ML12292A404
| ML12292A404 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 10/17/2012 |
| From: | Ameren Missouri |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML122920434 | List: |
| References | |
| Download: ML12292A404 (34) | |
Text
ULNRC-05919 October 17, 2012 Page 1 of 34 CALLAWAY PLANT UNIT 1 LICENSE RENEWAL APPLICATION REQUEST FOR ADDITIONAL INFORMATION (RAI) RESPONSE TO ITEMS 5D, 7A, 7B, TABLES 7-1, 8-1, 9-1, AND 11-1
ULNRC-05919 October 17, 2012 Page 2 of 34 RAI 5.d:
Note 1 to Table F.3-2 states, "The current plant procedures and training meet current industry standards. There are no additional specific procedure improvements that could be identified that would affect the result of the human error probability (HEP) calculations. Therefore, no SAMA items were added to the plant specific list of SAMAs as a result of the human actions on the list of basic events with RRW greater than 1.005." This appears to imply that meeting current industry standards is sufficient to indicate that no additional SAMAs are needed.
- i. Provide additional information to justify the conclusion stated as indicated above.
ii. Explain the process used to make the determination that there are no opportunities to improve procedures and training. Include in the explanation how human error probability factors were considered (e.g., cognition, resources, timing, and stress level).
iii. Discuss whether any of the risk significant operator action failures could be addressed by options other than training or procedures such as automated functions, testing, and maintenance to reduce failure or event rates, or enhanced documentation. Specifically discuss the potential for automating the function associated with basic event OP-XHE-FO-CCWRHX (OPERATOR FAILS TO INITIATE CCW FLOW TO THE RHR HXS) identified in Table 3-2.
Callaway Response In order to perform a cost/benefit analysis of any change, the impact on the calculated Human Error Probability must be determined. Discussion with the HRA analysts indicate that based on the current structure and format of the existing procedures, any incremental improvements or changes made to training or procedures would not result in the ability to take additional credit in the HRA because in general full credit is already taken. Improvements may be possible through re-ordering steps in the EOP network to improve timing, however, since Callaway uses the standardized EOP network significant changes in EOP structure would result in compliance issues with EOP configuration control. The current standardized EOP structure is based on the deterministic safety analysis, not a PRA analysis, thus while there may be PRA improvements there are significant analysis and infrastructure changes that would have to be implemented Industry-wide to change the standardized structure. Any enhancements that could be made within the standardized structure have either already been made at Callaway or would not result in additional significant credit in the HEP determination. With no significant change to the HEP, the benefit of making the change would be negligible.
The note was not intended to state that no opportunities for improvement exist, rather that there would be no calculated dollar value benefit from any improvements made. Plant personnel are always encouraged to use the corrective action process to identify potential improvements. In addition, the PRA group reviews and actively participates in changes made to Operating Procedures to evaluate impact on the PRA as well as suggest improvements.
ULNRC-05919 October 17, 2012 Page 3 of 34 In general, operator actions credited in the Level 1 PRA, are proceduralized in the EOP and OTO procedure network. The EOP/OTO procedures address both cognition and execution as follows:
x Cognition - specifically they identify the primary cue (instrumentation or alarm needed to make the diagnosis) x Execution - specifically they identify the tasks needed to accomplish the required action).
The EOP/OTO procedures are highly trained on both in the classroom and to the extent possible in the simulator or through job performance measures. All EOPs are required to be trained on at least once every six years. In general, most EOPS are trained on several times a year in both the simulator and class room training. There is a six week training cycle and each crew will spend one week in simulator and/or class room training during each six week cycle.
The trainers review the procedures regularly to identify areas where the training crews have encountered difficulty and update the procedures accordingly. EOP/OTO Writers manual APA-ZZ-00102 is the guidance document the procedure writers follow to ensure that the procedures are written to be consistent with industry standards.
As part of the HRA task the EOP and OTO procedures are reviewed to ensure that credited operator actions in the PRA are proceduralized in the same context as the EOPS/OTOs. The HRA task accounts for the following:
x Procedure Context -Does the procedure match the modeled PRA scenario, x
Procedure Structure - Response not obtained column format vs. paragraphs of instructions, x
Procedure Wording - Does the procedure wording have a double negative, x
Distinction of important steps (boxed, bulleted, bolded, etc),
x Time to reach the required procedure step.
If the HEP is dominated by a single failure mechanism such as an ambiguously worded statement or not enough time to reach the required procedure step, then these findings are passed back to the Callaway training department and procedure revisions are made within the limitations of standardized procedures, as applicable.
The Callaway training department maintains a listing of time critical deterministic and PRA risk significant actions in procedure APA-ZZ-00395. On a defined cycle, the deterministic operator actions are evaluated/validated in the simulator, including timing of events. There is considerable overlap in the deterministic operator actions and the PRA risk significant actions and timing information from these validations is used to evaluate the assumptions in the HRA.
This training identifies procedure ambiguities associated with the procedure guidance for most actions credited in the PRA. These completions times are not requirements but are intended to be nominal average estimates that most crews can achieve. Following the completion of a major PRA update APA-ZZ-00395 is updated.
As part of PRA Update 5, all Level 1 post-initiator operator actions were reviewed and updated to align with the current EOP/OTO procedure revisions and training. As part of this update, all
ULNRC-05919 October 17, 2012 Page 4 of 34 risk-significant scenarios were talked through with Callaway trainers and insights from recent simulator training were incorporated into the updated HRA.
The process followed for this HRA update was:
- 1. Identify - Each PRA scenario was reviewed in the context of the appropriate EOP to ensure that the as-operated plant is reflected in the HRA.
- 2. Define - As part of the definition a feasibility check was performed for each HFE. This included defining both a cognitive and execution procedure, identify the frequency and level of training, showing there is enough time to complete the action, and there are enough people available to perform all tasks associated with the initiating event.
- 3. Quantify - The HEP is quantified using the EPRI HRA approach which accounts for a combination of cognitive and execution performance shaping factors.
- 4. Uncertainty - The uncertainty is addressed both qualitatively and quantitatively in the HRA.
As part of the HRA update no procedure updates to improve the SAMA were identified.
A case was quantified to determine the benefit of automating the initiation of CCW flow to the RHR heat exchangers. This case was evaluated by setting the value of basic event OP-XHE-FO-CCWRHX to 0.0. The benefit of this modification was determined to be $62K with the 95% CDF benefit being $132K. This modification was judged to be not cost beneficial be potentially cost-beneficial with an estimated cost of $200K.
The cost of adding hardware systems to automatically perform the actions represented by important human actions is high. This cost has been shown in a number of SAMA submittals to sometimes be order(s) of magnitude higher than the benefit achieved.
Other non-procedural changes such as additional maintenance and testing would not necessarily reduce risk significant human errors. Most equipment related failures are induced by human errors during testing or maintenance. The benefits of increasing the occurrence of tests and maintenance diminish at the point where additional maintenance or restoration errors are introduced or at the point where undue wear and tear occurs. Callaway's maintenance and testing program uses vendor recommended test and maintenance intervals as well as operating experience in an attempt to optimize mechanical reliability. Randomly increasing test and maintenance over the recommended intervals is perceived to have no mechanical reliability benefit; but would pose an increase in maintenance and restoration errors as well as wear and tear.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.
ULNRC-05919 October 17, 2012 Page 5 of 34 RAI 7.a:
A note at the end of Table F.5-1 indicates that recent industry submittals of like-kind plants (i.e.,
Wolf Creek, South Texas, Diablo Canyon, and Seabrook) were used as a source of candidate SAMAs. The extent to which these submittals were examined is not clear, as only two SAMA candidates were identified in Table F.5-1 as being from these sources (I.e., SAMA 162 and 165). Also, it appears that a cost beneficial SAMA identified in the Diablo Canyon submittal might represent an unevaluated SAMA candidate for Callaway (Le., SAMA 24 -Prevent clearing of RCS cold leg water seals). Describe the extent to which the four cited SAMA submittals were used as sources to generate candidate SAMAs and evaluate each SAMA determined to be cost beneficial in those submittals or show how they could be screened out using criteria presented in ER Section F.6.0. If the SAMA review for a submittal has been completed, use the cost beneficial SAMAs as reported in the respective site specific volume of NUREG-1437, "Generic Environmental Impact Statement for License Renewal of Nuclear Plants."
Callaway Response This entire 7.a response is provided by this transmittal and was not part of Reference 3.
The SAMA section of the Environmental Report for each of the listed submittals was reviewed.
The site specific volume of NUREG-1437 was reviewed for those plants where one was available. For each SAMA item the descriptions and decisions of the cost/benefit analysis were reviewed for applicability and site specific cost/benefit to Callaway. The tables below show the Callaway disposition for each plant's potentially cost beneficial SAMAs.
Wolf Creek SAMA Description Callaway Disposition SAMA 2: Modify controls and operating procedures to permit the diesel generators at the Sharpe Station to be more rapidly aligned to the WCGS emergency buses in SBO events.
