ML18151A477

Summary of Facility Changes, Tests and Experiments and Summary of Commitment Changes

ML18151A477
Person / Time
Site:	Kewaunee
Issue date:	05/21/2018
From:	Yuen S Dominion Energy Kewaunee
To:	Document Control Desk, Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation
References
18-188
Download: ML18151A477 (17)

Text

~ Dominion Dominion Energy Kewaunee, Inc.

N490 Hwy 42, Kewaunee, WI 54216 p Energy 0 Web Address: www.dominionenergy.com MAY 2 1 2018 A TIN: Document Control Desk Serial No.18-188 U. S. Nuclear Regulatory Commission UC/RR/RO

.Washington, DC 20555-0001 Docket Nos.: 50-305, 72-64 License No.: DPR-43 DOMINION ENERGY KEWAUNEE, INC.

KEWAUNEE POWER STATION

SUMMARY

OF FACILITY CHANGES, TESTS AND EXPERIMENTS AND

SUMMARY

OF COMMITMENT CHANGES Pursuant to 10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2), a report containing a brief description of any changes, tests, and experiments, including a summary of the evaluation of each, must be submitted to the NRC at intervals not to exceed 24 months. Attachment 1 provides a summary description of Facility Changes, Tests and Experiments identified in 10 CFR 50.59 and 10 CFR 72.48 evaluations performed at the Kewaunee Power Station (KPS) during the last 24 months.

No commitment changes occurred during the last 24 months.

The enclosed summary encompasses all changes that occurred in both of the stated areas since our prior submittal dated May 23, 2016 (Reference 1).

If you have any questions or require additional information, please contact Mr. William Zipp, at 920-388-8842.

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S. J. Yuen Plant Manager, Kewaunee Power Station Commitments made by this letter: NONE

Reference:

1. Letter from S. J. Yuen (Dominion Energy Kewaunee, Inc.) to Document Control Desk (NRC),

"Summary of Facility Changes, Tests and Experiments and Summary of Commitment Changes," dated May 23, 2016.

Serial No.18-188 Page 2 of 2 cc: Regional Administrator, Region Ill U. S. Nuclear Regulatory Commission 2443 Warrenville Road, Suite 210 Lisle, IL 60532-4352 Mr. Ted H. Carter, Senior Project Manager U.S. Nuclear Regulatory Commission Two White Flint North, Mail Stop T-8F5 11555 Rockville Pike Rockville, MD 20852-2738 I'

1:

Serial No.18-188 ATTACHMENT 1

SUMMARY

OF FACILITY CHANGES, TESTS AND EXPERIMENTS AND

SUMMARY

OF COMMITMENT CHANGES KEWAUNEE POWER STATION DOMINION ENERGY KEWAUNEE, INC.

Serial No.18-188 Attachment 1 Page 1 of 14 50.59 Evaluations There were no 50.59 evaluations completed and implemented during this period.

72.48 Evaluations 72.48 Evaluation #2016-01-00 Activity Evaluated Revision of NAC International, MAGNASTOR Final Safety Analysis Report, per design change request 71160-FSAR-7D and 72.48 evaluation number NAC-15-MAG-022 Brief Description of Change MAGNASTOR FSAR Rev. 7 Section 3.5.1.4, TSC Handling Loads, was revised to update the TSC lift lug evaluation for handling conditions to reflect an increased load for supplemental support equipment, a reduced weld area, and an increased bearing area. The evaluation of the TSC lift lug was updated consistent with the governing evaluation as detailed in NAC calculation 71160-2015 Rev. 5.

Reason for Change The TSC lift lugs are evaluated for handling loads related to welding and closure operations, where the lugs are to support the weight of the lid and supplemental support equipment prior to the completion of welding the closure lid to the TSC shell. Once the closure lid is welded, no structural credit is taken for the lugs. The changes revise the TSC lift lug evaluation increasing the load supported by the lugs, increasing the bearing area between the lug and the closure lid, and reducing the lug to shell weld area. The increased load and reduced weld area have an adverse but acceptable effect on the performance of the lug as described in the FSAR (as updated). As demonstrated by the revised evaluation, the structu.ral capacity of the lug exceeds that required for the loading condition as the allowable stresses are not exceeded.

