View source for ULNRC-05947, License Renewal Application, Clarification of Responses to SAMA RAIs to the License Renewal Application

{{Adams
| number = ML13016A171
| issue date = 01/15/2013
| title = License Renewal Application, Clarification of Responses to SAMA RAIs to the License Renewal Application
| author name = 
| author affiliation = Ameren Missouri
| addressee name = 
| addressee affiliation = NRC/NRR
| docket = 05000483
| license number = NPF-030
| contact person = 
| case reference number = ULNRC-05947
| package number = ML130160235
| document type = Report, Miscellaneous
| page count = 86
| project = 
| stage = Other
}}

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{{#Wiki_filter:ULNRC-05947 January 15, 2013                                                   Page 1 of 86 CALLAWAY PLANT UNIT 1 LICENSE RENEWAL APPLICATION CLARIFICATION OF RESPONSES TO SAMA RAIs TO THE CALLAWAY LRA

ULNRC-05947 January 15, 2013                                                                            Page 2 of 86
: 1. RAI 1.a The response states that for the new model, consequential loss of offsite power (LOSPs) account for 28 percent of the station blackout (SBO) frequency and only 2.5 percent of the core damage frequency (CDF). This indicates that the benefit from an SBO or LOSP mitigating SAMA should be increased to account for the omission of consequential LOSPs. Also, the impact on other SAMAs of increase in total CDF should be considered. If it is assumed that the likelihood of an SBO is the same for the consequential LOSP as it is for the LOSP initiator, the above indicates that the total SBO frequency (and therefore total LOSP frequency) is approximately 39 percent higher than the frequency due solely to the LOSP initiator alone.
Incorporating this in the Rev. 4B probabilistic risk assessment (PRA) results yields an increase in CDF of 2.17E-06 (39 percent of 5.58E-06) or 13 percent of the SAMA baseline CDF of 1.66E-05. The NRC staff plans to discuss this in the safety evaluation report (SER) and consider these factors in determining the cost-beneficial SAMAs. Based on current information, while several SAMAs are marginally cost-beneficial at the 95th percentile, considering the conservatisms in the assessment, the staff would not consider them to be cost-beneficial. This conclusion could change due to the responses to other requests for clarifications. Clarify this information.
Callaway Response This request was clarified during the call, no further response is necessary. See Reference 4.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                             Page 3 of 86
: 2. RAI 2.d The response does not provide a response to the last portion of the RAI which states:
         "Also, if the source terms for each release category are not bounding, then provide justification of how the impact of higher source term sequences are accounted for in determining the benefit of potential SAMAs, or provide a sensitivity analysis using bounding case source terms."
While the response indicates that both likelihood and potential offsite effects were considered for large early release frequency (LERF) categories, no details are provided, and further, for other release categories, the most likely sequence was chosen. Provide further justification that the source terms selected provide an adequate analysis of the benefit of each SAMA.
Callaway Response The representative sequences for each LERF release category considered both the likelihood and consequences, while each non-LERF release category utilized the most likely contributors.
For all release categories, the dominant Level 1 and Level 2 sequences were identified and considered down to at least a 10% contribution, sometimes less. Based on engineering judgment, none of these dominant sequences were expected to increase the consequences more than the chosen representative sequence. More severe (bounding) scenarios could have been considered, but would have a much lower frequency (at most a 10% contribution).
Therefore, for all release categories, sequences that could have had higher consequences would have much lower frequencies, and therefore not be expected to have a great effect on the SAMA results. There are no specific sensitivity runs that use truly bounding consequences for every release category.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                                Page 4 of 86
: 3. RAI 5.a The response provides a description of NFPA 805 FPRA results in terms of important fire areas, scenarios and modifications identified in the 805 transition LAR. The 805 LAR modifications were included as SAMAs and considered cost-beneficial. No other fire related SAMAs were considered. It is not clear if the 805 FPRA results were reviewed to determine if there would be any further modifications that might be cost-beneficial. Provide the core damage frequency of the important fire scenarios from the NFPA FPRA. Also provide a discussion of the potential for cost-beneficial mitigation of the risk of the important fire areas and/or fire scenarios considering their contribution to the total Callaway CDF.
Callaway Response There was no formal review for SAMAs beyond the identified modifications. The NFPA-805 fire PRA was not completed at the time the SAMA analysis was performed. The fire PRA team position was that no other items should be considered under the NFPA-805 transition process, although this was not performed as a formal SAMA assessment. The Level 2 and Level 3 PRA models used to determine the benefits of SAMA items are based on PRA Update 4b. They cannot interface with the new Fire PRA without extensive modification and analysis. In addition, the NFPA-805 fire PRA is still undergoing changes due to additional plant modifications being installed.
The current Callaway fire PRA results show 14 fire scenarios that are individually greater than 1% of Fire CDF. These scenarios are listed in Enclosure 2, Table 1.
These 14 scenarios make up approximately 56% of the total fire CDF and 7 of the 14 scenarios are dominated by RCP seal LOCA with additional contributions from seal LOCA in several other scenarios. Callaway is scheduled to install the SHIELDTM (no-leakage) RCP seals (SAMA 58) in Refueling Outage 19 (RF19), Spring 2013, which will address a large percentage of the fire risk significant scenarios. In addition, the risk profile will be so significantly changed that it is not warranted to evaluate any further changes until the PRA modeling for the SHIELDTM seals is completed following RF19.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                                Page 5 of 86
: 4. RAI 5.b While the response states:
         "The 1999 internal flooding analysis used as a basis for the SAMA identified only one flood that was below the screening value used. After implementation of the internal flooding task force recommendations, this flood was considered an acceptable risk and no further actions were needed."
it does not discuss if the results of current internal flooding analysis were reviewed to identify potential cost-beneficial SAMAs. The Update 5 internal flooding analysis CDF of 6.21E-06 is sufficiently large that cost-beneficial SAMAs for important flood sequences are possible.
Mitigating an internal flood scenario that has a CDF of approximately 1.1E-06, or 18% of the new internal flood total CDF, would be cost-beneficial at the 95th percentile at the minimum hardware cost of $100,000. A flood scenario with a CDF of 1.8E-07, or 2.8% of the new internal flood CDF, would be cost-beneficial at the minimum procedure cost of $15,000. Provide the CDF of the important internal flooding scenarios or sequences from the Update 5 internal flooding analysis and a discussion of the potential for their cost-beneficial mitigation considering their contribution to the total Callaway CDF.
Callaway Response The Update 5 Internal Flooding analysis was not reviewed in detail to identify potential cost-beneficial SAMAs. This flooding analysis was not available at the time the SAMA analysis was performed. The Update 5 Internal Flooding analysis is based on a significantly different PRA model than the model used to calculate the SAMA benefits. In order to determine benefits from the Update 5 PRA, the full Level 2 PRA model and Level 3 PRA models would require extensive modification.
The current Callaway Internal Flooding analysis results show 17 flooding scenarios that are greater than 1% of Flooding CDF. These scenarios are listed in Enclosure 2, Table 2.
These 17 scenarios make up approximately 70% of the total internal flooding CDF, some of which are primarily seal LOCA events with additional seal LOCA impact in other scenarios.
Although no formal SAMA exists specifically for seal LOCA flood zones, original SAMA 58 is applicable. Callaway is scheduled to install the SHIELDTM (no-leakage) RCP seals in Refueling Outage 19 (RF19), Spring 2013, which will address associated internal flooding scenarios. The risk profile will be changed to the extent that it is not warranted to evaluate any further changes until the PRA modeling for the SHIELDTM seals is completed following RF19.
SAMA 160, modification to change the impact of flooding through the Control Building dumbwaiter, was added while the internal flooding analysis was still being performed.
Personnel participating in the internal flooding analysis had identified this flood path as potentially risk significant and having a low cost of implementation. These personnel also participated in the SAMA Expert Panel Review and added this item to the list of SAMAs.
Analysis is currently underway to determine a more realistic flood height capability for certain plant doors affecting internal flooding. It would limit flood propagation if the evaluation shows the doors are currently capable of higher flood heights or if these doors could be modified to increase their capability to a certain critical flood height. The results of the analysis will be

ULNRC-05947 January 15, 2013                                                                          Page 6 of 86 considered for implementation as potentially cost-beneficial. This analysis has been added as SAMA 189. This SAMA is considered potentially cost-beneficial due to management having directed that the analysis proceed. Tables 5-1, 6-1, 7-1, 8-1, and 9-1 have been updated to include SAMA 189. These updated tables are included at the end of this enclosure.
In addition to these specific flooding SAMA items, numerous SAMA items generically address loss of equipment impacted by floods in the flood zones listed in Enclosure 2, Table 2.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                          Page 7 of 86
: 5. RAI 6.c A new SBO value of 7.85E-07 compared to the earlier (and repeated value in the response to 1.a) of 4.71E-06 is given. Neither is consistent with that inferred from SAMA 2 Case NOSBO of 2.0E-06 (12% of 1.66E-05). The elimination of SBO sequences from the SAMA model resulting from Case NOSBO should have the same percent reduction in CDF as the SBO contribution to the total SAMA model CDF. If the SBO of 7.85E-07 is correct this is 4.73 % compared to the Case 2 result of 12.1%. Provide an explanation of why the Case NOSBO reduction in CDF is different from the correct SBO contribution to the total CDF.
Callaway Response The original case NOSBO (2.0E-06/yr) considered only failures of the diesel generators. The case did not consider failure of the diesel generators due to support systems. This caused Case NOSBO to underestimate the potential benefit of elimination of all EDG failures. However, this case also did not consider recovery of AC power from the Alternate Emergency Power System (AEPS) given failure of the onsite diesel generators. Thus, this case represented failures of the EDGs and sequences initially recovered by power from AEPS. In a large percentage of the cases loss of onsite AC power is recovered through the AEPS, and so this had an appreciable impact on the results. The SBO related CDF of 7.85E-07/yr represents failure of the EDGs, including those from EDG support systems, without sequences where power is recovered from AEPS.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                           Page 8 of 86
: 6. RAI 7.b The revised response indicated that the evaluation of SAMA 186, to evaluate procedures to provide fire water to the ESW system, was changed from SW02 (no failure of ESW pumps) to FWCCW (add fire water as a backup source of cooling to the CCW heat exchangers) and resulted in a decrease in benefit from $635K to $1K). It would appear that SW02 better represents the benefit of this SAMA. Justify the selection of Case FWCCW.
Callaway Response Case SW02 applies to all loads supplied by ESW, including the EDGs, not just the CCW heat exchangers. Emergency procedures are already in place to provide backup cooling to the EDGs using onsite fire trucks in the event that ESW cooling is lost. Case FWCCW evaluates the specific benefit of providing fire water for cooling only the CCW system heat exchangers.
This is because SAMA 186 was intended to evaluate providing backup cooling to only the CCW heat exchanger loads.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                             Page 9 of 86
: 7. RAI 1.a
: i. The SBO value given of 4.71E-6 is different from that given in the response to 6.c of 7.85E-07, which states that the earlier value in incorrect. Provide the correct value for the frequency of total loss of AC power to the station. (See also the question concerning RAI 6.c above.)
ii. In the last sentence of the response, clarify whether or not the internal flood induced ATWS and SBO sequences are included in the ATWS (3.14E-7) and SBO (4.71 E-6) values quoted earlier in the response.
Callaway Response
: i. The 4.71E-6/yr value included in the response to 1.a included sequences where AC power was recovered from the Alternate Emergency Power System (AEPS). The correct CDF value for total loss of AC power is 7.85E-07/yr.
ii. The frequencies of the internal flood induced ATWS and SBO sequences are included in the total internal flood CDF but are not included in the ATWS (3.14E-7) and SBO (7.85E-
: 07) values.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                               Page 10 of 86
: 8. RAI 6.d Case FW02 eliminates failure of all feedwater (FW) check valves and had a CDF reduction of 5.5 percent. Common cause (CC) failure of the 4 main feedwater (MFW) check valves (AEV 120 -123) is listed along with failures of individual valves. Not listed is CC failure of 4 check valves (AEV 124 -127) from motor-driven auxiliary feedwater (MDAFW). Results of the importance analysis appear to indicate that this later failure was included in this case since it gives the 5.5 percent results. Clarify this information.
Callaway Response Case FW02 included the individual and common cause failures of valves AEV 124-127 in addition to AEV 120-123.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                             Page 11 of 86
: 9. RAI 6.g The response states that:
         "For SAMAs 1, 2, and 5 in addition to the TDAFW pump dependency, loss of DC impacts the availability of instrumentation. Emergency Coordinator Supplemental Guidelines exist for the use of portable generators to provide backup power on extended SBO events. This backup portable power is not credited in the PRA."
It is not clear that the availability of this backup source of power and these guidelines would reduce the benefit of SAMA 5, DC bus cross-ties, revised to include the impact on instrumentation, to such an extent that this SAMA would not be cost-beneficial. Provide a discussion of the impact on the benefit for SAMA 5 of including the mitigation of the loss of DC instrumentation and a further justification for the evaluation of SAMA 5.
Callaway Response The instrumentation powered by DC power is not directly modeled in the PRA. The procedural guidance in the Emergency Coordinator supplemental guidelines provides for installation of a portable generator to provide power to the battery charges. This provides a greater benefit than a cross-tie to another battery. A battery cross-tie only extends the availability of the DC bus until the second battery depletes. Use of a portable generator provides DC power availability as long as fuel is available for the generator. Callaway is currently developing additional guidance on the prolonged use of portable generators as part of the post Fukushima response. Use of the generator provides a greater benefit in prolonged SBO conditions that would deplete both the primary and the cross-tied battery.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                              Page 12 of 86
: 10. RAI 6.q Relative to RCP seal modeling and a SAMA to use improved seals, Case RCPLOCA gives a 5.5% reduction in CDF for SAMAs 55, 56 and 58. This seems low compared to that for other plants and it should be different for both SAMAs 55 which includes a dedicated diesel and therefore mitigates RCP seal LOCAs for an SBO and SAMA 58 which is for new improved seals which should also be beneficial for SBOs then for SAMA 56 which doesn't mitigate against an SBO. The response to RAI 6.q says this case eliminates all RCP seal LOCA events that are caused by failure of seal cooling and injection except those which occur as a result of a support system initiating event such as loss of CCW. The Loss of CCW and Loss of SW add up to 1.4%
of the CDF. Is mitigation of RCP seal failure due loss of AC power (SBO) considered in the case? If not, justify this approach and assess the impact on the benefit of these SAMAs.
Callaway Response The existence of the AEPS and the non-safety auxiliary feedwater pump reduced the risk associated with RCP seal failures. The additional AC power source and cooling ability provided by these modifications already reduce the probability of RCP seal failure and thus the relative reduction in overall risk due to elimination of seal LOCAs is not as significant as it is for plants that do not have these modifications installed.
In addition, the modeling of case RCPLOCA was examined in more detail. It was determined that this case did not include those RCP seal LOCA events that were hard coded in the event tree logic. The original case included RCP seal failures due to LOSP and SBO, but did not include seal failures due to loss of CCW or loss of all service water initiating events. No re-evaluation of this case was performed since Callaway is scheduled to install the SHIELDTM (no-leakage) RCP seals in RF19, Spring 2013, which will address a large percentage of the risk due to failure of RCP seals. In addition, the risk profile will be so significantly changed that it is not warranted to evaluate any further changes until the PRA modeling for the SHIELDTM seals is completed following RF19.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                            Page 13 of 86
: 11. RAI Table 7-1 A number of the percent reductions in offsite dose risk in Table 7-1 are given as 0.00%. Does this mean that there is no reduction (i.e. zero) or that it is less than 0.005%? For several cases where 0.00% is given we believe that 0.00% is in error. Please provide the necessary corrections.
Callaway Response All values for offsite dose reduction that are shown in the Table 7-1 as 0.00% are actually less than 0.005%; the rounding to two decimal places causes them to be displayed as 0.00%
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                          Page 14 of 86
: 12. RAI 5.d The Oct. 18 revised response to this RAI indicated that automating the initiation of CCW flow to the RHR heat exchangers was now considered cost-beneficial with a 95th percentile benefit of
$132K and a cost of $200K. Explain.
Callaway Response During the expert panel discussion of this item, it was noted that Wolf Creek had implemented this modification and felt it to be beneficial. Even though the estimated cost was greater than the calculated benefit, Callaway management believes it to be beneficial in areas outside the SAMA and thus close enough to be considered potentially cost beneficial.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                       Page 15 of 86
: 13. RAI 6.j The response provides a description of SAMA Case LOCA 12 used to evaluate SAMAs 25, 26, and 39 which include passive or independently powered injection systems. The calculated benefit does not include that associated with loss of AC power. This would appear to be non-conservative for at least those SAMAs which do not rely on AC power. Discuss the impact of this non-conservatism.
Callaway Response The original LOCA12 case considered only the failures of the HPI and charging pumps and did not consider the loss of AC power which would be mitigated by SAMA items which provided independent AC power. This case was revised to modify the fault trees for the HPI pumps and charging pumps to remove the dependencies on AC power, room cooling, and cooling water from those pumps. The revised case results in a 22.61% reduction in Offsite Economic Cost Risk (OECR). With a benefit of $616K and a 95% CDF benefit of $1.3M, SAMAs 25, 26, and 39 are still considered not cost-beneficial.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                             Page 16 of 86
: 14. RAI 7.a
: i. The discussion of Wolf Creek SAMAs 1 and 14 indicate that the AEPS has a spare breaker that could be used to supply the loads in these SAMAs. Our understanding is that credit for the AEPS to supply plant loads is already included in the Callaway PRA and thus what is included in new Callaway SAMAs 187 and 188 and the resulting benefit is not clear. The analysis cases used to evaluate these SAMAs (SBOMOD and SBOMOD2) both reduce the SBO frequency due to the benefit of the added availability of AC power to certain equipment. Depending on the function of the AEPS and the definition of SBO, it is possible that if credit for the AEPS is already given it must have failed in order for there to be an SBO. Explain the credit for AEPS, the description of these SAMAs and the benefit calculation.
ii. In the discussion of Wolf Creek SAMA 3, Case 4KV, used to evaluate the benefit of revised SAMA 11 (to prepare procedures for using existing equipment to cross-tie 4kV busses), is described as resolving SBO sequences assuming a 0.05 failure rate for the cross-tie then removing this failure event from cutsets involving failure of both emergency diesel generators. Exactly what this accomplished is not clear since all SBO sequences must involve failure of both emergency diesel generators (EDGs). Clarify this information.
Callaway Response
: i. The PRA contains modeling for AEPS to supply those plant loads that are capable of obtaining power from AEPS. Not all plant equipment is able to obtain power from AEPS.
Implementing these SAMAs by the installation of an additional diesel generator were shown to not be cost beneficial. Plant personnel proposed using the spare AEPS supply circuit breaker as a lower cost alternative of accomplishing a similar function. The use of the spare AEPS supply circuit breaker is considered to be potentially cost beneficial.
ii. This SAMA case was revised. This case first generated a fault tree reflecting loss of offsite power conditions along with the major component failure combinations that would fail both EDGs or both ESW trains. This fault tree was quantified and the resultant cutsets were removed from the total internal events core damage, LERF, and Late release cutset equations. The resulting files included those core damage cutsets where consideration of an AC bus cross-tie might reasonably provide some benefit.
The total internal events core damage frequency is 1.655E-05/yr. Removal of loss of offsite power cutsets where both EDGs or both ESW trains fail results in a core damage frequency of 1.264E-05/yr.
It was assumed that an AC bus cross-tie would have a failure probability on the order of 5.0E-02. This factor was applied to all remaining cutsets which included failure of an EDG. This resulted in a final core damage frequency of 1.225E-05/yr.
The benefit due to addition on an AC bus cross-tie would therefore be approximately 3.9E-07/yr (1.264E 1.225E-05). This equates to a benefit of $75K with a 95%

ULNRC-05947 January 15, 2013                                                                       Page 17 of 86 uncertainty benefit of $159K. Based on Wolf Creeks estimated implementation cost of
      $330K, installation of an AC power cross-tie would not be cost beneficial.
Corresponding Amendment Changes No changes to the License Renewal Application (LRA) are needed as a result of this response.

ULNRC-05947 January 15, 2013                                                                                                                      Page 18 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                            Potential Improvement                                                  Discussion                                  Source SAMA Number Extended DC power availability during an SBO station 1     Provide additional DC battery capacity.                                                                                            AC/DC     1 blackout (SBO).
2     Replace lead-acid batteries with fuel cells.                           Extended DC power availability during an SBO.               AC/DC     1 Add additional battery charger or portable, diesel-driven battery 3                                                                            Improved availability of DC power system.                   AC/DC     1 charger to existing DC system.
4     Improve DC bus load shedding.                                          Extended DC power availability during an SBO.               AC/DC     1 5     Provide DC bus cross-ties.                                             Improved availability of DC power system.                   AC/DC     1 6     Provide additional DC power to the 120/240V vital AC system.           Increased availability of the 120 V vital AC bus.           AC/DC     1 Add an automatic feature to transfer the 120V vital AC bus from 7                                                                            Increased availability of the 120 V vital AC bus.           AC/DC     1 normal to standby power.
