1220 M
1 I
N l
sit 6 59 3793 2917 3037 5101 4595 57% W 5097 1588 y
E sit 7 57 3991 2921 3040 5295 4794 59 % # 5295 1514 I
O
\\
~
C S
- Times for the start of NRilR. IRWST core uncovery and minimum water level are from MAAP4 output that does not capture outpst at every tunestep. Therefore.
F the tames hsted m these sections are not exact aimi typically may differ from the actual analytral predstion t'y 2l00 sectumis 6
L-
Table A-4.16a k
MAAP4 Analyses Supporting SLOCA Success Criterion ADS 2
2 l
I Case Equipment Assumptions g
hlas g
q cp ADS
(, ore g
C maap Temp
=
run type 1
2/3 4
M CMT ACC PRIIR NRIIR IRWST Sensitivity Definition
(*F) g s4z baselme 3
I Yes I line 1.75" hot leg. no Cl 1273 93 s4b2 support 1
I Yes I line 1.75" cokt leg, no Cl no urrov 3
s4b suppwt 3
1 Yes I kne 1.75" cok! leg 10 9 m
a s4tl support 3
1 Yes I line 1.75* hot leg 1080 8
3*
s4gl support 3
1 Yes Iline 0.5" hot leg, no Cl 656 O
s4g suppwt 3
1 Yes I line 0.5" hot leg 1091 E
4 s4z2 suppet 1
1 Yes Iline 0.5" coki leg, no Cl no utrov g-O Table A-4.16b SEQUENCE OF EVENTS FOR SLOCA SUCCESS CRITERION ADS MAAP4 ANALYSES CMT Injection Start of tidection Accum. led (sec)
(sec)
(W of ADS Valves (sec)
(sec)
- Core Uncovery
- Peak Start hun Water Level (%)
Temp Cue Start Dnpty Start Empty I
2 3
4 NRifR IRWST (sect at Time (sec)
(*F) s4z 100 5001 4104 4224 6570 6203 73% e 6603 1274 s4b2 57 5210 4689 6176 s4b 57 4892 3951 4071 6598 6395 82% w 6695 1058 s4al 101 4998 4092 4212 6447 6200 80 % @ 6501 1080 s4:1 1249 43350 42644 42754 45495 45350 88% W 45550 656
- /p s4g 12 %
39480 38568 38688 42431 41580 64 % @ 42690 1991 s442 830 43000 42590 43926
.N Tunes for the start of NRilR IRWST core utrovery and minimum water leve! are from MAAP4 output that does not capture output at every tunestep. Therefore.
the times listed in these sections are not exact and typically may differ from the actual analytical prethetion by 1100 seconds
E I
a 2:L Table A-4.17a MAAP4 Analyses Supporting SGTR Success Criterion ADAG us Caw Equipment Ausmptions ADS Core manP Temp run type 1
2/3 4
M CMT ACC PRilR NRIIR IRWST Sensitisity I)erinition (F) gl4e baseline 1
I 1
I kne SGTR, no CI 685 23>
l e
Table A-4.17b SEQUENCE OF EVENTS FOR SGTR SUCCESS CRITERION ADAG MAAP4 ANALYSES g>
Chrt hqnts n start et treats n y
Anum. Inj tsect (sul thedng of ADS Vahes (m)
(m)*
Care (Jacovery *
]
Peak Start Min Water Isvel(%)
Tesny Case start Empty Start Empty 1
2 3
4 NRIIR 1RWST (sa) at T1rne (sec) rF) y side 116 13770 12926 133M 16317 16080 81% Ee 16380 6a3 E
,E 1
72
- E
=
n 2
E,.
m O1 cp C
- s N
Turnes for the start of NRiiR, IRWST core uncovery and minimum water level are from MAAP4 output that thws not capture output at every timestep. Thereline.
E the times hsted in these sectmas are not exact and typically may differ from the actual analytical pratiction by 1100 seconds O
Table A-4.18a g
MAAP4 Analyses Supporting SGTR Success Criterion ADS ceR E
Caw Equipment Assumptions g
Mas g
{
Tp ADS Core c
maap Temp a
run type i
2/3 4
M CMT ACC PRIIR NRilR IRWST Sensitivity Definition
(*19 g
[
gl5 baseline 3
I Yes I kne SGTR, no see isol, em Cl no urma T3 as gl5a support 1
1 Yes Iline SGTR no sec isol, no CI no um..
7.
