ML24046A258
| ML24046A258 | |
| Person / Time | |
|---|---|
| Site: | Holtec |
| Issue date: | 02/15/2024 |
| From: | Holtec |
| To: | Office of Nuclear Material Safety and Safeguards |
| Shared Package | |
| ML24046A254 | List: |
| References | |
| 5014978 | |
| Download: ML24046A258 (1) | |
Text
SFSC Heat Removal System 3.1.2 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY
SR 3.1.2 Verify all OVERPACK inlets and outlets are free Table 3-5 of blockage from solid debris or floodwater.
OR For OVERPACKS with installed temperature Table 3-5 monitoring equipment, verify that the difference between the average OVERPACK air outlet temperature and ISFSI ambient temperature is
< 155oF for OVERPACKS containing PWR MPCs, < 137oF for OVERPACKS containing BWR MPCs (except MPC-68M) and 164°F for OVERPACKS containing MPC-68M. For sites that have loaded in accordance with the Topical Report HI-2200343-A , verify that the difference between the average OVERPACK air outlet temperature and ISFSI ambient temperature is less than or equal to the value computed using the topical report methodology for T.
Certificate of Compliance No. 1014 Amendment No. 18 Appendix A 3.1.2-2 MPC Helium Backfill Limits Table 3-2
- 8. Vacuum drying of the MPC must be performed using cycles of the drying system, according to the guidance contained in ISG-11 Revision 3. The time limit for these cycles shall be determined based on site specific conditions. Applies when any one assembly heat load is greater than 0.426 kW.
- 9. Alternative heat load limits may be developed following the methodology in Topical Report HI-2200343-A. These patterns must have a total MPC heat load less than or equal to 50 kW. Dryness criteria are still as specified in Notes 1 or 2 as applicable to the selected drying process, and Note 3 still applies to vacuum drying.
Certificate of Compliance No. 1014 Amendment No. 18 Appendix A 3.3.1-4 MPC Helium Backfill Limits Table 3-2
or OR regionalized loading per Table 3-3 29.3 psig and 48.5 psig
ii. Cask Heat Load > 28.19 kW -
uniformly distributed 45.5 psig and 48.5 psig or greater than regionalized heat load limits per Table 3-3
iii. Cask Heat Load 42.8 kW QSHL Loading Pattern shown in 43.5 psig and 46.5 psig Appendix B, Figure 2.4 -1 QSHL patterns shown in Appendix B, 45.5 psig and 48.5 psig Figures 2.4- 2 through2.4-4
Notes
- 1. Helium used for backfill of MPC shall have a purity of 99.995%. Pressure range is at a reference temperature of 70 oF
- 2. For heat load patterns developed in accordance with Table 3-1a , Note 9, helium backfill limits shall be calculated in accordance with Topical Report HI-2200343-A
Certificate of Compliance No. 1014 Amendment No. 18 Appendix A 3.3.1-7 LCO Completion Time Table 3-5 Table 3-5: Completion Time for Actions to Restore SFSC Heat Removal System OperableNote 2
MPC Material MPC Type Decay Heat Limits per Condition B Condition C Surveillance Storage Location Completion Time Completion Time Frequency
MPC-24/24E/24EF
Alloy X Except MPC-32/32F Appendix B, Section 2.4 Duplex1 8 hrs 24 hrs 24 hrs MPC-68/68F/68FF/68M
MPC-68M Appendix B, Figures 2.4-1 through 2.4-4
MPC-24/24E/24EF
Alloy X MPC-32/32F Appendix B, Section 2.4 8 hrs 16 hrs 16 hrs
MPC-68/68F/68FF/68M
Alloy X MPC-68M Appendix B, Figures 4 hrs 12 hrs 12 hrs 2.4-1 through 2.4-4 MPC-24 Appendix A, Table 3-3 (Regionalized)
MPC-24E/EF Alloy X Except OR 8 hrs 64 hrs 24 hrs Duplex1 MPC-32/32F Appendix A, Table 3-4 MPC-68/68F/68FF/68M (Uniform)
MPC-24 Appendix A, Table 3-3 (Regionalized)
MPC-24E/EF Alloy X OR 8 hrs 24 hrs 24 hrs MPC-32/32F Appendix A, Table 3-4 MPC-68/68F/68FF/68M (Uniform)
MPC-24/24E/24EF 0.75 kW
Alloy X MPC-32/32F 0.5 kW 24 hrs 64 hrs 30 days
MPC-68/68F/68FF/68M 0.264 kW
Note
- 1) If any component of the MPC is made of duplex, these completion times are not applicable.