Increase training on response to loss of two 120V AC buses which       Improved chances of successful response to loss of two 8                                                                                                                                        AC/DC     1 causes inadvertent actuation signals.                                  120V AC buses.
9     Provide an additional diesel generator.                                Increased availability of on-site emergency AC power.       AC/DC     1 10     Revise procedure to allow bypass of diesel generator trips.            Extended diesel generator operation.                        AC/DC     1 11     Improve 4.16-kV bus cross-tie ability.                                 Increased availability of on-site AC power.                 AC/DC     1 12     Create AC power cross-tie capability with other unit (multi-unit site) Increased availability of on-site AC power.                 AC/DC     1 13     Install an additional, buried off-site power source.                   Reduced probability of loss of off-site power.              AC/DC     1 14     Install a gas turbine generator.                                       Increased availability of on-site AC power.                 AC/DC     1 15     Install tornado protection on gas turbine generator.                   Increased availability of on-site AC power.                 AC/DC     1 Increased availability of power supplies supporting front-16     Improve uninterruptible power supplies.                                                                                            AC/DC     1 line equipment.
17     Create a cross-tie for diesel fuel oil (multi-unit site).              Increased diesel generator availability.                    AC/DC     1 18     Develop procedures for replenishing diesel fuel oil.                   Increased diesel generator availability.                    AC/DC     1 19     Use fire water system as a backup source for diesel cooling.           Increased diesel generator availability.                    AC/DC     1 Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                       Page 19 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                            Potential Improvement                                                  Discussion                                   Source SAMA Number 20     Add a new backup source of diesel cooling.                              Increased diesel generator availability.                    AC/DC     1 Increased probability of recovery from failure of breakers 21     Develop procedures to repair or replace failed 4 KV breakers.           that transfer 4.16 kV non-emergency buses from unit         AC/DC     1 station service transformers.
In training, emphasize steps in recovery of off-site power after an     Reduced human error probability during off-site power 22                                                                                                                                         AC/DC     1 SBO.                                                                    recovery.
Improved off-site power recovery following external 23     Develop a severe weather conditions procedure.                                                                                      AC/DC     1 weather-related events.
Improved off-site power reliability during severe 24     Bury off-site power lines.                                                                                                          AC/DC     1 weather.
Install an independent active or passive high pressure injection                                                                     Core 25                                                                             Improved prevention of core melt sequences.                           1 system.                                                                                                                             Cooling Provide an additional high pressure injection pump with independent Reduced frequency of core melt from small LOCA and               Core 26                                                                                                                                                   1 diesel.                                                                 SBO sequences.                                              Cooling Revise procedure to allow operators to inhibit automatic vessel                                                                      Core 27                                                                             Extended HPCI and RCIC operation.                                     1 depressurization in non-ATWS scenarios.                                                                                             Cooling Core 28     Add a diverse low pressure injection system.                            Improved injection capability.                                        1 Cooling Core 29     Provide capability for alternate injection via diesel-driven fire pump. Improved injection capability.                                        1 Cooling Core 30     Improve ECCS suction strainers.                                         Enhanced reliability of ECCS suction.                                 1 Cooling Add the ability to manually align emergency core cooling system                                                                      Core 31                                                                             Enhanced reliability of ECCS suction.                                 1 recirculation.                                                                                                                      Cooling Add the ability to automatically align emergency core cooling system                                                                 Core 32                                                                             Enhanced reliability of ECCS suction.                                 1 to recirculation mode upon refueling water storage tank depletion.                                                                  Cooling Extended reactor water storage tank capacity in the Provide hardware and procedure to refill the reactor water storage                                                                   Core 33                                                                             event of a steam generator tube rupture (or other                     1 tank once it reaches a specified low level.                                                                                         Cooling LOCAs challenging RWST capacity).
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                    Page 20 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                            Potential Improvement                                                 Discussion                                Source SAMA Number Continuous source of water to the safety injection pumps during a LOCA event, since water released from a breach of the primary system collects in the in-          Core 34     Provide an in-containment reactor water storage tank.                                                                                     1 containment reactor water storage tank, and thereby        Cooling eliminates the need to realign the safety injection pumps for long-term post-LOCA recirculation.
Throttle low pressure injection pumps earlier in medium or large-                                                                Core 35                                                                          Extended reactor water storage tank capacity.                        1 break LOCAs to maintain reactor water storage tank inventory.                                                                   Cooling Reduced human error probability associated with             Core 36     Emphasize timely recirculation alignment in operator training.                                                                            1 recirculation failure.                                     Cooling For a plant like the Westinghouse AP600, where the Upgrade the chemical and volume control system to mitigate small     chemical and volume control system cannot mitigate a        Core 37                                                                                                                                               1 LOCAs.                                                               small LOCA, an upgrade would decrease the frequency        Cooling of core damage.
Change the in-containment reactor water storage tank suction from                                                                Core 38                                                                          Reduced common mode failure of injection paths.                      1 four check valves to two check and two air-operated valves.                                                                     Cooling Reduced common cause failure of the safety injection system. This SAMA was originally intended for the Replace two of the four electric safety injection pumps with diesel-                                                             Core 39                                                                          Westinghouse-CE System 80+, which has four trains of                 1 powered pumps.                                                                                                                  Cooling safety injection. However, the intent of this SAMA is to provide diversity within the high- and l Improved chance of successful operation during station Provide capability for remote, manual operation of secondary side                                                                Core 40                                                                          blackout events in which high area temperatures may be               1 pilot-operated relief valves in a station blackout.                                                                             Cooling encountered (no ventilation to main steam areas).
Allows low pressure emergency core cooling system Core 41     Create a reactor coolant depressurization system.                    injection in the event of small LOCA and high-pressure               1 Cooling safety injection failure.
Allows low pressure emergency core cooling system Make procedure changes for reactor coolant system                                                                                Core 42                                                                          injection in the event of small LOCA and high-pressure               1 depressurization.                                                                                                               Cooling safety injection failure.
Cooling 43     Add redundant DC control power for SW pumps.                         Increased availability of SW.                                        1 Water Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                   Page 21 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                             Potential Improvement                                               Discussion                                 Source SAMA Number Elimination of ECCS dependency on component cooling        Cooling 44     Replace ECCS pump motors with air-cooled motors.                                                                                          1 system.                                                    Water Enhance procedural guidance for use of cross-tied component          Reduced frequency of loss of component cooling water       Cooling 45                                                                                                                                               1 cooling or service water pumps.                                      and service water.                                         Water Cooling 46     Add a service water pump.                                            Increased availability of cooling water.                             1 Water Reduced potential for loss of SW due to clogging of        Cooling 47     Enhance the screen wash system.                                                                                                           1 screens.                                                   Water Reduced frequency of loss of component cooling water Cap downstream piping of normally closed component cooling water initiating events, some of which can be attributed to          Cooling 48                                                                                                                                               1 drain and vent valves.                                               catastrophic failure of one of the many single isolation   Water valves.
Enhance loss of component cooling water (or loss of service water)   Reduced potential for reactor coolant pump seal            Cooling 49                                                                                                                                               1 procedures to facilitate stopping the reactor coolant pumps.         damage due to pump bearing failure.                        Water Enhance loss of component cooling water procedure to underscore Cooling 50     the desirability of cooling down the reactor coolant system prior to Reduced probability of reactor coolant pump seal failure.            1 Water seal LOCA.
Improved success of operator actions after a loss of       Cooling 51     Additional training on loss of component cooling water.                                                                                   1 component cooling water.                                   Water Reduced effect of loss of component cooling water by Provide hardware connections to allow another essential raw cooling                                                             Cooling 52                                                                          providing a means to maintain the charging pump seal                 1 water system to cool charging pump seals.                                                                                       Water injection following a loss of normal cooling water.
On loss of essential raw cooling water, proceduralize shedding       Increased time before loss of component cooling water Cooling 53     component cooling water loads to extend the component cooling        (and reactor coolant pump seal failure) during loss of               1 Water water heat-up time.                                                  essential raw cooling water sequences.
Increased time before charging pump failure due to lube    Cooling 54     Increase charging pump lube oil capacity.                                                                                                 1 oil overheating in loss of cooling water sequences.        Water Reduced frequency of core damage from loss of Install an independent reactor coolant pump seal injection system,                                                              Cooling 55                                                                          component cooling water, service water, or station                   1 with dedicated diesel.                                                                                                           Water blackout.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                     Page 22 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                             Potential Improvement                                                Discussion                                   Source SAMA Number Reduced frequency of core damage from loss of Install an independent reactor coolant pump seal injection system,                                                               Cooling 56                                                                          component cooling water or service water, but not a                    1 without dedicated diesel.                                                                                                         Water station blackout.
Reduced frequency of core damage from loss of component cooling water or service water, but not a        Cooling 57    Use existing hydro test pump for reactor coolant pump seal injection.                                                                        1 station blackout, unless an alternate power source is       Water used.
Cooling 58    Install improved reactor coolant pump seals.                          Reduced likelihood of reactor coolant pump seal LOCA.                  1 Water Reduced likelihood of loss of component cooling water      Cooling 59    Install an additional component cooling water pump.                                                                                          1 leading to a reactor coolant pump seal LOCA.                Water Reduced frequency of loss of reactor coolant pump seal cooling if spurious high pressure injection relief valve   Cooling 60    Prevent makeup pump flow diversion through the relief valves.                                                                                1 opening creates a flow diversion large enough to            Water prevent reactor coolant pump seal injection.
Change procedures to isolate reactor coolant pump seal return flow Reduced frequency of core damage due to loss of seal       Cooling 61    on loss of component cooling water, and provide (or enhance)                                                                                 1 cooling.                                                    Water guidance on loss of injection during seal LOCA.
Implement procedures to stagger high pressure safety injection        Extended high pressure injection prior to overheating      Cooling 62                                                                                                                                                 1 pump use after a loss of service water.                               following a loss of service water.                          Water Use fire prevention system pumps as a backup seal injection and                                                                  Cooling fa63                                                                         Reduced frequency of reactor coolant pump seal LOCA.                   1 high pressure makeup source.                                                                                                      Water Implement procedure and hardware modifications to allow manual Improved ability to cool residual heat removal heat        Cooling 64    alignment of the fire water system to the component cooling water                                                                            1 exchangers.                                                 Water system, or install a component cooling water header cross-tie.
Reduced chance of loss of main feed water following a    Feedwater/C 65    Install a digital feed water upgrade.                                                                                                        1 plant trip.                                               ondensate Create ability for emergency connection of existing or new water                                                               Feedwater/C 66                                                                          Increased availability of feedwater.                                   1 sources to feedwater and condensate systems.                                                                                    ondensate Install an independent diesel for the condensate storage tank                                                                  Feedwater/C 67                                                                          Extended inventory in CST during an SBO.                               1 makeup pumps.                                                                                                                   ondensate Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                       Page 23 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                            Potential Improvement                                                  Discussion                                       Source SAMA Number Feedwater/C 68     Add a motor-driven feedwater pump.                                    Increased availability of feedwater.                                        1 ondensate Install manual isolation valves around auxiliary feedwater turbine-   Reduced dual turbine-driven pump maintenance                  Feedwater/C 69                                                                                                                                                       1 driven steam admission valves.                                        unavailability.                                                ondensate Eliminates the need for local manual action to align Install accumulators for turbine-driven auxiliary feedwater pump flow                                                               Feedwater/C 70                                                                           nitrogen bottles for control air following a loss of off-site               1 control valves.                                                                                                                      ondensate power.
Install a new condensate storage tank (auxiliary feedwater storage                                                                  Feedwater/C 71                                                                           Increased availability of the auxiliary feedwater system.                   1 tank).                                                                                                                               ondensate Feedwater/C 72     Modify the turbine-driven auxiliary feedwater pump to be self-cooled. Improved success probability during a station blackout.                     1 ondensate Extended auxiliary feedwater availability during a station Proceduralize local manual operation of auxiliary feedwater system    blackout. Also provides a success path should auxiliary Feedwater/C 73                                                                                                                                                       1 when control power is lost.                                           feedwater control power be lost in non-station blackout        ondensate sequences.
Provide hookup for portable generators to power the turbine-driven                                                                  Feedwater/C 74                                                                           Extended auxiliary feedwater availability.                                  1 auxiliary feedwater pump after station batteries are depleted.                                                                       ondensate Feedwater/C 75     Use fire water system as a backup for steam generator inventory.      Increased availability of steam generator water supply.                     1 ondensate Allows greater inventory for the auxiliary feedwater Change failure position of condenser makeup valve if the condenser                                                                  Feedwater/C 76                                                                           pumps by preventing condensate storage tank flow                            1 makeup valve fails open on loss of air or power.                                                                                     ondensate diversion to the condenser.
Provide a passive, secondary-side heat-rejection loop consisting of a Reduced potential for core damage due to loss-of-             Feedwater/C 77                                                                                                                                                       1 condenser and heat sink.                                              feedwater events.                                              ondensate Modify the startup feedwater pump so that it can be used as a Feedwater/C 78     backup to the emergency feedwater system, including during a          Increased reliability of decay heat removal.                                1 ondensate station blackout scenario.
Replace existing pilot-operated relief valves with larger ones, such                                                                Feedwater/C 79                                                                           Increased probability of successful feed and bleed.                         1 that only one is required for successful feed and bleed.                                                                             ondensate Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                        Page 24 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                             Potential Improvement                                                  Discussion                                       Source SAMA Number Increased availability of components dependent on 80     Provide a redundant train or means of ventilation.                                                                                      HVAC       1 room cooling.
Add a diesel building high temperature alarm or redundant louver 81                                                                             Improved diagnosis of a loss of diesel building HVAC.           HVAC       1 and thermostat.
Increased availability of ventilation in the event of a loss 82     Stage backup fans in switchgear rooms.                                                                                                  HVAC       1 of switchgear ventilation.
83     Add a switchgear room high temperature alarm.                           Improved diagnosis of a loss of switchgear HVAC.                HVAC       1 Create ability to switch emergency feedwater room fan power supply 84                                                                             Continued fan operation in a station blackout.                  HVAC       1 to station batteries in a station blackout.
Provide cross-unit connection of uninterruptible compressed air         Increased ability to vent containment using the 85                                                                                                                                          IA/Nitrogen   1 supply.                                                                 hardened vent.
Modify procedure to provide ability to align diesel power to more air 86                                                                             Increased availability of instrument air after a LOOP.       IA/Nitrogen   1 compressors.
Replace service and instrument air compressors with more reliable Elimination of instrument air system dependence on 87     compressors which have self-contained air cooling by shaft driven                                                                    IA/Nitrogen   1 service water cooling.
fans.
88     Install nitrogen bottles as backup gas supply for safety relief valves. Extended SRV operation time.                                 IA/Nitrogen   1 89     Improve SRV and MSIV pneumatic components.                              Improved availability of SRVs and MSIVs.                     IA/Nitrogen   1 Enhanced debris cool ability, reduced core concrete          Containment 90     Create a reactor cavity flooding system.                                                                                                           1 interaction, and increased fission product scrubbing.        Phenomena Containment 91     Install a passive containment spray system.                             Improved containment spray capability.                                     1 Phenomena Use the fire water system as a backup source for the containment                                                                     Containment 92                                                                             Improved containment spray capability.                                     1 spray system.                                                                                                                        Phenomena Increased decay heat removal capability for non-ATWS         Containment 93     Install an unfiltered, hardened containment vent.                                                                                                  1 events, without scrubbing released fission products.         Phenomena Install a filtered containment vent to remove decay heat. Option 1:     Increased decay heat removal capability for non-ATWS         Containment 94                                                                                                                                                        1 Gravel Bed Filter; Option 2: Multiple Venturi Scrubber                  events, with scrubbing of released fission products.         Phenomena Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                              Page 25 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                             Potential Improvement                                         Discussion                                     Source SAMA Number Enhance fire protection system and standby gas treatment system                                                           Containment 95                                                                    Improved fission product scrubbing in severe accidents.                 1 hardware and procedures.                                                                                                  Phenomena Reduced likelihood of hydrogen and carbon monoxide        Containment 96    Provide post-accident containment inerting capability.                                                                                  1 gas combustion.                                           Phenomena Increased cooling and containment of molten core debris. Molten core debris escaping from the vessel is Create a large concrete crucible with heat removal potential to                                                           Containment 97                                                                    contained within the crucible and a water cooling                       1 contain molten core debris.                                                                                               Phenomena mechanism cools the molten core in the crucible, preventing melt-through of the base mat.
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 Containment 98    Create a core melt source reduction system.                     material would melt and combine with the material.                      1 Phenomena Subsequent spreading and heat removal from the vitrified compound would be facilitated, and concrete attack would not occur.
Strengthen primary/secondary containment (e.g., add ribbing to                                                            Containment 99                                                                    Reduced probability of containment over-pressurization.                 1 containment shell).                                                                                                       Phenomena Increase depth of the concrete base mat or use an alternate                                                               Containment 100                                                                    Reduced probability of base mat melt-through.                           1 concrete material to ensure melt-through does not occur.                                                                  Phenomena Increased potential to cool a molten core before it Containment 101    Provide a reactor vessel exterior cooling system.               causes vessel failure, by submerging the lower head in                  1 Phenomena water.
Construct a building to be connected to primary/secondary                                                                 Containment 102                                                                    Reduced probability of containment over-pressurization.                 1 containment and maintained at a vacuum.                                                                                   Phenomena Improved arrest of core melt progress and prevention of Containment 103    Institute simulator training for severe accident scenarios.                                                                             1 containment failure.                                      Phenomena Increased piping surveillance to identify leaks prior to Containment 104    Improve leak detection procedures.                              complete failure. Improved leak detection would reduce                  1 Phenomena LOCA frequency.
Containment 105    Delay containment spray actuation after a large LOCA.           Extended reactor water storage tank availability.                       1 Phenomena Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                Page 26 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                            Potential Improvement                                             Discussion                                    Source SAMA Number Extended time over which water remains in the reactor Containment 106    Install automatic containment spray pump header throttle valves. water storage tank, when full containment spray flow is               1 Phenomena not needed.
Containment 107    Install a redundant containment spray system.                       Increased containment heat removal ability.                           1 Phenomena Install an independent power supply to the hydrogen control system using either new batteries, a non-safety grade portable generator,                                                          Containment 108                                                                        Reduced hydrogen detonation potential.                                1 existing station batteries, or existing AC/DC independent power                                                             Phenomena supplies, such as the security system diesel.
Containment 109    Install a passive hydrogen control system.                          Reduced hydrogen detonation potential.                                1 Phenomena Erect a barrier that would provide enhanced protection of the Containment 110    containment walls (shell) from ejected core debris following a core Reduced probability of containment failure.                           1 Phenomena melt scenario at high pressure.
Install additional pressure or leak monitoring instruments for                                                              Containment 111                                                                        Reduced ISLOCA frequency.                                             1 detection of ISLOCAs.                                                                                                         Bypass Add redundant and diverse limit switches to each containment        Reduced frequency of containment isolation failure and  Containment 112                                                                                                                                              1 isolation valve.                                                    ISLOCAs.                                                  Bypass Containment 113    Increase leak testing of valves in ISLOCA paths.                    Reduced ISLOCA frequency.                                             1 Bypass Containment 114    Install self-actuating containment isolation valves.                Reduced frequency of isolation failure.                               1 Bypass Containment 115    Locate residual heat removal (RHR) inside containment               Reduced frequency of ISLOCA outside containment.                      1 Bypass Ensure ISLOCA releases are scrubbed. One method is to plug Containment 116    drains in potential break areas so that break point will be covered Scrubbed ISLOCA releases.                                             1 Bypass with water.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                         Page 27 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                             Potential Improvement                                                  Discussion                                     Source SAMA Number Increased likelihood that LOCAs outside containment are identified as such. A plant had a scenario in which Containment 117    Revise EOPs to improve ISLOCA identification.                           an RHR ISLOCA could direct initial leakage back to the                   1 Bypass pressurizer relief tank, giving indication that the LOCA was inside containment.
Containment 118    Improve operator training on ISLOCA coping.                             Decreased ISLOCA consequences.                                           1 Bypass Institute a maintenance practice to perform a 100% inspection of                                                                   Containment 119                                                                            Reduced frequency of steam generator tube ruptures.                      1 steam generator tubes during each refueling outage.                                                                                  Bypass Containment 120    Replace steam generators with a new design.                             Reduced frequency of steam generator tube ruptures.                      1 Bypass Increase the pressure capacity of the secondary side so that a steam Eliminates release pathway to the environment following Containment 121                                                                                                                                                     1 generator tube rupture would not cause the relief valves to lift.       a steam generator tube rupture.                              Bypass Install a redundant spray system to depressurize the primary system Enhanced depressurization capabilities during steam            Containment 122                                                                                                                                                     1 during a steam generator tube rupture                                   generator tube rupture.                                      Bypass Backup method to using pressurizer sprays to reduce Proceduralize use of pressurizer vent valves during steam generator                                                                Containment 123                                                                            primary system pressure following a steam generator                      1 tube rupture sequences.                                                                                                              Bypass tube rupture.