Summary of the Evaluation The changes do not result in more than a minimal increase in the frequency of occurrence of an accident previously evaluated in the FSAR (as updated) since the revised configuration is shown to meet the applicable NRC requirements and design standards detailed by the lift lug evaluation detailed in the FSAR (as updated)

The changes do not involve a departure from the design, fabrication, construction, testing and performance standards previously used for the MAGNASTOR storage system. The revised lift lug evaluation demonstrates the acceptability of the changes and does not adversely affect the loaded and welded TSC configuration. Therefore, the evaluation changes and increase loading permitted for welding equipment and supplemental shielding do no result in a more than minimal increase in the frequency of occurrence of a malfunction of a SCC as previously evaluated in the FSAR (as updated).

The changes to the lift lug evaluation demonstrate the configuration and loading meet all applicable design requirements. The changes do not affect the shielding or criticality evaluation presented in the FSAR (as updated). As such, the changes have no effect on the consequences of an accident of the MAGNASTOR system for normal operations, anticipated occurrences (off-normal events), or accident conditions.

The changes to the lift lug evaluation demonstrate the configuration and loading meet all

Serial No.18-188 Attachment 1 Page 2 of 14 applicable design requirements and do not affect the shielding or criticality evaluations presented in the FSAR (as updated). Additionally, the changes do not adversely affect the loaded and welded TSC configuration or portions of components important to the shielding performance of the system. As such, the changes do not result in more than a minimal increase in the consequences of a malfunction of an SSC important to safety previously evaluated in the FSAR as updated_.

The revised TSC lift lug evaluation, and corresponding lug configuration and permitted loading, has been shown to be acceptable meeting all applicable design requirements. Additionally, the revisions do not adversely affect the loaded and welded TSC configuration. Accordingly, the changes do not create a possibility for any credible new accidents that have not been previously evaluated in the FSAR (as updated).

The changes to the lift lug evaluation demonstrate the configuration and loading are acceptable meeting all applicable design requirements. Additionally, the revisions do not adversely affect the loaded and welded TSC configuration. Therefore, the changes do not increase the likelihood of any malfunction previously thought to be incredible to the point where it becomes as likely as the malfunctions considered in the FSAR (as updated).

No design basis limits for a fission product barrier are altered or exceeded as a result of the changes. The fission product barriers include the fuel cladding and the TSC confinement system.

The design basis limits for the fuel cladding and TSC confinement boundary, namely the allowable temperature and stresses are not altered.

The TSC lift lugs are evaluated for handling loads related to welding and closure operations, where the lugs are to support the weight of the lid and supplemental support equipment prior to the completion of welding the closure lid to the TSC shell. The activity makes changes to the values used in the evaluation of the lug to consider increased loading, an increased and more representative bearing area, and a slightly reduced weld area. Note that the evaluation methodology is not changed. The revised evaluation demonstrates the acceptability of the changes with a performance meeting all applicable design requirements.

Serial No.18-188 Attachment 1 Page 3 of 14 72.48 Evaluation #2016-02-00 Activity Evaluated Revision of NAC International, MAGNASTOR Final Safety Analysis Report, per design change request 71160-FSAR-71 and 72.48 evaluation number NAC-16-MAG-004

• Brief Description of Change .

Change the last two sentences of the Section 8.10.1 of the MAGNASTOR FSAR Rev. 7 to:

Fuel assemblies typically do not contain aluminum or carbon steel parts exposed to coolant/moderator or are in contact with non-fuel hardware, and therefore are not subject to significant gas generation or corrosion during prolonged water immersion (20-40 years). Carbon steel plenum springs, which are not normally exposed to water, may be used in some fuel designs.

Clad failure could expose the springs. Small quantities of uncoated exposed carbon steel are permitted in the system as discussed in Section 8.6.L. Thus, no adverse reactions occur with the control and nonfuel components over prolonged periods of dry storage.

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There are no aluminum or carbon steel fuel assembly parts, and no gas generation or corrosion occurs during prolonged water immersion (20 - 40 years). Thus, no adverse reactions occur with the control and nonfuel components over prolonged periods of dry storage.

Reason for Change The changes clarify that fuel assemblies with carbon steel plenum springs are acceptable contents for the MAGNASTOR system. The plenum springs provide positive contact of the fuel pellets within a fuel rod, allowing for differential thermal expansion and permitting void space at the top of the fuel rod. For storage conditions the plenum springs do not provide a credited safety function.

