ML15254A050

Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 for the Yankee Nuclear Power Station Independent Spent Fuel Storage Installation

ML15254A050
Person / Time
Site:	Yankee Rowe
Issue date:	09/01/2015
From:	Beverly Smith Yankee Atomic Electric Co
To:	Document Control Desk, Division of Spent Fuel Management
References
BYR 2015-028
Download: ML15254A050 (14)

Text

YANEEATOMIC ELECTRIC COMPANY 49 Yankee Road, Rowe, Massachusetts 01367 September 1, 2015 BYR 2015-028 Re: 10 CFR 72.4 and 10 CFR 72.7 ATTN: Document Control Desk, Director, Division of Spent Fuel Management Office of Nuclear Material Safety and Safeguards U.S. Nuclear Regulatory Commission, Washington, DC 20555-000 1 Yankee Atomic Electric Company Yankee Nuclear Power Station Independent Spent Fuel Storage Installation NRC License Nos. DPR-3 and SFGL-13 (NRC Docket Nos.50-029 and 72-31)

Subject:

Request for Exemption from Certain Requirements of 10 CFR 72.2 12 and 10 CFR 72.214 for the Yankee Nuclear Power Station Independent Spent Fuel Storage Installation Pursuant to 10 CFR 72.7, "Specific Exemptions," Yankee Atomic Electric Company (YAEC) requests an exemption from certain requirements of 10 CFR 72.2 12(a)(2), 10 CFR 72.2 12(b)(3),

10 CFR 72.212(b)(5)(i), 10 CFR 72.212(b)(7), 10 CFR 72.212(b)(1 1), and 10 CFR 72.214 for the Yankee Nuclear Power Station (YNPS) Independent Spent Fuel Storage Installation (ISFSI).

Specifically, YAEC is requesting an exemption regarding the method of compliance defined in Amendment 5 of the NAC-MPC Certificate of Compliance (CoC) No. 72-1025, Appendix A, "Technical Specifications for the NAC-MPC System," Technical Specification (TS) A 5.3, "Surveillance After an Off-Normal, Accident, or Natural Phenomena Event." The exemption request is provided in Attachment 1.

The exemption request has been discussed with NAC, the Certificate of Compliance Holder for the NAC-IMPC System, and a copy of the exemption request will be provided to them as part of the distribution of this letter.

As discussed in a teleconference with the NRC on August 13, 2015, YAEC requests approval of this exemption request by December 31, 2015. This requested date would permit YAEC to utilize the Surveillance Requirement, Conditions, Required Actions and associated Completion Times of NAC-MPC TS A 3.1.6 to comply with the requirement of NAC-MPC TS A 5.3 during the upcoming winter and future winters.

Yankee Atomic Electric Company BYR 2015-028/ September 1, 2015/Page 2 The regulatory commitment made in Attachment 1 of this document is defined below.

If you have any questions regarding this submittal, please do not hesitate to contact me at (413) 424-5261 extension 303.

Respectfully, Brian Smith ISF SI Manager Commitment:

1. Following the granting of the exemption, YAEC will continue to proactively manage snow to prevent conditions that could result in inoperability of the Concrete Cask Heat Removal Systems for the NAC-MPC Systems.

Attachment:

1. YAEC Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 cc: D. H. Dorman, NRC Region I Administrator M. S. Ferdas, Chief, Decommissioning Branch, NRC, Region I J. Goshen, NRC Project Manager J. Giarrusso, Planning, Preparedness & Nuclear Section Chief, MVEMA J. Cope-Flanagan, Assistant General Counsel, MIDPU J. Reyes, State of Massachusetts Office of the Attorney General W. Fowler, NAC E. Shewbridge, NAC G. Carver, NAC

Attachment 1 to BYR 2015-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 1.0 Request for Exemption Pursuant to 10 CFR 72.7, "Specific Exemptions," Yankee Atomic Electric Company (YAEC) requests an exemption from certain requirements of 10 CFR 72.2 12(a)(2), 10 CFR 72.2 12(b)(3),

10 CFR 72.212(b)(5)(i), 10 CFR 72.212(b)(7), 10 CFR 72.212(b)(1 1), and 10 CFR 72.214 for the Yankee Nuclear Power Station (YNPS) Independent Spent Fuel Storage Installation (ISFSI).

Specifically, YAEC is requestingan exemption regarding the method of compliance defined in Amendment 5 of the NAC-MPC Certificate of Compliance (CoC) No. 72-1025, Appendix A, "Technical Specifications for the NAC-MPC System," Technical Specification (TS) A 5.3, "Surveillance After an Off-Normal, Accident, or Natural Phenomena Event."