The Callaway AEPS design already maintains constant AC power up to the safety related/non-safety related separation breakers with the breaker controls located in the main control room. The AEPS diesel generators automatically start and supply AC power up to the separation breakers on loss of the normal supply; and, if required, the manual diesel controls are also located in the main control room.
SAMA 4: Proceduralize operator actions to perform local isolations of any valves that fail to close remotely in an interfacing system LOCA.
Callaway procedure ECA-1.2 contains direction for operators to manually close all valves in ISLOCA pathways that are located outside containment if the valves cannot be closed from the control room.
ULNRC-05919 October 17, 2012 Page 6 of 34 SAMA 5: Modify procedures to open emergency diesel generator room doors to provide alternate room cooling given failure of the heating ventilation and air-conditioning (HVAC) supply fan.
SAMA 80 has been modified to indicate that procedural guidance to open doors or provide alternate ventilation following loss of EDG HVAC is potentially cost beneficial.
SAMA 1: Install a permanent, dedicated generator for the NCP in order to provide RCP seal cooling in SBO events.
SAMA 187 has been added. AEPS was installed with a spare breaker that could be used to supply the NCP. This SAMA is considered potentially cost beneficial.
SAMA 3: Provide the capability to cross-tie between 4-kilovolts (kV) AC buses in the event of a loss of power to one bus.
This SAMA was evaluated using case 4KV2 and was determined to have a benefit of $13K with a 95% CDF benefit of $27K. Callaway SAMA 11 has been modified to consider this SAMA to be potentially cost beneficial. A physical cross-tie exists, but there is no analysis or procedures to allow its use except in specific conditions with offsite power available. Associated Costs are to develop procedures and analysis to allow use of the cross-tie with the Emergency Diesel Generators. The SAMA is already evaluated as potentially cost beneficial; however, it should be noted that the calculated benefit is somewhat under-estimated since it was evaluated only for SBO sequences.
SAMA 13: Install an alternative fuel oil tank with gravity feed capability to address fuel oil transfer failure events.
This SAMA is included as Callaway SAMA 162 and has been determined to be potentially cost beneficial.
SAMA 14: Install a permanent, dedicated generator for the NCP, and a motor-driven AFW pump and battery charger to address SBO events in which the TD AFW pump is unavailable.
SAMA 188 has been added. This SAMA was evaluated using case SBOMOD2 and was determined to have a benefit of $182K with a 95% CDF benefit of $385K. AEPS was installed with a spare breaker and expansion capability which could be used to supply various equipment. This SAMA is considered potentially cost beneficial.
Case SBOMOD This SAMA case was analyzed by multiplying the frequency of all SBO sequences by 1.0E-01 which represents the total failure probability of the operator errors and hardware failures associated with operation of the equipment that would be made available due to this modification.
No changes were made to support system modeling.
ULNRC-05919 October 17, 2012 Page 7 of 34 Case SBOMOD2 This SAMA case was analyzed by multiplying the frequency of all SBO sequences by 5.0E-02 which represents the total failure probability of the operator errors and hardware failures associated with operation of the equipment that would be made available due to this modification. No changes were made to support system modeling.
Case 4KV2 This SAMA case was analyzed by modifying the fault trees to include a cross-tie to the other 4KV AC bus and diesel generator. Only SBO sequences were solved and the results combined with the remainder of the baseline model results. The probability of failure for the cross-tie was assigned a probability of 5.0E-02. The cross-tie failure event was removed from cutsets containing the failures of both EDGs (including those caused by support equipment). No changes were made to support system modeling. The calculated benefit under-estimates the actual benefit since the benefit was only determined for SBO sequences. The benefit for other sequences could not be determined without extensive modifications to the PRA model.
The low benefit of this SAMA is attributed to the AEPS AC power supply that can be controlled from the main control room and the ability to have AEPS aligned to either 4KV bus and the ability to use the non-safety auxiliary feed pump.
Seabrook SAMA Description Callaway Disposition SAMA 157: Provide independent AC power source for battery chargers This item is considered implemented at Callaway. Procedures and equipment exist that will provide temporary portable power sources for the battery chargers.
SAMA 165: RWST fill from firewater during containment injectionModify 6 inch RWST flush flange to have a 21/2-inch female fire hose adapter with isolation valve This item is considered implemented at Callaway. Procedures and equipment exist to connect fire water to the RWST.
SAMA 192: Install a globe valve or flow limiting orifice upstream in the fire protection system This item is considered to be N/A for Callaway.
This is a plant specific internal flooding issue that was not identified for Callaway.
SAMA 193: Hardware change to eliminate MOV AC power dependency This item is considered to be N/A for Callaway.
This is a plant specific PRA importance issue that was not identified for Callaway.
ULNRC-05919 October 17, 2012 Page 8 of 34 South Texas Project South Texas Project has no potentially cost beneficial SAMA items.
Diablo Canyon SAMA Description Callaway Disposition SAMA 12: Improve Fire Barriers for ASW and CCW Equipment in the Cable Spreading Room This item is considered to be N/A for Callaway.
This is a plant specific fire related issue that was not identified for Callaway.
SAMA 13: Improve Cable Wrap for the PORVs in the Cable Spreading Room This item is considered to be N/A for Callaway.
This is a plant specific fire related issue that was not identified for Callaway.
SAMA 24: Prevent Clearing of RCS Cold Leg Water Seals This SAMA is included as Callaway SAMA 179 and has been determined to be potentially cost beneficial.
SAMA 25: Fill or Maintain Filled The Steam Generators to Scrub Fission Products This item is considered implemented at Callaway. The Emergency Operating Procedures contain direction to maintain steam generator level above the tubes.
Also refer to Tables 7-1, 8-1, 9-1, and 11-1 which directly follow this response.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.
ULNRC-05919 October 17, 2012 Page 9 of 34 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway SAMA Number Potential Improvement Discussion
% Red.
In CDF
% Red.
In OS Dose SAMA Case SAMA Case Description Benefit Cost
% Red IN OECR Cost Basis Evaluation Basis for Evaluation 1
Provide additional DC battery capacity.
Extended DC power availability during an SBO.
12.17% 10.87%
NOSBO No Station Blackout Events
$360K
>$1M 10.49%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
2 Replace lead-acid batteries with fuel cells.
Extended DC power availability during an SBO.
12.17% 10.87%
NOSBO No Station Blackout Events
$360K
>$1M 10.49%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
5 Provide DC bus cross-ties.
Improved availability of DC power system.
0.30%
0.00%
$1K
>$199K 0.03%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
11 Improve 4.16-kV bus cross-tie ability.
Increased availability of on-site AC power.
0.26%
0.58%
4kv2 Add 4KV cross-tie capability for SBO sequences
$13K
<$100K 0.58%
Expert Panel Potentially Cost-Beneficial Physical cross-tie exists, but there is no analysis or procedures to allow its use except in specific outage conditions. Cost is to develop procedures and analysis to allow use of the cross-tie. Benefit calculated is under-estimated since it was evaluated for only SBO sequences.
15 Install tornado protection on gas turbine generator.
Increased availability of on-site AC power.
2.65%
4.35%
LOSP1 No tornado related LOSP
$91K
>$500K 3.38%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
24 Bury off-site power lines.
Improved off-site power reliability during severe weather.
40.66% 41.30% NOLOSP Eliminate all Loss of Offsite Power Events
$1.2M
>$3M 35.28%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
Previous SAMA submittals have estimated approximately $1M per mile.
25 Install an independent active or passive high pressure injection system.
Improved prevention of core melt sequences.
2.77%
0.00%
LOCA12 No failures of the charging or SI pumps
$48K
>$1M 0.35%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
26 Provide an additional high pressure injection pump with independent diesel.
Reduced frequency of core melt from small LOCA and SBO sequences.
2.77%
0.00%
LOCA12 No failures of the charging or SI pumps
$48K
>$1M 0.35%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
28 Add a diverse low pressure injection system.
Improved injection capability.
3.19%
2.17%
LOCA03 No failure of low pressure injection
$65K
>$1M 1.01%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
29 Provide capability for alternate injection via diesel-driven fire pump.
Improved injection capability.
Potentially Cost-Beneficial SAMA is judged to be low cost, but analysis is needed to determine impacts of injection of non-borated water to RCS.
Expert Panel judged this SAMA to be potentially cost-beneficial without determining an actual benefit or cost.
ULNRC-05919 October 17, 2012 Page 10 of 34 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway SAMA Number Potential Improvement Discussion
% Red.
In CDF
% Red.
In OS Dose SAMA Case SAMA Case Description Benefit Cost
% Red IN OECR Cost Basis Evaluation Basis for Evaluation 39 Replace two of the four electric safety injection pumps with diesel-powered pumps.
Reduced common cause failure of the safety injection system. This SAMA was originally intended for the Westinghouse-CE System 80+, which has four trains of safety injection.
However, the intent of this SAMA is to provide diversity within the high-and l 2.77%
0.00%
LOCA12 No failures of the charging or SI pumps
$48K
>$1M 0.35%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
41 Create a reactor coolant depressurization system.
Allows low pressure emergency core cooling system injection in the event of small LOCA and high-pressure safety injection failure.