Uncoated carbon steel has the potential for a galvanic reaction when in contact with dissimilar metals with different corrosion potentials and in a conductive electrolyte solution (e.g., water). The carbon steel fuel basket is coated with electroless nickel to reduce the corrosion potential of the basket. Testing demonstrating the effectiveness of the electroless nickel coating for carbon steel identified that water turbidity was the primary concern with the presence of uncoated carbon steel and that there were no measurable indications of hydrogen generation during testing (NAC Document No. 910-9004A).

As described in the FSAR (as updated), vendor and Nuclear Regulatory Commission evaluations have concluded that combustible gases, primarily hydrogen, may be produced by a chemical reaction and/or radiolysis when aluminum components are immersed in spent fuel pool water. The evaluations further concluded that it is possible, at higher temperatures (above 150 - 160F), for the aluminum/water reaction to produce a hydrogen concentration in the TSC that approaches or exceeds the Lower Flammability Limi~ (LFL) for hydrogen of four percent. As described, it is therefore reasonable to conclude that small amounts of combustible gases, primarily hydrogen may be produced during TSC loading or unloading operations as a result. of a chemical reaction between the aluminum neutron absorber in the fuel basket and the spent fuel pool water.

Aluminum is a more anodic metal than carbon steel and for the MAGNASTOR basket is in contact with dissimilar metals (i.e., aluminum neutron absorber sheet secured to the nickel coated carbon steel fuel tube by the stainless steel retainer). Therefore, the inclusion of aluminum is more likely to lead to gas generation than carbon steel. As described in the FSAR (as updated), monitoring for levels of hydrogen approaching the Lower Flammability Limit (LFL) is performed during TSC

Serial No.18-188 Attachment 1 Page 4 of 14 closure lid root pass welding, and during closure lid weld removal operations in preparation for TSC unloading. If hydrogen levels exceed 60% of LFL (i.e., 2.4% hydrogen), these operations are stopped and corrective actions are taken until the hydrogen levels are reduced to acceptable levels.

Therefore, no adverse conditions, such as the ignition of flammable or explosive quantities of combustible gases, can result during any phase of TSC operations.

Accordingly, the clarification to permit fuel assemblies with carbon steel plenum springs does not significantly affect the material compatibilities described in the FSAR (as updated) as it relates to the design function of the system or during operations.

Summary of the Evaluation The changes do not result in more than a minimal increase in the frequency of occurrence of an accident previously evaluated in the FSAR (as updated) since the plenum springs do not provide a credited safety function and do not affect the ability of the system to meet the applicable NRC requirements and design standards detailed in the FSAR (as updated). Additionally, the monitoring of hydrogen levels during closure operations ensures that no adverse conditions, such as the ignition of flammable or explosive quantities of combustible gases, can result during any phase of TSC operations. Furthermore, once the TSC is vacuumed dried and backfilled with helium it becomes an inert environment with no significant potential for corrosion to occur.

The changes do not involve a departure from the design, fabrication, construction, testing and performance standards previously used for the MAGNASTOR storage system. The plenum springs do not provide a credited safety function and do not affect the ability of the system to meet the applicable NRC requirements and design standards detailed in the FSAR (as updated).

Additionally, the monitoring of hydrogen levels during closure operations ensures that no adverse conditions, such as the ignition of flammable or explosive quantities of combustible gases, can result during any phase of TSC operations. Furthermore, once the TSC is vacuumed dried and backfilled with helium it becomes an inert environment with no significant potential for corrosion to occur.

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The changes clarify that fuel assemblies with carbon steel plenum springs are acceptable contents for the MAGNASTOR system. The plenum springs provide positive contact of the fuel pellets within a fuel rod, allowing for differential thermal expansion and permitting void space at the top of the fuel rod. For storage conditions the plenum springs do not provide a credited safety function. Additionally, the mass involved represents an insignificant effect to the shielding evaluation. Therefore, the changes do not result in more than a minimal increase in the consequences of an accident of the MAGNASTOR system for normal operations, anticipated occurrences, off-normal events, or accident conditions.