3 gl5b support 3
I Yes I hoe SGTR. no sec isol no uncov m
c 2
gl5c support 3
I Yes I line SGTR. no see isol no uncov 3
u O
- I.
iir U'
Table A-4.18b SEQUENCE OF EVENTS '/OR SGTR SUCCESS CRITERION ADS MAAP4 ANALYSES Cwr Int ction senet of Iwatt.n Accum. Inj (we)
(sec)
Opening of ADS Valves (wc)
(sec)
- Core Uncovery
- g pe.k Start hike Water IAvel(%)
Temp Caw Start Er.pty Start Depty 1
2 3
4 NRHR IRWST twc) at Thne (sec)
("F) 35 100 10090 9006 9126 10701 1
gl5s 100 18330 10757 11738 gl5h 100 10180 9049 9169 10722 gl5e 100 11130 10770 11527 N
l 3
2 Tunes for the start of NRilR. lRWST cose uncovery and minimum water level are from M AAP4 output that does not capture output at every tunestep. Therenne, g
the times listed in these sections are not exact and typically may differ from the actual analytical prediction by i!00 sectwals
E l
0 ts Table A-4.19a MAAP4 Analyses Supporting Transient Success Criterion ADA m
Caw Equipment Assumptiems ADS Core masp Temp run type 1
2/3 4
M CMT ACC PRHR NRifR 1RWST Sensitivity Definition
(*I.')
t5t t*aselme 3
I I kne Trans. no CI 1262 g
17al support 1
1 1
I hne Trans. no Cl 1194 t7a2 support 1
1 1
I hne Trans. No C1 1252
)
I Table A-4.19b SEQUENCE OF EVEN13 FOR TRANSIENT SUCCESS CRITERION ADA MAAP4 ANAI,YSES w
CMT isdection Start of lede tien Acewm Ird(we)
(seep Opening et ADS Valves (sec)
(sec)
- Care thovery
- e Peah Stan hen Water level (%)
Temir Case Start rapty start Empty I
2 3
4 NRiiR IRWST (sec) as Time (sec)
(T)
EG g
t5:
4847 9774 9057 9177 I'v113 9272 50% e 10080 1262 i71 4847 9773 9177 9387 10028 9272 52% e 10080 1894 g
47a2 4847 9984 8937 9773 107".J 10180 50 % @ 10600 I25l
[
1I 12 4
=
a E
3*
s O
S, 3-c t-X g
Tunes for the start of NRHR. IRWST core uncovery and minunum water level are from MAAP4 output that does not capture output at every tunestep. Therefore.
2 W
the times hsted m these secuans are tw* exact and typically may differ from the actual analytical predstmn by 2l00 secmds O
- S Table A-4.20a
- e E
MAAP4 Analyses Supporting MLOCA Success Criterion ADQ
(
s-en Case I;quipment Assumptions E
'-t Max w
E ADS Core 2
g mesp Temp l
run type 1
2/3 4
M CMT ACC 1*RIIR NRilR IRWST Sensithity ILfinitlan
(*F) o to l
m6e5 baselme 2
M i
1 Iline 8.75" hot leg ADS @ 30 inin, no Cl 1554 4
m6e6 suppwt 2
M i
I I kne 8.75* hot leg, ADS w 15 min, no Cl nn uncov m6e supewt 2
M i
1 I kne
$* hot leg. ADS @ 30 mm. no Cl 740 y
m6e2 suppwt 2
M 1
I Iline 5" coki leg. ADS w 30 min, no Cl no unco,
m6e4 suppwt 2
M I
1 I hne 5" hot leg, ADS w 15 nun, no CI am imcov c
3.