Amendment 5 of the NAC-MPC CoC No. 72-1025, Appendix A, NAC-MIPC TS A 5.3 states:

"A Response Surveillance is required following off-normal, accident or natural phenomena events. The NAC-MPC SYSTEMs in use at an ISFSI shall be inspected within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after the occurrence of an off-normal, accident or natural phenomena event in the area of the ISFSI. This inspection must specifically verify that all the CONCRETE CASK inlets and outlets are not blocked or obstructed. At least one-half of the inlets and outlets on each CONCRETE CASK must be cleared of blockage or debris within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore air circulation."

Specifically, YAEC is requesting the ability to utilize the Surveillance Requirement, Conditions, Required Actions, and Completion Times defined in NAC-MPC TS A 3.1.6 to comply with NAC-MPC TS A 5.3. If granted, YAEC would implement NAC-MPC TS A 5.3 as follows:

"A Response Surveillance [SR 3.1.6.1] is required following off-normal, accident or natural phenomena events. The NAC-MPC SYSTEMs in use at an ISFSI shall be inspected [in accordance with SR 3.1.6.1] within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after the occurrence of an off-normal, accident or natural phenomena event in the area of the ISFSI [to confirm operability of the CONCRETE CASK Heat Removal System for each NAC-MPC System]. This-in~p~ectien clere

.. , f blockage or..debis.. withi 21- hou4rs to..retore ai circulation...

.:- [If a CONCRETE CASK Heat Removal System(s) for one or more NAC-MPC Systems is determined to be inoperable, Condition A of TS A 3.1.6 shall be entered and the Required Action and associated Completion Time met.]"

2.0 Background 10 CFR 72.2 10 issues a general license to store spent fuel in an ISFSI at reactor sites as long as the 10 CFR 50 reactor license remains in effect. 10 CFR 72.212(a)(2) limits the storage of spent fuel to casks approved in 10 CFR 72, Subpart K. 10 CFR 72.2 12(b)(1 1) states that the casks "are approved for storage under the conditions specified in their Certificates of Compliance."

Page 1 of 12

Attachment 1 to BYR 2015-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.2 14 The Nuclear Regulatory Commission (NRC) approved the use of the NAG-Multi-Purpose Canister (MPG) System by issuing Certificate of Compliance (CoG) No. 1025, NRC Docket No. 72-1025), effective April 10, 2000. This constituted NRC approval and the conditions for use in storing spent fuel under the general licensing provisions of 10 CFR 72.2 10.

YAEC is a 10 CFR 72 general licensee that utilizes the NAC-MvPC System in accordance with the requirements of the NAG-MPG System CoG No. 1025. In July, 2011, YAEC notified the NRC that the 15 NAG-MPG canisters storing spent nuclear fuel at the YAEC ISFSI would be registered to Amendment No. 5 of NAG-MPG CoG No. 1025.

The regulations require YAEG to comply with the terms and conditions of the NAG-MPG CoG No. 1025. NAG-MPG CoG No. 1025, Amendment 5 requires the general licensee to meet the requirements of the Technical Specifications (TS) for the NAG-MPG System (Appendix A to the CoG). Thus, the regulations require YAEG to comply with the TS for the NAG-MPG System.

The NAG-MPG TS Limiting Condition for Operation (LCO) 3.1.6, "Concrete Cask Heat Removal System," requires the Concrete Cask Heat Removal System for each NAG-MPG System to be operable. The applicability of this TS is during storage operations. Storage operations is defined in TS A 1.1 to include all activities that are performed at the ISFSI, while an NAG-MPG System containing spent fuel is located on the storage pad within the ISFSI perimeter. For the YNPS ISFSI, this equates to an applicability of"At all times," because there are 15 NAG-MPG Systems that are utilized to store spent fuel on the JSFSI storage pad.

Operability of the Concrete Cask Heat Removal System for each NAG-MPG System is established by performing Surveillance Requirement (SR) 3.1.6.1 at the required frequency.

SR 3.1.6.1 provides the option to establish operability of the Goncrete Gask Heat Removal System for each NAG-MPG System by either verifying that the temperature differential meets the acceptance criteria via temperature monitoring or performing visual verifications of the inlet and outlet screens to ensure that they are not obstructed as defined in the TS Bases. This is consistent with the definition of operability provided in NAG-MPG TS A 1.1.