The changes clarify that fuel assemblies with carbon steel plenum springs are acceptable contents for the MAGNASTOR system. *The plenum springs provide positive contact of the fuel pellets within a fuel rod, allowing for differential thermal expansion and permitting void space at the top of the fuel rod. For storage conditions the plenum springs do not provide a credited safety function. The mass involved represents an insignificant effect to the shielding evaluation. As such, the changes do not result in more than a minimal increase in the consequences of a malfunction of an SSC important to safety previously evaluated in the FSAR (as updated). Additionally, the monitoring of hydrogen levels during closure operations ensures that no adverse conditions, such as the ignition of flammable or explosive quantities of combustible gases, can result during any phase of TSC operations. Furthermore, once the TSC is vacuumed dried and backfilled with helium it becomes an inert environment with no significant potential for corrosion to occur.

For storage conditions the plenum springs do not provide a credited safety function and do not affect the ability of the system to meet the applicable NRC requirements and design standards

Serial No.18-188 Attachment 1 Page 5 of 14

• detailed in the FSAR (as updated). Additionally, the mass involved represents an insignificant effect to the shielding evaluation. Accordingly, the changes do not create a possibility for any credible new accidents that have not been previously evaluated in the FSAR (as updated).

For storage conditions the plenum springs do not provide a credited safety function and do not affect the ability of the system to meet the applicable NRC requirements and design standards detailed in the FSAR (as updated). The mass involved represents an insignificant effect to the shielding evaluation. Additionally, the monitoring of hydrogen levels during closure operations ensures that no adverse conditions, such as the ignition of flammable or explosive quantities of combustible gases, can result during any phase of TSC operations. Once the TSC is vacuumed dried and backfilled with helium it becomes an inert environment with no significant potential for corrosion to occur. Accordingly, the changes do not increase the likelihood of any malfunction previously thought to be incredible to the point where it becomes as likely as the malfunctions considered in the FSAR (as updated).

No design basis limits for a fission product barrier are altered or exceeded as a result of the changes. The fission product barriers include the fuel cladding and the TSC confinement system The design basis limits for the fuel cladding and TSC confinement boundary, namely the allowable temperature and stresses, are not altered.

The changes clarify that fuel assemblies with carbon steel plenum springs are acceptable contents for the MAGNASTOR system. The plenum springs provide positive contact of the fuel pellets within a fuel rod, allowing for differential thermal expansion and permitting void space at the top of the fuel rod. For storage conditions the plenum springs do not provide a credited safety function. Additionally, the mass involved represents an insignificant effect to the shielding evaluation. Therefore, the changes do not involve revising or replacing an evaluation methodology described in the cask licensing documents.

Serial No.18-188 Attachment 1 Page 6 of 14 72.48 Evaluation #2016-03-00 Activity Evaluated Revision of NAC International, MAGNASTOR Final Safety Analysis Report, per design change request 71160-FSAR-7J and 71160-FSAR-7M Brief Description of Change Changes to Revision 7 of the MAGNASTOR Final Safety Analysis Report were made to incorporate revised thermal contingency parameters and actions for canister processing and the supporting method of evaluation. The changes provide details of required actions related to canister processing operations associated with the use of the MTC/TSC during TSC lid placement, drainage, vacuum drying, helium backfill and transfer.

Reason for Change The application of NAC Calculation No. 71160-3020 (Rev. 18) involves the use of a revised method of evaluation within the thermal analysis model. Changes to the finite element model in Revision 11 of the calculation included discretization reductions which results in a more precise thermal response to the temperature transient inputs. When applied to TSC canister processing operations, these changes are less conservative because they increase the allowable time available without MTC annulus cooling prior to reaching associated temperature limits for the spent nuclear fuel and MAGNASTOR components. The application of these changes to the model were reviewed and approved by the NRC in Amendment 4 of MAGNASTOR CoC No. 1031.

Amendment 5 of MAGNASTOR CoC No. 1031 is currently applicable to the KPS dry cask loading activities. NRC approval of Amendment 5 was based on MAGNASTOR FSAR Revision 5 and Amendment 3 of MAGNASTOR CoC No. 1031, and therefore excluded consideration of the conditions previously approved by the NRC in Amendment 4 of MAGNASTOR CoC No. 1031.