m6e8 suppwt 2
M i
1 I Ime 8.75* hot leg, ADS w 25 min, no Cl 1199 g
I m6e5a sens 2
M 1
1 I line 8.75* hot leg ADS W 30, no CI, min 1540 y
accm flow
=
m6e5b sens 2
M 1
1 I hne 8.75 h<w leg, ADS w 30, no CI, min 1556 grav inj Table A-4.20b SEQUENCE OF EVENTS FOR MLOCA SUCCESS CRITERION ADQ MAAP4 ANAL YSES CMT Brq)ntion 5 tart et lidwilen Actim. Inj (su)
(m)
Opening of AI. Valves (see)
(sec)
- Core thwevery *
)
l reas Start Min Water level Temp i
Caw Start Empty Start Fmpty 1
2 3
4 NRilR 1RWST (sec)
(%) at Time (sec)
(*F)
I m6es 100 682 1802 1803 1822 40 % # 1738 1554 m6e6 100 682 902 969 m6e 412 1930 18tl 2053 1134 86% e 1740 740 mne2 407 1937 1806 2111 m6e4 412 1974 911 1266
.N m6e8 100 682 1502 1510 1122 56% e 1527 1899 m6e5a 100 601 1802 1803 1119 41% e 1735 1540 tsi m6e5h 100 682 1802 1803 1822 40% e 1738 1556 Times for the start of NRilR, IRWST cme uncovery and nununum water level are from MAAP4 output that does ret capture otsput at every tunestep. Therefore, the times hsted in these sections we not exact and typically may differ ftom the actual analytical prediction by 1100 seconds m
___m
r I
c w
f Table A4.21a g
MAAP4 Analyses Supporting NLOCA Success Criterion ADQ Caw Equipment Assumptions ADS Core masp Temp run type 1
2/3 4
M CMT ACC PRilR NRilR 1RWST Sensittiity Definitinus
(*F) x4g baselme 2
M I
I kne 4.75" hot leg. ADS @ 30 man. no Cl
%9 x4g2 suppwt 2
M 1
I kne 4 75" hot leg. ADS # 15 mm. no Cl in uncow p
x4e4 support 2
M I
I kne 2" hot leg. ADS @ 15 nun, no CI no uncov x4f2 suppwt 2
M 1
I hne 2* hot leg. ADS @ 30 min nu uncow x4d suppwt 1
M 1
I kne 2* hot leg. ADS @ 30 min 714 x4J2 support 1
M 1
I hoe 2* hot leg. ADS @ 15 rmn 1058 D
C' CD Table A-4.21b SEQUENCE OF EVENTS FOR NLOCA SUCCESS CRITERION ADQ MAAP4 ANALYSES g
cur wuo stan.f w woe.
s Aconn. Inj (see)
(sect Opening of ADS Valves (su)
(sed
- Ceee Unmery
- T l
Peek Start Min Waner level (%)
Temp g
Caw Stan Empty Start Empsy 1
2 3
4 NRHR IRWST (sect at Thee (sw)
(T) y a4s 516 1946 1812 2082 925 82 % # 1539
%9 n4 2 516 1085 912 1293 nee 4 1028 1882 973 2359 n4f2 1943 20 %
1875 3920 n4d 1943 2163 1875 3920 3803 82 % @ 3905 715 M
ned2 1117 1343 975 2990 2775 70% W 2982 105s 5
e t
O E
c Times for the start of NRilR. IRWST core uucovery and minunum water level are from MAAP4 output that does not capture output at every tunestep. Therefiwe.
h the times listed in these sections are not exact and typically may differ from the actual analytscal predwtson by 2l00 seconds b
Table A-4.22a g
co MAAP4 Analyses Supporting SLOCA Success Criterion ADT 2
C-r.
Equipment Assumptions k
Max E
g c3 ADS Core y
C masp Temp 3
run type 1
2/3 4
M CMT ACC PRilR NRilR IRWST Sensitivity Definition
(*F) oy s6a4 baselme 2
M I
I kne 0.5* coM leg. ADS @ 15 min. no Cl no uncow
'o g
s6a3 support 2
M 1
1 ime 0.5* cold leg. ADS @ 30 min, no CI no uncow
]
7 s6al support 1
M 1
I hoe 0.5* coM leg. ADS @ 30 min, no CI 1867
[
h s6 2 support 1
M I
I hne 1.75* cold leg. ADS @ 30 min, no 1700 Cl Q=
(")
3.X S'
Table A-4.22b SEQUENCE OF EVENTS FOR SLOCA SUCCESS CRITERION ADT MAAP4 ANALYSES CMT ledection Start of Iqjectica Accuen. Inj (sec)
(sec)
Opening of ADS Valves (sec)
(sec)
- Care Uncovery
- Peak Start Min Water 14 vel (%)
Teiny Caw Start Empty Start Enipty 1
2 3
4 NRitR 1RWST (sec) at ilme (sec)
(*l')
s6a4 1828 1966 1730 3409 s6a3 2767 2858 2630 3769 s6al 2767 3043 2630 6401 5769 47% e 6377 1867 s6a2 1967 2187
-1857 5256 4538 52 % @ 5202 1700 i
S I
Tunes for the start of NRHR. IRWST core uncovery and minimum water level are from MAAP4 output that does not capture output at every timestep. Therefore.