0.78%
0.00%
DEPRESS No failures of depressurization
$12K
>$500K 0.27%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
43 Add redundant DC control power for SW pumps.
Increased availability of SW.
0.30%
0.00%
SW01 Service Water Pumps not dependent on DC Power
$1K
>$100K 0.06%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
46 Add a service water pump.
Increased availability of cooling water.
17.60% 27.72%
SW02 No failures of ESW pumps
$636K
>$5M 23.26%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
54 Increase charging pump lube oil capacity.
Increased time before charging pump failure due to lube oil overheating in loss of cooling water sequences.
0.48%
0.00%
CHG01 Charging pumps not dependent on cooling water.
$4K
>$100K 0.06%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
55 Install an independent reactor coolant pump seal injection system, with dedicated diesel.
Reduced frequency of core damage from loss of component cooling water, service water, or station blackout.
5.54%
0.00%
$94K
>$1M 0.21%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
Previous investigation into installing such a system concluded that operators did not have sufficient time to place the system in service prior to seal damage.
56 Install an independent reactor coolant pump seal injection system, without dedicated diesel.
Reduced frequency of core damage from loss of component cooling water or service water, but not a station blackout.
5.54%
0.00%
$94K
>$500K 0.21%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
58 Install improved reactor coolant pump seals.
Reduced likelihood of reactor coolant pump seal LOCA.
5.54%
0.00%
$94K
>$3M 0.21%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
59 Install an additional component cooling water pump.
Reduced likelihood of loss of component cooling water leading to a reactor coolant pump seal LOCA.
3.61%
0.00%
CCW01 No failures of the CCW Pumps
$59K
>$1M 0.07%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
ULNRC-05919 October 17, 2012 Page 11 of 34 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway SAMA Number Potential Improvement Discussion
% Red.
In CDF
% Red.
In OS Dose SAMA Case SAMA Case Description Benefit Cost
% Red IN OECR Cost Basis Evaluation Basis for Evaluation 64 Implement procedure and hardware modifications to allow manual alignment of the fire water system to the component cooling water system, or install a component cooling water header cross-tie.
Improved ability to cool residual heat removal heat exchangers.
5.39%
0.76%
FWCCW 2
Evaluate fire water hookup to RHR HX
$104K
<$150K 0.77%%
Expert Panel Potentially Cost Beneficial The cost estimate is for development of a procedure and use of temporary connections.
Cost of permanent modification would be significantly higher.
65 Install a digital feed water upgrade.
Reduced chance of loss of main feed water following a plant trip.
1.57%
0.00%
FW01 No loss of Feedwater Events
$29K
$19M 0.49%
Callaway Modification Costs Not Cost-Beneficial Cost will exceed benefit.
71 Install a new condensate storage tank (auxiliary feedwater storage tank).
Increased availability of the auxiliary feedwater system.
1.14%
0.00%
CST01 CST does not deplete
$18K
>$2.5M 0.24%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
77 Provide a passive, secondary-side heat-rejection loop consisting of a condenser and heat sink.
Reduced potential for core damage due to loss-of-feedwater events.
1.57%
0.00%
FW01 No loss of Feedwater Events
$29K
$>1M 0.49%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
79 Replace existing pilot-operated relief valves with larger ones, such that only one is required for successful feed and bleed.
Increased probability of successful feed and bleed.
3.43%
2.17%
FB01 Only one PORV required for Feed &
Bleed
$79K
>$500K 1.68%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
80 Provide a redundant train or means of ventilation.
Increased availability of components dependent on room cooling.
6.08%
4.35%
$156K
<$100K 3.87%
Expert Panel Potentially Cost Beneficial Procedures to open doors or provide temporary ventilation may be cost beneficial for the EDGs, MDAFW pumps, and charging pumps.
Procedures for opening doors to the DC switchgear rooms exist.
87 Replace service and instrument air compressors with more reliable compressors which have self-contained air cooling by shaft driven fans.
Elimination of instrument air system dependence on service water cooling.
0.36%
0.00%
INSTAIR Eliminate all instrument air failures
$2K
>$500K 0.06%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
91 Install a passive containment spray system.
Improved containment spray capability.
19.52% 36.96% CONT01 No failures due to containment overpressure
$793K
>$10M 31.32%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
93 Install an unfiltered, hardened containment vent.
Increased decay heat removal capability for non-ATWS events, without scrubbing released fission products.
19.52% 36.96% CONT01 No failures due to containment overpressure
$793K
>$2M 31.32%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
94 Install a filtered containment vent to remove decay heat.
Option 1: Gravel Bed Filter; Option 2: Multiple Venturi Scrubber Increased decay heat removal capability for non-ATWS events, with scrubbing of released fission products.
19.52% 36.96% CONT01 No failures due to containment overpressure
$793K
>$2M 31.32%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
ULNRC-05919 October 17, 2012 Page 12 of 34 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway SAMA Number Potential Improvement Discussion
% Red.
In CDF
% Red.
In OS Dose SAMA Case SAMA Case Description Benefit Cost
% Red IN OECR Cost Basis Evaluation Basis for Evaluation 96 Provide post-accident containment inerting capability.
Reduced likelihood of hydrogen and carbon monoxide gas combustion.
0.48%
0.00%
H2BURN No hydrogen burns/explosions
$10K
>$100K 0.44%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
97 Create a large concrete crucible with heat removal potential to contain molten core debris.
Increased cooling and containment of molten core debris. Molten core debris escaping from the vessel is contained within the crucible and a water cooling mechanism cools the molten core in the crucible, preventing melt-through of the base mat.
MAB
>$10M Note 1 Expert Panel Not Cost-Beneficial Cost will exceed benefit.
98 Create a core melt source reduction system.
Increased cooling and containment of molten core debris. Refractory material would be placed underneath the reactor vessel such that a molten core falling on the material would melt and combine with the material.
Subsequent spreading and heat removal from the vitrified compound would be facilitated, and concrete attack would not occur.
MAB
>$10M Note 1 Expert Panel Not Cost-Beneficial Cost will exceed benefit.
99 Strengthen primary/secondary containment (e.g., add ribbing to containment shell).
Reduced probability of containment over-pressurization.
19.52% 36.96% CONT01 No failures due to containment overpressure
$1.2M
>$10M 31.32%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
100 Increase depth of the concrete base mat or use an alternate concrete material to ensure melt-through does not occur.
Reduced probability of base mat melt-through.
MAB
>$10M Note 1 Expert Panel Not Cost-Beneficial Cost will exceed benefit.
102 Construct a building to be connected to primary/secondary containment and maintained at a vacuum.
Reduced probability of containment over-pressurization.
19.52% 36.96% CONT01 No failures due to containment overpressure
$1.2M
>$10M 31.32%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
104 Improve leak detection procedures.
Increased piping surveillance to identify leaks prior to complete failure. Improved leak detection would reduce LOCA frequency.
39.34%
2.17%
LOCA05 No piping system LOCAs
$689K
>$2M 1.03%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
107 Install a redundant containment spray system.
Increased containment heat removal ability.
19.52% 36.96% CONT01 No failures due to containment overpressure
$1.2M
>$2M 31.32%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
ULNRC-05919 October 17, 2012 Page 13 of 34 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway SAMA Number Potential Improvement Discussion
% Red.
In CDF
% Red.
In OS Dose SAMA Case SAMA Case Description Benefit Cost
% Red IN OECR Cost Basis Evaluation Basis for Evaluation 108 Install an independent power supply to the hydrogen control system using either new batteries, a non-safety grade portable generator, existing station batteries, or existing AC/DC independent power supplies, such as the security system diesel.
Reduced hydrogen detonation potential.
0.48%
0.00%
H2BURN No hydrogen burns/explosions
$10K
>$100K 0.44%
Expert Panel Not Cost-Beneficial 109 Install a passive hydrogen control system.
Reduced hydrogen detonation potential.
0.48%
0.00%
H2BURN No hydrogen burns/explosions
$10K
>$100M 0.44%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
110 Erect a barrier that would provide enhanced protection of the containment walls (shell) from ejected core debris following a core melt scenario at high pressure.
Reduced probability of containment failure.
MAB
>$10M Note 1 Expert Panel Not Cost-Beneficial Cost will exceed benefit.
111 Install additional pressure or leak monitoring instruments for detection of ISLOCAs.
Reduced ISLOCA frequency.
1.33%
8.70%
$123K
>$500K 7.08%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
112 Add redundant and diverse limit switches to each containment isolation valve.
Reduced frequency of containment isolation failure and ISLOCAs.
0.30%
0.00%
CONT02 No failures of containment isolation
$1K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
113 Increase leak testing of valves in ISLOCA paths.
Reduced ISLOCA frequency.
1.33%
8.70%
$123K
>$1M 7.08%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
114 Install self-actuating containment isolation valves.
Reduced frequency of isolation failure.
0.30%
0.00%
CONT02 No failures of containment isolation
$1K
>$500K 0.03%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
115 Locate residual heat removal (RHR) inside containment Reduced frequency of ISLOCA outside containment.
1.33%
8.70%
$123K
>$1M 7.08%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
116 Ensure ISLOCA releases are scrubbed. One method is to plug drains in potential break areas so that break point will be covered with water.