MAGNASTOR FSAR changes described in DCR(L) 71160-FSAR-7 J included conditions that were not fully bounded for all design basis heat loads (::_35.5 kW) by the thermal analysis. The following conditions were corrected in DCR(L) 71160-FSAR-7M:

• Limitation of the application of a 4.5-hour ACWS allowed out of service time (AOT) for the initial drying cycle and a 4-hour AOT for subsequent cycles to heat loads .:::_30 kW (FSAR Section 4.9.2 and Section 9.1 ).

• Allowance for use of natural convective air cooling contingency (TSC within the MTC with shield

,,,i doors open) for heat loads .:::_20 kW for crane malfunctions which prevent completion of TSC transfer within the LCO 3.1.1 time limits.

Summary of the Evaluation Evaluation questions 1 through 7 were answered no based on the thermal analysis documented in NAC Calculation No. 71160-3020 (Rev. 18). The evaluation demonstrates that the fuel and TSC remain below the normal condition temperature limits, which are the bases for the limiting conditions for operation described in TS 3.1.1. and the supporting information contained in the FSAR which ensures that the applicable NRC requirements are maintained. These changes have L no impact on conditions associated with structure, system or component malfunctions, accident conditions or fission product barriers.

Evaluation question 8 was answered no because the changes to elements of the approved method of evaluation had been previously approved by NRC for the intended application.

Serial No.18-188 Attachment 1 Page 7 of 14 The evaluation concluded that the use of the revised elements of the method of evaluation approved by the NRC in Amendment 4, and the resulting allowed procedure changes, by a general license under Coe 1031, Amendment 5, did not require prior NRC approval.

Serial No.18-188 Attachment 1 Page 8 of 14 72.48 Evaluation #2017-01-00 Activity Evaluated Grinding an outer port cover on the closure lid of a transportable storage canister (TSC) to make it flush with the top of the TSC closure lid.

Brief Description of Change The outer port cover bowed during welding operations. To restore it to acceptable configuration the thickness was reduced by field grinding/machining. This configuration change was evaluated under NAC International evaluation number NAC-17-MAG-008.

Reason for Change During closure operations for a KPS TSC, it was identified that the as welded outer port cover extends beyond the top surface of the lid, which does not meet the requirement detailed in the design and license drawings. The outer port cover bowed during welding operations. Drawing specifications require the port cover, closure ring and the associated weld to be below the top surface of the lid. The drawings permit field grinding or machining of the port cover to aid fit-up to a minimum thickness as defined by ASME plate specifications. The resulting reduced cover thickness following grinding was less than ASME minimum thickness. The 72.48 evaluation was performed to disposition the adverse effect to the structural capacity and adverse yet insignificant effect to the shielding performance.

Summary of the Evaluation Evaluation questions 1 through 7 were answered no based on an evaluation performed as detailed in NAC Memorandum No. ED20170005 that shows the port cover meets required stress requirements. The resulting port cover configuration will have sufficient structural and shielding capacity for all conditions of storage described in the FSAR. The change does not alter the manner in which SSCs are operated and controlled, therefore no possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is created.

Evaluation question 8 was answered no because the effect of the reduced outer port cover thickness was evaluated using the same methodology as described in the FSAR.

Serial No.18-188 Attachment 1 Page 9 of 14 72.48 Evaluation #2017-02-00 Activity Evaluated The disposition of a neutron absorber retainer and exposed aluminum sheet in a fuel cell location of a transportable storage canister (TSC) damaged during fuel loading operations Brief Description of Change The upper corner of the neutron absorber retainer in the outer tube wall of a spent nuclear fuel cell in a TSC was damaged during fuel loading operations, exposing the top region of the aluminum plate up to the location of the two leading weld posts. This configuration change was evaluated under NAC International evaluation number NAC-17-MAG-016.

Reason for Change i

i. Damage to the neutron absorber retainer occurred during fuel loading operations. The location of the damaged retainer corresponds to a periphery fuel tube location in which an optional aluminum sheet is substituted for the neutron absorber. Inspection of the images of the damage showed insignificant effects to the aluminum sheet such that it will function as credited by the safety analysis described in the FSAR. Similarly, the weld posts and the retainer beyond the nearest weld posts are present and intact, and it is determined they will function as evaluated in the structural evaluation of the retainer. Evaluation demonstrates that stresses within the aluminum sheet remain t

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below the applicable stress allowables. Additionally, estimated free cell opening accounting for the deformation of the retainer is larger than the fuel assembly width, indicating sufficient clearance for fuel retrievability. Evaluation demonstrates the nonconforming condition of the neutron absorber retainer is sufficient for conditions of storage. Based on this, the decision was made to use-as-is.