t#5 the times hsted in these sections are not exact and typically may differ from the actual analytical predictkm by *100 seconds
E l
4' u
TableA-4.23a h
MAAP4 Analyses Supporting SLOCA Success Criterion ADT t
tes Caw Equipment Assumptions ADS Core masp Temp run type 1
2/3 4
M CMT ACC PRIIR NRIIR IRWST Sensithity Definition CF) sRa4 basehne 2
M I
Yes I hoe 0.5 coM leg. ADS @ 15. no CI n2 uncow s8a1 suppxt 2
M I
Yes I line 0.5 cokileg. ADS @ 30, no Cl zu uncov s8al support 1
M 1
Yes I kne 0.5 coM leg. ADS @ 30, no CI 1539 san 2 support I
M I
Yes I boe 1.75 cold leg. ADS @ 30. no CI 1362 w
l o
Table A-4.23b SEQUENCE OF EVENTS FOR SLOCA SUCCESS CRITERION ADT MAAP4 ANALYSES E
carr irono.o stan or isoeason Accues. Irq (sec)
(sec)
Opening er ADS Valves (sec)
(sa)*
Care Uncovery
- h 5
Pesit start Mm Waser Level (%)
Teasp
[
Case Start Empty Start Empty 1
2 3
4 NRilR I2wsT (sed as Thee (sec)
(*F) ma v_
38 4 1837 1%9 1730 3460 m
sta3 2463 2869 2630 3867 6
stat 2463 3024 2630 6428 5795 48% # 6408 1839 Y
m sta2 205 1201 1805
~438 3t57 65 % # 3464 1126 cn I
E a
n D
m g-$
h e
if l
g Tunes for the stait of NRilR,IRWST core uncovery and minimum water level are from MAAP4 output that does not capture output at every tunestep. Derefore.
3.
the times hsted in these sections are not exact and typically may differ from the actual analytral prahction by t!00 wcuimis e
I
Table A-4.24a g
g co MAAP4 Analyses Supporting SGTR Success Criterion ADT 4
B E
Case Equipment Assumptions Mas og g
}
Con o
AD Temp C
niaap run type 1
2/3 4
M CMT ACC PRIIR NRHR IRWST Sensitivity Definition
(*F) g y
g16 baseltne 2
M 1
I line SGTR, ADS @ 15 min, no CI no uncov T
]
'gg g16a support 2
M 1
Iline SGTR, ADS @ 30 min, no Cl no uncow 3
E n
3w O
3.X h
M*
Table A-4.24b SEQUENCE OF EVENTS FOR SGTR SUCCESS CRITERION ADT MAAP4 ANALYSES CMT Iedecties Start et injection Acnna. Iq) (sec)
(sec)
Opening of ADS Valves (sec)
(sec)
- Core Uncovery
- Peak Start Min Water 14 vel (%)
Temp Case Start Empty Start Empty 1
2 3
4 NRHR IRWST (sec) at lime (sec)
(*F) g16 1123 1254 1015 1351 g16a 2042 2125 1915 2356 l
3 4
l 2
~
Times for the start of NRHR. IRWST core uncovery and minimum water level are from MAAP4 output that does not capture output at every tunestep. Therefo.