If SR 3.1.6.1 is not met for a Concrete Cask Heat Removal System for one or more of the NAG-MPG Systems, Condition A of TS A 3.1.6 is entered. Required Action A.1 requires the Concrete Cask Heat Removal System for the affected NAG-MPG System to be restored to an operable status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, otherwise Condition B of TS A 3.1.6 is required to be entered.

In addition TS A 5.3, "Surveillance After an Off-Normal, Accident, or Natural Phenomena Event," provides additional requirements regarding the Concrete Cask Heat Removal System for each NAG-MPG System. TS A 5.3. It requires in part:

"A Response Surveillance is required following off-normal, accident or natural phenomena events. The NAG-MPG SYSTEMs in use at an ISFSI shall be inspected within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after the occurrence of an off-normal, accident or natural phenomena event in the area of the ISFSI. This inspection must specifically verify that all the CONCRETE CASK inlets and outlets are not blocked or obstructed. At least one-half of the inlets and outlets on each Page 2 of 12

Attachment 1 to BYR 2015-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.2 12 and 10 CFR 72.2 14 CONCRETE CASK must be cleared of blockage or debris within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore air circulation."

The requirements of NAC-MIPC TS A 5.3 are not consistent with the requirements of NAC-MPC TS A 3.1.6. These differences include:

NAC-MPC TS A 5.3 is only applicable after the occurrence of an off-normal, accident or natural phenomena event. While NAC-MPC TS A 3.1.6 is applicable during storage operations (i.e., at all times including during the occurrence of off-normal, accident, and natural phenomena events). This inconsistency results in unnecessary complications (including, the potential for different methods of implementation of the requirements) regarding the literal compliance with these TSs.

• TS A 5.3 requires the performance of a response surveillance following off-normal, accident or natural phenomena events in the area of the ISFSI by performing an inspection of the affected NAC-MPC System within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after the occurrence of the event. This inspection is required to specifically verify that all the Concrete Cask inlets and outlets are not blocked or obstructed.

o Literal compliance with TS A 5.3 would not permit the temperature monitoring system to be utilized to determine if there is blockage, because this is a monitoring activity not an inspection activity.

oIn addition, the phrase "after the occurrence" is not defined. For events that occur at a precise period of tirme, e.g., Foss of instrumentation, an earthquake or tornado, it is readily apparent when "after the occurrence" occurs. In the case of an event that leads to blockage of greater than one-half of the inlets or outlets (snow storm), "after the occurrence" is subjective.

TS A 3.1.6 permits the use of temperature monitoring or visual verification in accordance with SR 3.1.6.1 to establish that the Concrete Cask Heat Removal System for each NAC-MPC System is operable. The frequency for conducting the surveillance is at least once every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This surveillance requirement has to be met when TS A 3.1.6 is applicable, i.e., during storage operations.

• TS A 5.3 permits 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to clear the blockage or debris from at least one-half of the inlets and outlets on each affected Concrete Cask (NAC-MPC System).

In the event visual verification of the inlets and outlets screens are utilized to meet SR 3.1.6.1 to establish operability and the air inlet or outlet screens are determined to be obstructed as defined in the Bases for SR 3.1.6.1 in Appendix 12C of the NAC-MPC Final Safety Analysis Report (FSAR), then the affected Concrete Cask Heat Removal System(s) is required to be declared inoperable. Condition A of TS A 3.1.6 would be entered. TS A 3.1.6, Required Action A. 1 requires the Concrete Cask Heat Removal System for each affected NAC-MIPC System to be restored to an operable status within 8 Page 3 of 12

Attachment 1 to BYR 2015-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 hours. If the Required Action is not met within the associated Completion Time, Condition B of TS A 3.1.6 is required to be entered.

3.0 Technical Justification The purpose of both NAC-MPC TS A 3.1.6 and NAC-MiPC TS A 5.3 is to ensure that the Concrete Cask Heat Removal System for each NAC-MPC System in use remains operable.