Provide improved instrumentation to detect steam generator tube                                                                    Containment 124                                                                            Improved mitigation of steam generator tube ruptures.                    1 ruptures, such as Nitrogen-16 monitors).                                                                                             Bypass Route the discharge from the main steam safety valves through a Reduced consequences of a steam generator tube             Containment 125    structure where a water spray would condense the steam and                                                                                       1 rupture.                                                     Bypass remove most of the fission products.
Install a highly reliable (closed loop) steam generator shell-side heat Reduced consequences of a steam generator tube             Containment 126    removal system that relies on natural circulation and stored water                                                                               1 rupture.                                                     Bypass sources Revise emergency operating procedures to direct isolation of a          Reduced consequences of a steam generator tube             Containment 127                                                                                                                                                     1 faulted steam generator.                                                rupture.                                                     Bypass Direct steam generator flooding after a steam generator tube            Improved scrubbing of steam generator tube rupture         Containment 128                                                                                                                                                     1 rupture, prior to core damage.                                          releases.                                                    Bypass Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                      Page 28 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                            Potential Improvement                                                 Discussion                                      Source SAMA Number Reduced consequences of a steam generator tube             Containment 129    Vent main steam safety valves in containment.                                                                                                   1 rupture.                                                     Bypass 130    Add an independent boron injection system.                            Improved availability of boron injection during ATWS.         ATWS        1 Add a system of relief valves to prevent equipment damage from 131                                                                          Improved equipment availability after an ATWS.                ATWS        1 pressure spikes during an ATWS.
132    Provide an additional control system for rod insertion (e.g., AMSAC). Improved redundancy and reduced ATWS frequency.               ATWS        1 Install an ATWS sized filtered containment vent to remove decay       Increased ability to remove reactor heat from ATWS 133                                                                                                                                        ATWS        1 heat.                                                                 events.
Affords operators more time to perform actions.
Discharge of a substantial fraction of steam to the main condenser (i.e., as opposed to into the primary Revise procedure to bypass MSIV isolation in turbine trip ATWS 134                                                                          containment) affords the operator more time to perform        ATWS        1 scenarios.
actions (e.g., SLC injection, lower water level, depressurize RPV) than if the main condenser was unavailable, resulting in lower human error probabilities.
Allows immediate control of low pressure core injection.
On failure of high pressure core injection and Revise procedure to allow override of low pressure core injection 135                                                                          condensate, some plants direct reactor depressurization       ATWS        1 during an ATWS event.
followed by five minutes of automatic low pressure core injection.
136    Install motor generator set trip breakers in control room.            Reduced frequency of core damage due to an ATWS.              ATWS        1 Decreased time required to insert control rods if the Provide capability to remove power from the bus powering the 137                                                                          reactor trip breakers fail (during a loss of feedwater        ATWS        1 control rods.
ATWS which has rapid pressure excursion).
Reduced frequency of internal flooding due to failure of     Internal 138    Improve inspection of rubber expansion joints on main condenser.                                                                                1 circulating water system expansion joints.                   Flooding Modify swing direction of doors separating turbine building basement                                                               Internal 139                                                                          Prevents flood propagation.                                               1 from areas containing safeguards equipment.                                                                                        Flooding Increased availability of necessary plant equipment 140    Increase seismic ruggedness of plant components.                                                                                 Seismic Risk   1 during and after seismic events.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                     Page 29 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                             Potential Improvement                                                Discussion                                    Source SAMA Number Increased availability of fire protection given a seismic 141    Provide additional restraints for CO2 tanks.                                                                                   Seismic Risk   1 event.
Decreased probability of spurious fire suppression 142    Replace mercury switches in fire protection system.                                                                              Fire Risk    1 system actuation.
143    Upgrade fire compartment barriers.                                   Decreased consequences of a fire.                           Fire Risk    1 144    Install additional transfer and isolation switches.                  Reduced number of spurious actuations during a fire.        Fire Risk    1 145    Enhance fire brigade awareness.                                      Decreased consequences of a fire.                           Fire Risk    1 146    Enhance control of combustibles and ignition sources.                Decreased fire frequency and consequences.                  Fire Risk    1 Reduced probability of a large break LOCA (a leak 147    Install digital large break LOCA protection system.                                                                                Other      1 before break).
148    Enhance procedures to mitigate large break LOCA.                     Reduced consequences of a large break LOCA.                   Other      1 Install computer aided instrumentation system to assist the operator Improved prevention of core melt sequences by making 149                                                                                                                                       Other      1 in assessing post-accident plant status.                             operator actions more reliable.
Improved prevention of core melt sequences by 150    Improve maintenance procedures.                                                                                                    Other      1 increasing reliability of important equipment.
Increase training and operating experience feedback to improve       Improved likelihood of success of operator actions taken 151                                                                                                                                       Other      1 operator response.                                                   in response to abnormal conditions.
Reduced consequences of transportation and nearby 152    Develop procedures for transportation and nearby facility accidents.                                                              Other       1 facility accidents.
Prevents secondary side depressurization should a steam line break occur upstream of the main steam Install secondary side guard pipes up to the main steam isolation 153                                                                         isolation valves. Also guards against or prevents            Other       1 valves.
consequential multiple steam generator tube ruptures following a main steam line break event.
Reduces failure probability of MCCs during an               IPEEE -
154    Mount or anchor the MCCs to the respective building walls.                                                                                    B earthquake                                                  Seismic Takes up the shear load on the pump and/or driver           IPEEE -
155    Install shear pins (or strength bolts) in the AFW pumps.                                                                                      B during an earthquake.                                       Seismic Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                      Page 30 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                            Potential Improvement                                                    Discussion                                 Source SAMA Number Mount all fire extinguishers within their UL Standard required drop   Reduces the potential for the fire extinguishers to fall IPEEE -
156    height and remove hand-held fire extinguishers from Containment       during an earthquake and potentially fracturing upon                    B Seismic during normal operation.                                              impact with the floor or another object.
Ensures direct access to areas such as Load Shedding and Emergency Load Sequencing (LSELS) and Identify and remove unsecured equipment near areas that contain       Engineered Safety Feature Actuation                         IPEEE -
157                                                                                                                                                  B relays that actuate, so area is kept clear.                           System (ESFAS) cabinets. Unsecured equipment (e.g.,          Seismic carts, filing cabinets, and test equipment) in these areas could result Improper positioning of hoists reduces the availability Properly position chain hoists that facilitate maintenance on pumps due to moving during an earthquake and having               IPEEE -
158    within pump rooms and institute a training program to ensure that the                                                                         B chainfalls impacting pump oil bubblers or other soft         Seismic hoists are properly positioned when not in use.
targets resulting in failure of the pumps.
Secure floor grating to prevent damage to sensing lines due to        Prevent sensing lines that pass through the grating from    IPEEE -
159                                                                                                                                                  B differential building motion.                                         being damaged.                                               Seismic Modifications to lessen impact of internal flooding path through      Lower impact of flood that propagates through the            Internal 160                                                                                                                                                  D Control Building dumbwaiter.                                          dumbwaiter                                                  Flooding Improvements to PORV performance that will lower the probability of                                                                  Core 161                                                                          Decrease in risk due to PORV failing to open.                           E failure to open.                                                                                                                   Cooling Install a large volume EDG fuel oil tank at an elevation greater than Allows transfer of EDF fuel oil to the EDG day tanks on 162                                                                                                                                       AC/DC      C the EDG fuel oil day tanks.                                           failure of the fuel oil transfer pumps.
Lower risk due to failures in which feedwater check Improve feedwater check valve reliability to reduce probability of                                                                 Cooling 163                                                                          valves fail to open and allow feeding of the steam                      E failure to open.                                                                                                                    Water generators.
Provide the capability to power the normal service water pumps from Provide backup to ESW in conditions with power only            Cooling 164                                                                                                                                                  D AEPS.                                                                 available from AEPS.                                          Water Purchase or manufacture a "gagging device" that could be used to Reduce the amount of radioactive material release to 165    close a stuck open steam generator relief valve for a SGTR event                                                                    SGTR      C the atmosphere in a SGTR event with core damage.
prior to core damage.
RCP Seal 166    Installation of high temperature qualified RCP seal O-rings.          Lower potential for RCP seal leakage.                                   A LOCA Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                    Page 31 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                           Potential Improvement                                                 Discussion                                  Source SAMA Number Addition of procedural guidance to re-establish normal service water                                                            Cooling 167                                                                         Provide back-up pumps for UHS cooling.                                A should essential service water fail.                                                                                             Water Addition of procedural guidance for running charging and safety      Allow use of pumps following loss of component cooling     Cooling 168                                                                                                                                               A injection pumps without component cooling water                      water.                                                      Water Addition of procedural guidance to verify RHR pump room cooling at Verifying that support system for RHR pumps is in 169                                                                                                                                     HVAC      A switchover to ECCS recirculation phase.                              service to allow continued operation of RHR pumps.
Modifications to add controls in the main control room to allow Faster ability to provide power to the plant electrical 170    remote operation of nearby diesel generator farm and                                                                           AC Power    C busses from the offsite diesel generator farm.
alignment/connection to the plant vital electrical busses.
Increase the size of the RWST or otherwise improve the availability  Ensure a supply of makeup water is available from the       Core 171                                                                                                                                               E of the RWST                                                          RWST.                                                      Cooling Addition of procedural guidance and the required hardware to enable 172    the operators to feed one or more steam generators with a diesel     Provide a backup to turbine driven auxiliary feedwater. Feedwater   A driven firewater pump.
A redundant source of AC Power that could be used in 173    Addition of a black start combustion turbine generator.                                                                        AC Power    A station blackout events.
Ability to power a 125VDC battery charger and a charging pump. Powering the battery charger would Addition of a black-start engine-generator to provide AC Power       permit operation of the TDAFP without recovering AC 174                                                                                                                                   AC Power    A during a station blackout                                            power. Powering a charging pump could provide RCP seal injection and preclude a RCP seal LOCA during a station blackout.
Replacement of the positive displacement charging pump with a third Provide another source for RCP seal cooling, RCS            Cooling 175                                                                                                                                               A centrifugal charging pump.                                           makeup, and pumped flow for feed and bleed.                 Water Allow faster and more reliable bypass of the main Provide control modifications to bypass feedwater isolation in order feedwater isolation signal in order to restore main 176                                                                                                                                   Feedwater   A to restore main feedwater.                                           feedwater to the steam generators should auxiliary feedwater fail.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                          Page 32 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                             Potential Improvement                                                     Discussion                                     Source SAMA Number The IPE identified a need to form a task force to identify and evaluate potential procedural and hardware Procedural and hardware modifications to reduce core damage risk           modifications aimed at reducing the risk due to internal 177                                                                                                                                           Flooding     A due to internal flooding.                                                  flooding.
178    Improvements to UHS cooling tower electrical room HVAC.                    Improve availability or mitigate loss of HVAC.               HVAC        E Modify procedures such that the water loop seals in the RCS cold           Prevents possible thermally induced steam generator        Containment 179                                                                                                                                                        C legs are not cleared following core damage.                                tube rupture following core damage.                          Bypass Install lower amperage fuses for various 14 AWG control circuits in 180    the MCR. The majority of the modification centers around the trip          Reduced fire risk.                                          Fire Risk    F circuit fuses on NB, NG, PA, PB, and PG system breakers.
Install redundant fuses and isolation switches for MCR evacuation 181                                                                               Reduced fire risk.                                          Fire Risk    F procedure OTO-ZZ-00001.
To protect against multiple spurious operation scenarios, cable runs will be changed to run a single wire in a protected metal jacket such 182    that spurious valve opening due to a hot short affecting the valve         Reduced fire risk.                                          Fire Risk    F control circuit is eliminated for the fire area. This modification will be implemented in multiple fire areas.
Quick response sprinkler heads in cable chases A-11, C-30, and C-183    31 will be modified to be in accordance with the applicable                Reduced fire risk.                                          Fire Risk    F requirements of NFPA 13-1976 edition.
Improvements in the reliability of the Steam Line Isolation automatic                                                                 Containment 184                                                                               More reliable main steam line isolation.                                 E signal.                                                                                                                                Isolation Cooling 185    Automate initiation of CCW flow to the RHR heat exchangers.                More reliable than manual initiation of flow to RRHR HX.                 E Water Develop a procedure and obtain equipment to provide a temporary            Backup cooling water if ESW/SW is lost                       Cooling 186                                                                                                                                                        D hookup of fire water as a replacement for ESW                                                                                           Water Install modification to power the normal charging pump from an             Another source of backup power to the NCP in cases of        Cooling 187                                                                                                                                                        C existing spare breaker from the AEPS.                                      station blackout or loss of service water                    Water Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                        Page 33 of 86 Table 5-1. List of SAMA Candidates.
Callaway Focus of SAMA                               Potential Improvement                                                   Discussion                                Source SAMA Number Another source of backup power to the NCP, DC power Install a permanent, dedicated generator for the NCP, and a motor-(pump/valve control and SG level instrumentation), and  Cooling 188      driven AFW pump and battery charger to address SBO events in                                                                                 C power to an AFW pump in cases of station blackout or     Water which the TD AFW pump is unavailable.
loss of service water Perform analysis to determine if it is possible to modify current plant doors to withstand higher flood heights. Either perform modifications Internal 189      to install improved doors or revise flooding analysis to incorporate      Reduction in risk due to internal flooding.                        D Flooding results that doors will withstand higher flooding heights without propagating the flood.
Note 1: The source references are:
1    NEI 05-01 (Reference 19)
A    IPE (Reference 28)
B    IPEEE (Reference 29)
C    Recent industry SAMA submittals (Wolf Creek, South Texas, Diablo Canyon, Seabrook)
D    Expert panel convened to review SAMA analysis or other plant personnel E    PRA importance list review F    Callaway NFPA 805 License Amendment Request Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                    Page 34 of 86 6.0    PHASE I ANALYSIS A preliminary screening of the complete list of SAMA candidates was performed to limit the number of SAMAs for which detailed analysis in Phase II was necessary. The screening criteria used in the Phase I analysis are described below.
Screening Criterion A - Not Applicable: If a SAMA candidate did not apply to the Callaway Unit 1 plant design, it was not retained.
Screening Criterion B - Already Implemented or Intent Met: If a SAMA candidate had already been implemented at the Callaway Plant or its intended benefit already achieved by other means, it was not retained.
Screening Criterion C - Combined: If a SAMA candidate was similar in nature and could be combined with another SAMA candidate to develop a more comprehensive or plant-specific SAMA candidate, only the combined SAMA candidate was retained.
Screening Criterion D - Excessive Implementation Cost: If a SAMA required extensive changes that will obviously exceed the maximum benefit (Section 4.5), even without an implementation cost estimate, it was not retained.
Screening Criterion E - Very Low Benefit: If a SAMA from an industry document was related to a non-risk significant system for which change in reliability is known to have negligible impact on the risk profile, it was not retained. (No SAMAs were screened using this criterion.)
Table 6-1 presents the list of Phase I SAMA candidates and provides the disposition of each candidate along with the applicable screening criterion associated with each candidate. Those candidates that have not been screened by application of these criteria are evaluated further in the Phase II analysis (Section 7).
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                Page 35 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA          Potential Improvement                             Discussion                              Screening Criterion       Phase I Disposition Out Ph 1?
Number Create AC power cross-tie 12    capability with other unit (multi-unit Increased availability of on-site AC power.      Yes     A - Not Applicable   Callaway is a single unit site.
site)
Create a cross-tie for diesel fuel oil 17                                           Increased diesel generator availability.         Yes     A - Not Applicable   Callaway is a single unit site.
(multi-unit site).
Revise procedure to allow operators to inhibit automatic 27                                           Extended HPCI and RCIC operation.                Yes     A - Not Applicable   BWR item.
vessel depressurization in non-ATWS scenarios.
Continuous source of water to the safety injection pumps during a LOCA event, since water released from a breach of the primary                                   Not applicable for existing Provide an in-containment reactor 34                                           system collects in the in-containment reactor    Yes     A - Not Applicable   designs. Insufficient room water storage tank.
water storage tank, and thereby eliminates                                    inside primary containment.
the need to realign the safety injection pumps for long-term post-LOCA recirculation.
Per the Callaway safety analysis, this is an Throttle low pressure injection                                                                                      undesirable action. The pumps earlier in medium or large-      Extended reactor water storage tank                                           Callaway safety analysis and 35                                                                                            Yes     A - Not Applicable break LOCAs to maintain reactor        capacity.                                                                     design calls for injection of the water storage tank inventory.                                                                                        RWST to inside the containment as soon as possible.
Change the in-containment reactor Callaway does not have an in-water storage tank suction from        Reduced common mode failure of injection 38                                                                                            Yes     A - Not Applicable   containment RWST with this four check valves to two check and paths.
valve arrangement.
two air-operated valves.
Plant uses Ultimate Heat Sink pond for cooling. UHS sized Reduced potential for loss of SW due to 47    Enhance the screen wash system.                                                         Yes     A - Not Applicable   for 30 days without make-up.
clogging of screens.
River intake is only used for make-up to the UHS.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                             Page 36 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                           Discussion                            Screening Criterion         Phase I Disposition Out Ph 1?
Number Provide hardware connections to      Reduced effect of loss of component cooling                                  Charging pump seals do not allow another essential raw cooling  water by providing a means to maintain the                                   require external cooling, they 52                                                                                         Yes     A - Not Applicable water system to cool charging        charging pump seal injection following a loss                                are cooled by the process pump seals.                          of normal cooling water.                                                     fluid.
Callaway does not have a Reduced frequency of core damage from                                        permanently installed hydro Use existing hydro test pump for     loss of component cooling water or service                                   test pump. Timing 57                                                                                         Yes     A - Not Applicable reactor coolant pump seal injection. water, but not a station blackout, unless an                                 considerations prevent credit alternate power source is used.                                              for hookup of temporary pump.
Existing fire protection system Use fire prevention system pumps Reduced frequency of reactor coolant pump                                    pumps do not have sufficient 63    as a backup seal injection and high                                                  Yes     A - Not Applicable seal LOCA.                                                                   discharge head to use as high pressure makeup source.
pressure makeup source.
Install manual isolation valves Reduced dual turbine-driven pump                                             Callaway does not have dual 69    around auxiliary feedwater turbine-                                                  Yes     A - Not Applicable maintenance unavailability.                                                  turbine AFW pump.
driven steam admission valves.
Provide cross-unit connection of Increased ability to vent containment using 85    uninterruptible compressed air                                                       Yes     A - Not Applicable   N/A, single unit.
the hardened vent.
supply.
Enhance fire protection system and Improved fission product scrubbing in severe                                 Standby gas treatment system 95    standby gas treatment system                                                         Yes     A - Not Applicable accidents.                                                                   is BWR item.
hardware and procedures.
Per the Callaway safety analysis, this is an undesirable action. The Delay containment spray actuation Extended reactor water storage tank                                             Callaway safety analysis and 105                                                                                         Yes     A - Not Applicable after a large LOCA.                  availability.                                                                design calls for injection of the RWST to inside the containment as soon as possible.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                               Page 37 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                            Discussion                             Screening Criterion        Phase I Disposition Out Ph 1?
Number Per the Callaway safety analysis, this is an undesirable action. The Extended time over which water remains in Install automatic containment spray                                                                                 Callaway safety analysis and 106                                        the reactor water storage tank, when full          Yes     A - Not Applicable pump header throttle valves.                                                                                        design calls for injection of the containment spray flow is not needed.
RWST to inside the containment as soon as possible.
Affords operators more time to perform actions. Discharge of a substantial fraction of steam to the main condenser (i.e., as Revise procedure to bypass MSIV     opposed to into the primary containment) 134    isolation in turbine trip ATWS      affords the operator more time to perform          Yes     A - Not Applicable   Specific to BWRs.
scenarios.                          actions (e.g., SLC injection, lower water level, depressurize RPV) than if the main condenser was unavailable, resulting in lower human error probabilities.
Allows immediate control of low pressure core injection. On failure of high pressure Revise procedure to allow override core injection and condensate, some plants                                      Based on description, this is a 135    of low pressure core injection                                                         Yes     A - Not Applicable direct reactor depressurization followed by                                     BWR item.
during an ATWS event.
five minutes of automatic low pressure core injection.
Improve inspection of rubber        Reduced frequency of internal flooding due to                                   No risk significant flooding 138    expansion joints on main            failure of circulating water system expansion      Yes     A - Not Applicable   sources identified in the condenser.                          joints.                                                                         turbine building.
Modify swing direction of doors                                                                                     Flooding analysis did not separating turbine building                                                                                         indicate any flooding issues 139                                        Prevents flood propagation.                        Yes     A - Not Applicable basement from areas containing                                                                                      related to the direction of door safeguards equipment.                                                                                               swing.
Replace mercury switches in fire    Decreased probability of spurious fire                                          No mercury switches in the 142                                                                                           Yes     A - Not Applicable protection system.                  suppression system actuation.                                                   fire protection system.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                        Page 38 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA          Potential Improvement                          Discussion                         Screening Criterion        Phase I Disposition Out Ph 1?
Number Fire analysis did not identify any issues related to fire barriers. NFPA 805 Fire 143    Upgrade fire compartment barriers. Decreased consequences of a fire.            Yes     A - Not Applicable   Protection Program is in progress, any issues identified by that project will be handled by the NFPA 805 program.