The 72.48 evaluation was performed to determine whether the use-as-is decision for the adverse condition of the exposed aluminum sheet and damaged retainer required prior NRC approval.

Summary of the Evaluation Questions 1 through 7 were answered no based on NAC Memorandum No. ED20170046 which demonstrated the structural capacity of the nonconforming aluminum attachment is sufficient for all conditions of storage meeting all NRC requirements and analysis requirements as detailed by the safety evaluation. Additionally, the nonconformance does not affect the thermal, shielding and criticality analysis of the TSC. The calculated clearance of the loaded fuel assembly with the effective fuel cell opening, accounting for the deformation of the retained, demonstrates that the fuel can be retrieved from the canister.

• Question 8 was answered no because evaluation of the nonconforming condition uses hand calculations consistent with evaluations described in the FSAR and uses the same acceleration and temperatures considered in the structural evaluation of the neutron absorber retainer described in the FSAR. Therefore the evaluation of the nonconforming condition does not involve revising or replacing an evaluation methodology described in the cask licensing documents.

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Serial No.18-188 Attachment 1 Page 10 of 14 72.48 Evaluation #2017-03-00 Activity Evaluated Revision of NAC International, MAGNASTOR Loading Contingency Procedure for one-time-only use to permit resumption of the canister loading process following limited interruption of annulus cooling water system Brief Description of Change As currently written, the Loading Contingency Procedure requires that any interruption of annulus cooling water system (ACWS) during vacuum drying result in sequence resumption under technical specification LCO 3.1.1 Item 1.8. The procedure was changed to modify the normal sequence to permit resumption of canister loading sequence in accordance with LCO 3.1.1 Item 1A. following a short interruption of ACWS.

Reason for Change Technical Specifications LCO 3.1.1 outlines the time tables to which adherence must be maintained during canister processing. LCO 3.1.1 Item 1.A. is the operationally preferred path, as no helium dwell period is required following backfill. The LCO permits an alternative path in Item 1.8. which requires a period of cooling (dwell) time following backfill before the transfer operation may be commenced. From the technical conclusions available in NAC Calculation 71160-3020 Rev. 18, it is concluded that a short ACWS interruption would be accommodated with sufficient analytical and operational margin to allow use of LCO 3.1.1 Item 1.A. without challenging the peak fuel temperatures already assumed in the transient analysis, provided the vacuum drying time has been maintained.

Summary of the Evaluation Evaluation questions 1 through 7 were answered no based on a short ACWS interruption during the TSC vacuum drying phase under LCO 3.1.1 Item 1.A., as proposed in the evaluated activity, does not change the range of conditions structures, systems or components are exposed to in any way.

It will not challenge the analyzed fuel cladding temperature limits, thus remaining bounded by MAGNASTOR CoC 1031, Amendment 5 Technical Specifications 5.2.c and 5.2.f. As concluded in NAC Calculation 71160-3020 Rev. 18, the resulting fuel configurations and analyzed fuel cladding temperature limits remain fully bounded within the normal condition temperature limits already evaluated in the safety analyses.

Evaluation question 8 was answered no because the methods used to analyze the thermal transient are not within the scope of the proposed activity. The existing thermal analysis and conclusions stemming therefrom are referenced to identify existing analytical and operational margin that had not been previously credited in the stipulations identified in the MAGNASTOR FSAR. The procedural changes which utilize a fraction of the identified margin do not constitute a departure from the approved method of evaluation. Likewise, the application of the thermal analysis model described in NAC Calculation 7116-3020 (Rev. 18) as a basis for operational procedural changes for canister processing do not constitute a departure from *an approved method of evaluation.

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Serial No.18-188 Attachment 1 Page 11 of 14

• 72.48 Evaluation #2017-04-00 Activity Evaluated The disposition of a MAGNASTOR transportable canister (MTC) seal which became dislodged and subsequently trapped in a vertical concrete cask (VCC) during download of a transportable storage canister (TSC) into a VCC Brief Description of Change During transfer of a TSC from the MTC to its VCC (TSC, contained within the MTC, is lowered from the MTC into a VCC), the MTC lower seal dislodged from its groove and remains within the concrete cask. Prior to placement of the VCC lid, the seal could not be seen from above.