However, the methodology defined in the two TSs are inconsistent. YAEC is requesting the ability to utilize the Surveillance Requirement, Conditions, Required Actions, and Completion Times defined in NAC-MPC TS A 3.1.6 to comply with NAC-MPC TS A 5.3. If granted, YAEC would implement NAC-MPC TS A 5.3 as follows:

"A Response Surveillance [SR 3.1.6.1] is required following off-normal, accident or natural phenomena events. The NAC-MPC SYSTEMs in use at an ISFSI shall be inspected [in accordance with SR 3.1.6.1] within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after the occurrence of an off-normal, accident or natural phenomena event in the area of the ISFSI [to confirm operability of the CONCRETE CASK Heat Removal System for each NAC-MPC System]. 4Thipee .... *:r must specifically veri*' that all the CONCP*TE CASK inlets and outlets are not blocked or obtrctd.t f lat one half.o

• the: inet and cutl. t on eac [IfTCSKmstb leared of bockage or debris.with.n.2..h.ur..t. restore air circulation. [fa CONCRETE CASK Heat Removal System(s) for one or more NAC-MIPC Systems is determined to be inoperable, Condition A of TS A 3.1.6 shall be entered and the Required Action and associated Completion Time met.]"

3.1 Utilization of SR 3.1.6.1 SR 3.1.6.1 permits temperature monitoring or visual inspection of the inlet and outlet screens to be utilized to establish the operability of the Concrete Cask Heat Removal System for each NAC-MIPC System to comply with LCO 3.1.6. The same method should also apply to compliance with the requirement of NAC-MPC TS A 5.3 to perform a response surveillance within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after the occurrence of an off-normal, accident, or natural phenomena.

The Bases for NAC-MPC TS A 3.1.6, SR 3.1.6.1 establishes that either visual inspection of the inlets and outlets screens or temperature monitoring will establish that adequate air flow past the canister is occurring and heat transfer is taking place. It states:

"Visual observation that all four air inlet and outlet screens are unobstructed and intact ensures that air flow past the CANISTER is occurring and heat transfer is taking place.. .Alternatively, based on the thermal analyses, if the air temperature rise is less than the limits stated in the SR, adequate air flow and, therefore, adequate heat transfer is occurring to provide assurance of long-term fuel cladding integrity..." [Note: Each Vertical Concrete Cask has four inlet screens and four outlet screens, i.e., four sets of inlet and outlet screens or a total of eight inlet and outlet screens.]

This is consistent with the definition of operability provided in NAC-MPC TS A 1.1:

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Attachment 1 to BYR 2015-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 "An OPERABLE CONCRETE CASK heat removal system transfers sufficient heat away from the fuel assemblies such that the fuel cladding, CANISTER component and CONCRETE CASK temperatures do not exceed applicable limits. The CONCRETE CASK heat removal system is considered OPERABLE if the difference between the 1SF SI ambient temperature and the average outlet air temperature is < 92 0 F for the YANKEE-MPC . . .or if all four air inlet and outlet screens are visually verified to be unobstructed..." [Note: Each Vertical Concrete Cask has four inlet screens and four outlet screens, i.e., four sets of inlet and outlet screens or a total of eight inlet and outlet screens.]

The following statements from the NAC-MIPC Final Safety Analysis Report (FSAR) support the use of either method defined in SR 3.1.6.1 to establish operability to comply with NAC-MPC TS A 3.1.6 or NAC-MPC TS A 5.3:

Section FSAR Statement 11.1.1.1 This event [Blockage of Half of the Air Inlets] would be detected by the daily concrete cask operability inspection, which is performed either by outlet air temperature measurements or by visual inspection of the inlet and outlet screens for blockage and integrity...

11.1.3.2 For concrete casks incorporating daily temperature-monitoring programs, the maximum time period during which an increase in outlet air temperatures may go undetected is 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The principal condition that could cause an increase in temperature is the blockage of the air inlets and/or outlets. Section 11.2.8 shows that even if all of the inlets and outlets of a single cask are blocked immediately after a temperature measurement, it would take longer than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> before any component approaches its allowable temperature limit. Therefore, there would be sufficient time to identify and correct temperature instrumentation failure events prior to critical system components reaching their temperature

__________________ limits.

11. 1.3.5 Following the loss of instrumentation, the temperature instrumentation shall be replaced or repaired and returned to service to allow the surveillance requirements and frequency of LCO 3.1.6 to be met.

Alternatively, the surveillance requirement may be met by the daily visual inspection of the inlet and outlet screens of each concrete cask to verify they are not blocked and are intact.

11.2.2.5 Response Surveillance of the storage casks at the ISFSI is required following an earthquake accident in accordance with Section A 5.3 of the Technical Specifications to verify the heat removal systems of the casks are operable.