IPEEE determined that there Develop procedures for Reduced consequences of transportation and                                are no transportation routes or 152    transportation and nearby facility                                              Yes     A - Not Applicable nearby facility accidents.                                                nearby facilities that could accidents.
cause concern.
Callaway does not have the ability to isolate the steam Purchase or manufacture a                                                                                    generator from the RCS loop.
         "gagging device" that could be     Reduce the amount of radioactive material                                 The amount of force required 165    used to close a stuck open steam   release to the atmosphere in a SGTR event    Yes     A - Not Applicable   to close a stuck open generator relief valve for a SGTR  with core damage.                                                         atmospheric steam dump event prior to core damage.                                                                                  valve would likely not be successful and would result in further damage to the valve.
Current configuration is two spare battery chargers for the instrument buses. The spare can carry one bus. One feeds Add additional battery charger or A/B, the other feeds C/D 3    portable, diesel-driven battery    Improved availability of DC power system. Yes     B - Intent Met trains. Also Emergency charger to existing DC system.
Coordinator Supplemental Guidelines, Attachment N, "Temporary Power to NK Swing Charger Extended DC power availability during an                                  DC load shedding is 4    Improve DC bus load shedding.                                                   Yes     B - Intent Met SBO.                                                                      conducted.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                              Page 39 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                             Discussion                             Screening Criterion       Phase I Disposition Out Ph 1?
Number Procedures in place to provide Provide additional DC power to the Increased availability of the 120 V vital AC                                     temporary power to DC 6                                                                                            Yes     B - Intent Met 120/240V vital AC system.              bus.                                                                         Chargers which can power vital AC system.
On loss of DC or inverter, the UPS static switch automatically transfers to AC Add an automatic feature to Increased availability of the 120 V vital AC                                 power through a constant 7    transfer the 120V vital AC bus from                                                     Yes     B - Intent Met bus.                                                                         voltage transformer. An normal to standby power.
additional backup AC source is available, but must be closed manually.
Increase training on response to loss of two 120V AC buses which        Improved chances of successful response to                                   Typical response training in 8                                                                                            Yes     B - Intent Met causes inadvertent actuation           loss of two 120V AC buses.                                                   place.
signals.
Provide an additional diesel           Increased availability of on-site emergency                                  Alternate Emergency Power 9                                                                                            Yes     B - Intent Met generator.                             AC power.                                                                    System installed.
Bypass of non-vital diesel Revise procedure to allow bypass 10                                           Extended diesel generator operation.             Yes     B - Intent Met      generator trips were in original of diesel generator trips.
design for Callaway.
Install an additional, buried off-site                                                                              AEPS installed with buried 13                                           Reduced probability of loss of off-site power. Yes     B - Intent Met power source.                                                                                                       power lines.
Alternate Emergency Power 14    Install a gas turbine generator.       Increased availability of on-site AC power.      Yes     B - Intent Met System installed.
Improve uninterruptible power          Increased availability of power supplies                                     Replaced to add static switch 16                                                                                            Yes     B - Intent Met supplies.                              supporting front-line equipment.                                             and upgrade to newer design.
Develop procedures for                                                                                              EOP Addenda direct ordering 18                                           Increased diesel generator availability.         Yes     B - Intent Met replenishing diesel fuel oil.                                                                                       fuel oil.
Use fire water system as a backup                                                                                   Procedures exist for cooling 19                                           Increased diesel generator availability.         Yes     B - Intent Met source for diesel cooling.                                                                                          EDG with fire water.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                             Page 40 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA            Potential Improvement                           Discussion                             Screening Criterion      Phase I Disposition Out Ph 1?
Number Add a new backup source of diesel                                                                                  Procedure exists for backup 20                                          Increased diesel generator availability.         Yes     B - Intent Met cooling.                                                                                                           diesel cooling.
Increased probability of recovery from failure Develop procedures to repair or       of breakers that transfer 4.16 kV non-                                       Spares exist and procedures 21                                                                                           Yes     B - Intent Met replace failed 4 KV breakers.         emergency buses from unit station service                                    exist.
transformers.
In training, emphasize steps in Reduced human error probability during off-22    recovery of off-site power after an                                                    Yes     B - Intent Met      Recovery stressed in training.
site power recovery.
SBO.
Develop a severe weather              Improved off-site power recovery following                                   Severe weather condition 23                                                                                           Yes     B - Intent Met conditions procedure.                 external weather-related events.                                             procedure in place.
Callaway has implemented a containment sump modification that now uses state-of-the-art strainers to 30    Improve ECCS suction strainers.       Enhanced reliability of ECCS suction.            Yes     B - Intent Met      address the industrys concerns on blockage from debris. This modification occurred over two outages in 2007 and 2008.
Add the ability to manually align                                                                                  Current alignment capabilities 31    emergency core cooling system         Enhanced reliability of ECCS suction.            Yes     B - Intent Met      are half and half recirculation.                                                                                                     (manual/automatic).
Add the ability to automatically align emergency core cooling                                                                                       Current alignment capabilities 32    system to recirculation mode upon     Enhanced reliability of ECCS suction.            Yes     B - Intent Met      are half and half refueling water storage tank                                                                                       (manual/automatic).
depletion.
Provide hardware and procedure to     Extended reactor water storage tank capacity refill the reactor water storage tank in the event of a steam generator tube                                       Addressed in SAMGs and the 33                                                                                           Yes     B - Intent Met once it reaches a specified low       rupture (or other LOCAs challenging RWST                                     EC Supplemental Guideline.
level.                                capacity).
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                          Page 41 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                          Discussion                            Screening Criterion      Phase I Disposition Out Ph 1?
Number Current alignment capabilities are half and half Emphasize timely recirculation     Reduced human error probability associated 36                                                                                        Yes     B - Intent Met      (manual/automatic). Swap to alignment in operator training. with recirculation failure.
recirculation is stressed in operator training.
For a plant like the Westinghouse AP600, Upgrade the chemical and volume    where the chemical and volume control CVCS system is capable of 37    control system to mitigate small   system cannot mitigate a small LOCA, an          Yes     B - Intent Met mitigating small LOCA.
LOCAs.                             upgrade would decrease the frequency of core damage.
Remote Operation of Provide capability for remote,     Improved chance of successful operation Atmospheric Steam Dumps manual operation of secondary side during station blackout events in which high 40                                                                                        Yes     B - Intent Met      (ASDs) is possible.
pilot-operated relief valves in a  area temperatures may be encountered (no Equipment Operators trained station blackout.                  ventilation to main stream areas).
and Operator Aid posted.
Make procedure changes for         Allows low pressure emergency core cooling Multiple depressurization 42    reactor coolant system             system injection in the event of small LOCA      Yes     B - Intent Met methods are in place.
depressurization.                  and high-pressure safety injection failure.
Current ECCS pump motors are air-cooled. Additionally Replace ECCS pump motors with      Elimination of ECCS dependency on 44                                                                                        Yes     B - Intent Met      the plant OTN procedures air-cooled motors.                 component cooling system.
allow for alternate trains to supply cooling.
Enhance procedural guidance for Reduced frequency of loss of component                                       Can use service water as 45    use of cross-tied component                                                         Yes     B - Intent Met cooling water and service water.                                             backup to ESW.
cooling or service water pumps.
Reduced frequency of loss of component Cap downstream piping of normally cooling water initiating events, some of which 48    closed component cooling water                                                      Yes     B - Intent Met      Vents & drains capped.
can be attributed to catastrophic failure of drain and vent valves.
one of the many single isolation valves.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                             Page 42 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA          Potential Improvement                              Discussion                            Screening Criterion      Phase I Disposition Out Ph 1?
Number Enhance loss of component cooling CCW is cooled by ESW.
water (or loss of service water)      Reduced potential for reactor coolant pump 49                                                                                           Yes     B - Intent Met      Currently authorized to run 10 procedures to facilitate stopping the seal damage due to pump bearing failure.
minutes.
reactor coolant pumps.
Enhance loss of component cooling water procedure to underscore the                                                                                  Procedures include direction Reduced probability of reactor coolant pump 50    desirability of cooling down the                                                       Yes     B - Intent Met      to cool down to minimize seal failure.
reactor coolant system prior to seal                                                                               impact of RCP seal LOCA.
LOCA.
Additional training on loss of        Improved success of operator actions after a                                 Training is conducted for Loss 51                                                                                           Yes     B - Intent Met component cooling water.              loss of component cooling water.                                             of CCW.
On loss of essential raw cooling                                                                                   Most non-safety loads have Increased time before loss of component water, proceduralize shedding                                                                                      been removed from the cooling water (and reactor coolant pump seal 53    component cooling water loads to                                                       Yes     B - Intent Met      system. Non-safety loop is failure) during loss of essential raw cooling extend the component cooling                                                                                       automatically isolated on water sequences.
water heat-up time.                                                                                                safety injection signal.
Reduced frequency of loss of reactor coolant pump seal cooling if spurious high pressure Prevent makeup pump flow                                                                                           Current configuration does not 60                                          injection relief valve opening creates a flow    Yes     B - Intent Met diversion through the relief valves.                                                                               have a relief valve.
diversion large enough to prevent reactor coolant pump seal injection.
Change procedures to isolate reactor coolant pump seal return flow on loss of component cooling Reduced frequency of core damage due to 61                                                                                           Yes     B - Intent Met      Procedure exist water, and provide (or enhance)       loss of seal cooling.
guidance on loss of injection during seal LOCA.
Implement procedures to stagger Extended high pressure injection prior to                                    Procedure currently in place 62    high pressure safety injection pump                                                    Yes     B - Intent Met overheating following a loss of service water.                               to stagger use of HPSI.
use after a loss of service water.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                               Page 43 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                             Discussion                              Screening Criterion      Phase I Disposition Out Ph 1?
Number Create ability for emergency connection of existing or new water 66                                          Increased availability of feedwater.               Yes     B - Intent Met      Procedures exist.
sources to feedwater and condensate systems.
Procedures do exist for make-Install an independent diesel for the up to CST from fire water and 67    condensate storage tank makeup        Extended inventory in CST during an SBO.           Yes     B - Intent Met for supplying fire water directly pumps.
to the TDAFW pump.
Add a motor-driven feedwater                                                                                         Non-Safety Auxiliary 68                                          Increased availability of feedwater.               Yes     B - Intent Met pump.                                                                                                                Feedwater Pump installed.
Install accumulators for turbine-     Eliminates the need for local manual action to Currently have nitrogen 70    driven auxiliary feedwater pump       align nitrogen bottles for control air following   Yes     B - Intent Met accumulators.
flow control valves.                  a loss of off-site power.
Turbine-driven auxiliary Modify the turbine-driven auxiliary   Improved success probability during a station 72                                                                                             Yes     B - Intent Met      feedwater pump is self-feedwater pump to be self-cooled. blackout.
cooled.
Extended auxiliary feedwater availability Proceduralize local manual            during a station blackout. Also provides a 73    operation of auxiliary feedwater      success path should auxiliary feedwater            Yes     B - Intent Met      Procedures exist.
system when control power is lost. control power be lost in non-station blackout sequences.
Provide hookup for portable generators to power the turbine-                                                                                     Procedures exist, hardware 74                                          Extended auxiliary feedwater availability.         Yes     B - Intent Met driven auxiliary feedwater pump                                                                                      on site.
after station batteries are depleted.
Equipment staged at CST for Use fire water system as a backup     Increased availability of steam generator                                      makeup.
75                                                                                             Yes     B - Intent Met for steam generator inventory.        water supply.                                                                  See operator aids.
Procedural guidance exists.
Change failure position of Allows greater inventory for the auxiliary condenser makeup valve if the 76                                          feedwater pumps by preventing condensate           Yes     B - Intent Met      Valve currently fails closed.
condenser makeup valve fails open storage tank flow diversion to the condenser.
on loss of air or power.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                              Page 44 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                           Discussion                               Screening Criterion       Phase I Disposition Out Ph 1?
Number Modify the startup feedwater pump Non-Safety Auxiliary so that it can be used as a backup Feedwater Pump gets power 78    to the emergency feedwater           Increased reliability of decay heat removal.       Yes     B - Intent Met from Alternate Emergency system, including during a station Power System.
blackout scenario.
Add a diesel building high                                                                                          Computer points for Improved diagnosis of a loss of diesel 81    temperature alarm or redundant                                                          Yes     B - Intent Met      monitoring diesel room building HVAC.
louver and thermostat.                                                                                              temperatures.
Procedures include Stage backup fans in switchgear      Increased availability of ventilation in the                                   instructions for opening doors 82                                                                                            Yes     B - Intent Met rooms.                               event of a loss of switchgear ventilation.                                     to provide alternate cooling capability.
Plant Process Computer has Add a switchgear room high           Improved diagnosis of a loss of switchgear 83                                                                                            Yes     B - Intent Met      alarming computer points for temperature alarm.                   HVAC.
switchgear room temperature.
Create ability to switch emergency feedwater room fan power supply                                                                                     Procedure currently in place 84                                         Continued fan operation in a station blackout. Yes     B - Intent Met to station batteries in a station                                                                                   to switch fan power supply.
blackout.
Currently have 3 air compressors (service air).
A/B compressors are powered off the emergency buses Modify procedure to provide ability Increased availability of instrument air after a                               (cooled from essential service 86    to align diesel power to more air                                                       Yes     B - Intent Met LOOP.                                                                          lines). Compressors are compressors.
initially load shed, but procedure direct operators to override and place compressor in service.
Current configuration includes Install nitrogen bottles as backup 88                                         Extended SRV operation time.                       Yes     B - Intent Met      nitrogen bottles as backup gas supply for safety relief valves.
gas supply.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                           Page 45 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                          Discussion                             Screening Criterion      Phase I Disposition Out Ph 1?
Number MSIV actuators changed to process fluid actuated.
Improve SRV and MSIV pneumatic 89                                       Improved availability of SRVs and MSIVs.          Yes     B - Intent Met      Modification installed to components.
relocate Atmospheric Steam Dump valve controllers.
Enhanced debris cool ability, reduced core Create a reactor cavity flooding 90                                       concrete interaction, and increased fission       Yes     B - Intent Met      Procedures exist system.
product scrubbing.
Use the fire water system as a 92    backup source for the containment  Improved containment spray capability.            Yes     B - Intent Met      Procedures exist spray system.
Increased potential to cool a molten core Provide a reactor vessel exterior 101                                       before it causes vessel failure, by               Yes     B - Intent Met      Procedures exist.
cooling system.
submerging the lower head in water.
Operators are trained on the Institute simulator training for   Improved arrest of core melt progress and 103                                                                                         Yes     B - Intent Met      SAMG that the operators must severe accident scenarios.         prevention of containment failure.
implement.
Increased likelihood that LOCAs outside containment are identified as such. A plant Revise EOPs to improve ISLOCA      had a scenario in which an RHR ISLOCA                                         Current EOPs address 117                                                                                         Yes     B - Intent Met identification.                    could direct initial leakage back to the                                      ISLOCA identification.
pressurizer relief tank, giving indication that the LOCA was inside containment.
Current procedure training Improve operator training on 118                                       Decreased ISLOCA consequences.                    Yes     B - Intent Met      addresses ISLOCA ISLOCA coping.
identification.
Replaced during the fall of Replace steam generators with a    Reduced frequency of steam generator tube                                     2005 (newer design) which 120                                                                                         Yes     B - Intent Met new design.                        ruptures.                                                                     consist of 72,000 sq. ft. per generator.
Proceduralize use of pressurizer   Backup method to using pressurizer sprays 123    vent valves during steam generator to reduce primary system pressure following       Yes     B - Intent Met      Procedure currently in place.
tube rupture sequences.            a steam generator tube rupture.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                             Page 46 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                          Discussion                               Screening Criterion      Phase I Disposition Out Ph 1?
Number Provide improved instrumentation Modification installed to to detect steam generator tube      Improved mitigation of steam generator tube 124                                                                                           Yes     B - Intent Met      improve operation of N16 ruptures, such as Nitrogen-16       ruptures.
detectors.
monitors).
Revise emergency operating Reduced consequences of a steam 127    procedures to direct isolation of a                                                    Yes     B - Intent Met      EOP currently in place.
generator tube rupture.
faulted steam generator.
Direct steam generator flooding                                                                                    Procedures direct that steam Improved scrubbing of steam generator tube 128    after a steam generator tube                                                           Yes     B - Intent Met      generator level be maintained rupture releases.
rupture, prior to core damage.                                                                                     above the tubes.
Provide an additional control Improved redundancy and reduced ATWS 132    system for rod insertion (e.g.,                                                        Yes     B - Intent Met      Currently have AMSAC.
frequency.
AMSAC).
Decreased time required to insert control Provide capability to remove power rods if the reactor trip breakers fail (during a 137    from the bus powering the control                                                      Yes     B - Intent Met      Response procedure in place.
loss of feedwater ATWS which has rapid rods.
pressure excursion).
Items are identified and are being implemented as part of the 805 process.
Install additional transfer and     Reduced number of spurious actuations 144                                                                                           Yes     B - Intent Met      Examples include fuse and isolation switches.                 during a fire.
alternate feed line modifications to prevent the loss of the 4160 V buses.
Most recent inspections and 145    Enhance fire brigade awareness. Decreased consequences of a fire.                  Yes     B - Intent Met      evaluations did not identify any weaknesses in this area.
Procedure in place. NFPA-Enhance control of combustibles                                                                                    805 project will evaluate the 146                                        Decreased fire frequency and consequences.         Yes     B - Intent Met and ignition sources.                                                                                              needs for any additional controls.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                            Page 47 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                             Discussion                           Screening Criterion      Phase I Disposition Out Ph 1?
Number Existing procedures meet Enhance procedures to mitigate         Reduced consequences of a large break 148                                                                                          Yes     B - Intent Met      current guidelines issued by large break LOCA.                      LOCA.
the Owner's Group.
Install computer aided instrumentation system to assist       Improved prevention of core melt sequences 149                                                                                          Yes     B - Intent Met      Currently have SPDS in place.
the operator in assessing post-        by making operator actions more reliable.
accident plant status.
Improved prevention of core melt sequences                                 Current procedures are in line 150    Improve maintenance procedures.        by increasing reliability of important         Yes     B - Intent Met      with industry guidelines and equipment.                                                                 practices.
Increase training and operating        Improved likelihood of success of operator                                 Current training program 151    experience feedback to improve         actions taken in response to abnormal          Yes     B - Intent Met      meets industry standards and operator response.                     conditions.                                                                practices.
Mount or anchor the MCCs to the        Reduces failure probability of MCCs during                                 Identified in the IPEEE and 154                                                                                          Yes     B - Intent Met respective building walls.             an earthquake                                                              successfully implemented.
Install shear pins (or strength bolts) Takes up the shear load on the pump and/or                                 Identified in the IPEEE and 155                                                                                          Yes     B - Intent Met in the AFW pumps.                      driver during an earthquake.                                               successfully implemented.
Mount all fire extinguishers within Reduces the potential for the fire their UL Standard required drop extinguishers to fall during an earthquake                                 Identified in the IPEEE and 156    height and remove hand-held fire                                                      Yes     B - Intent Met and potentially fracturing upon impact with                                successfully implemented.
extinguishers from Containment the floor or another object.
during normal operation.
Ensures direct access to areas such as Load Shedding and Emergency Load Sequencing Identify and remove unsecured (LSELS) and Engineered Safety Feature equipment near areas that contain                                                                                 Identified in the IPEEE and 157                                           Actuation                                      Yes     B - Intent Met relays that actuate, so area is kept                                                                              successfully implemented.
System (ESFAS) cabinets. Unsecured clear.
equipment (e.g., carts, filing cabinets, and test equipment) in these areas could result Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                           Page 48 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                            Discussion                           Screening Criterion       Phase I Disposition Out Ph 1?
Number Properly position chain hoists that Improper positioning of hoists reduces the facilitate maintenance on pumps availability due to moving during an within pump rooms and institute a                                                                                Identified in the IPEEE and 158                                         earthquake and having chainfalls impacting      Yes     B - Intent Met training program to ensure that the                                                                              successfully implemented.
pump oil bubblers or other soft targets hoists are properly positioned when resulting in failure of the pumps.
not in use.
Secure floor grating to prevent Prevent sensing lines that pass through the                                 Identified in the IPEEE and 159    damage to sensing lines due to                                                       Yes     B - Intent Met grating from being damaged.                                                 successfully implemented.
differential building motion.
Installation of high temperature                                                                                 High temperature O-Rings 166                                         Lower potential for RCP seal leakage.           Yes     B - Intent Met qualified RCP seal O-rings.                                                                                      installed.
Addition of procedural guidance to 167    re-establish normal service water    Provide back-up pumps for UHS cooling.          Yes     B - Intent Met      Procedures in place.
should essential service water fail.
Addition of procedural guidance for running charging and safety          Allow use of pumps following loss of 168                                                                                         Yes     B - Intent Met      Procedures in place.
injection pumps without component component cooling water.
cooling water Addition of procedural guidance to Verifying that support system for RHR pumps verify RHR pump room cooling at 169                                         is in service to allow continued operation of   Yes     B - Intent Met      Procedures in place.
switchover to ECCS recirculation RHR pumps.
phase.