Scrubbed ISLOCA releases.
1.33%
8.70%
$123K
>$1M 7.08%
Expert Panel Not Cost-Beneficial Cost would exceed benefit.
Current plant design requires drains to be open.
Analysis and license changes required to implement are included in the cost estimate.
119 Institute a maintenance practice to perform a 100%
inspection of steam generator tubes during each refueling outage.
Reduced frequency of steam generator tube ruptures.
20.47%
63.28% NOSGTR No SGTR Events
$1.4M
>$3M 69.43%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
121 Increase the pressure capacity of the secondary side so that a steam generator tube rupture would not cause the relief valves to lift.
Eliminates release pathway to the environment following a steam generator tube rupture.
20.47%
63.28% NOSGTR No SGTR Events
$1.4M
>$10M 69.43%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
ULNRC-05919 October 17, 2012 Page 14 of 34 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway SAMA Number Potential Improvement Discussion
% Red.
In CDF
% Red.
In OS Dose SAMA Case SAMA Case Description Benefit Cost
% Red IN OECR Cost Basis Evaluation Basis for Evaluation 122 Install a redundant spray system to depressurize the primary system during a steam generator tube rupture Enhanced depressurization capabilities during steam generator tube rupture.
20.47%
63.28% NOSGTR No SGTR Events
$1.4M
>$10M 69.43%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
125 Route the discharge from the main steam safety valves through a structure where a water spray would condense the steam and remove most of the fission products.
Reduced consequences of a steam generator tube rupture.
20.47%
63.28% NOSGTR No SGTR Events
$1.4M
>$10M 69.43%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
126 Install a highly reliable (closed loop) steam generator shell-side heat removal system that relies on natural circulation and stored water sources Reduced consequences of a steam generator tube rupture.
20.47%
63.28% NOSGTR No SGTR Events
$1.4M
>$10M 69.43%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
129 Vent main steam safety valves in containment.
Reduced consequences of a steam generator tube rupture.
20.47%
63.28% NOSGTR No SGTR Events
$1.4M
>$10M 69.43%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
Current containment design does not support this modification.
Modifications to containment and associated analysis are included in the cost estimate.
130 Add an independent boron injection system.
Improved availability of boron injection during ATWS.
2.41%
2.17%
NOATWS Eliminate all ATWS
$63K
>$1M 1.85%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
131 Add a system of relief valves to prevent equipment damage from pressure spikes during an ATWS.
Improved equipment availability after an ATWS.
2.41%
2.17%
NOATWS Eliminate all ATWS
$63K
>$2M 1.85%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
133 Install an ATWS sized filtered containment vent to remove decay heat.
Increased ability to remove reactor heat from ATWS events.
2.41%
2.17%
NOATWS Eliminate all ATWS
$63K
>$1M 1.85%
Expert Panel Not Cost-Beneficial Cost will exceed benefit 136 Install motor generator set trip breakers in control room.
Reduced frequency of core damage due to an ATWS.
2.41%
2.17%
NOATWS Eliminate all ATWS
$63K
>$500K 1.85%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
147 Install digital large break LOCA protection system.
Reduced probability of a large break LOCA (a leak before break).
39.34%
2.17%
LOCA05 No piping system LOCAs
$689K
>$5M 1.03%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
153 Install secondary side guard pipes up to the main steam isolation valves.
Prevents secondary side depressurization should a steam line break occur upstream of the main steam isolation valves.
Also guards against or prevents consequential multiple steam generator tube ruptures following a main steam line break event.
2.53%
0.00%
NOSLB No Steam Line Breaks
$51K
>$1M 0.87%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
ULNRC-05919 October 17, 2012 Page 15 of 34 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway SAMA Number Potential Improvement Discussion
% Red.
In CDF
% Red.
In OS Dose SAMA Case SAMA Case Description Benefit Cost
% Red IN OECR Cost Basis Evaluation Basis for Evaluation 160 Modifications to lessen impact of internal flooding path through Control Building dumbwaiter.
Lower impact of flood that propagates through the dumbwaiter
<$50K Expert Panel Potentially Cost-Beneficial Relatively minor modifications to door opening could result in lower flow to the dumbwaiter. Specific benefit could not be calculated but SAMA item is judged to be low cost and therefore potentially cost beneficial.
161 Improvements to PORV performance that will lower the probability of failure to open.
Decrease in risk due to PORV failing to open.
0.85%
0.46%
PORV PORVs do not fail to open
$18K
>$100K 0.24%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
162 Install a large volume EDG fuel oil tank at an elevation greater than the EDG fuel oil day tanks.
Allows transfer of EDF fuel oil to the EDG day tanks on failure of the fuel oil transfer pumps.
1.14%
7.60%
EDGFUEL No EDG fuel pump failures
$124K
$150K 7.11%
Wolf Creek Potentially Cost-Beneficial Wolf Creek estimated cost of $150K is less than the potential benefit.
163 Improve feedwater check valve reliability to reduce probability of failure to open.
Lower risk due to failures in which feedwater check valves fail to open and allow feeding of the steam generators.
5.52%
2.05%
FW02 Feedwater Check Valves do not fail to open
$127K
>$500K 2.23%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
164 Provide the capability to power the normal service water pumps from AEPS.
Provide backup to ESW in conditions with power only available from AEPS.
5.62%
7.64%
SW03 AEPS power to SW pumps
$191K
>$500K 6.37%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
171 Increase the size of the RWST or otherwise improve the availability of the RWST Ensure a supply of makeup water is available from the RWST.
0.68%
0.13%
LOCA04 RWST does not deplete
$13K
>$100K 0.07%
Expert Panel Not Cost-Beneficial Cost will exceed benefit.
178 Improvements to UHS cooling tower electrical room HVAC.
Improve availability or mitigate loss of HVAC.
3.29%
4.75%
HVAC02 UHS cooling tower electrical room HVAC does not fail.
$113K
<$100K 3.82%
Expert Panel Potentially Cost Beneficial Implementation of temporary ventilation or opening of doors will be a lower cost than the calculated benefit.
179 Modify procedures such that the water loop seals in the RCS cold legs are not cleared following core damage.
Prevents possible thermally induced steam generator tube rupture following core damage.
0.15%
3.18%
RAI7a Reduced probability of thermally induced steam generator tube failure
$63K
<$100K 4.46%
Expert Panel Potentially Cost Beneficial Implementation of procedure change will be lower cost than benefit, especially if 95% CDF benefit is considered.
180 Install lower amperage fuses for various 14 AWG control circuits in the MCR. The majority of the modification centers around the trip circuit fuses on NB, NG, PA, PB, and PG system breakers.
Reduced fire risk.
Potentially Cost Beneficial SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
ULNRC-05919 October 17, 2012 Page 16 of 34 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway SAMA Number Potential Improvement Discussion
% Red.
In CDF
% Red.
In OS Dose SAMA Case SAMA Case Description Benefit Cost
% Red IN OECR Cost Basis Evaluation Basis for Evaluation 181 Install redundant fuses and isolation switches for MCR evacuation procedure OTO-ZZ-00001.
Reduced fire risk.
Potentially Cost Beneficial SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
182 To protect against multiple spurious operation scenarios, cable runs will be changed to run a single wire in a protected metal jacket such that spurious valve opening due to a hot short affecting the valve control circuit is eliminated for the fire area.
This modification will be implemented in multiple fire areas.
Reduced fire risk.
Potentially Cost Beneficial SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
183 Quick response sprinkler heads in cable chases A-11, C-30, and C-31 will be modified to be in accordance with the applicable requirements of NFPA 13-1976 edition.
Reduced fire risk.
Potentially Cost Beneficial SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
184 Improvements in the reliability of the Steam Line Isolation automatic signal.
More reliable main steam line isolation.
0.59%
0.95%
SLIS Steam Line Isolation System does not fail
$28K
>$500K 1.06%
Expert Panel Not Cost-Beneficial Cost is for installation of redundant instrumentation system and would likely be much higher. Procedure and training already direct operators to manually back up failed automatic actuations.
185 Automate initiation of CCW flow to the RHR heat exchangers.
More reliable than manual initiation of flow to RHR HX.
3.53%
0.14%
HEP Evaluate automating CCW flow to RHR HXs
$62K
$200K 0.11%
Expert Panel Potentially Cost Beneficial 186 Develop a procedure and obtain equipment to provide a temporary hookup of fire water as a replacement for ESW Backup cooling water if ESW/SW is lost 0.04%
0.05%
FWCCW Fire water available to cool CCW HX
$1K
>$1M 0.04%
Expert Panel Not Cost-Beneficial Ability to do this will require larger fire pumps.
187 Install modification to power the normal charging pump from an existing spare breaker from the AEPS.
Another source of backup power to the NCP in cases of station blackout or loss of service water 4.07%
7.63%
SBOMOD Reduce the frequency of SBO sequences.
$174K
$350K 7.03%
Expert Panel Potentially Cost Beneficial Already installed spare circuit breaker, implementation requires power and control cables.