8 the times listed in these sections are not exact and typically may differ from the actual analytical prediction by 2l00 seconds
==
3:
l I
N w
f Table A-4.25a MAAP4 Analyses Supporting SGTR Success Criterion ADT
'A Case Equipment Assumptions ADS Cove maap Temp run type 1
2/3 4
M CMT ACC PRIIR NRIIR IRWST Sensitivity Definition
(*F) gl7 baselme 2
M I
Yes I hoe SGTR ADS @ 15 no sec isol, no Cl no uncov st7a support 2
M 1
Yes I line SGTR, ADS @ 30, no sec isol. no CI nn uncow l
U Table A-4.25b SEQUENCE OF EVENTS FOR SGTR SUCCESS CRITERION ADT MAAP4 ANALYSES E
Chff injection Start of injection Acama. Inj (sec)
(sec)
Opening of ADS Valves (sec)
(sec)
- Core Unmeery
- g Peak Start h Water level (%)
Temp k
Cane Start Eanpey Start Empty 1
2 3
4 NRHR IRWST tsec) et he (sul
(*F) v 317 511 1232 1000 2611
{
gl7a 515 2093 1899 2581 o
m 14 1
r
<=
n E_
O m
oC X
Times for the start of NRHR, IRWST core uncovery and minunum water level are from MAAP4 output that does not capture output at every timestep. Therefore, 2.
the times hsted in these sections are not exact and typically may differ from the actual analytical predktion by 1100 seconds 1
P Y
Table A-4.26a I
MAAP4 Analyses Supporting Transient Success Criterion ADT 2
R n;-
Caw Equipment Ansvenptions g
9 ADS Core
[
E masp Temp 3
g run type 1
2/3 4
M CMT ACC PRHR NRHR IRWST Sensitivity Definition
(*F) g
[
t9a3 leaseline 2
M I
Iline Trans, ADS @ 15, no Cl no uncow
'o 3,
19al surport 1
M I
I kne Trans ADS @ 15, no Cl
> 2200 as 19a2 support 1
M 1
I hoe Trans, ADS @ 30, no Cl IR72 c
R 3
n "I
X 5
s d
Table A-4.26b SEQUENCE OF EVENTS FOR TRANSIENT SUCCESS CRITERION ADT MAAP4 ANALYSES CMT Injection Staat of laketten Actuva. ImJ (m)
(see)
Opening of ADS Valves (see)
(sec)
- Core Uncewry
- Start Mir Water level (%)
Tenop Cane Start Depay Start Empty 1
2 3
4 NRIIR 1RWST (sec) at Dee (sec)
(*F) t9a3 1023 1895 960 2520 t9 1 1828 1425 960 4592 3913 44 % 's 4625
>2200 m
t9a2 2053 2293 1860 568I 5016 505 e 5628 1872 5
4 l
.M M
Tunes for the start of NRHR. IRWST core uncovery and minimum water level are from MAAP4 output that does exd capture outret at every tunestep. Therefore, tsi the times listeal in these sections are not exact and typically may differ from the actual analytical prediction by 2l00 seconds
l 4
Table A4.27a h
MAAP4 Analyses Supporting ADS Manual Action Delay Time from Low-l CMT Level (Auto Failed) us Case Equipment Assumptions Core ADS masp Succ.
Temp rue Crit i
2/3 4
M CMT ACC PRilR NRIIR IRWST Sensitivity Definition
('F) h xtbopt ADU 2
M 1
1 2* cold leg. ADS @ 30 1147 sl6kopt ADIA 2
M 1
1 0.5* hot leg. ADS @ 30 1565 M
1 Yes 1
0.5" cold leg. ADS @ 30 no uncov sloop!
ADV 1
310eg l ADIA 2
M 1
1 SG1R. ADS @ 30 1542 gliopt ADV 1
M i
Yes 1
SGTR. no sec isol. ADS @ 30 no uncow tiopt ADIA 2
M i
1 Trar s ADS @ 30 1109 m3 4 cpl ADM 2
M 1
1
$* cold leg. no C1. ADS @ 30 no uncov D
m3d4 cpl ADM 2
M 1
1 2* hot leg. no Cl. ADS @ 30 no uncov sit 2 opt ADA 3
M 1
1 1.75* cold leg. no CI, ADS @ 30
>2200 s4 opt ADS 3
M 1
Yes 1
1.75 cold leg. no C1. ADS @ 30 1520
?
gl4eg 1 ADAG 1
1 M
1 1
SG1R. no C1. ADS @ 30 1594 3>
ll 315 cpl ADS 3
M 1
Yes 1
t5 top!