11.2.3.5 Response Surveillance of the storage casks at the ISFSI in accordance with Section A 5.3 of the Technical Specifications is required following an explosion event to verify the heat removal systems of the casks are

______________operable.

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Attachment 1 to BYR 20 15-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 Section FSAR Statement 11.2.6.5 Response Surveillance of the NAG-MPG systems at the ISFSI shall be performed following the flood accident in accordance with Section A 5.3 of the Technical Specifications to verify the heat removal systems of the

______________casks are operable.

TS A 5.3 wasrevised in Amendment 5 to NAG-MPG CoC No. 1025 that was issued by the NRC on July 24, 2007. Prior to Amendment 5, TS A 5.3 was met by performance of SR 3.1.6.2.

SR 3.1.6.2 required the verification of the temperature difference between the average Concrete Cask air outlet temperature and the ISFSI ambient temperature meets the acceptance criterion within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after an off-normal, accident, or natural phenomena. This TS did not allow for visual verification at this time. However, SR 3.1.6.2 was eliminated in Amendment 5 to NAG-MPG CoC No. 1025, and TS A 5.3 was rewritten.

The NRC's Safety Evaluation Report (SER) for Amendment 5 to NAG-MPG CoG No. 1025 dated July 24, 2007, includes statements that make it clear that the applicable TS revisions were intended to permit the use of visual verifications of the outlets and inlets or temperature monitoring in accordance with SR 3.1.6.1 to ensure the operability of the Concrete Cask Heat Removal System for each NAG-MPG System.

Section Statement Thermal The application proposed several modifications to the TS and the FSAR Evaluation to include the option to visually verify that all four air inlet and outlet screens are unobstructed and operable in lieu of daily temperature monitoring.

Thermal Chapter 2.0, Principle Design Criteria, was revised throughout to reflect Evaluation the alternative for daily visual inspection of the air inlet and outlet screen for blockage Thermal Chapter 10.0, Radiation Protection, of the FSAR was revised to add an Evaluation option for temperature measurement or daily visual monitoring of cask inlet and outlet screens for the purpose of verifying that they are unobstructed.

Thermal Chapter 11.0, Accident Analysis, was revised throughout to include Evaluation changes associated with the revised thermal monitoring requirement allowing visual inspections of air inlet and outlet screens. The changes refer to the basis of the analysis for verifying the safety of the cask for blockages of 24-hours or less.

In addition, this is consistent with Amendment 4 of NAC-MPC CoG No. 1025, which is currently effective for those sites that invoke Amendment 4. It still allows the use of temperature monitoring as the way to demonstrate operability of the Concrete Cask Heat Removal System for each NAG-MPG System by performing the surveillance invoked by TS A 5.3 (i.e., SR 3.1.6.2).

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Attachment 1 to BYR 20 15-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 3.2 Utilization of Conditions, Required Actions, and Completion Times of TS A 3.1.6 TS A 5.3 permits 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to clear the blockage or debris from at least one-half of the inlets and outlets on each Concrete Cask. This requirement causes confusion (including the potential for different implementation of the requirements), because it is different than Required Action A. 1 of TS A 3.1.6 and its associated Completion Time which require the Concrete Cask Heat Removal System for the affected NAC-MIPC System to be restored to an operable status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

The 24-hour time frame identified in TS A 5.3 may only be utilized if the operability of the Concrete Cask Heat Removal Systems for the NAC-MPC Systems is established by utilizing the temperature monitoring system as defined in SR 3.1.6.1. If YAIEC is relying on visual verification of the inlet and outlet screens to establish operability of the Concrete Cask Heat Removal System for each NAC-MPC System in accordance with SR 3.1.6.1, and the SR is not met, then Condition A of TS A 3.1.6 would be entered and the Concrete Cask Heat Removal System for the affected NAC-MPC System must be restored to an operable status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

3.3 Other Considerations Section 11.1.1 of the NAC-MPC FSAR provides an evaluation of the NAC-MPC storage cask for the steady state effects of a blockage of one-half of the air inlets at the normal ambient temperature (75°F). Section 11.1.2 of the NAC-MPC FSAR concludes that the component temperatures are within the allowable temperature range with one-half of the inlets blocked.

Currently, YAEC actively manages the accumulation of snow on the 1SF SI pad to ensure that the inlet screens for the concrete casks are not blocked to prevent the occurrence of an off-normal event and entry into TS A 5.3. Blockage of the outlet screens by snow would be unusual.

Following the granting of the requested exemption, YAEC will continue to ensure that the Concrete Cask Heat Removal System for each NAC-MPC System remains operable by complying with the requirements of TS A 3.1.6. YAEC can more accurately comply with operability assessments "after the occurrence" of the event using temperature monitoring than the more subjective visual verification.