ULNRC-05919 October 17, 2012 Page 17 of 34 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway SAMA Number Potential Improvement Discussion
% Red.
In CDF
% Red.
In OS Dose SAMA Case SAMA Case Description Benefit Cost
% Red IN OECR Cost Basis Evaluation Basis for Evaluation 188 Install a permanent, dedicated generator for the NCP, and a motor-driven AFW pump and battery charger to address SBO events in which the TD AFW pump is unavailable.
Another source of backup power to the NCP, DC power (pump/valve control and SG level instrumentation), and power to an AFW pump in cases of station blackout or loss of service water 4.28%
7.63%
SBOMOD2 Reduce the frequency of SBO sequences.
$182K
$400K 7.38%
Expert Panel Potentially Cost Beneficial AEPS was installed with a spare breaker and expansion capability that could be used to supply various equipment.
OS = off site Note 1: For SAMA items that were judged to cost significantly more than the Maximum Attainable Benefit (MAB), no calculation of the individual benefit was performed.
ULNRC-05919 October 17, 2012 Page 18 of 34 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway SAMA Number Potential Improvement Discussion SAMA Case Benefit Benefit at 3% Disc Rate Benefit at Realistic Disc Rate Benefit at 33yrs Benefit at 95%
CDF Cost Cost Basis Evaluation Basis for Evaluation 1
Provide additional DC battery capacity.
Extended DC power availability during an SBO.
NOSBO
$360K
$588K
$325K
$512K
$761K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
2 Replace lead-acid batteries with fuel cells.
Extended DC power availability during an SBO.
NOSBO
$360K
$588K
$325K
$512K
$761K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
5 Provide DC bus cross-ties.
Improved availability of DC power system.
DC01
$1K
$1K
$1K
$1K
$1K
>$199K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
11 Improve 4.16-kV bus cross-tie ability. Increased availability of on-site AC power.
4kv2
$13K
$20K
$12K
$17K
$27K
<$100K Expert Panel Potentially Cost-Beneficial Physical cross-tie exists, but there is no analysis or procedures to allow its use except in specific outage conditions. Cost is to develop procedures and analysis to allow use of the cross-tie.
Benefit calculated is under-estimated since it was evaluated for only SBO sequences.
15 Install tornado protection on gas turbine generator.
Increased availability of on-site AC power.
LOSP1
$91K
$144K
$82K
$125K
$192K
>$500K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
24 Bury off-site power lines.
Improved off-site power reliability during severe weather.
NOLOSP
$1.2M
$2.0M
$1.1M
$1.7M
$2.6M
>$3M Expert Panel Not Cost-Beneficial Cost will exceed benefit. Previous SAMA submittals have estimated approximately $1M per mile.
25 Install an independent active or passive high pressure injection system.
Improved prevention of core melt sequences.
LOCA12
$48K
$85K
$44K
$75
$102
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
26 Provide an additional high pressure injection pump with independent diesel.
Reduced frequency of core melt from small LOCA and SBO sequences.
LOCA12
$48K
$85K
$44K
$75
$102
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
28 Add a diverse low pressure injection system.
Improved injection capability.
LOCA03
$65K
$111K
$58K
$97K
$137K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
29 Provide capability for alternate injection via diesel-driven fire pump.
Improved injection capability.
Potentially Cost-Beneficial SAMA is judged to be low cost, but analysis is needed to determine impacts of injection of non-borated water to RCS.
Expert Panel judged this SAMA to be potentially cost-beneficial without determining an actual benefit or cost.
ULNRC-05919 October 17, 2012 Page 19 of 34 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway SAMA Number Potential Improvement Discussion SAMA Case Benefit Benefit at 3% Disc Rate Benefit at Realistic Disc Rate Benefit at 33yrs Benefit at 95%
CDF Cost Cost Basis Evaluation Basis for Evaluation 39 Replace two of the four electric safety injection pumps with diesel-powered pumps.
Reduced common cause failure of the safety injection system.
This SAMA was originally intended for the Westinghouse-CE System 80+, which has four trains of safety injection.
However, the intent of this SAMA is to provide diversity within the high-and l LOCA12
$48K
$85K
$44K
$75
$102
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
41 Create a reactor coolant depressurization system.
Allows low pressure emergency core cooling system injection in the event of small LOCA and high-pressure safety injection failure.
DEPRESS
$12K
$20K
$11K
$17K
$25K
>$500K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
43 Add redundant DC control power for SW pumps.
Increased availability of SW.
SW01
$1K
$2K
$1K
$2K
$3K
>$100K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
46 Add a service water pump.
Increased availability of cooling water.
SW02
$636K
$1M
$575K
$879K
$1.3M
>$5M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
54 Increase charging pump lube oil capacity.
Increased time before charging pump failure due to lube oil overheating in loss of cooling water sequences.
CHG01
$4K
$7K
$4K
$6K
$9K
>$100K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
55 Install an independent reactor coolant pump seal injection system, with dedicated diesel.
Reduced frequency of core damage from loss of component cooling water, service water, or station blackout.
RCPLOCA
$94K
$168K
$85K
$148K
$198K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit. Previous investigation into installing such a system concluded that operators did not have sufficient time to place the system in service prior to seal damage.
56 Install an independent reactor coolant pump seal injection system, without dedicated diesel.
Reduced frequency of core damage from loss of component cooling water or service water, but not a station blackout.
RCPLOCA
$94K
$168K
$85K
$148K
$198K
>$500K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
58 Install improved reactor coolant pump seals.
Reduced likelihood of reactor coolant pump seal LOCA.
RCPLOCA
$94K
$168K
$85K
$148K
$198K
>$3M Not Cost-Beneficial Cost will exceed benefit.
59 Install an additional component cooling water pump.
Reduced likelihood of loss of component cooling water leading to a reactor coolant pump seal LOCA.
CCW01
$59K
$106K
$53K
$93K
$124K
>$1M Cost will exceed benefit Not Cost-Beneficial Cost will exceed benefit.
64 Implement procedure and hardware modifications to allow manual alignment of the fire water system to the component cooling water system, or install a component cooling water header cross-tie.
Improved ability to cool residual heat removal heat exchangers.
FWCCW2
$104K
$184K
$94K
$161K
$220K
<$150K Expert Panel Potentially Cost Beneficial The cost estimate is for development of a procedure and use of temporary connections. Cost of permanent modification would be significantly higher.
ULNRC-05919 October 17, 2012 Page 20 of 34 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway SAMA Number Potential Improvement Discussion SAMA Case Benefit Benefit at 3% Disc Rate Benefit at Realistic Disc Rate Benefit at 33yrs Benefit at 95%
CDF Cost Cost Basis Evaluation Basis for Evaluation 65 Install a digital feed water upgrade.
Reduced chance of loss of main feed water following a plant trip.
FW01
$29K
$50K
$27K
$44K
$62K
$19M Callaway Modification Costs Not Cost-Beneficial Cost will exceed benefit.
71 Install a new condensate storage tank (auxiliary feedwater storage tank).
Increased availability of the auxiliary feedwater system.
CST01
$18K
$32K
$16K
$28K
$39K
>$2.5M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
77 Provide a passive, secondary-side heat-rejection loop consisting of a condenser and heat sink.
Reduced potential for core damage due to loss-of-feedwater events.
FW01
$29K
$50K
$27K
$44K
$62K
$>1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
79 Replace existing pilot-operated relief valves with larger ones, such that only one is required for successful feed and bleed.
Increased probability of successful feed and bleed.
FB01
$79K
$133K
$72K
$117K
$168K
>$500K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
80 Provide a redundant train or means of ventilation.
Increased availability of components dependent on room cooling.
$156K
$259K
$141K
$227K
$331K
<$100K Expert Panel Potentially Cost Beneficial Procedures to open doors or provide temporary ventilation may be cost beneficial for the EDGs, MDAFW pumps, and charging pumps. Procedures for opening doors to the DC switchgear rooms exist.
87 Replace service and instrument air compressors with more reliable compressors which have self-contained air cooling by shaft driven fans.
Elimination of instrument air system dependence on service water cooling.
INSTAIR
$2K
$3K
$2K
$$2K
$4K
>$500K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
91 Install a passive containment spray system.
Improved containment spray capability.
CONT01
$793K
$1.2M
$717K
$1.1M
$1.7M
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
93 Install an unfiltered, hardened containment vent.
Increased decay heat removal capability for non-ATWS events, without scrubbing released fission products.
CONT01
$793K
$1.2M
$717K
$1.1M
$1.7M
>$2M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
94 Install a filtered containment vent to remove decay heat. Option 1: Gravel Bed Filter; Option 2: Multiple Venturi Scrubber Increased decay heat removal capability for non-ATWS events, with scrubbing of released fission products.
CONT01
$793K
$1.2M
$717K
$1.1M
$1.7M
>$2M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
96 Provide post-accident containment inerting capability.
Reduced likelihood of hydrogen and carbon monoxide gas combustion.
H2BURN
$10K
$15K
$9K
$13K
$20K
>$100K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
97 Create a large concrete crucible with heat removal potential to contain molten core debris.
Increased cooling and containment of molten core debris. Molten core debris escaping from the vessel is contained within the crucible and a water cooling mechanism cools the molten core in the crucible, preventing melt-through of the base mat.