- 2) For patterns developed in accordance with Table 3-1a , Note 9, alternative completion times shall be calculated in accordance with Topical Report HI-2200343-A
Certificate of Compliance No. 1014 Amendment No. 18 Appendix A 3.3.1-10 Approved Contents 2.0 2.4.2 Regionalized Fuel Loading Decay Heat Limits for ZR -Clad Fuel for VENTILATED OVERPACK
The maximum allowable decay heat per fuel storage location for intact or undamaged fuel assemblies in regionalized loading is determined using the following equations:
Q(X) = 2 x Q0 / (1 + Xy) y = 0.23 / X0.1 q2 = Q(X) / (n1 x X +n2) q1 = q2 x X
Where:
Q0 = Maximum uniform storage MPC decay heat (34 kW)
X = Inner region to outer region assembly decay heat ratio (0.5 X 3) n1 = Number of storage locations in inner region from Table 2.4- 2.
n2 = Number of storage locations in outer region from Table 2.4- 2.
Allowable heat loads for Damaged Fuel and Fuel Debris in regionalized loading are shown in Table 2.4- 5.
Optional loading patterns for MPC-68M are shown in Figures 2.4-1 through 2.4-4.
Alternatively to the heat load patterns in Sections 2.4.1 and 2.4.2, per cell allowable heat loads may be determined per Topical Report HI-2200343-A.
Certificate of Compliance No. 1014 Amendment No. 18 Appendix B 2-51 Approved Contents 2.0 2.4.3 Burnup Limits as a Function of Cooling Time for ZR -Clad Fuel for VENTILATED OVERPACK
The maximum allowable ZR -clad fuel assembly average burnup varies with the minimum required fuel assembly cooling time. Tables 2.4- 3 and 2.4- 4 provide for each MPC the allowable maximum burnup based on the assemblys particular cooling time. These same limits apply for heat load patterns developed in accordance with the topical report , HI-2200343-A.
2.4.3.1 Linear interpolation of burnups between cooling times is permitted. For example, the allowable burnup for a cooling time of 4.5 years may be interpolated between those burnups calculated for 4 year and 5 years.
2.4.3.2 Calculated burnup limits shall be rounded down to the nearest integer.
2.4.3.3 Calculated burnup limits greater than 68,200 MWD/MTU for PWR fuel and 65,000 MWD/MTU for BWR must be reduced to be equal to these values .
2.4.4 When complying with the maximum fuel storage location decay heat limits, users must account for the decay heat from both the fuel assembly and any NON-FUEL HARDWARE, as applicable for the particular fuel storage location, to ensure the decay heat emitted by all contents in a storage location does not exceed the limit.
2.4.5 Fuel Loading Decay Heat Limits for UNVENTILATED OVERPACK
Tables 2.4- 6a and 2.4-6b provide the maximum allowable decay heat per fuel storage location for MPC -68M in an UNVENTILATED OVERPACK.
A minor deviation from the prescribed loading pattern in an MPCs permissible contents to allow one slightly thermally -discrepant fuel assembly per quadrant to be loaded as long as the peak cladding temperature for the MPC remains below the ISG -11 Rev 3 requirements is permitted for essential dry storage campaigns to support decommissioning.
Certificate of Compliance No. 1014 Amendment No. 18 Appendix B 2-53