Chapter 11 of the NAC-MIPC FSAR includes analysis for off-normal events, accidents, and natural phenomenon events. The natural phenomenon events analyzed in Chapter 11 of the NAC-MPC are severe environmental conditions (Section 11.1.4), earthquake (Section 11.2.2),

flood (Section 11.2.6), lightning strike (Section 11.2.9), exceedance of maximum anticipated heat load (Section 11.2.10), and tornado and tornado driven missiles (Section 11.2.13). In addition, while a snow storm is not specifically analyzed as a natural phenomenon event in Section 11 of the NAC-MPC FSAR, it can lead to an off-normal event involving blockage of greater than one-half of the inlet screens, as defined in Section 11.1.1 of the NAC-MPC FSAR.

A snow storm can result in accumulation in front of and even into the inlet vents, and can have the appearance of "blockage," when using an inspection process. However, based on experience, YAEC does not expect blockage due to snow to affect the operability of the Concrete Cask Heat Removal System for a NAC-MPC System, because the differential temperature remains well Page 7 of 12

Attachment 1 to BYR 2015-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.2 12 and 10 CFR 72.2 14 below the limit defined in TS SR 3.1.6.1. YAEC clears snow proactively to preclude: 1) entry into TS A 5.3; and 2) gradual ice formation by freeze-thaw cycles acting on snow accumulation that could obstruct the inlets and outlets screens such that operability of the Concrete Cask Heat Removal System for a NAC-MPC System may be challenged.

Following the granting of the exemption, YAEC will continue to proactively manage snow to prevent conditions that could result in inoperability of the Concrete Cask Heat Removal Systems for the NAC-MPC Systems. The exemption will permit YAEC the flexibility to adapt its snow management methodology to respond to actual conditions affecting the Concrete Cask Heat Removal Systems and not specifically in response to subjective criteria with indeterminate starting times.

4.0 Applicable Regulations The specific requirements for granting exemptions to 10 CFR Part 72 licensing requirements are set forth in 10 CFR 72.7, "Specific exemptions," which states:

"The Commission may, upon application by any interested person or upon its own initiative, grant such exemptions from the requirements of the regulations in this part as it determines are authorized by law and will not endanger life or property or the common defense and security and are otherwise in the public interest."

5.0 Exemption Request Considerations YAEC has reviewed 10 CFR 72 and determined that an exemption to certain requirements of 10 CFR 72.212(a)(2), 10 CFR 72.212(b)(3), 10 CFR 72.212(b)(5)(i), 10 CFR 72.212(b)(7),

10 CFR 72.212(b)(1 1), and 10 CFR 72.214 are necessary to permit the YNPS ISFSJ to utilize the Surveillance Requirement, Conditions, Required Actions, and Completion Times defined in NAC-MPC TS A 3.1.6 to comply with the requirement of NAC-MPC TS A 5.3.

5.1 Authorized by Law 10 CFR 72.7 allows the NRC to grant exemptions from the requirements of 10 CFR 72. Granting ofthe proposed exemptions will not result in a violation of the Atomic Energy Act of 1954, as amended, or the Commission's regulations. Therefore, the exemptions would be authorized by law.

5.2 No Undue Risk to Public Health and Safety Chapter 11 of the NAC-MPC FSAR provides analyses of loss of instrumentation, blockage of half of the air inlets, full blockage of air inlets and outlets, and various natural phenomena events. No new accident precursors are created by utilizing the Surveillance Requirement, Conditions, Required Actions, and Completion Times defined in NAC-MPC TS A 3.1.6 to comply with NAC-MIPC TS A 5.3. Thus, the probability of postulated accidents is not increased.

Also, based on the above, the consequences of postulated accidents are not increased. No Page 8 of 12

Attachment 1 to BYR 2015-028 YAEC Request for Exemption from Certain Requirements of 10 CER 72.212 and 10 CFR 72.214 changes are being made in the types or amounts of effluents that may be released offsite. There is no significant increase in occupational or public radiation exposure. Therefore, there is no undue risk to public health and safety.

5.3 Consistent with the Common Defense and Security The YNPS ISFSI will continue to be managed in accordance with the YNPS ISFSI Physical Security Plan, and the outstanding NRC Orders and Interim Compensatory Measures. The proposed exemption will not alter the scope of the licensee's security program. Therefore, the common defense and security is not impacted by this exemption.