AEPS diesel generators Modifications to add controls in the                                                                             automatically start upon loss main control room to allow remote                                                                                of offsite power to the local Faster ability to provide power to the plant operation of nearby diesel                                                                                       electrical co-op distribution 170                                         electrical busses from the offsite diesel       Yes     B - Intent Met generator farm and                                                                                               system. The controls for the generator farm.
alignment/connection to the plant                                                                                breakers to connect to the vital electrical busses.                                                                                         Callaway distribution system are in the main control room.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                          Page 49 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA          Potential Improvement                            Discussion                           Screening Criterion       Phase I Disposition Out Ph 1?
Number Addition of procedural guidance and the required hardware to Provide a backup to turbine driven auxiliary                               Procedure and hardware 172    enable the operators to feed one or                                                 Yes     B - Intent Met feedwater.                                                                 changes complete more steam generators with a diesel driven firewater pump.
The original evaluation of this proposed modification concluded that the cost for this modification was prohibitively high. However, this was subsequently Addition of a black start combustion A redundant source of AC Power that could 173                                                                                        Yes     B - Intent Met      changed and the offsite turbine generator.                   be used in station blackout events.
Alternate Emergency Power System (AEPS) system was installed. The AEPS system consists of diesel generators and a connection to the offsite electrical Co-op.
The original evaluation of this proposed modification concluded that the cost for this modification was Ability to power a 125VDC battery charger prohibitively high. However, and a charging pump. Powering the battery later implementation of the Addition of a black-start engine-    charger would permit operation of the TDAFP AEPS system provides the 174    generator to provide AC Power        without recovering AC power. Powering a        Yes     B - Intent Met backup power source during a station blackout            charging pump could provide RCP seal represented by this item. Also injection and preclude a RCP seal LOCA the EC Coordinator during a station blackout.
Supplemental Guidelines provide procedures and equipment for hookup of a portable generator.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                         Page 50 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                         Discussion                            Screening Criterion      Phase I Disposition Out Ph 1?
Number The positive displacement charging pump has been Replacement of the positive         Provide another source for RCP seal cooling,                               replaced by a centrifugal 175    displacement charging pump with a RCS makeup, and pumped flow for feed and         Yes     B - Intent Met      pump that does not require third centrifugal charging pump. bleed.                                                                     component cooling water. It is powered from a non-safety 4160 VAC power supply.
Allow faster and more reliable bypass of the Provide control modifications to                                                                               Feedwater Isolation bypass main feedwater isolation signal in order to 176    bypass feedwater isolation in order                                                Yes     B - Intent Met      switches installed and EOP in restore main feedwater to the steam to restore main feedwater.                                                                                     place with directions for use.
generators should auxiliary feedwater fail.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                      Page 51 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA          Potential Improvement                      Discussion                             Screening Criterion       Phase I Disposition Out Ph 1?
Number The flooding task force identified 3 generic recommendations; 1) evaluate the impact of the normal charging pump (NCP), 2) evaluate the impact of increased inspections or changes in pipe class on pipe failure probability, and 3) re-analyze pipe break flowrates for actual flow, rather than assuming pump runout The IPE identified a need to form a task force                               flowrates. All three Procedural and hardware        to identify and evaluate potential procedural                                recommendations have been modifications to reduce core   and hardware modifications aimed at                                          implemented. The flooding 177                                                                                    Yes     B - Intent Met damage risk due to internal    reducing the risk due to internal flooding.                                  analysis credited the NCP and flooding.                                                                                                   reduced one flood zone below the screening value. A leakage detection program was implemented which uses security personnel and operators to visually inspect specific piping in the major flood zones. The implementation of the leakage detection program reduced flooding risk sufficiently to not require the installation of some watertight doors and piping encapsulation.
Individual seismic issues Increase seismic ruggedness of Increased availability of necessary plant                                    identified in the IPEEE are 140                                                                                    Yes     C - Combined plant components.              equipment during and after seismic events.                                   included as SAMA items 154, 155, 156, 157, 158, and 159.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                            Page 52 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                         Discussion                               Screening Criterion      Phase I Disposition Out Ph 1?
Number Individual seismic issues Provide additional restraints for   Increased availability of fire protection given                               identified in the IPEEE are 141                                                                                          Yes     C - Combined CO2 tanks.                          a seismic event.                                                              included as SAMA items 154, 155, 156, 157, 158, and 159.
Original battery capacity is 4 Provide additional DC battery       Extended DC power availability during an                                      hrs. No additional battery 1                                                                                           No capacity.                           SBO.                                                                          capacity has been added.
Evaluate in Phase II.
Plant currently uses batteries Replace lead-acid batteries with    Extended DC power availability during an 2                                                                                           No                         rather than fuel cells.
fuel cells.                         SBO.
Evaluate in Phase II.
No existing capability for DC 5    Provide DC bus cross-ties.          Improved availability of DC power system.          No                         bus cross-ties. Evaluate in Phase II.
Improve 4.16-kV bus cross-tie 11                                        Increased availability of on-site AC power.        No                         Evaluate during Phase II ability.
No gas turbine currently installed. No tornado Install tornado protection on gas                                                                                 protection for Alternate 15                                        Increased availability of on-site AC power.        No turbine generator.                                                                                                Emergency Power System diesel generators. Evaluate in Phase II.
Improved off-site power reliability during 24    Bury off-site power lines.                                                             No                         Evaluate during Phase II severe weather.
Install an independent active or 25    passive high pressure injection     Improved prevention of core melt sequences.        No                         Evaluate during Phase II system.
Provide an additional high pressure Reduced frequency of core melt from small 26    injection pump with independent                                                        No                         Evaluate during Phase II LOCA and SBO sequences.
diesel.
Add a diverse low pressure 28                                        Improved injection capability.                     No                         Evaluate during Phase II injection system.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                            Page 53 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                          Discussion                              Screening Criterion       Phase I Disposition Out Ph 1?
Number Currently being evaluated by plant improvement program.
Would use unborated water and portable pump (fire truck).
Provide capability for alternate                                                                                  Calculation of specific benefit 29    injection via diesel-driven fire    Improved injection capability.                     No                         of this SAMA was not pump.                                                                                                             performed since it is judged to be potentially low cost.
Evaluation will consider impacts of injection of non-borated water.
Reduced common cause failure of the safety injection system. This SAMA was originally Replace two of the four electric intended for the Westinghouse-CE System 39    safety injection pumps with diesel-                                                    No                         Evaluate during Phase II 80+, which has four trains of safety injection.
powered pumps.
However, the intent of this SAMA is to provide diversity within the high- and l Allows low pressure emergency core cooling Create a reactor coolant 41                                        system injection in the event of small LOCA        No                         Evaluate during Phase II depressurization system.
and high-pressure safety injection failure.
Add redundant DC control power 43                                        Increased availability of SW.                      No                         Evaluate during Phase II for SW pumps.
46    Add a service water pump.           Increased availability of cooling water.           No                         Evaluate during Phase II Increased time before charging pump failure Increase charging pump lube oil 54                                        due to lube oil overheating in loss of cooling     No                         Evaluate during Phase II capacity.
water sequences.
Install an independent reactor      Reduced frequency of core damage from 55    coolant pump seal injection system, loss of component cooling water, service           No                         Evaluate during Phase II with dedicated diesel.              water, or station blackout.
Install an independent reactor      Reduced frequency of core damage from 56    coolant pump seal injection system, loss of component cooling water or service         No                         Evaluate during Phase II without dedicated diesel.           water, but not a station blackout.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                           Page 54 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway Screened SAMA           Potential Improvement                            Discussion                           Screening Criterion      Phase I Disposition Out Ph 1?
Number Install improved reactor coolant      Reduced likelihood of reactor coolant pump 58                                                                                          No                         Evaluate during Phase II pump seals.                           seal LOCA.
Reduced likelihood of loss of component Install an additional component 59                                          cooling water leading to a reactor coolant      No                         Evaluate during Phase II cooling water pump.
pump seal LOCA.
Implement procedure and hardware modifications to allow manual alignment of the fire water system Improved ability to cool residual heat removal 64                                                                                          No                         Evaluate during Phase II to the component cooling water        heat exchangers.
system, or install a component cooling water header cross-tie.
Reduced chance of loss of main feed water 65    Install a digital feed water upgrade.                                                 No                         Evaluate during Phase II following a plant trip.
Install a new condensate storage Increased availability of the auxiliary 71    tank (auxiliary feedwater storage                                                     No                         Evaluate during Phase II feedwater system.
tank).
Provide a passive, secondary-side Reduced potential for core damage due to 77    heat-rejection loop consisting of a                                                   No                         Evaluate during Phase II loss-of-feedwater events.
condenser and heat sink.
Replace existing pilot-operated relief valves with larger ones, such  Increased probability of successful feed and 79                                                                                          No                         Evaluate during Phase II that only one is required for         bleed.
successful feed and bleed.
Provide a redundant train or means Increased availability of components 80                                                                                          No                         Evaluate during Phase II of ventilation.                       dependent on room cooling.
Replace service and instrument air compressors with more reliable                                                                                   Air compressors currently Elimination of instrument air system 87    compressors which have self-                                                          No                         cooled by ESW. Evaluate dependence on service water cooling.
contained air cooling by shaft                                                                                   during Phase II driven fans.
Install a passive containment spray 91                                          Improved containment spray capability.          No                         Evaluate during Phase II system.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                           Page 55 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway SAMA                                                                                       Screened Number          Potential Improvement                              Discussion               Out Ph 1? Screening Criterion     Phase I Disposition 93    Install an unfiltered, hardened        Increased decay heat removal capability for    No                         Evaluate during Phase II containment vent.                      non-ATWS events, without scrubbing released fission products.
94    Install a filtered containment vent to Increased decay heat removal capability for    No                         Evaluate during Phase II remove decay heat. Option 1:           non-ATWS events, with scrubbing of Gravel Bed Filter; Option 2:           released fission products.
Multiple Venturi Scrubber 96    Provide post-accident containment Reduced likelihood of hydrogen and carbon           No                         Evaluate during Phase II inerting capability.                   monoxide gas combustion.
97    Create a large concrete crucible       Increased cooling and containment of molten    No                         Evaluate during Phase II with heat removal potential to         core debris. Molten core debris escaping contain molten core debris.            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.
98    Create a core melt source              Increased cooling and containment of molten    No                         Evaluate during Phase II reduction system.                      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.
99    Strengthen primary/secondary           Reduced probability of containment over-       No                         Evaluate during Phase II containment (e.g., add ribbing to      pressurization.
containment shell).
100    Increase depth of the concrete         Reduced probability of base mat melt-          No                         Evaluate during Phase II base mat or use an alternate           through.
concrete material to ensure melt-through does not occur.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                           Page 56 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway SAMA                                                                                       Screened Number          Potential Improvement                            Discussion                 Out Ph 1? Screening Criterion     Phase I Disposition 102    Construct a building to be             Reduced probability of containment over-       No                         Evaluate during Phase II connected to primary/secondary         pressurization.
containment and maintained at a vacuum.
104    Improve leak detection procedures. Increased piping surveillance to identify leaks    No                         Evaluate during Phase II prior to complete failure. Improved leak detection would reduce LOCA frequency.
107    Install a redundant containment        Increased containment heat removal ability. No                         Evaluate during Phase II spray system.
108    Install an independent power           Reduced hydrogen detonation potential.         No                         Evaluate during Phase II 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.
109    Install a passive hydrogen control     Reduced hydrogen detonation potential.         No                         Evaluate during Phase II system.
110    Erect a barrier that would provide     Reduced probability of containment failure. No                         Evaluate during Phase II enhanced protection of the containment walls (shell) from ejected core debris following a core melt scenario at high pressure.
111    Install additional pressure or leak    Reduced ISLOCA frequency.                      No                         Evaluate during Phase II monitoring instruments for detection of ISLOCAs.
112    Add redundant and diverse limit        Reduced frequency of containment isolation     No                         Evaluate during Phase II switches to each containment           failure and ISLOCAs.
isolation valve.
113    Increase leak testing of valves in     Reduced ISLOCA frequency.                      No                         Evaluate during Phase II ISLOCA paths.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                        Page 57 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway SAMA                                                                                    Screened Number          Potential Improvement                             Discussion             Out Ph 1? Screening Criterion      Phase I Disposition 114    Install self-actuating containment      Reduced frequency of isolation failure. No                         Evaluate during Phase II isolation valves.
115    Locate residual heat removal            Reduced frequency of ISLOCA outside        No                         Evaluate during Phase II (RHR) inside containment                containment.
116    Ensure ISLOCA releases are              Scrubbed ISLOCA releases.                  No                         Evaluate during Phase II scrubbed. One method is to plug drains in potential break areas so that break point will be covered with water.
119    Institute a maintenance practice to Reduced frequency of steam generator tube      No                         Current frequency of perform a 100% inspection of            ruptures.                                                             inspection of SG tubes is steam generator tubes during each                                                                             100% inspection every third refueling outage.                                                                                             outage.
Evaluate during Phase II 121    Increase the pressure capacity of       Eliminates release pathway to the          No                         Evaluate during Phase II the secondary side so that a steam environment following a steam generator generator tube rupture would not        tube rupture.
cause the relief valves to lift.
122    Install a redundant spray system to Enhanced depressurization capabilities         No                         Evaluate during Phase II depressurize the primary system         during steam generator tube rupture.
during a steam generator tube rupture 125    Route the discharge from the main Reduced consequences of a steam                  No                         Evaluate during Phase II steam safety valves through a           generator tube rupture.
structure where a water spray would condense the steam and remove most of the fission products.
126    Install a highly reliable (closed loop) Reduced consequences of a steam            No                         Evaluate during Phase II steam generator shell-side heat         generator tube rupture.
removal system that relies on natural circulation and stored water sources Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                           Page 58 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway SAMA                                                                                       Screened Number          Potential Improvement                          Discussion                   Out Ph 1? Screening Criterion     Phase I Disposition 129    Vent main steam safety valves in    Reduced consequences of a steam                   No                         Evaluate during Phase II containment.                        generator tube rupture.
130    Add an independent boron injection Improved availability of boron injection during    No                         Evaluate during Phase II system.                             ATWS.
131    Add a system of relief valves to    Improved equipment availability after an          No                         Evaluate during Phase II prevent equipment damage from       ATWS.
pressure spikes during an ATWS.
133    Install an ATWS sized filtered      Increased ability to remove reactor heat from     No                         Evaluate during Phase II containment vent to remove decay    ATWS events.
heat.
136    Install motor generator set trip    Reduced frequency of core damage due to           No                         Evaluate during Phase II breakers in control room.           an ATWS.
147    Install digital large break LOCA    Reduced probability of a large break LOCA         No                         Evaluate during Phase II protection system.                  (a leak before break).
153    Install secondary side guard pipes  Prevents secondary side depressurization          No                         Evaluate during Phase II up to the main steam isolation      should a steam line break occur upstream of valves.                             the main steam isolation valves. Also guards against or prevents consequential multiple steam generator tube ruptures following a main steam line break event.
160    Modifications to lessen impact of   Lower impact of flood that propagates             No                         Evaluate during Phase II internal flooding path through      through the dumbwaiter Control Building dumbwaiter.
161    Improvements to PORV                Decrease in risk due to PORV failing to open. No                         Evaluate during Phase II performance that will lower the probability of failure to open.
162    Install a large volume EDG fuel oil Allows transfer of EDF fuel oil to the EDG        No                         Evaluate during Phase II tank at an elevation greater than   day tanks on failure of the fuel oil transfer the EDG fuel oil day tanks.         pumps.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                             Page 59 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway SAMA                                                                                         Screened Number          Potential Improvement                            Discussion                   Out Ph 1? Screening Criterion       Phase I Disposition 163    Improve feedwater check valve         Lower risk due to failures in which feedwater     No                         Valves replaced with new reliability to reduce probability of  check valves fail to open and allow feeding of                               type, but are still significant failure to open.                      the steam generators.                                                        risk contributor. Evaluate in Phase II.
164    Provide the capability to power the   Provide backup to ESW in conditions with          No                         Evaluate during Phase II normal service water pumps from       power only available from AEPS.
AEPS.
171    Increase the size of the RWST or      Ensure a supply of makeup water is available      No                         Evaluate during Phase II otherwise improve the availability of from the RWST.
the RWST 178    Improvements to UHS cooling           Improve availability or mitigate loss of HVAC. No                         Evaluate during Phase II tower electrical room HVAC.
179    Modify procedures such that the       Prevents possible thermally induced steam         No                         Evaluate during Phase II water loop seals in the RCS cold      generator tube rupture following core legs are not cleared following core   damage.
damage.
180    Install lower amperage fuses for      Reduced fire risk.                                No                         Evaluate during Phase II 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.
181    Install redundant fuses and           Reduced fire risk.                                No                         Evaluate during Phase II isolation switches for MCR evacuation procedure OTO-ZZ-00001.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                                 Page 60 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway SAMA                                                                                             Screened Number          Potential Improvement                               Discussion                    Out Ph 1? Screening Criterion     Phase I Disposition 182    To protect against multiple spurious Reduced fire risk.                                     No                         Evaluate during Phase II 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.
183    Quick response sprinkler heads in Reduced fire risk.                                        No                         Evaluate during Phase II 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.
184    Improvements in the reliability of       More reliable main steam line isolation.           No                         Evaluate during Phase II the Steam Line Isolation automatic signal.
185    Automate initiation of CCW flow to       More reliable than manual initiation of flow to    No                         Evaluate during Phase II the RHR heat exchangers.                 RRHR HX.
186    Develop a procedure and obtain           Backup cooling water if ESW/SW is lost             No                         Evaluate during Phase II equipment to provide a temporary hookup of fire water as a replacement for ESW 187    Install modification to power the        Another source of backup power to the NCP          No                         Evaluate during Phase II normal charging pump from an             in cases of station blackout or loss of service existing spare breaker from the          water AEPS.
188    Install a permanent, dedicated           Another source of backup power to the NCP,         No                         Evaluate during Phase II generator for the NCP, and a             DC power (pump/valve control and SG level motor-driven AFW pump and                instrumentation), and power to an AFW pump battery charger to address SBO           in cases of station blackout or loss of service events in which the TD AFW pump          water is unavailable.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                                           Page 61 of 86 Table 6-1. Callaway Plant Phase I SAMA Analysis Callaway SAMA                                                                                       Screened Number         Potential Improvement                           Discussion                   Out Ph 1? Screening Criterion    Phase I Disposition 189    Perform analysis to determine if it is Reduction in risk due to internal flooding. No                          Evaluate during Phase II possible to modify current plant doors to withstand higher flood heights. Either perform modifications to install improved doors or revise flooding analysis to incorporate results that doors will withstand higher flooding heights without propagating the flood.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                          Page 62 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                                    % Red.
                                                                     % Red.         SAMA       SAMA Case SAMA       Potential Improvement                Discussion                  In OS                               Benefit  Cost   % Red  Cost Basis   Evaluation     Basis for Evaluation In CDF          Case      Description Number                                                                       Dose                                               IN OECR Provide additional DC battery Extended DC power                                   No Station Blackout                                        Not Cost-1                                                                12.17% 10.87% NOSBO                         $360K    >$1M   10.49% Expert Panel             Cost will exceed benefit.
capacity.                     availability during an SBO.                                Events                                              Beneficial Replace lead-acid batteries   Extended DC power                                   No Station Blackout                                        Not Cost-2                                                                12.17% 10.87% NOSBO                         $360K    >$1M   10.49% Expert Panel             Cost will exceed benefit.
with fuel cells.              availability during an SBO.                                Events                                              Beneficial Improved availability of DC                            TDAFW no DC                                             Not Cost-5    Provide DC bus cross-ties.                                   0.30% 0.00%    DC01                          $1K   >$199K   0.03% Expert Panel             Cost will exceed benefit.
power system.                                           Dependency                                             Beneficial Physical cross-tie exists, but there is no analysis or procedures to allow its use except in specific outage conditions. Cost is to Add 4KV cross-tie                                        Potentially Improve 4.16-kV bus cross-    Increased availability of on-                                                                                             develop procedures and 11                                                                 0.26% 0.58%    4kv2   capability for SBO    $13K   <$100K   0.58% Expert Panel    Cost-tie ability.                  site AC power.                                                                                                            analysis to allow use of the sequences                                             Beneficial cross-tie. Benefit calculated is under-estimated since it was evaluated for only SBO sequences.
Install tornado protection on Increased availability of on-                       No tornado related                                         Not Cost-15                                                                 2.65% 4.35%   LOSP1                         $91K   >$500K   3.38% Expert Panel             Cost will exceed benefit.
gas turbine generator.        site AC power.                                             LOSP                                                Beneficial Cost will exceed benefit.
Improved off-site power                                                                                                   Previous SAMA submittals Eliminate all Loss of                                      Not Cost-24    Bury off-site power lines. reliability during severe     40.66% 41.30% NOLOSP                        $1.2M    >$3M   35.28% Expert Panel             have estimated Offsite Power Events                                        Beneficial weather.                                                                                                                  approximately $1M per mile.
Install an independent active Improved prevention of                               No failures of the                                        Not Cost-25    or passive high pressure                                    16.46% 0.00%  LOCA12                        $616K   >$1.5M  22.61% Expert Panel             Cost will exceed benefit.
core melt sequences.                               charging or SI pumps                                        Beneficial injection system.