ADA 3
M 1
I Trans. no CI. ADS @ 30 1047 p
ec-s l
2 E,,
nN
=r lll 9
0 e
a-N 3..
b
D g
Table A-4-27b 4
SEQUENCE OF EVENTS FOR ADS DELAY MAAP4 ANALYSES 5
CMT Injectlen seert of fedection E
Accean. Inj (sec) teec)
Opening of ADS Valm (see)
(sec)
- Core IJacovery
- N" N
Fesk g
Start Min Water Lewt Temp g
Csee guart Empty Start Empty 1
2 3
4 NRHR IRWST (see)
(%) at Thne (see)
(*F) c
'O altmps 51 3262 1851 4796 4266 53% @ 4772 1147 33 sl6kopf 1290 4976 3090 6693 5883 37 % @ 6689 1565 m
c sloopi 830 6526 2630 4022 Q
3 gloecpl 116 3682 1916 7574 6699 36 % @ 7603 1542 m
O gligt 100 5705 1400 2611 g.
tiept 4698 8250 6498 9934 9286 52% @ 9997 1109 m3g491 7
1843 1906 2441 13d4 cpl 73 3361 1873 3131 NW sit 2 cpl 57 2858 1857 1857 4902 3752 14 % @ 8160
>2200 e zept 100 3475 1900 1900 5045 4476 60% @ $077 1520 c
gl4e91 116 3472 1916 1916 34n 3572 18 % @ 3572 1594 I
sis,I 10 0 3534 1900 1900 5301
,5137 85% @ 5337 663 15eopt 4847 7936 6647 6647 9204 9204 76 % @ 9245 1047 Times for the start of NRIIR. IRWST core amicovery and minimum water level are from MAAP4 output that does not capture output at every timestep. Therefore, the times listed in these sections are not exact and typically may difier from the actual analytical prediction by 1100 seconds
=n l
u W
vt
E I
a
.?
u Table A-4.28a MAAP4 Analyses Supporting CMT Manual Action Delay Time from CMT Signal (Auto Failed)
Caw Equipment Asemptices y
ADS Core masp Succ.
Temp run Crit 1
2/3 4
M CMT ACC PRilR NRIIR 1RWST Sensitiitty Definition
(*F) y h
albop2 ADU 2
1 1
2* coki leg, CMT @ 10 1828 sl6kop2 ADIA 2
1 1
0.5* hot leg CMT @ 20 1269 sloop 2 ADV 1
1 Yes 1
0.5* coki leg. CMT @ 20 nu uncov 310aop2 ADIA 2
1 1
SGTR, CMT @ 30 1098 gliop2 ADV I
I Yes 1
SGTR, no sec isol, CMT @ 30 no uncow tiop2 ADIA 2
1 I
Trans, CMT@ 30 1026 M
m3g40p2 ADM 2
I 1
5* cokileg, no CI. CMT @ 10 no uncov x3ddop2 ADM 2
1 1
2* hot leg, no Cl. CMT # 10 846 sit 20p2 ADA 3
I 1
1.75* cold leg, no Cl, CMT @ 20 1622 9
s4 rop 2 ADS 3
1 Yes 1
1.75 cold leg. no Cl. CMT @ 20 1314 6
gl4eop2 ADAG 1
I I
I SGTR no Cl, CMT @ 30
>2200 v"'"
gl5op2 ADS 3
1 Yes 1
SGTR. no Cl, CMT @ 30 notawov Mw t5 top 2 ADA 3
1 l
l Trans, no CI, CMT @ 30 124I E
rn lI T2
-e:
E k-g U
Q 5-D Q
8 EF i
4
o E>>
O f
E Table A-4.28b 47 SEQUENCE OF EVENTS FOR CMT DELAY MAAP4 ANALYSES 3
o cwr i.oeas.n st.n er i.9eason Anatn. led (m)
(see tW of ADS Valves (m)
(m)
- Core Uncovery *
[
- ts g
Peelt 3
Start Man Water level Tenip 3
Case Start Fsyty Start Empty 1
2 3
4 NRitR IRW57 (m)
(%) et linie (m)
(*F) p altg2 651 3274 2203 4796 4282 53 % 8 4758 1828 sl6k m2 2490 14610 13711 15276 14200 32 % @ 15310 1269 sl0np2 2029 43798 44496