5.4 Special Circumstances While 10 CFR 72.7 does not specify a presentation of "special circumstances" similar to those required for 10 CFR 50 exemptions, YAEC's exemption request can be elucidated by using three of the special circumstances identified in 10 CFR 50.12. The applicable special circumstances are discussed below:

5.4.1 10 CFR 50.12(a)(2)(i) - Application of the regulation in the particular circumstances conflicts with other rules or requirements of the Commission YAEC must comply with the terms and conditions of the NAC-MIPC CoC No. 1025, including the TS. NAC-MPC TS A 1.1, Definition of Operability and NAC-MPC TS SR 3.1.6.1 both defines that the Concrete Cask Heat Removal System for each NAC-MPC System can be determined to be operable by utilizing temperature monitoring or visual verifications of the inlet and outlet screens. However, literal compliance with NAC-MPC TS A 5.3 only permits inspections of the inlet and outlet vents to be performed to verify' operability. In addition, the time frame permitted by TS A 5.3 for clearing of blockage or obstructions is not consistent with the requirements of TS A 3.1.6. Permitting the Surveillance Requirement, Conditions, Required Actions, and associated Completion Times of NAC-MPC TS A 3.1.6 to comply with NAC-MIPC TS A 5.3 would resolve these inconsistencies.

5.4.2 10 CFR 50.12(a)(2)(ii) - Application of the regulation in the particular circumstances would not serve the underlying purpose of the rule or is not necessary to achieve the underlying purpose.

The underlying purpose of 10 CFR 72.2 12 is to allow reactor licensees to utilize dry fuel storage casks that have previously been found to be safe and appropriately analyzed for use by the cask designer, the cask user, and the NRC. The intent of NAC-MIPC TS A 3.1.6 and A 5.3 is to ensure that the Concrete Cask Heat Removal System for each NAC-MPC System remains operable.

The definition of operability provided in NAC-MPC TS A 1.1 defines that the Concrete Cask Heat Removal System for each NAC-MPC System is considered operable if the difference between the ISFSI ambient temperature and the average outlet air temperature is < 92°F for the YANKEE-MPC System or if all air inlet and outlet screens are visually verified to be unobstructed. The Bases for NAC-MPC TS A 3.1.6, SR 3.1.6.1 establishes that either visual Page 9 of 12

Attachment 1 to BYR 2015-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.2 14 inspection of the inlets and outlets screens or temperature monitoring will establish that adequate air flow past the canister is occurring and heat transfer is taking place.

5.4.3 10 CFR 50.12(a)(2)(iii) - Compliance would result in undue hardship or other costs that are significantly in excess of those contemplated when the regulation was adopted, or those incurred by others similarly situated.

Currently, YAEC proactively engages in the removal of snow that could block the inlet screens for the NAC-MPC Systems t~o avoid having the effective area of the inlet screens for any single NAC-MPC System to be blocked by greater than 50% and preclude ice formations that could block the inlet screens. Note: Snow blockage of the outlet screens would be unusual. As a result, YAEC often puts individuals in harm's way during blizzards and slippery winter conditions to ensure compliance with NAC-MPC TS A 5.3 due to the inability to utilize the temperature monitoring system to comply with NAC-MPC TS A 5.3. Additionally, verification that the inlet and outlet screens are free of blockage during a snowstorm is a difficult and subjective process which does not provide the level of demonstrated, documented acceptability that the temperature differential readings provide. This fact and operational flexibility is the reason that YAEC installed and maintains a temperature monitoring system. The exemption would give YAEC the operational flexibility during dynamic environmental conditions.

The additional operational flexibility would allow YAEC to maintain doses to workers As Low As Reasonably Achievable (ALARA), because the frequency for clearing the vents would be reduced, and the clearing of the vents would be conducted in weather conditions that would improve efficiency.

6.0 Environmental Consideration The proposed exemption does not increase the probability or consequences of accidents, no changes would be made to the types of effluents released offsite, and there would be no increase in occupational or public radiation exposure. Therefore, there are no significant radiological environmental impacts associated with the proposed action. Additionally the proposed action would not involve any construction or other ground disturbing activities, would not change the footprint of the existing ISESI, and would have no other significant non-radiological impacts.

The ISFSI is located on previously disturbed land, thus, the proposed exemption does not have the potential to create any significant impact on aquatic or terrestrial habitat in the vicinity of the ISFSI, or to threatened, endangered, or protected species. In addition, the proposed exemption does not have the potential to cause effects on historic or cultural properties, assuming such properties are present at the site of the YNPS ISFSI.