MAB
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
ULNRC-05919 October 17, 2012 Page 21 of 34 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway SAMA Number Potential Improvement Discussion SAMA Case Benefit Benefit at 3% Disc Rate Benefit at Realistic Disc Rate Benefit at 33yrs Benefit at 95%
CDF Cost Cost Basis Evaluation Basis for Evaluation 98 Create a core melt source reduction system.
Increased cooling and containment of molten core debris. Refractory material would be placed underneath the reactor vessel such that a molten core falling on the material would melt and combine with the material. Subsequent spreading and heat removal from the vitrified compound would be facilitated, and concrete attack would not occur.
MAB
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
99 Strengthen primary/secondary containment (e.g., add ribbing to containment shell).
Reduced probability of containment over-pressurization.
CONT01
$1.2M
$1.2M
$717K
$1.1M
$1.7M
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
100 Increase depth of the concrete base mat or use an alternate concrete material to ensure melt-through does not occur.
Reduced probability of base mat melt-through.
MAB
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
102 Construct a building to be connected to primary/secondary containment and maintained at a vacuum.
Reduced probability of containment over-pressurization.
CONT01
$1.2M
$1.2M
$717K
$1.1M
$1.7M
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
104 Improve leak detection procedures.
Increased piping surveillance to identify leaks prior to complete failure. Improved leak detection would reduce LOCA frequency.
LOCA05
$685K
$1.2M
$620K
$1.1M
$1.5M
>$2M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
107 Install a redundant containment spray system.
Increased containment heat removal ability.
CONT01
$1.2M
$1.2M
$717K
$1.1M
$1.7M
>$2M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
108 Install an independent power supply to the hydrogen control system using either new batteries, a non-safety grade portable generator, existing station batteries, or existing AC/DC independent power supplies, such as the security system diesel.
Reduced hydrogen detonation potential.
H2BURN
$10K
$15K
$9K
$13K
$20K
>$100K Expert Panel Not Cost-Beneficial 109 Install a passive hydrogen control system.
Reduced hydrogen detonation potential.
H2BURN
$10K
$15K
$9K
$13K
$20K
>$100M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
110 Erect a barrier that would provide enhanced protection of the containment walls (shell) from ejected core debris following a core melt scenario at high pressure.
Reduced probability of containment failure.
MAB
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
111 Install additional pressure or leak monitoring instruments for detection of ISLOCAs.
Reduced ISLOCA frequency.
$123K
$179K
$111K
$154K
$259K
>$500K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
112 Add redundant and diverse limit switches to each containment isolation valve.
Reduced frequency of containment isolation failure and ISLOCAs.
CONT02
$1K
$1K
$1K
$1K
$2K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
113 Increase leak testing of valves in ISLOCA paths.
Reduced ISLOCA frequency.
$123K
$179K
$111K
$154K
$259K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
ULNRC-05919 October 17, 2012 Page 22 of 34 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway SAMA Number Potential Improvement Discussion SAMA Case Benefit Benefit at 3% Disc Rate Benefit at Realistic Disc Rate Benefit at 33yrs Benefit at 95%
CDF Cost Cost Basis Evaluation Basis for Evaluation 114 Install self-actuating containment isolation valves.
Reduced frequency of isolation failure.
CONT02
$1K
$1K
$1K
$1K
$2K
>$500K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
115 Locate residual heat removal (RHR) inside containment Reduced frequency of ISLOCA outside containment.
$123K
$179K
$111K
$154K
$259K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
116 Ensure ISLOCA releases are scrubbed. One method is to plug drains in potential break areas so that break point will be covered with water.
Scrubbed ISLOCA releases.
$123K
$179K
$111K
$154K
$259K
>$1M Expert Panel Not Cost-Beneficial Cost would exceed benefit. Current plant design requires drains to be open.
Analysis and license changes required to implement are included in the cost estimate.
119 Institute a maintenance practice to perform a 100% inspection of steam generator tubes during each refueling outage.
Reduced frequency of steam generator tube ruptures.
NOSGTR
$1.4M
$2.1M
$1.2M
$1.8M
$2.9M
>$3M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
121 Increase the pressure capacity of the secondary side so that a steam generator tube rupture would not cause the relief valves to lift.
Eliminates release pathway to the environment following a steam generator tube rupture.
NOSGTR
$1.4M
$2.1M
$1.2M
$1.8M
$2.9M
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
122 Install a redundant spray system to depressurize the primary system during a steam generator tube rupture Enhanced depressurization capabilities during steam generator tube rupture.
NOSGTR
$1.4M
$2.1M
$1.2M
$1.8M
$2.9M
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
125 Route the discharge from the main steam safety valves through a structure where a water spray would condense the steam and remove most of the fission products.
Reduced consequences of a steam generator tube rupture.
NOSGTR
$1.4M
$2.1M
$1.2M
$1.8M
$2.9M
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
126 Install a highly reliable (closed loop) steam generator shell-side heat removal system that relies on natural circulation and stored water sources Reduced consequences of a steam generator tube rupture.
NOSGTR
$1.4M
$2.1M
$1.2M
$1.8M
$2.9M
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
129 Vent main steam safety valves in containment.
Reduced consequences of a steam generator tube rupture.
NOSGTR
$1.4M
$2.1M
$1.2M
$1.8M
$2.9M
>$10M Expert Panel Not Cost-Beneficial Cost will exceed benefit. Current containment design does not support this modification.
Modifications to containment and associated analysis are included in the cost estimate.
130 Add an independent boron injection system.
Improved availability of boron injection during ATWS.
NOATWS
$63K
$104K
$57K
$90K
$134K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
131 Add a system of relief valves to prevent equipment damage from pressure spikes during an ATWS.
Improved equipment availability after an ATWS.
NOATWS
$63K
$104K
$57K
$90K
$134K
>$2M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
ULNRC-05919 October 17, 2012 Page 23 of 34 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway SAMA Number Potential Improvement Discussion SAMA Case Benefit Benefit at 3% Disc Rate Benefit at Realistic Disc Rate Benefit at 33yrs Benefit at 95%
CDF Cost Cost Basis Evaluation Basis for Evaluation 133 Install an ATWS sized filtered containment vent to remove decay heat.
Increased ability to remove reactor heat from ATWS events.
NOATWS
$63K
$104K
$57K
$90K
$134K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit 136 Install motor generator set trip breakers in control room.
Reduced frequency of core damage due to an ATWS.
NOATWS
$63K
$104K
$57K
$90K
$134K
>$500K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
147 Install digital large break LOCA protection system.
Reduced probability of a large break LOCA (a leak before break).
LOCA05
$689K
$1.2M
$620K
$1.1M
$1.5M
>$5M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
153 Install secondary side guard pipes up to the main steam isolation valves.
Prevents secondary side depressurization should a steam line break occur upstream of the main steam isolation valves.
Also guards against or prevents consequential multiple steam generator tube ruptures following a main steam line break event.
NOSLB
$51K
$87K
$46K
$77K
$108K
>$1M Expert Panel Not Cost-Beneficial Cost will exceed benefit.
160 Modifications to lessen impact of internal flooding path through Control Building dumbwaiter.
Lower impact of flood that propagates through the dumbwaiter
<$50K Expert Panel Potentially Cost-Beneficial Relatively minor modifications to door opening could result in lower flow to the dumbwaiter. Specific benefit could not be calculated but SAMA item is judged to be low cost and therefore potentially cost beneficial.
161 Improvements to PORV performance that will lower the probability of failure to open.
Decrease in risk due to PORV failing to open.
$18K
$32K
$16K
$28K
$39K
>$100K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
162 Install a large volume EDG fuel oil tank at an elevation greater than the EDG fuel oil day tanks.
Allows transfer of EDF fuel oil to the EDG day tanks on failure of the fuel oil transfer pumps.
EDGFUEL
$124K
$131K
$113K
$156K
$263K
$150K Wolf Creek Potentially Cost-Beneficial Wolf Creek estimated cost of $150K is less than the potential benefit.
163 Improve feedwater check valve reliability to reduce probability of failure to open.
Lower risk due to failures in which feedwater check valves fail to open and allow feeding of the steam generators.
FW02
$127K
$218K
$115K
$191K
$270K
>$500K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
164 Provide the capability to power the normal service water pumps from AEPS.
Provide backup to ESW in conditions with power only available from AEPS.
SW03
$1191K
$307K
$172K
$267K
$403K
>$500K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
171 Increase the size of the RWST or otherwise improve the availability of the RWST Ensure a supply of makeup water is available from the RWST.
LOCA04
$13K
$23K
$12K
$20K
$27K
>$100K Expert Panel Not Cost-Beneficial Cost will exceed benefit.
178 Improvements to UHS cooling tower electrical room HVAC.
Improve availability or mitigate loss of HVAC.
HVAC02
$113K
$181K
$102K
$158K
$239K
<$100K Expert Panel Potentially Cost Beneficial Implementation of temporary ventilation or opening of doors will be a lower cost than the calculated benefit.