.f, g10eg2 1915 14000 12927 16698 16020 50% e 16720 1098 F
f all,2 1899 2737 11, 2 6498 8063 6960 9992 5828 33% e 6437 1026 y
N m34,2 607 2260 1681 2473 m3d40p2 673 3412 3499 3796 3613 53% e 3814 0,;
sit 2g2 1257 3784 2829 2949 5359 4737 55% e 5388 1623 s4 op2 1300 5307 4025 4146 6737 620s 66% e 6809 1334 gl4eg2 1315 13820 13040 13329 18376 16:30 0% e 22240
>2200 als,2 1300 im 8922 9042 10769 l
t5op2 6647 8156 7229 7349 9897 5727 22% e e647 1241
- Times for the start of NRHR,IRWST core uncovery and minimum water level are from MAAP4 output that does not capture outpel at every tirnestep. Therefore, the times listed in these sections are not exact amt typically may differ from the actual samlytical prediction by 2100 seconds 34 l
5 ut g
3 l
t 4
l y
l 8
os i
Table A-4.29a MAAP4 Analyses Supporting PRilR Manual Action Delay Time from PRIIR Signal (Auto Failed) l Caw Equipment Assumptions Mu Core mesp Secc.
Temp h
ADS run Crit i
2/3 4
M CMT ACC PRIIR NRHR 1RWST Sensitivity Definition CF) p s100p3 ADU l
I Yes 1
0.5" cokileg, PRHR @ 30 no uncov Silop3 ADIA 1
1 Yes 1
SGTR. no sec isol, PRGR @ 30 no uncov s4 rop 3 ADV 3
I Yes 1
1.75* coki leg, no Cl, PRilR @ 30 1043 m
glSop3 ADIA 3
1 Yes I
SGTR,no sec isol, no Cl, no uncov PRHR @ 30 D
u O
7" Table A-4.29b b
SEQUENCE OF EVENTS FOR PRilR DELAY MAAP4 ANAI,YSES 2
CMT Inbetice Start of injecuen y
Accum, laj (sec)
(sec)
Opening of AIM Valves (sec)
(sec)
- Core Uncovery
- g M
Start Min Water 14*el Temp 3
Cee Start Fmpty Start Empty 1
2 3
4 NRHR IRWST (sec)
(%) st11me (sec)
(*F) g s10np3 830 38010 35889 37451
[
'O 311 93 100 3274 32 s4mp 100 4183 3285 3405 5615 5385 79% e 5686 1040 m
e R
815,
100 7900 6883 7003 8435 R
T Tunes for the start of NRHR, IRWST core uncovery and minimum water level are from MAAP4 output that does not capure output at every tunestep. Therefore.
the tunes Ested in these sections are not exact and typically may differ from the actual analytical prediction by 100 seconds s
a
l Table A430a y
MAAP4 Analyses Supporting RNS Manual Action Delay Time from Break Initiation (Auto Failed)
K Caw Equipment Azumptions Core
]
ADS g
tunsp Succ.
Temp y
nin Crit 1
2/3 4
M CMT ACC PRHR NRHR 1RWST Sensitivity Definition
(*F) g g
E m2c2 ADU 1
1 8.75* hot leg. NRHR @ 30 1353 n
1 I
8.75* hot leg, NRHR @ 20 558 g
m2c3 ADIA te 4
m2c ADV 1
1 8.75* cold leg no uncov m2b ADIA 1
1 5" hot leg (note 1) 880 ll l
m2 AIW 1
1 5" cold leg (note 1) 671 y
R l
ml ADIA 1
1 5" cold leg (note 1) no uncov g
a mia ADM 1
1 5* hot leg (note 1) 688 O
E Note: 1 - NRHR cannot inject until after 30 minutes.