Therefore, it is expected that the seal is beneath, or partially beneath the TSC. This configuration change was evaluated under NAC International evaluation number NAC-17-MAG-01?-.

Reason for Change During transfer of a TSC to a VCC, the MTC lower seal dislodged from its groove and remains within the concrete cask. The seal is not visible from the top of the cask, indicating that it has fallen either beneath the concrete cask pedestal plate or is located between or partially between the top surface of the pedestal and the TSC bottom plate. The presence of the MTC seal within the cask cavity has the potential to increase the air flow resistance of the concrete cask passive coolirig system. The seal located between the TSC bottom plate and concrete cask pedestal will increase the contact resistance at the bearing interface between the TSC and pedestal. Additionally, the TSC sitting on the seal will create displacement limited (secondary) bending loads within the TSC bottom plate. These conditions were evaluated by NAC International (NAC Calculation 71160-3040 Appendices T and U, NAC Memorandum No. ED20170064) and dispositioned as use-as-is. The disposition results in permanent abandonment of the MTC seal in the VCC. Removal of the seal would represent a significant ALARA concern and a risk-adverse evolution relative to the minimal consequences associated with leaving the seal in the VCC. The 72.48 evaluation was performed to determine whether the permanent abandonment of the MTC seal in the VCC required prior NRC approval.

Summary of the Evaluation

,. Evaluation questions 1 through 7 were answered no based on NAC Calculation 71160-3040 Appendices T and U, which documents that the concrete cask was analyzed for blockage representing a MTC seal using the same methods used to qualify the performance of the concrete cask system as described in the FSAR. As demonstrated by the analysis results, the seal's potential to block air flow has an insignificant effect on thermal performance of the cask storage system. The potential that the seal is located beneath the TSC is evaluated for normal and accident conditions of storage in NAC Memorandum No. ED20170064. The evaluation demonstrates factors of safety that are enveloped or consistent with the minimum presented for the applicable loading condition. Also that presence of the seal would have an insignificant effect on the shielding performance of the concrete cask such that there is no effect to the maximum radiological consequence of accidents previously evaluated in the FSAR. Further the evaluation concludes the mass of the seal within the cask represents a limited material quantity in terms of fire contribution.

Evaluation question 8 was answered no because the concrete cask and TSC was analyzed for a blockage representing a MTC seal in NAC Calculation 71160-3040 Appendices T and U using the same methods used to qualify the performance of the concrete cask system as described in the FSAR. Additionally the seal is evaluated for normal and accident conditions of storage in NAC

Serial No.18-188 Attachment 1 Page 12 of 14 Memorandum No. ED20170064, using an evaluation methodology consistent with the previous evaluation methodology used for qualification of the TSC detailed in NAC Calculation 71160-2012.

Serial No.18-188 Attachment 1 Page 13 of 14 72.48 Evaluation #2017-05-00 Activity Evaluated Fire Protection Engineering Evaluation (FPEE) - 072 Rev. 4, Elimination of the Incipient Fire Brigade for Decommissioning at Kewaunee Power Station Brief Description of Change When operating, Kewaunee Power Station staffing included personnel trained and qualified to function as a 5 man Fire Brigade. More recently, it was determined, based upon the reduced risk presented by fire at a nuclear unit undergoing decommissioning, the brigade function could be performed by an incipient fire brigade. Finally, after all nuclear fuel had been permanently removed from both the reactor pressure vessel and the spent fuel pool (a condition enforced by regulation and a license condition) it was determined that the function heretofore performed by an incipient fire brigade could be adequately performed the offsite responders - specifically, the Kewaunee Fire Department. The replacement of the brigade function with support of off-site responders was determined to require an evaluation pursuant 10 CFR 72.48. The elimination of the brigade was determined to involve no adverse effects upon the Fire Protection Program, the program's ability to meet the regulatory requirements of 10 CFR 72.122( c), or the ability to extinguish a fire rapidly. And further concluded that the replacement of a brigade with the KFP would not prevent the

_station from protecting against a radiological release due to a fire nor prevent the engineered spent fuel storage containers from performing their function with off-site responders aiding in fire suppression activities.