ULNRC-05919 October 17, 2012 Page 24 of 34 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway SAMA Number Potential Improvement Discussion SAMA Case Benefit Benefit at 3% Disc Rate Benefit at Realistic Disc Rate Benefit at 33yrs Benefit at 95%
CDF Cost Cost Basis Evaluation Basis for Evaluation 179 Modify procedures such that the water loop seals in the RCS cold legs are not cleared following core damage.
Prevents possible thermally induced steam generator tube rupture following core damage.
RAI7a
$63K
$87K
$57K
$75K
$134K
<$100K Expert Panel Potentially Cost Beneficial Implementation of procedure change will be lower cost than benefit, especially if 95%
CDF benefit is considered.
180 Install lower amperage fuses for various 14 AWG control circuits in the MCR. The majority of the modification centers around the trip circuit fuses on NB, NG, PA, PB, and PG system breakers.
Reduced fire risk.
Potentially Cost Beneficial SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
181 Install redundant fuses and isolation switches for MCR evacuation procedure OTO-ZZ-00001.
Reduced fire risk.
Potentially Cost Beneficial SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
182 To protect against multiple spurious operation scenarios, cable runs will be changed to run a single wire in a protected metal jacket such that spurious valve opening due to a hot short affecting the valve control circuit is eliminated for the fire area. This modification will be implemented in multiple fire areas.
Reduced fire risk.
Potentially Cost Beneficial SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
183 Quick response sprinkler heads in cable chases A-11, C-30, and C-31 will be modified to be in accordance with the applicable requirements of NFPA 13-1976 edition.
Reduced fire risk.
Potentially Cost Beneficial SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
ULNRC-05919 October 17, 2012 Page 25 of 34 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway SAMA Number Potential Improvement Discussion SAMA Case Benefit Benefit at 3% Disc Rate Benefit at Realistic Disc Rate Benefit at 33yrs Benefit at 95%
CDF Cost Cost Basis Evaluation Basis for Evaluation 184 Improvements in the reliability of the Steam Line Isolation automatic signal.
More reliable main steam line isolation.
SLIS
$28K
$40K
$23K
$35K
$55K
>$500K Expert Panel Not Cost-Beneficial Cost is for installation of redundant instrumentation system and would likely be much higher.
Procedure and training already direct operators to manually back up failed automatic actuations.
185 Automate initiation of CCW flow to the RHR heat exchangers.
More reliable than manual initiation of flow to RHR HX.
$62K
$112K
$56K
$99K
$132K
>$200K Expert Panel Potentially Cost Beneficial 186 Develop a procedure and obtain equipment to provide a temporary hookup of fire water to the RHR heat exchangers to use as a backup to CCW for removing decay heat.
Backup method of removing decay heat if CCW is lost.
FWCCW
$1K
$2K
$1K
$2K
$2K
>$1M Expert Panel Not Cost Beneficial Ability to do this will require larger fire pumps 187 Install modification to power the normal charging pump from an existing spare breaker from the AEPS.
Another source of backup power to the NCP in cases of station blackout or loss of service water SBOMOD
$174K
$272K
$157K
$236K
$367K
$350K Expert Panel Potentially Cost Beneficial Already installed spare circuit breaker, implementation requires power and control cables.
188 Install a permanent, dedicated generator for the NCP, and a motor-driven AFW pump and battery charger to address SBO events in which the TD AFW pump is unavailable.
Another source of backup power to the NCP, DC power (pump/valve control and SG level instrumentation), and power to an AFW pump in cases of station blackout or loss of service water SBOMOD2
$182K
$285K
$165K
$247K
$385K
$400K Expert Panel Potentially Cost Beneficial AEPS was installed with a spare breaker and expansion capability that could be used to supply various equipment.
ULNRC-05919 October 17, 2012 Page 26 of 34 Table 9-1. Callaway Plant Potentially Cost Beneficial SAMAs Callaway SAMA Number Potential Improvement Discussion Additional Discussion 11 Improve 4.16-kV bus cross-tie ability.
Increased availability of on-site AC power.
Physical cross-tie exists, but there is no analysis or procedures to allow its use except in specific outage conditions. Cost is to develop procedures and analysis to allow use of the cross-tie.
Benefit calculated is under-estimated since it was evaluated for only SBO sequences.
29 Provide capability for alternate injection via diesel-driven fire pump.
Improved injection capability.
Currently being evaluated by plant improvement program.
Would use unborated water and portable pump (fire truck).
Calculation of specific benefit of this SAMA was not performed since it is judged to be potentially low cost.
Evaluation will consider impacts of injection of non-borated water.
64 Implement procedure and hardware modifications to allow manual alignment of the fire water system to the component cooling water system, or install a component cooling water header cross-tie.
Improved ability to cool residual heat removal heat exchangers.
Cost based on development of procedure for temporary hookup of fire water to CCW heat exchangers.
Cost of permanent modification would be much greater.
ULNRC-05919 October 17, 2012 Page 27 of 34 Table 9-1. Callaway Plant Potentially Cost Beneficial SAMAs Callaway SAMA Number Potential Improvement Discussion Additional Discussion 80 Provide a redundant train or means of ventilation.
Increased availability of components dependent on room cooling.
Procedures to open doors or provide temporary ventilation may be cost beneficial for the EDGs, MDAFW pumps, and charging pumps. Procedures for opening doors to the DC switchgear rooms exist.
160 Modifications to lessen impact of internal flooding path through Control Building dumbwaiter.
Lower impact of flood that propagates through the dumbwaiter 162 Install a large volume EDG fuel oil tank at an elevation greater than the EDG fuel oil day tanks.
Allows transfer of EDG fuel oil to the EDG day tanks on failure of the fuel oil transfer pumps.
178 Improvements to UHS cooling tower electrical room HVAC.
Improve availability or mitigate loss of HVAC.
Implementation of temporary ventilation or opening of doors will be a lower cost than the calculated benefit.
179 Modify procedures such that the water loop seals in the RCS cold legs are not cleared following core damage.
Prevents possible thermally induced steam generator tube rupture following core damage.
Implementation of procedure change will be lower cost than benefit, especially if 95% CDF benefit is considered.
ULNRC-05919 October 17, 2012 Page 28 of 34 Table 9-1. Callaway Plant Potentially Cost Beneficial SAMAs Callaway SAMA Number Potential Improvement Discussion Additional Discussion 180 Install lower amperage fuses for various 14 AWG control circuits in the MCR.
The majority of the modification centers around the trip circuit fuses on NB, NG, PA, PB, and PG system breakers.
Reduced fire risk.
SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
181 Install redundant fuses and isolation switches for MCR evacuation procedure OTO-ZZ-00001.
Reduced fire risk.
SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
182 To protect against multiple spurious operation scenarios, cable runs will be changed to run a single wire in a protected metal jacket such that spurious valve opening due to a hot short affecting the valve control circuit is eliminated for the fire area. This modification will be implemented in multiple fire areas.
Reduced fire risk.
SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
ULNRC-05919 October 17, 2012 Page 29 of 34 Table 9-1. Callaway Plant Potentially Cost Beneficial SAMAs Callaway SAMA Number Potential Improvement Discussion Additional Discussion 183 Quick response sprinkler heads in cable chases A-11, C-30, and C-31 will be modified to be in accordance with the applicable requirements of NFPA 13-1976 edition.
Reduced fire risk.
SAMA considered potentially cost beneficial without benefit or cost determination since the NFPA 805 license amendment request committed to performing the modification.
185 Automate initiation of CCW flow to the RHR heat exchangers.
More reliable than manual initiation of flow to RHR HX.
187 Install modification to power the normal charging pump from an existing spare breaker from the AEPS.
Another source of backup power to the NCP in cases of station blackout or loss of service water Already installed spare circuit breaker, implementation requires power and control cables.
188 Install a permanent, dedicated generator for the NCP, and a motor-driven AFW pump and battery charger to address SBO events in which the TD AFW pump is unavailable.
Another source of backup power to the NCP, DC power (pump/valve control and SG level instrumentation), and power to an AFW pump in cases of station blackout or loss of service water AEPS was installed with a spare breaker and expansion capability that could be used to supply various equipment.