Provide an additional high    Reduced frequency of core No failures of the                                        Not Cost-26    pressure injection pump with  melt from small LOCA and      16.46% 0.00%  LOCA12                        $616K   >$1.5M  22.61% Expert Panel             Cost will exceed benefit.
charging or SI pumps                                        Beneficial independent diesel.           SBO sequences.
Add a diverse low pressure    Improved injection                                    No failure of low                                        Not Cost-28                                                                 3.19% 2.17%  LOCA03                         $65K    >$1M    1.01% Expert Panel             Cost will exceed benefit.
injection system.             capability.                                          pressure injection                                        Beneficial Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                         Page 63 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                                    % Red.
                                                                     % Red.          SAMA       SAMA Case SAMA        Potential Improvement                Discussion                 In OS                              Benefit  Cost   % Red  Cost Basis    Evaluation     Basis for Evaluation In CDF          Case       Description Number                                                                       Dose                                              IN OECR SAMA is judged to be low cost, but analysis is needed to determine impacts of injection of non-Provide capability for                                                                                                                      Potentially borated water to RCS.
Improved injection 29    alternate injection via diesel-                                                                                                                Cost-capability.                                                                                                             Expert Panel judged this driven fire pump.                                                                                                                            Beneficial SAMA to be potentially cost-beneficial without determining an actual benefit or cost.
Reduced common cause failure of the safety injection system. This SAMA was originally Replace two of the four         intended for the electric safety injection       Westinghouse-CE System                              No failures of the                                     Not Cost-39                                                                16.46% 0.00%   LOCA12                      $616K   >$1.5M  22.61% Expert Panel              Cost will exceed benefit.
pumps with diesel-powered       80+, which has four trains                        charging or SI pumps                                     Beneficial pumps.                          of safety injection.
However, the intent of this SAMA is to provide diversity within the high-and l Allows low pressure emergency core cooling Create a reactor coolant        system injection in the                               No failures of                                       Not Cost-41                                                                 0.78% 0.00%  DEPRESS                       $12K   >$500K   0.27% Expert Panel              Cost will exceed benefit.
depressurization system.        event of small LOCA and                             depressurization                                       Beneficial high-pressure safety injection failure.
Service Water Pumps Add redundant DC control        Increased availability of                                                                                  Not Cost-43                                                                 0.30% 0.00%    SW01  not dependent on DC    $1K   >$100K   0.06% Expert Panel              Cost will exceed benefit.
power for SW pumps.             SW.                                                                                                        Beneficial Power Increased availability of                          No failures of ESW                                      Not Cost-46    Add a service water pump.                                   17.60% 27.72%   SW02                       $636K    >$5M   23.26% Expert Panel              Cost will exceed benefit.
cooling water.                                            pumps                                            Beneficial Increased time before charging pump failure due                         Charging pumps not Increase charging pump lube                                                                                                                Not Cost-54                                    to lube oil overheating in   0.48% 0.00%   CHG01  dependent on cooling  $4K    >$100K   0.06% Expert Panel              Cost will exceed benefit.
oil capacity.                                                                                                                              Beneficial loss of cooling water                                     water.
sequences.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                           Page 64 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                                     % Red.
                                                                      % Red.         SAMA       SAMA Case SAMA       Potential Improvement                Discussion                  In OS                                Benefit  Cost    % Red Cost Basis    Evaluation     Basis for Evaluation In CDF          Case      Description Number                                                                       Dose                                                IN OECR Cost will exceed benefit.
Previous investigation into Reduced frequency of core Install an independent                                                                                                                                    installing such a system damage from loss of reactor coolant pump seal                                                  RCPLOC                                                            Not Cost-    concluded that operators 55                                   component cooling water,       5.54% 0.00%          No RCP Seal LOCAs      $94K    >$1M    0.21% Expert Panel injection system, with                                                        A                                                              Beneficial   did not have sufficient time service water, or station dedicated diesel.                                                                                                                                         to place the system in blackout.
service prior to seal damage.
Reduced frequency of core Install an independent damage from loss of reactor coolant pump seal                                                  RCPLOC                                                            Not Cost-56                                   component cooling water        5.54% 0.00%          No RCP Seal LOCAs      $94K   >$500K   0.21% Expert Panel              Cost will exceed benefit.
injection system, without                                                     A                                                              Beneficial or service water, but not a dedicated diesel.
station blackout.
Reduced likelihood of Install improved reactor                                                   RCPLOC                                                            Not Cost-58                                   reactor coolant pump seal      5.54% 0.00%          No RCP Seal LOCAs      $94K    >$3M    0.21% Expert Panel              Cost will exceed benefit.
coolant pump seals.                                                           A                                                              Beneficial LOCA.
Reduced likelihood of loss Install an additional of component cooling water                         No failures of the CCW                                     Not Cost-59    component cooling water                                       3.61% 0.00%   CCW01                         $59K    >$1M    0.07% Expert Panel              Cost will exceed benefit.
leading to a reactor coolant                                Pumps                                             Beneficial pump.
pump seal LOCA.
Implement procedure and The cost estimate is for hardware modifications to development of a allow manual alignment of Improved ability to cool                                                                                       Potentially procedure and use of the fire water system to the                                                        Evaluate fire water 64                                   residual heat removal heat     5.39% 0.76%  FWCCW2                        $104K   <$150K  0.77%% Expert Panel     Cost     temporary connections.
component cooling water                                                             hookup to RHR HX exchangers.                                                                                                     Beneficial Cost of permanent system, or install a modification would be component cooling water significantly higher.
header cross-tie.
Reduced chance of loss of                                                                         Callaway Install a digital feed water                                                       No loss of Feedwater                                        Not Cost-65                                   main feed water following a    1.57% 0.00%    FW01                         $29K    $19M    0.49% Modification              Cost will exceed benefit.
upgrade.                                                                                   Events                                              Beneficial plant trip.                                                                                         Costs Install a new condensate Increased availability of the                                                                                   Not Cost-71    storage tank (auxiliary                                       1.14% 0.00%   CST01 CST does not deplete    $18K   >$2.5M   0.24% Expert Panel              Cost will exceed benefit.
auxiliary feedwater system.                                                                                     Beneficial feedwater storage tank).
Provide a passive, Reduced potential for core secondary-side heat-                                                               No loss of Feedwater                                        Not Cost-77                                   damage due to loss-of-         1.57% 0.00%    FW01                         $29K    $>1M    0.49% Expert Panel              Cost will exceed benefit.
rejection loop consisting of a                                                             Events                                              Beneficial feedwater events.
condenser and heat sink.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                           Page 65 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                                   % Red.
                                                                    % Red.         SAMA        SAMA Case SAMA       Potential Improvement                Discussion                 In OS                                 Benefit  Cost   % Red  Cost Basis   Evaluation     Basis for Evaluation In CDF          Case       Description Number                                                                      Dose                                                 IN OECR Replace existing pilot-operated relief valves with                                                         Only one PORV Increased probability of                                                                                       Not Cost-79    larger ones, such that only                                 3.43% 2.17%    FB01   required for Feed &     $79K   >$500K   1.68% Expert Panel             Cost will exceed benefit.
successful feed and bleed.                                                                                     Beneficial one is required for successful                                                           Bleed feed and bleed.
Procedures to open doors or provide temporary ventilation may be cost Increased availability of                                                                                     Potentially beneficial for the EDGs, Provide a redundant train or                                                      No dependencies on 80                                   components dependent on      6.08% 4.35%   HVAC                           $156K   <$100K   3.87% Expert Panel    Cost     MDAFW pumps, and means of ventilation.                                                                    HVAC room cooling.                                                                                                  Beneficial charging pumps.
Procedures for opening doors to the DC switchgear rooms exist.
Replace service and instrument air compressors Elimination of instrument with more reliable                                                                    Eliminate all                                           Not Cost-87                                   air system dependence on     0.36% 0.00%  INSTAIR                           $2K   >$500K   0.06% Expert Panel             Cost will exceed benefit.
compressors which have                                                           instrument air failures                                      Beneficial service water cooling.
self-contained air cooling by shaft driven fans.
No failures due to Install a passive containment Improved containment                                                                                            Not Cost-91                                                               19.52% 36.96% CONT01       containment        $793K   >$10M   31.32% Expert Panel             Cost will exceed benefit.
spray system.                  spray capability.                                                                                              Beneficial overpressure Increased decay heat removal capability for non-                         No failures due to Install an unfiltered,                                                                                                                        Not Cost-93                                   ATWS events, without        19.52% 36.96% CONT01       containment        $793K    >$2M   31.32% Expert Panel             Cost will exceed benefit.
hardened containment vent.                                                                                                                    Beneficial scrubbing released fission                             overpressure products.
Install a filtered containment Increased decay heat vent to remove decay heat. removal capability for non-                         No failures due to Not Cost-94    Option 1: Gravel Bed Filter;   ATWS events, with           19.52% 36.96% CONT01       containment        $793K    >$2M   31.32% Expert Panel             Cost will exceed benefit.
Beneficial Option 2: Multiple Venturi     scrubbing of released                                  overpressure Scrubber                       fission products.
Provide post-accident          Reduced likelihood of No hydrogen                                             Not Cost-96    containment inerting           hydrogen and carbon          0.48% 0.00%  H2BURN                           $10K   >$100K   0.44% Expert Panel             Cost will exceed benefit.
burns/explosions                                          Beneficial capability.                    monoxide gas combustion.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                    Page 66 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                                    % Red.
                                                                     % Red.         SAMA    SAMA Case                      % Red SAMA       Potential Improvement                 Discussion                 In OS                           Benefit  Cost        Cost Basis   Evaluation    Basis for Evaluation In CDF         Case    Description                      IN Number                                                                       Dose OECR Increased cooling and containment of molten core debris. Molten core debris Create a large concrete        escaping from the vessel is crucible with heat removal     contained within the                                                                                    Not Cost-97                                                                                MAB                             >$10M Note 1 Expert Panel             Cost will exceed benefit.
potential to contain molten    crucible and a water                                                                                    Beneficial core debris.                   cooling mechanism cools the molten core in the crucible, preventing melt-through of the base mat.
Increased cooling and containment of molten core debris. Refractory material would be placed underneath the reactor vessel such that a molten Create a core melt source      core falling on the material                                                                            Not Cost-98                                                                                MAB                             >$10M Note 1 Expert Panel             Cost will exceed benefit.
reduction system.              would melt and combine                                                                                  Beneficial with the material.
Subsequent spreading and heat removal from the vitrified compound would be facilitated, and concrete attack would not occur.
Strengthen Reduced probability of                            No failures due to primary/secondary                                                                                                                      Not Cost-99                                   containment over-            19.52% 36.96% CONT01   containment      $1.2M   >$10M 31.32% Expert Panel             Cost will exceed benefit.
containment (e.g., add                                                                                                                 Beneficial pressurization.                                     overpressure ribbing to containment shell).
Increase depth of the concrete base mat or use an Reduced probability of                                                                                  Not Cost-100    alternate concrete material to                                              MAB                             >$10M Note 1 Expert Panel             Cost will exceed benefit.
base mat melt-through.                                                                                  Beneficial ensure melt-through does not occur.
Construct a building to be connected to                   Reduced probability of                            No failures due to Not Cost-102    primary/secondary              containment over-            19.52% 36.96% CONT01   containment      $1.2M   >$10M 31.32% Expert Panel             Cost will exceed benefit.
Beneficial containment and maintained     pressurization.                                     overpressure at a vacuum.
Increased piping surveillance to identify Improve leak detection         leaks prior to complete                           No piping system                                      Not Cost-104                                                                39.34% 2.17%  LOCA05                    $689K   >$2M  1.03%  Expert Panel             Cost will exceed benefit.
procedures.                    failure. Improved leak                                 LOCAs                                            Beneficial detection would reduce LOCA frequency.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                  Page 67 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                              % Red.
                                                               % Red.         SAMA      SAMA Case                        % Red SAMA       Potential Improvement                Discussion            In OS                              Benefit  Cost         Cost Basis   Evaluation     Basis for Evaluation In CDF          Case     Description                        IN Number                                                                 Dose OECR No failures due to Install a redundant            Increased containment                                                                                 Not Cost-107                                                          19.52% 36.96% CONT01     containment       $1.2M    >$2M  31.32% Expert Panel             Cost will exceed benefit.
containment spray system.      heat removal ability.                                                                                 Beneficial overpressure Install an independent power supply to the hydrogen control system using either new batteries, a non-safety Reduced hydrogen                                No hydrogen                                           Not Cost-108    grade portable generator,                              0.48% 0.00%  H2BURN                        $10K   >$100K 0.44%  Expert Panel detonation potential.                         burns/explosions                                        Beneficial existing station batteries, or existing AC/DC independent power supplies, such as the security system diesel.
Install a passive hydrogen     Reduced hydrogen                                No hydrogen                                           Not Cost-109                                                           0.48% 0.00%  H2BURN                        $10K   >$100M 0.44%  Expert Panel             Cost will exceed benefit.
control system.                detonation potential.                         burns/explosions                                        Beneficial Erect a barrier that would provide enhanced protection of the containment walls       Reduced probability of                                                                                Not Cost-110                                                                          MAB                                >$10M  Note 1 Expert Panel             Cost will exceed benefit.
(shell) from ejected core      containment failure.                                                                                  Beneficial debris following a core melt scenario at high pressure.
Install additional pressure or Reduced ISLOCA                                                                                        Not Cost-111    leak monitoring instruments                            1.33% 8.70%  ISLOCA  No ISLOCA events     $123K   >$500K 7.08%  Expert Panel             Cost will exceed benefit.
frequency.                                                                                            Beneficial for detection of ISLOCAs.
Add redundant and diverse      Reduced frequency of No failures of                                        Not Cost-112    limit switches to each         containment isolation   0.30% 0.00%  CONT02                         $1K    >$1M         Expert Panel             Cost will exceed benefit.
containment isolation                                     Beneficial containment isolation valve. failure and ISLOCAs.
Increase leak testing of       Reduced ISLOCA                                                                                        Not Cost-113                                                           1.33% 8.70%  ISLOCA  No ISLOCA events     $123K    >$1M  7.08%  Expert Panel             Cost will exceed benefit.
valves in ISLOCA paths.        frequency.                                                                                            Beneficial Install self-actuating         Reduced frequency of                            No failures of                                        Not Cost-114                                                           0.30% 0.00%  CONT02                         $1K   >$500K 0.03%  Expert Panel             Cost will exceed benefit.
containment isolation valves. isolation failure.                           containment isolation                                     Beneficial Reduced frequency of Locate residual heat removal                                                                                                         Not Cost-115                                   ISLOCA outside          1.33% 8.70%  ISLOCA  No ISLOCA events     $123K    >$1M  7.08%  Expert Panel             Cost will exceed benefit.
(RHR) inside containment                                                                                                             Beneficial containment.
Cost would exceed benefit.
Ensure ISLOCA releases are                                                                                                                      Current plant design scrubbed. One method is to                                                                                                                      requires drains to be open.
Scrubbed ISLOCA                                                                                       Not Cost-116    plug drains in potential break                         1.33% 8.70%  ISLOCA  No ISLOCA events     $123K    >$1M  7.08%  Expert Panel             Analysis and license releases.                                                                                             Beneficial areas so that break point will                                                                                                                  changes required to be covered with water.                                                                                                                          implement are included in the cost estimate.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                   Page 68 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                                   % Red.
                                                                    % Red.         SAMA     SAMA Case                     % Red SAMA         Potential Improvement              Discussion                 In OS                           Benefit  Cost        Cost Basis   Evaluation     Basis for Evaluation In CDF         Case     Description                     IN Number                                                                      Dose OECR Institute a maintenance practice to perform a 100%     Reduced frequency of        20.47%                                                69.43%               Not Cost-119    inspection of steam            steam generator tube               63.28% NOSGTR  No SGTR Events    $1.4M   >$3M         Expert Panel             Cost will exceed benefit.
Beneficial generator tubes during each    ruptures.
refueling outage.
Increase the pressure capacity of the secondary      Eliminates release pathway side so that a steam           to the environment          20.47%                                          >$10M 69.43%               Not Cost-121                                                                      63.28% NOSGTR  No SGTR Events    $1.4M                Expert Panel             Cost will exceed benefit.
generator tube rupture would   following a steam                                                                                      Beneficial not cause the relief valves to generator tube rupture.
lift.
Install a redundant spray Enhanced depressurization 20.47%                                            >$10M 69.43%
system to depressurize the                                                                                                            Not Cost-122                                   capabilities during steam          63.28% NOSGTR  No SGTR Events    $1.4M                Expert Panel             Cost will exceed benefit.
primary system during a                                                                                                               Beneficial generator tube rupture.
steam generator tube rupture Route the discharge from the main steam safety valves Reduced consequences of     20.47%                                          >$10M 69.43%
through a structure where a                                                                                                           Not Cost-125                                   a steam generator tube             63.28% NOSGTR  No SGTR Events    $1.4M                Expert Panel             Cost will exceed benefit.
water spray would condense                                                                                                            Beneficial rupture.
the steam and remove most of the fission products.
Install a highly reliable (closed loop) steam Reduced consequences of     20.47%                                          >$10M 69.43%
generator shell-side heat                                                                                                             Not Cost-126                                   a steam generator tube             63.28% NOSGTR  No SGTR Events    $1.4M                Expert Panel             Cost will exceed benefit.
removal system that relies on                                                                                                         Beneficial rupture.
natural circulation and stored water sources Cost will exceed benefit.
Current containment design does not support this Reduced consequences of     20.47%                                          >$10M 69.43%
Vent main steam safety                                                                                                                Not Cost-  modification. Modifications 129                                   a steam generator tube             63.28% NOSGTR  No SGTR Events    $1.4M                Expert Panel valves in containment.                                                                                                                Beneficial to containment and rupture.
associated analysis are included in the cost estimate.
Improved availability of Add an independent boron                                                                                                              Not Cost-130                                   boron injection during       2.41% 2.17%  NOATWS Eliminate all ATWS  $63K   >$1M  1.85%  Expert Panel             Cost will exceed benefit.
injection system.                                                                                                                     Beneficial ATWS.
Add a system of relief valves to prevent equipment           Improved equipment                                                                                     Not Cost-131                                                                2.41% 2.17%  NOATWS Eliminate all ATWS  $63K   >$2M  1.85%  Expert Panel             Cost will exceed benefit.
damage from pressure           availability after an ATWS.                                                                            Beneficial spikes during an ATWS.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                          Page 69 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                                      % Red.
                                                                       % Red.          SAMA     SAMA Case                         % Red SAMA        Potential Improvement                Discussion                  In OS                                Benefit   Cost       Cost Basis    Evaluation      Basis for Evaluation In CDF          Case     Description                         IN Number                                                                        Dose OECR Install an ATWS sized filtered Increased ability to remove Not Cost-133    containment vent to remove reactor heat from ATWS              2.41% 2.17%  NOATWS  Eliminate all ATWS     $63K    >$1M  1.85% Expert Panel              Cost will exceed benefit Beneficial decay heat.                     events.
Install motor generator set     Reduced frequency of core                                                                                     Not Cost-136                                                                   2.41% 2.17%  NOATWS  Eliminate all ATWS     $63K   >$500K 1.85% Expert Panel              Cost will exceed benefit.
trip breakers in control room. damage due to an ATWS.                                                                                         Beneficial Reduced probability of a Install digital large break                                                          No piping system                                         Not Cost-147                                    large break LOCA (a leak      39.34% 2.17%   LOCA05                       $689K    >$5M  1.03% Expert Panel              Cost will exceed benefit.
LOCA protection system.                                                                   LOCAs                                               Beneficial before break).
Prevents secondary side depressurization should a steam line break occur upstream of the main Install secondary side guard    steam isolation valves.
No Steam Line                                           Not Cost-153    pipes up to the main steam      Also guards against or         2.53% 0.00%   NOSLB                         $51K    >$1M  0.87% Expert Panel              Cost will exceed benefit.
Breaks                                              Beneficial isolation valves.               prevents consequential multiple steam generator tube ruptures following a main steam line break event.
Relatively minor modifications to door opening could result in Modifications to lessen                                                                                                                                  lower flow to the Lower impact of flood that                                                                                  Potentially impact of internal flooding                                                                                                                              dumbwaiter. Specific 160                                    propagates through the                                                             <$50K       Expert Panel Cost-path through Control Building                                                                                                                            benefit could not be dumbwaiter                                                                                                  Beneficial dumbwaiter.                                                                                                                                              calculated but SAMA item is judged to be low cost and therefore potentially cost beneficial.
Improvements to PORV performance that will lower     Decrease in risk due to              0.46%          PORVs do not fail to                                    Not Cost-161                                                                   0.85%          PORV                         $18K   >$100K 0.24% Expert Panel              Cost will exceed benefit.
the probability of failure to   PORV failing to open.                                      open                                             Beneficial open.
Install a large volume EDG      Allows transfer of EDF fuel Potentially  Wolf Creek estimated cost fuel oil tank at an elevation   oil to the EDG day tanks on                         No EDG fuel pump 162                                                                   1.14% 7.60%  EDGFUEL                       $124K    $150K 7.11%  Wolf Creek  Cost-        of $150K is less than the greater than the EDG fuel oil   failure of the fuel oil                                   failures Beneficial   potential benefit.
day tanks.                      transfer pumps.