Reason for Change To support decommissioning activities and posture, and consistent with sites undergoing decommissioning throughout the industry, the KPS fire brigade was eliminated.

Summary of the Evaluation The presence or absence of a fire fighting group has no effect upon the likelihood that a fire or any other accident will occur. The function of the brigade was to mitigate a particular accident if it were to occur. Therefore, this activity cannot result in more than a minimal increase in the frequency of an accident previously evaluated in the SAR.

The presence or absence of a fire fighting group has no effect upon the likelihood that an SSC important to safety will malfunction. If we conservatively consider the brigade to be, in this context, operating SSCs important to safety (i.e., firefighting equipment), it is clearly seen that the capabilities of the off-site responders (Kewaunee Fire Department (KFD)) that will be performing that activity going forward will meet or exceed the capabilities of the former brigade. Moreover, the KFD will be using similar equipment the failure and operation of which will continue to have no adverse effect upon 10 CFR 72 licensed SSCs important to safety, and will extinguish the fire rapidly consistent with the capabilities of the former fire brigade/crew. Therefore, this activity will not result in a more than a minimal increase in the likelihood of occurrence of a malfunction of a SSC important to safety previously evaluated in the SAR.

The capabilities of personnel operating firefighting equipment will not be diminished by this activity.

Only the timeliness of the response of firefighting personnel will be impacted. However, based upon the FPEE-072, Revision 4, the elimination of the brigade involves no adverse effects upon the Fire Protection Program or the program's ability to meet the regulatory requirements of 10 CFR 72.122(c). This change does not prevent the station from protecting against a radiological release due to a fire nor does this change prevent the engineered spent fuel storage containers from I performing their function while off-site responders aid in fire suppression activities. Moreover, the licensing basis Fire Accident Analyses performed to demonstrate that design limits of the SSCs I: important to safety would be met assume that the assumed volume of burning fuel would be I

Serial No.18-188 Attachment 1 Page 14 of 14 completed consumed by the fire (i.e., no credit given for extinguishing the fire). Therefore, the activity will not result in more than a minimal increase in the consequences of an accident previously evaluated in the SAR KFD will be using similar equipment the failure and operation of which will continue to have no adverse effect upon 10 CFR 72 licensed SSCs important to safety including their mitigating functions. Therefore, there is no expected change to the effects of a malfunction of an ISFSI SSC important to safety resulting from this activity. Therefore, this activity will not result in more than a minimal increase in the consequences of a malfunction of a SSC important to safety previously evaluated in the SAR The replacement of the brigade with the KFD is limited to which persons are performing virtually identical functions with very similar equipment. The replacement of personnel has no impact upon the malfunction of an SSC that could initiate an accident nor will the equipment used by the KFD in response to a fire have a new or different capacity to initiate an accident. Therefore, the activity will not create the possibility for an accident of a different type than any previously evaluated in the SAR The replacement of the brigade with the KFD is limited to which persons are performing virtually identical functions with very similar equipment. The replacement of personnel has no impact upon the malfunction of an SSC important to safety nor will the equipment used by the KFD in response to a fire have a new or different capacity to affect an SSC important to safety. Therefore, the activity will not create the possibility for a malfunction of a SSC important to safety with a different result than any previously evaluated in the SAR This activity does not affect any fission product barrier. Moreover, the licensing basis Fire Accident Analyses performed to demonstrate that design limits of the SSCs important to safety (including applicable barriers) would be met assume that the assumed volume of burning fuel would be completely consumed by the fire (i.e., no credit given for extinguishing the fire). Therefore, the results of those analyses cannot be impacted by this activity. Therefore, the activity will not result in a design basis limit for a fission product barrier as described in the SAR being exceeded or altered.

Although the credit for a brigade/crew extinguishing a fire rapidly is documented in the MAGNASTOR Fire Accident Analysis, the group of persons performing the specific task is not part of the calculation framework of the analysis. Therefore, it is not an element in the method of the

,, analysis and therefore constitutes neither a change to a method of evaluation, nor a departure from a method of evaluation. Therefore, this activity does not result in a departure from a method of evaluation described in the SAR used in establishing the design bases or in the safety analyses.

The evaluation concluded that none of the criteria in 10 CFR 72.48(c)(2)(i) through (viii) were met.

Commitment Change Evaluation Summary There were no commitment changes in this reporting period.