Table A-4.30b to SEQUENCE OF EVENTS FOR RNS DELAY MAAP4 ANALYSES CMT Injection Start et lajection Actum. In)(sec)
(see)
Opentag of ADS Valves (sec)
(sec)
- Core Uncovery
- reak Start Min Watee 1svel Temp Case Start Empty Start Empty 1
2 3
4 NRilR IRWST (see)
(%) at 'Ilme (sec)
(*F) m2c2 101 686 1800 1520 67 % @ 1425 1353 m2c3 101 686 1200 1120 91% e 1120 558 m2e 101 749 359 m2b 410 2468 1993 1130 85 % @ 1947 880 g
m2 406 2953 2631 2259 90 % @ 2560 671 m
ml 7
1858 3860 l
J"*
mia 11 2048 4045 3393 48 % @ 4012 1264 h
Tunes for the start of NRHR. IRWST ane uncovery and minimum water level are from MAAP4 output that does not capture outgut at every tunestep. Herefore, the times listed in these sections are not exact and typically may differ from the actual analytical predstion by s100 seconds tn
~
DRAFT
.. miAP, inaiy,es to Szpport Success Criteria i
Table A-5 SLOCA CASES FOR ADS MANUAL ACTUATION (NRHR OPERATION)
ADS Liner Manually Case Operator Action Time CMT Actuation Signal Opened S19b 15 minutes 830 seconds 1730 seconds S19d 120 minutes 830 seconds 8030 seconds S19g 210 minutes 830 seconds 13430 seconds 4
Table A-6 AUTOMATIC ADS SUCCESS CRITERIA FOR IRWST GRAVITY DRAIN, NO PRIIR Success Criteria MAAP4 Peak Core Success Criteria Case Definition MAAP4 Case Temperature (*F)
ADM 2/4 stage 4 MLOCA, m3n No Core Uncovery NLOCA, x3b3 779 ADAB, ADAL, ADA 3/4 stage 2,3 SLOCA, s1 1108 OR 1/6 stage 1,2,3 and 1/4 SGTR. g4 1335 stage 4 Transient, t5 1158 Table A-7 TRANSIENT CASES FOR ADS MANUAL ACTUATION (IRWST GRAVITY DRAIN)
Operator Action PRIIR Actuation ADS Lines Manually Case Time Signal Opened T9a 30 minutes 60 seconds 1860 seconds T9b 90 minutes 60 seconds 5460 seconds T9d 150 minutes 60 seconds 9060 secotxis WestinghDlJSB A.
80 W-
i DRAFT
~
A. MAAP4 Analyses to S:pport Success Criteria Table A-8 NLOCA CASES FOR ADS MANUAL ACTUATION (IRWST GRAVITY DRAIN)
ADS Lines Manually Case Operator Action Time CMT Actuation Signal Opened X4d2 15 minutes 75 seconds 975 seconds X4d4 60 minutes 75 seconds 3675 seconds Table A-9 APPROXIMATE TIMES TIIAT NRHR IS CREDITED IN MAAP4 ANALYSES Time of NRHR Operation, After.
PRHR Actuation CMT Actuation Initiating Esent Esent Initiation Signal Signal ADS Actuation NLOCA 40 minutes 40 minutes 40 minutes 20 minutes SLOCA 85 minutes 85 minutes 85 minutes 25 minutes SGTR 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> 2 hours 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> 30 minutes Transient 3 houn 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> 90 minutes 25 minutes W Westinghouse A.
81
~
~
DRAFT A. MA.AP4 Analyses to Support Success Criteria Define Success Configuration ir Define Baseline Case i
Run MAAP4 Redefine Tp < 2200 F Success Configuration I
ll I'
Success Criteria Tp >1000 K Defined i
Yes 1
Perform Sensitivity Studies i
Run MAAP4 l
Tp > 2200 F
/
Yes Figure A-1 Process for Justification of Success Criteria Defined With MAAP4 Analyses May 31,1995 gg-W Mn@un A-82 W,h
DRAFT a
A. MAAP4 Analyses to Srpport Success Criteria i
CMT Bolence une n
DVI Une and CMT Unos are 8 inch Pipe CMT 8 isolation Volve CWT injection Une Cold Leg 2 Check Volves 4.0 in. Flow Restrictor 2
W RHR
=
DVI Une Downcomer 3.7 in. Flow Restrictor Figure A-2 Diagram of CMT and DVI Lines W westinghouse E
A-83