Lower risk due to failures in Improve feedwater check         which feedwater check                                Feedwater Check Not Cost-163    valve reliability to reduce     valves fail to open and        5.52% 2.05%    FW02  Valves do not fail to $127K   >$500K 2.23% Expert Panel              Cost will exceed benefit.
Beneficial probability of failure to open. allow feeding of the steam                                 open generators.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                       Page 70 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                                    % Red.
                                                                     % Red.         SAMA       SAMA Case                       % Red SAMA       Potential Improvement                Discussion                 In OS                               Benefit  Cost        Cost Basis    Evaluation    Basis for Evaluation In CDF         Case        Description                      IN Number                                                                      Dose OECR Provide the capability to       Provide backup to ESW in     5.62%                AEPS power to SW                                       Not Cost-164    power the normal service        conditions with power only         7.64%   SW03                        $191K   >$500K 6.37% Expert Panel             Cost will exceed benefit.
pumps                                           Beneficial water pumps from AEPS.          available from AEPS.
Increase the size of the        Ensure a supply of makeup RWST does not                                        Not Cost-171    RWST or otherwise improve       water is available from the  0.68% 0.13%  LOCA04                        $13K   >$100K 0.07% Expert Panel             Cost will exceed benefit.
deplete                                         Beneficial the availability of the RWST    RWST.
Implementation of Improvements to UHS                                                                UHS cooling tower                                     Potentially temporary ventilation or Improve availability or            4.75%
178    cooling tower electrical room                                3.29%        HVAC02 electrical room HVAC  $113K   <$100K 3.82% Expert Panel Cost        opening of doors will be a mitigate loss of HVAC.               %
HVAC.                                                                                 does not fail.                                     Beneficial  lower cost than the calculated benefit.
Modify procedures such that                                                                                                                          Implementation of Prevents possible thermally                       Reduced probability the water loop seals in the                                                                                                              Potentially procedure change will be induced steam generator                           of thermally induced 179    RCS cold legs are not                                        0.15% 3.18%   RAI7a                        $63K   <$100K 4.46% Expert Panel Cost        lower cost than benefit, tube rupture following core                      steam generator tube cleared following core                                                                                                                   Beneficial  especially if 95% CDF damage.                                                  failure damage.                                                                                                                                              benefit is considered.
SAMA considered Install lower amperage fuses                                                                                                                         potentially cost beneficial for various 14 AWG control                                                                                                                           without benefit or cost circuits in the MCR. The                                                                                                                 Potentially determination since the 180    majority of the modification    Reduced fire risk.                                                                                       Cost        NFPA 805 license centers around the trip circuit                                                                                                          Beneficial  amendment request fuses on NB, NG, PA, PB,                                                                                                                             committed to performing and PG system breakers.                                                                                                                              the modification.
SAMA considered potentially cost beneficial without benefit or cost Install redundant fuses and                                                                                                                          determination since the Potentially isolation switches for MCR                                                                                                                           NFPA 805 license 181                                    Reduced fire risk.                                                                                       Cost evacuation procedure OTO-                                                                                                                            amendment request Beneficial ZZ-00001.                                                                                                                                            committed to performing the modification.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                    Page 71 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                                  % Red.
                                                                   % Red.         SAMA      SAMA Case                       % Red SAMA       Potential Improvement                Discussion               In OS                              Benefit   Cost       Cost Basis    Evaluation     Basis for Evaluation In CDF          Case     Description                       IN Number                                                                    Dose OECR To protect against multiple spurious operation scenarios,                                                                                                                     SAMA considered cable runs will be changed to                                                                                                                     potentially cost beneficial run a single wire in a                                                                                                                            without benefit or cost protected metal jacket such                                                                                                                       determination since the Potentially that spurious valve opening                                                                                                                       NFPA 805 license 182                                  Reduced fire risk.                                                                                      Cost due to a hot short affecting                                                                                                                      amendment request Beneficial the valve control circuit is                                                                                                                      committed to performing eliminated for the fire area.                                                                                                                     the modification.
This modification will be implemented in multiple fire areas.
SAMA considered Quick response sprinkler                                                                                                                          potentially cost beneficial heads in cable chases A-11,                                                                                                                       without benefit or cost C-30, and C-31 will be                                                                                                                Potentially determination since the 183    modified to be in accordance Reduced fire risk.                                                                                       Cost        NFPA 805 license with the applicable                                                                                                                   Beneficial  amendment request requirements of NFPA 13-                                                                                                                          committed to performing 1976 edition.                                                                                                                                     the modification.
Cost is for installation of redundant instrumentation system and would likely be Improvements in the More reliable main steam                         Steam Line Isolation                                   Not Cost-   much higher. Procedure 184    reliability of the Steam Line                              0.59% 0.95%    SLIS                       $28K   >$500K 1.06% Expert Panel line isolation.                                  System does not fail                                   Beneficial  and training already direct Isolation automatic signal.
operators to manually back up failed automatic actuations.
Automate initiation of CCW    More reliable than manual                        Evaluate automating                                    Potentially 185    flow to the RHR heat          initiation of flow to RHR    3.53% 0.14%    HEP   CCW flow to RHR      $62K    $200K 0.11% Expert Panel Cost exchangers.                   HX.                                                      HXs                                            Beneficial Develop a procedure and obtain equipment to provide   Backup cooling water if ESW/SW is lost                                   Fire water available                                   Not Cost-   Ability to do this will require 186    a temporary hookup of fire                                 0.04% 0.05%  FWCCW                         $1K    >$1M  0.04% Expert Panel to cool CCW HX                                       Beneficial  larger fire pumps.
water as a replacement for ESW Install modification to power Another source of backup                                                                                            Already installed spare Reduce the                                        Potentially the normal charging pump      power to the NCP in cases                                                                                           circuit breaker, 187                                                               4.07% 7.63%  SBOMOD  frequency of SBO    $174K    $350K 7.03% Expert Panel Cost from an existing spare        of station blackout or loss                                                                                         implementation requires sequences.                                        Beneficial breaker from the AEPS.        of service water                                                                                                    power and control cables.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1                                                                                                                  Page 72 of 86 Table 7-1. Callaway Plant 1 Phase II SAMA Analysis Callaway                                                                    % Red.
                                                                     % Red.          SAMA     SAMA Case                   % Red SAMA       Potential Improvement                Discussion                 In OS                           Benefit  Cost       Cost Basis    Evaluation     Basis for Evaluation In CDF          Case     Description                   IN Number                                                                      Dose OECR Another source of backup Install a permanent, power to the NCP, DC dedicated generator for the                                                                                                                     AEPS was installed with a power (pump/valve control NCP, and a motor-driven                                                              Reduce the                                     Potentially spare breaker and and SG level 188    AFW pump and battery                                         4.28% 7.63%  SBOMOD2 frequency of SBO $182K   $400K 7.38% Expert Panel Cost        expansion capability that instrumentation), and charger to address SBO                                                               sequences.                                     Beneficial  could be used to supply power to an AFW pump in events in which the TD AFW                                                                                                                      various equipment.
cases of station blackout or pump is unavailable.
loss of service water Perform analysis to determine if it is possible to modify current plant doors to withstand higher flood                                                                                                                          Installation of modified heights. Either perform                                                                                                                         doors or modification of Callaway    Potentially modifications to install       Reduction in risk due to                                                                                         flooding analysis will result 189                                                                                                                              Plant     Cost improved doors or revise       internal flooding.                                                                                               in lower flooding risk.
Management Beneficial flooding analysis to                                                                                                                            Analysis is currently in incorporate results that doors                                                                                                                  progress.
will withstand higher flooding heights without propagating the flood.
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.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1 Page 73 of 86 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway                                                                                           Benefit at Benefit at          Benefit SAMA                               Benefit SAMA              Potential Improvement                    Discussion                     Benefit  3% Disc   Realistic           at 95%    Cost  Cost Basis  Evaluation    Basis for Evaluation Case                               at 33yrs Number                                                                                                Rate    Disc Rate            CDF Provide additional DC battery          Extended DC power availability                                                                                Not Cost-   Cost will exceed 1                                                                               NOSBO  $360K    $588K      $325K     $512K    $761K    >$1M  Expert Panel capacity.                              during an SBO.                                                                                                Beneficial  benefit.
Replace lead-acid batteries with fuel  Extended DC power availability                                                                                Not Cost-   Cost will exceed 2                                                                               NOSBO  $360K    $588K      $325K     $512K    $761K    >$1M  Expert Panel cells.                                 during an SBO.                                                                                                Beneficial  benefit.
Improved availability of DC power                                                                             Not Cost-   Cost will exceed 5    Provide DC bus cross-ties.                                                   DC01   $1K      $1K        $1K       $1K     $1K    >$199K Expert Panel system.                                                                                                       Beneficial  benefit.
Physical cross-tie exists, but there is no analysis or procedures to allow its use except in specific outage Potentially conditions. Cost is to Increased availability of on-site 11    Improve 4.16-kV bus cross-tie ability.                                       4kv2  $13K     $20K       $12K      $17K    $27K    <$100K Expert Panel   Cost-     develop procedures AC power.
Beneficial  and analysis to allow use of the cross-tie.
Benefit calculated is under-estimated since it was evaluated for only SBO sequences.
Install tornado protection on gas      Increased availability of on-site                                                                             Not Cost-   Cost will exceed 15                                                                                LOSP1  $91K    $144K       $82K     $125K    $192K   >$500K Expert Panel turbine generator.                     AC power.                                                                                                     Beneficial  benefit.
Cost will exceed benefit. Previous Improved off-site power reliability                                                                           Not Cost-   SAMA submittals 24    Bury off-site power lines.                                                 NOLOSP $1.2M     $2.0M     $1.1M     $1.7M    $2.6M    >$3M  Expert Panel during severe weather.                                                                                        Beneficial  have estimated approximately $1M per mile.
Install an independent active or Improved prevention of core melt                                                                              Not Cost-   Cost will exceed 25    passive high pressure injection                                            LOCA12 $616K    $979K      $557K      $850    $1.3M   >$1.5M Expert Panel sequences.                                                                                                    Beneficial  benefit.
system.
Provide an additional high pressure    Reduced frequency of core melt Not Cost-   Cost will exceed 26    injection pump with independent        from small LOCA and SBO             LOCA12 $616K    $979K      $557K      $850    $1.3M   >$1.5M Expert Panel Beneficial  benefit.
diesel.                                sequences.
Add a diverse low pressure injection                                                                                                                 Not Cost-   Cost will exceed 28                                           Improved injection capability.      LOCA03  $65K    $111K       $58K      $97K    $137K    >$1M  Expert Panel system.                                                                                                                                              Beneficial  benefit.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1 Page 74 of 86 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway                                                                                           Benefit at Benefit at          Benefit SAMA                               Benefit SAMA              Potential Improvement                       Discussion                  Benefit  3% Disc   Realistic           at 95%    Cost  Cost Basis    Evaluation   Basis for Evaluation Case                               at 33yrs Number                                                                                               Rate     Disc Rate            CDF SAMA is judged to be low cost, but analysis is needed to determine impacts of injection of non-Potentially borated water to Provide capability for alternate                                                                                                                                  RCS.
29                                            Improved injection capability.                                                                                   Cost-injection via diesel-driven fire pump.
Beneficial Expert Panel judged this SAMA to be potentially cost-beneficial without determining an actual benefit or cost.
Reduced common cause failure of the safety injection system. This SAMA was originally intended for Replace two of the four electric safety the Westinghouse-CE System                                                                                   Not Cost-    Cost will exceed 39    injection pumps with diesel-powered                                        LOCA12 $616K    $979K      $557K     $850K    $1.3M   >$1.5M Expert Panel 80+, which has four trains of                                                                                Beneficial   benefit.
pumps.
safety injection. However, the intent of this SAMA is to provide diversity within the high- and l Allows low pressure emergency core cooling system injection in Create a reactor coolant                                                   DEPRES                                                                    Not Cost-    Cost will exceed 41                                            the event of small LOCA and                $12K     $20K       $11K      $17K    $25K    >$500K Expert Panel depressurization system.                                                       S                                                                     Beneficial   benefit.
high-pressure safety injection failure.
Add redundant DC control power for                                                                                                                   Not Cost-    Cost will exceed 43                                            Increased availability of SW.       SW01    $1K      $2K        $1K       $2K     $3K    >$100K Expert Panel SW pumps.                                                                                                                                            Beneficial   benefit.
Increased availability of cooling                                                                            Not Cost-    Cost will exceed 46    Add a service water pump.                                                   SW02  $636K     $1M       $575K     $879K    $1.3M    >$5M  Expert Panel water.                                                                                                       Beneficial   benefit.
Increased time before charging Increase charging pump lube oil         pump failure due to lube oil                                                                                 Not Cost-    Cost will exceed 54                                                                                CHG01   $4K      $7K        $4K       $6K     $9K    >$100K Expert Panel capacity.                               overheating in loss of cooling                                                                               Beneficial   benefit.
water sequences.
Cost will exceed benefit. Previous investigation into Reduced frequency of core                                                                                                 installing such a Install an independent reactor coolant damage from loss of component                                                                                Not Cost-    system concluded 55    pump seal injection system, with                                          RCPLOCA $94K     $168K       $85K     $148K    $198K    >$1M  Expert Panel cooling water, service water, or                                                                             Beneficial   that operators did not dedicated diesel.
station blackout.                                                                                                         have sufficient time to place the system in service prior to seal damage.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1 Page 75 of 86 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway                                                                                            Benefit at Benefit at          Benefit SAMA                                Benefit SAMA              Potential Improvement                     Discussion                     Benefit  3% Disc   Realistic           at 95%    Cost  Cost Basis    Evaluation   Basis for Evaluation Case                               at 33yrs Number                                                                                                Rate     Disc Rate            CDF Reduced frequency of core Install an independent reactor coolant damage from loss of component                                                                                  Not Cost-    Cost will exceed 56    pump seal injection system, without                                        RCPLOCA $94K     $168K       $85K     $148K    $198K   >$500K Expert Panel cooling water or service water, but                                                                            Beneficial   benefit.
dedicated diesel.
not a station blackout.
Install improved reactor coolant pump Reduced likelihood of reactor                                                                                   Not Cost-    Cost will exceed 58                                                                               RCPLOCA $94K     $168K       $85K     $148K    $198K    >$3M seals.                                 coolant pump seal LOCA.                                                                                        Beneficial   benefit.
Reduced likelihood of loss of Cost will Install an additional component        component cooling water leading                                                                                Not Cost-    Cost will exceed 59                                                                                CCW01   $59K    $106K       $53K      $93K    $124K    >$1M    exceed cooling water pump.                    to a reactor coolant pump seal                                                                                 Beneficial   benefit.
benefit LOCA.
The cost estimate is Implement procedure and hardware                                                                                                                                   for development of a modifications to allow manual                                                                                                                                      procedure and use of Potentially alignment of the fire water system to Improved ability to cool residual                                                                                            temporary 64                                                                               FWCCW2 $104K     $184K       $94K     $161K    $220K   <$150K Expert Panel Cost the component cooling water system, heat removal heat exchangers.                                                                                                  connections. Cost of Beneficial or install a component cooling water                                                                                                                               permanent header cross-tie.                                                                                                                                                  modification would be significantly higher.
Callaway Reduced chance of loss of main                                                                                 Not Cost-    Cost will exceed 65    Install a digital feed water upgrade.                                        FW01   $29K     $50K       $27K      $44K    $62K     $19M  Modification feed water following a plant trip.                                                                             Beneficial   benefit.
Costs Install a new condensate storage Increased availability of the                                                                                    Not Cost-  Cost will exceed 71    tank (auxiliary feedwater storage                                           CST01   $18K     $32K       $16K      $28K    $39K    >$2.5M Expert Panel auxiliary feedwater system.                                                                                      Beneficial benefit.
tank).
Provide a passive, secondary-side      Reduced potential for core Not Cost-  Cost will exceed 77    heat-rejection loop consisting of a    damage due to loss-of-feedwater       FW01   $29K     $50K       $27K      $44K    $62K     $>1M  Expert Panel Beneficial benefit.
condenser and heat sink.               events.
Replace existing pilot-operated relief valves with larger ones, such that     Increased probability of                                                                                         Not Cost-  Cost will exceed 79                                                                                 FB01   $79K    $133K       $72K     $117K    $168K   >$500K Expert Panel only one is required for successful    successful feed and bleed.                                                                                       Beneficial benefit.
feed and bleed.
Procedures to open doors or provide temporary ventilation may be cost Increased availability of                                                                                       Potentially beneficial for the Provide a redundant train or means 80                                           components dependent on room          HVAC  $156K    $259K      $141K     $227K    $331K   <$100K Expert Panel      Cost    EDGs, MDAFW of ventilation.
cooling.                                                                                                         Beneficial pumps, and charging pumps. Procedures for opening doors to the DC switchgear rooms exist.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1 Page 76 of 86 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway                                                                                           Benefit at Benefit at          Benefit SAMA                                Benefit SAMA              Potential Improvement                     Discussion                    Benefit  3% Disc   Realistic           at 95%    Cost  Cost Basis  Evaluation  Basis for Evaluation Case                                at 33yrs Number                                                                                                Rate    Disc Rate            CDF Replace service and instrument air compressors with more reliable         Elimination of instrument air Not Cost-  Cost will exceed 87    compressors which have self-           system dependence on service       INSTAIR   $2K      $3K       $2K       $$2K     $4K    >$500K Expert Panel Beneficial benefit.
contained air cooling by shaft driven  water cooling.
fans.
Install a passive containment spray    Improved containment spray                                                                                    Not Cost-  Cost will exceed 91                                                                              CONT01  $793K     $1.2M     $717K     $1.1M    $1.7M   >$10M  Expert Panel system.                                capability.                                                                                                   Beneficial benefit.
Increased decay heat removal Install an unfiltered, hardened        capability for non-ATWS events,                                                                               Not Cost-  Cost will exceed 93                                                                              CONT01  $793K     $1.2M     $717K     $1.1M    $1.7M    >$2M  Expert Panel containment vent.                      without scrubbing released fission                                                                            Beneficial benefit.
products.
Install a filtered containment vent to Increased decay heat removal remove decay heat. Option 1: Gravel    capability for non-ATWS events,                                                                               Not Cost-  Cost will exceed 94                                                                              CONT01  $793K     $1.2M     $717K     $1.1M    $1.7M    >$2M  Expert Panel Bed Filter; Option 2: Multiple Venturi with scrubbing of released fission                                                                            Beneficial benefit.
Scrubber                               products.
Reduced likelihood of hydrogen Provide post-accident containment                                                                                                                    Not Cost-  Cost will exceed 96                                           and carbon monoxide gas            H2BURN   $10K     $15K       $9K       $13K    $20K    >$100K Expert Panel inerting capability.                                                                                                                                 Beneficial benefit.
combustion.
Increased cooling and containment of molten core debris. Molten core debris Create a large concrete crucible with  escaping from the vessel is Not Cost-  Cost will exceed 97    heat removal potential to contain      contained within the crucible and    MAB                                                  >$10M  Expert Panel Beneficial benefit.
molten core debris.                    a water cooling mechanism cools the molten core in the crucible, preventing melt-through of the base mat.
Increased cooling and containment of molten core debris. Refractory material would be placed underneath the reactor vessel such that a molten core Create a core melt source reduction    falling on the material would melt                                                                            Not Cost-  Cost will exceed 98                                                                                MAB                                                  >$10M  Expert Panel system.                                and combine with the material.                                                                                Beneficial benefit.
Subsequent spreading and heat removal from the vitrified compound would be facilitated, and concrete attack would not occur.
Strengthen primary/secondary Reduced probability of                                                                                        Not Cost-  Cost will exceed 99    containment (e.g., add ribbing to                                         CONT01  $1.2M     $1.2M     $717K     $1.1M    $1.7M   >$10M  Expert Panel containment over-pressurization.                                                                              Beneficial benefit.
containment shell).
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1 Page 77 of 86 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway                                                                                         Benefit at Benefit at          Benefit SAMA                                Benefit SAMA              Potential Improvement                     Discussion                  Benefit  3% Disc   Realistic           at 95%    Cost  Cost Basis  Evaluation  Basis for Evaluation Case                               at 33yrs Number                                                                                              Rate    Disc Rate            CDF Increase depth of the concrete base mat or use an alternate concrete       Reduced probability of base mat                                                                             Not Cost-  Cost will exceed 100                                                                               MAB                                                 >$10M  Expert Panel material to ensure melt-through does   melt-through.                                                                                               Beneficial benefit.
not occur.
Construct a building to be connected Reduced probability of                                                                                      Not Cost-  Cost will exceed 102    to primary/secondary containment                                         CONT01 $1.2M     $1.2M     $717K     $1.1M    $1.7M   >$10M  Expert Panel containment over-pressurization.                                                                            Beneficial benefit.
and maintained at a vacuum.