The proposed exemption would meet the eligibility criterion for categorical exclusion set forth in 10 CFR 51 .22(c)(25), because the proposed exemption involves: (i) no significant hazards consideration; (ii) no significant change in the types or significant increase in the amounts of any effluents that may be released offsite; (iii) no significant increase in individual or cumulative public or occupational radiation exposure; (iv) no significant construction impact; (v) no significant increase in the potential for or consequences from radiological accidents; and (vi) the Page 10 of 12

Attachment 1 to BYR 2015-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 requirements from which the exemption is sought involve inspection or surveillance requirements. Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed exemption.

7.0 Conclusion YAEC has reviewed 10 CFR 72 and determined that an exemption to certain requirements of 10 CFR 72.212(a)(2), 10 CFR 72.212(b)(3), 10 CFR 72.212(b)(5)(i), 10 CFR 72.212(b)(7),

10 CFR 72.212(b)(1 1), and 10 CFR 72.214 is necessary to permit the YNPS JSFSI to effectively utilize the Surveillance Requirement, Conditions, Required Actions and associated Completion Times of NAC-MPC TS A 3.1.6 to comply with the requirement of NAC-MPC TS A 5.3.

Such an exemption meets the specific exemption requirements of 10 CFR 72.7. The requested exemption is authorized by law, will not endanger life or property, and is consistent with the common defense and security. Special circumstances as defined in 10 CFR 50.12(a)(2)(i),

10 CFR 50.12(a)(2)(ii) and (iii) would be present. In addition, the exemption request would meet the eligibility criterion for categorical exclusion set forth in 10 CFR 51 .22(c)(25).

YAEC requests approval of this exemption request by December 31, 2015. This requested date would permit YAEC to utilize the Surveillance Requirement, Conditions, Required Actions and associated Completion Times of NAC-MPC TS A 3.1.6 to comply with the requirement of NAC-MPC TS A 5.3 during the upcoming winter and future winters.

8.0 Precedent No previous examples of an NRC-approved exemption request that dealt with a similar issue could be found. However, on July 15, 2010 (Reference 7), the NRC granted YAEC an exemption from certain sections of 10 CFR 72.212 and 10 CFR 72.214 regarding the NAC-MPC CoC and its Technical Specifications that establish that this type of exemption request is not a novel approach.

In addition, the Technical Specifications for the following 10 CFR 72 approved storage systems rely on the Technical Specifications for the Concrete Cask Heat Removal System to maintain operability during and following an off-normal, accident, or natural phenomenon event, because they do not possess a Technical Specification similar to NAC-MPC TS A 5.3:

1. Appendix A of Certificate of Compliance No. 1031, Technical Specifications and Design Features for the Magnastor System, Amendment No. 4.

2. Appendix A of Certificate of Compliance No. 1040, Technical Specifications for the Hi-Storm UMAX Canister Storage System, Amendment No. 0.

3. Appendix A of Certificate of Compliance No. 1014, Technical Specifications for the Hi-Storm 100 Cask System, Amendment No. 8.

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Attachment 1 to BYR 2015-028 YAEC Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214

4. Appendix A of Certificate of Compliance No. 1032, Technical Specifications for the Hi-Storm FW MPC Storage System, Amendment No. 1.

9.0 References

1. Certificate of Compliance (CoG) for the NAC International (NAC) Multi-Purpose Canister (MiPC) System, U.S. Nuclear Regulatory Commission, April 10, 2000.

2. Amendment 5 of NAC-MPC Certificate of Compliance No. 1025, including Appendix A, "Technical Specifications for the NAC-MPC System."

3. Amendment 4 of NAC-MPC Certificate of Compliance No. 1025, including Appendix A, "Technical Specifications for the NAC-MPC System."

4. NAC-MPC FSAR, Chapter 11, "Accident Analysis," and Appendix 12C, "Technical Specification Bases for the NAC-MPC System."

5. Letter from R. Mitchell (YAEC) Document Control Desk (NRC), "Yankee Atomic Electric Company Adoption of NAC-MIPC System, Amendment 5 Certificate of Compliance and Cask Registration," BYR 2011-018, July 28, 2011.

6. NRC Safety Evaluation Report, Docket No. 72-1025, NAC-MPC Storage System, Certificate of Compliance No. 1025, Amendment No. 5, dated July 24, 2007.

7. Letter from J. Goshen (NRC) to R. Mitchell (YAEC), Exemption from 10 CFR 72.2 12 and 72.214 for Dry Spent Fuel Storage Activities - Yankee Atomic Independent Spent Fuel Storage Installation (TAC No. L24421), dated July 15, 2010.

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