ULNRC-05919 October 17, 2012 Page 30 of 34 Table 11-1. Callaway Plant Release Category Frequency Results Obtained From SAMA Cases RELEASE CATEGORY BASE NOATWS INSTAIR NOLOSP NOSLOCA CCW01 FW01 NOSGTR NOSLB CHG01 LERF-IS 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 LERF-CI 1.658E-10 1.411E-10 1.658E-10 1.422E-10 6.210E-11 1.567E-10 1.658E-10 1.658E-10 1.610E-10 1.658E-10 LERF-CF 1.125E-08 1.103E-08 1.124E-08 7.372E-09 5.378E-09 1.071E-08 1.115E-08 1.135E-08 1.116E-08 1.123E-08 LERF-SG 2.331E-06 2.306E-06 2.330E-06 2.331E-06 2.331E-06 2.331E-06 2.331E-06 0.000E+00 2.331E-06 2.331E-06 LERF-ITR 2.170E-07 1.845E-07 2.167E-07 1.309E-07 2.072E-07 2.170E-07 2.052E-07 0.000E+00 1.936E-07 2.169E-07 LATE-BMT 2.551E-06 2.268E-06 2.547E-06 1.254E-07 2.022E-06 2.507E-06 2.448E-06 2.626E-06 2.515E-06 2.467E-06 LATE-COP 3.185E-06 3.185E-06 3.185E-06 1.796E-08 3.170E-06 3.185E-06 3.185E-06 2.234E-06 3.185E-06 3.185E-06 SERF 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 INTACT 8.080E-06 8.075E-06 8.080E-06 7.065E-06 2.540E-06 7.573E-06 7.983E-06 8.119E-06 7.773E-06 8.137E-06 TOTAL 1.655E-05 1.620E-05 1.654E-05 9.851E-06 1.045E-05 1.600E-05 1.634E-05 1.316E-05 1.618E-05 1.652E-05 Table 11-1. Callaway Plant Release Category Frequency Results Obtained From SAMA Cases (Cont.)
RELEASE CATEGORY SW01 NOSBO LOCA05 H2BURN RCPLOCA LOCA 12 CONT02 LOCA04 LOCA03 CONT01 LERF-IS 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 LERF-CI 1.658E-10 1.658E-10 6.210E-11 1.658E-10 1.567E-10 1.658E-10 0.000E+00 1.658E-10 1.658E-10 1.658E-10 LERF-CF 1.124E-08 1.030E-08 5.018E-09 4.102E-12 1.048E-08 1.099E-08 1.125E-08 1.114E-08 1.089E-08 1.125E-08 LERF-SG 2.331E-06 2.329E-06 2.331E-06 2.331E-06 2.331E-06 2.331E-06 2.331E-06 2.331E-06 2.298E-06 2.331E-06 LERF-ITR 2.170E-07 1.443E-07 2.072E-07 2.170E-07 2.170E-07 2.165E-07 2.170E-07 2.170E-07 2.169E-07 2.170E-07 LATE-BMT 2.553E-06 1.611E-06 2.009E-06 2.551E-06 2.475E-06 1.893E-06 2.551E-06 2.441E-06 2.007E-06 2.551E-06 LATE-COP 3.181E-06 2.426E-06 3.170E-06 3.170E-06 3.173E-06 3.182E-06 3.185E-06 3.185E-06 3.185E-06 0.000E+00 SERF 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 INTACT 8.080E-06 7.883E-06 2.170E-06 8.080E-06 7.301E-06 8.329E-06 8.080E-06 8.080E-06 8.180E-06 8.080E-06 TOTAL 1.655E-05 1.458E-05 1.007E-05 1.652E-05 1.568E-05 1.614E-05 1.655E-05 1.644E-05 1.607E-05 1.336E-05
ULNRC-05919 October 17, 2012 Page 31 of 34 Table 11-1. Callaway Plant Release Category Frequency Results Obtained From SAMA Cases RELEASE CATEGORY BREAKER DC01 SW02 CCW02 CST01 ISLOCA LOSP1 DEPRESS LOCA06 HVAC LERF-IS 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 0.000E+00 1.730E-07 1.730E-07 1.730E-07 1.730E-07 LERF-CI 1.666E-10 1.658E-10 1.514E-10 1.422E-10 1.650E-10 1.658E-10 1.666E-10 1.658E-10 1.658E-10 1.658E-10 LERF-CF 1.129E-08 1.124E-08 9.088E-09 8.906E-09 1.112E-08 1.125E-08 1.113E-08 1.122E-08 1.109E-08 1.099E-08 LERF-SG 2.328E-06 2.331E-06 2.331E-06 2.331E-06 2.331E-06 2.331E-06 2.331E-06 2.331E-06 2.331E-06 2.329E-06 LERF-ITR 2.093E-07 2.170E-07 2.013E-07 2.108E-07 2.169E-07 2.170E-07 1.814E-07 2.160E-07 2.169E-07 1.944E-07 LATE-BMT 2.047E-06 2.551E-06 2.213E-06 1.864E-06 2.022E-06 2.551E-06 2.039E-06 2.508E-06 2.020E-06 1.657E-06 LATE-COP 3.210E-06 3.185E-06 8.964E-07 1.455E-06 3.185E-06 3.185E-06 2.991E-06 3.166E-06 3.185E-06 2.917E-06 SERF 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 INTACT 8.180E-06 8.080E-06 7.898E-06 7.836E-06 8.471E-06 8.080E-06 8.431E-06 8.069E-06 8.431E-06 8.312E-06 TOTAL 1.616E-05 1.655E-05 1.372E-05 1.388E-05 1.641E-05 1.638E-05 1.616E-05 1.647E-05 1.637E-05 1.559E-05
ULNRC-05919 October 17, 2012 Page 32 of 34 Table 11-1. Callaway Plant Release Category Frequency Results Obtained From SAMA Cases RELEASE CATEGORY FB01 PORV EDGFUEL FW02 SW03 HVAC02 RAI7a SLIS HEP FWCCW2 LERF-IS 1.730E-07 1.730E-07 1.730E-10 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 1.730E-07 LERF-CI 1.658E-10 1.658E-10 1.658E-10 1.658E-10 1.514E-10 1.658E-10 1.658E-10 1.658E-10 1.658E-10 1.567E-10 LERF-CF 1.094E-08 1.112E-08 1.124E-08 1.047E-08 1.031E-08 1.096E-08 1.135E-08 1.123E-08 1.080E-08 1.048E-10 LERF-SG 2.326E-06 2.331E-06 2.331E-06 2.324E-06 2.331E-06 2.331E-06 2.331E-06 2.290E-06 2.329E-06 2.317E-06 LERF-ITR 1.796E-07 2.169E-07 2.169E-07 1.659E-07 2.141E-07 2.169E-07 7.508E-08 2.138E-07 2.170E-07 2.170E-07 LATE-BMT 2.006E-06 2.022E-06 2.544E-06 1.983E-06 2.428E-06 1.990E-06 2.631E-06 2.545E-06 2.523E-06 2.467E-06 LATE-COP 3.185E-06 3.185E-06 3.182E-06 3.185E-06 2.557E-06 2.823E-06 3.235E-06 3.185E-06 3.185E-06 3.174E-06 SERF 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 INTACT 8.146E-06 8.471E-06 8.078E-06 7.796E-06 7.907E-06 8.461E-06 8.119E-06 8.036E-06 7.529E-06 7.311E-06 TOTAL 1.603E-05 1.641E-05 1.636E-05 1.564E-05 1.562E-05 1.601E-05 1.658E-05 1.645E-05 1.597E-05 1.566E-05
ULNRC-05919 October 17, 2012 Page 33 of 34 Table 11-1. Callaway Plant Release Category Frequency Results Obtained From SAMA Cases RELEASE CATEGORY SBOMOD SBOmod2 4kv2 FWCCW LERF-IS 1.730E-07 1.730E-07 1.730E-07 1.730E-07 LERF-CI 1.658E-10 1.658E-10 1.658E-10 1.658E-10 LERF-CF 1.102E-08 1.102E-08 1.124E-10 1.124E-08 LERF-SG 2.331E-06 2.331E-06 2.331E-06 2.331E-06 LERF-ITR 1.628E-07 1.603E-07 2.170E-07 2.170E-07 LATE-BMT 2.485E-06 2.482E-06 2.551E-06 2.551E-06 LATE-COP 2.668E-06 2.642E-06 3.156E-06 3.184E-06 SERF 0.000E+00 0.000E+00 0.000E+00 0.000E+00 INTACT 8.046E-06 8.044E-06 8.080E-06 8.078E-06 TOTAL 1.588E-05 1.584E-05 1.651E-05 1.655E-05
ULNRC-05919 October 17, 2012 Page 34 of 34 RAI 7.b:
SAMA 64 (implement procedure and hardware modifications to allow manual alignment of the fire water system to the component cooling water system, or install a component cooling water header cross-tie) is evaluated by eliminating CCW pump failures. Consider a similar SAMA that provides fire water to the ESW system.
Callaway Response SAMA 64 was revised to evaluate the benefit of a temporary hookup of fire water as backup on loss of CCW cooling to the RHR heat exchangers. This determined the benefit to be $104K with a 95% CDF benefit of $220K. This SAMA is considered potentially cost beneficial and has been added to the list of potentially cost beneficial SAMAs.
SAMA 186 was added to evaluate procedures to provide fire water to the ESW system. This SAMA was considered potentially cost beneficial based on the 95% CDF benefit.
Implementation of this SAMA will cost significantly more than a procedure change since it would require replacement of the existing fire pumps with larger pumps.
FWCCW The CCW fault trees were modified to add fire water as a backup source of cooling to the CCW heat exchangers. The fire water pumps and system do not appear in the PRA. To simulate the use of the fire water pumps and operator actions to perform the temporary hookup, a single basic event with failure probability of 0.1 was placed in the fault trees.
This case is used to evaluate the benefit of providing a temporary hookup of fire water to the CCW heat exchangers.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.