Increased piping surveillance to identify leaks prior to complete                                                                            Not Cost-  Cost will exceed 104    Improve leak detection procedures.                                       LOCA05 $685K     $1.2M     $620K     $1.1M    $1.5M    >$2M  Expert Panel failure. Improved leak detection                                                                            Beneficial benefit.
would reduce LOCA frequency.
Install a redundant containment spray Increased containment heat                                                                                   Not Cost-  Cost will exceed 107                                                                             CONT01 $1.2M     $1.2M     $717K     $1.1M    $1.7M    >$2M  Expert Panel system.                                removal ability.                                                                                            Beneficial benefit.
Install an independent power supply to the hydrogen control system using either new batteries, a non-safety Reduced hydrogen detonation                                                                                 Not Cost-108    grade portable generator, existing                                       H2BURN  $10K     $15K       $9K       $13K    $20K    >$100K Expert Panel potential.                                                                                                  Beneficial station batteries, or existing AC/DC independent power supplies, such as the security system diesel.
Install a passive hydrogen control     Reduced hydrogen detonation                                                                                 Not Cost-  Cost will exceed 109                                                                             H2BURN  $10K     $15K       $9K       $13K    $20K    >$100M Expert Panel system.                                potential.                                                                                                  Beneficial benefit.
Erect a barrier that would provide enhanced protection of the Reduced probability of                                                                                      Not Cost-  Cost will exceed 110    containment walls (shell) from ejected                                     MAB                                                 >$10M  Expert Panel containment failure.                                                                                        Beneficial benefit.
core debris following a core melt scenario at high pressure.
Install additional pressure or leak Not Cost-  Cost will exceed 111    monitoring instruments for detection   Reduced ISLOCA frequency.         ISLOCA $123K    $179K      $111K     $154K    $259K   >$500K Expert Panel Beneficial benefit.
of ISLOCAs.
Add redundant and diverse limit        Reduced frequency of Not Cost-  Cost will exceed 112    switches to each containment           containment isolation failure and CONT02   $1K      $1K       $1K        $1K     $2K     >$1M  Expert Panel Beneficial benefit.
isolation valve.                       ISLOCAs.
Increase leak testing of valves in                                                                                                                 Not Cost-  Cost will exceed 113                                           Reduced ISLOCA frequency.         ISLOCA $123K    $179K      $111K     $154K    $259K    >$1M  Expert Panel ISLOCA paths.                                                                                                                                      Beneficial benefit.
Install self-actuating containment     Reduced frequency of isolation                                                                              Not Cost-  Cost will exceed 114                                                                             CONT02   $1K      $1K       $1K        $1K     $2K    >$500K Expert Panel isolation valves.                      failure.                                                                                                    Beneficial benefit.
Locate residual heat removal (RHR)     Reduced frequency of ISLOCA                                                                                 Not Cost-  Cost will exceed 115                                                                             ISLOCA $123K    $179K      $111K     $154K    $259K    >$1M  Expert Panel inside containment                     outside containment.                                                                                        Beneficial benefit.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1 Page 78 of 86 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway                                                                                           Benefit at Benefit at          Benefit SAMA                                Benefit SAMA              Potential Improvement                      Discussion                   Benefit  3% Disc   Realistic           at 95%   Cost  Cost Basis  Evaluation   Basis for Evaluation Case                               at 33yrs Number                                                                                                Rate    Disc Rate            CDF Cost would exceed benefit. Current plant Ensure ISLOCA releases are                                                                                                                                     design requires scrubbed. One method is to plug                                                                                                                                drains to be open.
Not Cost-116    drains in potential break areas so that Scrubbed ISLOCA releases.          ISLOCA $123K    $179K      $111K     $154K    $259K   >$1M  Expert Panel            Analysis and license Beneficial break point will be covered with                                                                                                                               changes required to water.                                                                                                                                                         implement are included in the cost estimate.
Institute a maintenance practice to perform a 100% inspection of steam Reduced frequency of steam                                                                                       Not Cost-  Cost will exceed 119                                                                              NOSGTR $1.4M      $2.1M     $1.2M     $1.8M    $2.9M   >$3M  Expert Panel generator tubes during each refueling generator tube ruptures.                                                                                      Beneficial benefit.
outage.
Increase the pressure capacity of the Eliminates release pathway to the secondary side so that a steam                                                                                                                      Not Cost-  Cost will exceed 121                                            environment following a steam     NOSGTR $1.4M      $2.1M     $1.2M     $1.8M    $2.9M   >$10M Expert Panel generator tube rupture would not                                                                                                                    Beneficial benefit.
generator tube rupture.
cause the relief valves to lift.
Install a redundant spray system to Enhanced depressurization depressurize the primary system                                                                                                                     Not Cost-  Cost will exceed 122                                            capabilities during steam         NOSGTR $1.4M      $2.1M     $1.2M     $1.8M    $2.9M   >$10M Expert Panel during a steam generator tube                                                                                                                       Beneficial benefit.
generator tube rupture.
rupture Route the discharge from the main steam safety valves through a Reduced consequences of a                                                                                   Not Cost-  Cost will exceed 125    structure where a water spray would                                       NOSGTR $1.4M      $2.1M     $1.2M     $1.8M    $2.9M   >$10M Expert Panel steam generator tube rupture.                                                                               Beneficial benefit.
condense the steam and remove most of the fission products.
Install a highly reliable (closed loop) steam generator shell-side heat         Reduced consequences of a                                                                                   Not Cost-  Cost will exceed 126                                                                              NOSGTR $1.4M      $2.1M     $1.2M     $1.8M    $2.9M   >$10M Expert Panel removal system that relies on natural   steam generator tube rupture.                                                                               Beneficial benefit.
circulation and stored water sources Cost will exceed benefit. Current containment design does not support this Vent main steam safety valves in        Reduced consequences of a                                                                                   Not Cost-  modification.
129                                                                              NOSGTR $1.4M      $2.1M     $1.2M     $1.8M    $2.9M   >$10M Expert Panel containment.                            steam generator tube rupture.                                                                               Beneficial Modifications to containment and associated analysis are included in the cost estimate.
Add an independent boron injection      Improved availability of boron                                                                              Not Cost-  Cost will exceed 130                                                                              NOATWS   $63K    $104K       $57K      $90K    $134K   >$1M  Expert Panel system.                                 injection during ATWS.                                                                                      Beneficial benefit.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1 Page 79 of 86 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway                                                                                                Benefit at Benefit at          Benefit SAMA                                Benefit SAMA               Potential Improvement                          Discussion                   Benefit  3% Disc   Realistic           at 95%    Cost  Cost Basis  Evaluation    Basis for Evaluation Case                               at 33yrs Number                                                                                                     Rate    Disc Rate            CDF Add a system of relief valves to Improved equipment availability                                                                                Not Cost-   Cost will exceed 131    prevent equipment damage from                                                  NOATWS   $63K    $104K       $57K      $90K    $134K    >$2M  Expert Panel after an ATWS.                                                                                                 Beneficial  benefit.
pressure spikes during an ATWS.
Install an ATWS sized filtered Increased ability to remove                                                                                    Not Cost-   Cost will exceed 133    containment vent to remove decay                                               NOATWS   $63K    $104K       $57K      $90K    $134K    >$1M  Expert Panel reactor heat from ATWS events.                                                                                 Beneficial  benefit heat.
Install motor generator set trip           Reduced frequency of core                                                                                      Not Cost-   Cost will exceed 136                                                                                   NOATWS   $63K    $104K       $57K      $90K    $134K   >$500K Expert Panel breakers in control room.                  damage due to an ATWS.                                                                                         Beneficial  benefit.
Reduced probability of a large Install digital large break LOCA                                                                                                                          Not Cost-   Cost will exceed 147                                               break LOCA (a leak before            LOCA05 $689K     $1.2M     $620K     $1.1M    $1.5M    >$5M  Expert Panel protection system.                                                                                                                                        Beneficial  benefit.
break).
Prevents secondary side depressurization should a steam line break occur upstream of the Install secondary side guard pipes up main steam isolation valves. Also                                                                                   Not Cost-   Cost will exceed 153                                                                                    NOSLB   $51K     $87K       $46K      $77K    $108K    >$1M  Expert Panel to the main steam isolation valves.        guards against or prevents                                                                                     Beneficial  benefit.
consequential multiple steam generator tube ruptures following a main steam line break event.
Relatively minor modifications to door opening could result in lower flow to the Modifications to lessen impact of          Lower impact of flood that                                                                                     Potentially dumbwaiter. Specific 160    internal flooding path through Control propagates through the                                                                         <$50K  Expert Panel   Cost-     benefit could not be Building dumbwaiter.                       dumbwaiter                                                                                                     Beneficial  calculated but SAMA item is judged to be low cost and therefore potentially cost beneficial.
Improvements to PORV performance Decrease in risk due to PORV                                                                                   Not Cost-   Cost will exceed 161    that will lower the probability of failure                                       PORV   $18K     $32K       $16K      $28K    $39K    >$100K Expert Panel failing to open.                                                                                               Beneficial  benefit.
to open.
Wolf Creek estimated Install a large volume EDG fuel oil        Allows transfer of EDF fuel oil to                                                                             Potentially cost of $150K is less 162    tank at an elevation greater than the      the EDG day tanks on failure of     EDGFUEL $124K    $131K      $113K     $156K    $263K    $150K  Wolf Creek    Cost-than the potential EDG fuel oil day tanks.                    the fuel oil transfer pumps.                                                                                   Beneficial benefit.
Lower risk due to failures in which Improve feedwater check valve feedwater check valves fail to                                                                                 Not Cost-   Cost will exceed 163    reliability to reduce probability of                                             FW02  $127K    $218K      $115K     $191K    $270K   >$500K Expert Panel open and allow feeding of the                                                                                  Beneficial  benefit.
failure to open.
steam generators.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1 Page 80 of 86 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway                                                                                        Benefit at Benefit at          Benefit SAMA                                Benefit SAMA              Potential Improvement                     Discussion                 Benefit  3% Disc   Realistic           at 95%   Cost   Cost Basis  Evaluation    Basis for Evaluation Case                               at 33yrs Number                                                                                            Rate     Disc Rate            CDF Provide the capability to power the    Provide backup to ESW in
                                                                                        $1191                                                              Not Cost-   Cost will exceed 164    normal service water pumps from        conditions with power only        SW03           $307K      $172K     $267K    $403K   >$500K Expert Panel K                                                                Beneficial  benefit.
AEPS.                                  available from AEPS.
Increase the size of the RWST or Ensure a supply of makeup water                                                                            Not Cost-   Cost will exceed 171    otherwise improve the availability of                                   LOCA04 $13K      $23K       $12K      $20K    $27K    >$100K Expert Panel is available from the RWST.                                                                                Beneficial  benefit.
the RWST Implementation of temporary ventilation Potentially Improvements to UHS cooling tower      Improve availability or mitigate                                                                                       or opening of doors 178                                                                            HVAC02 $113K    $181K      $102K     $158K    $239K   <$100K Expert Panel   Cost electrical room HVAC.                  loss of HVAC.                                                                                                          will be a lower cost Beneficial than the calculated benefit.
Implementation of procedure change Modify procedures such that the Prevents possible thermally                                                                                Potentially will be lower cost water loop seals in the RCS cold legs 179                                           induced steam generator tube      RAI7a $63K      $87K       $57K      $75K    $134K   <$100K Expert Panel   Cost      than benefit, are not cleared following core rupture following core damage.                                                                             Beneficial  especially if 95%
damage.
CDF benefit is considered.
SAMA considered potentially cost Install lower amperage fuses for                                                                                                                              beneficial without various 14 AWG control circuits in the                                                                                                                        benefit or cost Potentially MCR. The majority of the                                                                                                                                      determination since 180                                           Reduced fire risk.                                                                                           Cost modification centers around the trip                                                                                                                          the NFPA 805 license Beneficial circuit fuses on NB, NG, PA, PB, and                                                                                                                          amendment request PG system breakers.                                                                                                                                           committed to performing the modification.
SAMA considered potentially cost beneficial without benefit or cost Install redundant fuses and isolation                                                                                                             Potentially determination since 181    switches for MCR evacuation            Reduced fire risk.                                                                                           Cost the NFPA 805 license procedure OTO-ZZ-00001.                                                                                                                           Beneficial amendment request committed to performing the modification.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1 Page 81 of 86 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway                                                                                            Benefit at Benefit at          Benefit SAMA                                Benefit SAMA             Potential Improvement                           Discussion                Benefit  3% Disc   Realistic           at 95%    Cost  Cost Basis  Evaluation     Basis for Evaluation Case                               at 33yrs Number                                                                                                Rate     Disc Rate            CDF SAMA considered To protect against multiple spurious potentially cost operation scenarios, cable runs will beneficial without be changed to run a single wire in a benefit or cost protected metal jacket such that                                                                                                                      Potentially determination since 182    spurious valve opening due to a hot       Reduced fire risk.                                                                                            Cost the NFPA 805 license short affecting the valve control circuit                                                                                                             Beneficial amendment request is eliminated for the fire area. This committed to modification will be implemented in performing the multiple fire areas.
modification.
SAMA considered potentially cost beneficial without Quick response sprinkler heads in benefit or cost cable chases A-11, C-30, and C-31                                                                                                                     Potentially determination since 183    will be modified to be in accordance      Reduced fire risk.                                                                                            Cost the NFPA 805 license with the applicable requirements of                                                                                                                   Beneficial amendment request NFPA 13-1976 edition.
committed to performing the modification.
Cost is for installation of redundant instrumentation system and would Improvements in the reliability of the More reliable main steam line                                                                               Not Cost-   likely be much higher.
184    Steam Line Isolation automatic                                                SLIS $28K      $40K       $23K      $35K    $55K    >$500K Expert Panel isolation.                                                                                                  Beneficial  Procedure and signal.
training already direct operators to manually back up failed automatic actuations.
Potentially Automate initiation of CCW flow to        More reliable than manual 185                                                                                  HEP  $62K     $112K       $56K      $99K    $132K   >$200K Expert Panel   Cost the RHR heat exchangers.                  initiation of flow to RHR HX.
Beneficial Develop a procedure and obtain equipment to provide a temporary                                                                                                                                  Ability to do this will Backup method of removing                                                                                    Not Cost 186    hookup of fire water to the RHR heat                                        FWCCW   $1K       $2K        $1K       $2K     $2K     >$1M  Expert Panel             require larger fire decay heat if CCW is lost.                                                                                  Beneficial exchangers to use as a backup to                                                                                                                                  pumps CCW for removing decay heat.
Already installed Install modification to power the Another source of backup power                                                                              Potentially spare circuit breaker, normal charging pump from an 187                                              to the NCP in cases of station    SBOMOD $174K    $272K      $157K     $236K    $367K    $350K Expert Panel   Cost      implementation existing spare breaker from the blackout or loss of service water                                                                           Beneficial  requires power and AEPS.
control cables.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013 Enclosure 1 Page 82 of 86 Table 8-1. Callaway Plant Sensitivity Evaluation Callaway                                                                                         Benefit at Benefit at          Benefit SAMA                                Benefit SAMA              Potential Improvement                      Discussion                 Benefit  3% Disc   Realistic           at 95%   Cost  Cost Basis  Evaluation    Basis for Evaluation Case                               at 33yrs Number                                                                                             Rate     Disc Rate            CDF Install a permanent, dedicated          Another source of backup power                                                                                        AEPS was installed generator for the NCP, and a motor-     to the NCP, DC power                                                                                                  with a spare breaker Potentially driven AFW pump and battery             (pump/valve control and SG level SBOMOD                                                                               and expansion 188                                                                                    $182K    $285K      $165K     $247K    $385K   $400K Expert Panel   Cost charger to address SBO events in        instrumentation), and power to an   2                                                                                 capability that could Beneficial which the TD AFW pump is                AFW pump in cases of station                                                                                          be used to supply unavailable.                            blackout or loss of service water                                                                                     various equipment.
Perform analysis to determine if it is                                                                                                                        Installation of 189    possible to modify current plant doors                                                                                                                        modified doors or to withstand higher flood heights.                                                                                                                            modification of Callaway    Potentially Either perform modifications to install Reduction in risk due to internal                                                                                     flooding analysis will Plant       Cost improved doors or revise flooding       flooding.                                                                                                             result in lower Management   Beneficial analysis to incorporate results that                                                                                                                          flooding risk.
doors will withstand higher flooding                                                                                                                          Analysis is currently heights without propagating the flood.                                                                                                                        in progress.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                Page 83 of 86 Table 9-1. Callaway Plant Potentially Cost Beneficial SAMAs Callaway SAMA Number       Potential Improvement               Discussion           Additional Discussion 11     Improve 4.16-kV bus           Increased availability of  Physical cross-tie exists, cross-tie ability.            on-site AC power.          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        Improved injection         Currently being alternate injection via       capability.                evaluated by plant diesel-driven fire pump.                                 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       Improved ability to cool   Cost based on hardware modifications to     residual heat removal heat development of allow manual alignment of     exchangers.                procedure for temporary the fire water system to the                             hookup of fire water to component cooling water                                  CCW heat exchangers.
system, or install a                                     Cost of permanent component cooling water                                  modification would be header cross-tie.                                        much greater.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                  Page 84 of 86 Table 9-1. Callaway Plant Potentially Cost Beneficial SAMAs Callaway SAMA Number        Potential Improvement               Discussion          Additional Discussion 80     Provide a redundant train     Increased availability of   Procedures to open or means of ventilation.      components dependent on     doors or provide room cooling.               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       Lower impact of flood that impact of internal flooding   propagates through the path through Control          dumbwaiter Building dumbwaiter.
162     Install a large volume EDG    Allows transfer of EDG fuel fuel oil tank at an elevation oil to the EDG day tanks greater than the EDG fuel     on failure of the fuel oil oil day tanks.                transfer pumps.
178     Improvements to UHS           Improve availability or           Implementation of cooling tower electrical      mitigate loss of HVAC.       temporary ventilation or room HVAC.                                                 opening of doors will be a lower cost than the calculated benefit.
179     Modify procedures such        Prevents possible                 Implementation of that the water loop seals in  thermally induced steam       procedure change will the RCS cold legs are not     generator tube rupture           be lower cost than cleared following core        following core damage.         benefit, especially if damage.                                                       95% CDF benefit is considered.
180     Install lower amperage        Reduced fire risk.               SAMA considered fuses for various 14 AWG                                         potentially cost control circuits in the MCR.                              beneficial without benefit The majority of the                                         or cost determination modification centers                                         since the NFPA 805 around the trip circuit fuses                                 license amendment on NB, NG, PA, PB, and                                      request committed to PG system breakers.                                               performing the modification.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                 Page 85 of 86 Table 9-1. Callaway Plant Potentially Cost Beneficial SAMAs Callaway SAMA Number        Potential Improvement               Discussion          Additional Discussion 181     Install redundant fuses and   Reduced fire risk.              SAMA considered isolation switches for MCR                                      potentially cost evacuation procedure                                      beneficial without benefit OTO-ZZ-00001.                                               or cost determination since the NFPA 805 license amendment request committed to performing the modification.
182     To protect against multiple   Reduced fire risk.              SAMA considered spurious operation                                              potentially cost scenarios, cable runs will                                beneficial without benefit be changed to run a single                                  or cost determination wire in a protected metal                                    since the NFPA 805 jacket such that spurious                                    license amendment valve opening due to a hot                                  request committed to short affecting the valve                                       performing the control circuit is eliminated                                    modification.
for the fire area. This modification will be implemented in multiple fire areas.
183     Quick response sprinkler      Reduced fire risk.              SAMA considered heads in cable chases A-                                        potentially cost 11, C-30, and C-31 will be                                beneficial without benefit modified to be in                                           or cost determination accordance with the                                          since the NFPA 805 applicable requirements of                                   license amendment NFPA 13-1976 edition.                                       request committed to performing the modification.
185     Automate initiation of CCW    More reliable than manual flow to the RHR heat          initiation of flow to RHR exchangers.                   HX.
187     Install modification to       Another source of backup    Already installed spare power the normal charging     power to the NCP in cases   circuit breaker, pump from an existing         of station blackout or loss implementation requires spare breaker from the        of service water            power and control AEPS.                                                     cables.
Callaway Plant Unit 1 Environmental Report for License Renewal

ULNRC-05947 January 15, 2013                                                                                Page 86 of 86 Table 9-1. Callaway Plant Potentially Cost Beneficial SAMAs Callaway SAMA Number        Potential Improvement               Discussion          Additional Discussion 188     Install a permanent,           Another source of backup   AEPS was installed with dedicated generator for the    power to the NCP, DC       a spare breaker and NCP, and a motor-driven        power (pump/valve control  expansion capability that AFW pump and battery           and SG level               could be used to supply charger to address SBO         instrumentation), and      various equipment.
events in which the TD         power to an AFW pump in AFW pump is unavailable.       cases of station blackout or loss of service water 189           Perform analysis to        Reduction in risk due to  Installation of modified determine if it is possible to       internal flooding. doors or modification of modify current plant doors                                 flooding analysis will to withstand higher flood                                result in lower flooding heights. Either perform                                     risk. Analysis is modifications to install                                currently in progress.
improved doors or revise flooding analysis to incorporate results that doors will withstand higher flooding heights without propagating the flood.
Callaway Plant Unit 1 Environmental Report for License Renewal}}