ML20335A084
| ML20335A084 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 11/18/2020 |
| From: | Exelon Generation Co |
| To: | Office of Nuclear Material Safety and Safeguards |
| Shared Package | |
| ML20335A110 | List: |
| References | |
| Download: ML20335A084 (29) | |
Text
CHAPTER 1 INTRODUCTION AND GENERAL DESCRIPTION OF INSTALLATION LIST OF EFFECTIVE PAGES PAGE REVISION PAGE REVISION LEP 1-1 28 l 1-i 26 1-ii 26 1-iii 26 1-iv 26 1.1-1 26 1.1-2 26 1.2-1 26 1.2-2 26 1.2-3 26 1.2-4 26 1.2-5 26 1.2-6 26 1.3-1 26 1.3-2 26 1.3-3 26 1.3-4 26 1.3-5 26 1.3-6 26 1.3-7 26 1.3-8 26 1.3-9 26 1.3-10 26 1.3-11 26 1.3-12 26 1.4-1 22 1.5-1 8 1.5-2 26 1.6-1 26 Figure 1.1-1 3 Figure 1.1-2 27 Figure 1.1-3 (Page 1 of 2) 28 l Figure 1.1.3 (Page 2 of 2) 28 l Figure 1.2-1 26 Figure 1.3-1 0 Figure 1.3-2 26 Figure 1.3-3 26 Figure 1.3-4 26 Figure 1.3-5 26 Figure 1.3-7 26 Figure 1.3-8 26 Figure 1.3-9 26 Figure 1.3-10 26 CALVERT CLIFFS ISFSI USAR LEP 1-1 Rev. 28
CHAPTER 1 INTRODUCTION AND GENERAL DESCRIPTION OF INSTALLATION TABLE OF CONTENTS PAGE
1.0 INTRODUCTION
AND GENERAL DESCRIPTION OF INSTALLATION 1.1-1
1.1 INTRODUCTION
1.1-1 1.2 GENERAL DESCRIPTION OF INSTALLATION 1.2-1 1.2.1 GENERAL DESCRIPTION 1.2-1 1.2.2 PRINCIPAL SITE CHARACTERISTICS 1.2-1 1.2.3 PRINCIPAL DESIGN CRITERIA 1.2-1 1.2.4 OPERATING AND FUEL HANDLING SYSTEMS 1.2-2 1.2.5 SAFETY FEATURES 1.2-2 1.2.6 RADIOACTIVE WASTE AND AUXILIARY SYSTEMS 1.2-2 1.3 GENERAL SYSTEMS DESCRIPTIONS 1.3-1 1.3.1 SYSTEMS DESCRIPTIONS 1.3-1 1.3.1.1 Dry Shielded Canister Design 1.3-1 1.3.1.2 Horizontal Storage Module 1.3-3 1.3.1.3 Transfer Cask 1.3-6 1.3.1.4 Transfer Equipment 1.3-6 1.3.1.5 Transfer Cask Skid and Positioning System 1.3-8 1.3.1.6 Hydraulic Ram System 1.3-8 1.3.1.7 Vacuum Drying System 1.3-9 1.3.1.8 Closure Welding System 1.3.9 1.3.1.9 System Operation 1.3-10 1.4 IDENTIFICATION OF AGENTS AND CONTRACTORS 1.4-1 1.5 MATERIAL INCORPORATED BY REFERENCE 1.5-1
1.6 REFERENCES
1.6-1 CALVERT CLIFFS ISFSI USAR 1-i Rev. 26
CHAPTER 1 INTRODUCTION AND GENERAL DESCRIPTION OF INSTALLATION LIST OF TABLES TABLE PAGE 1.2-1 DESIGN PARAMETERS FOR THE CALVERT CLIFFS ISFSI 1.2-3 USING A NUHOMS-24P OR NUHOMS-32P DSC 1.2-2 PRIMARY DESIGN PARAMETERS FOR THE NUHOMS-24P 1.2-4 or NUHOMS-32P DSC TRANSFER SYSTEM 1.2-3 DESIGN PARAMETERS FOR THE CALVERT CLIFFS ISFSI 1.2-5 USING A NUHOMS-32PHB DSC 1.2-4 PRIMARY DESIGN PARAMETERS FOR THE 1.2-6 NUHOMS-32PHB DSC TRANSFER SYSTEM 1.3-1 MAJOR SYSTEMS, SUBSYSTEMS, AND COMPONENTS OF 1.3-11 THE CALVERT CLIFFS ISFSI FOR A NUHOMS-24P OR NUHOMS-32P DSC 1.3-2 MAJOR SYSTEMS, SUBSYSTEMS, AND COMPONENTS OF 1.3-12 THE CALVERT CLIFFS ISFSI FOR A NUHOMS-32PHB DSC 1.5-1 SECTION REFERENCE FOR NUHOMS TOPICAL REPORTS 1.5-2 CALVERT CLIFFS ISFSI USAR 1-ii Rev. 26
CHAPTER 1 INTRODUCTION AND GENERAL DESCRIPTION OF INSTALLATION LIST OF FIGURES FIGURE 1.1-1 CALVERT CLIFFS SITE PLAN 1.1-2 ISFSI CASK LOADING MAP 1.1-3 ISFSI CASK LOADING DATABASE 1.2-1 GENERAL LOCATION 1.3-1 NUHOMS-24P DRY SHIELDED CANISTER ASSEMBLY COMPONENTS 1.3-2 NUHOMS ON-SITE TRANSFER CASK 1.3-3 NUHOMS TRANSFER TRAILER 1.3-4 NUHOMS CASK SUPPORT SKID 1.3-5 NUHOMS HYDRAULIC RAM SYSTEM 1.3-6 Deleted 1.3-7 NUHOMS-32P DRY SHIELDED CANISTER BASKET ASSEMBLY COMPONENTS 1.3-8 SELF-PROPELLED MODULAR TRANSPORTER WITH RAM AND SKID ASSEMBLY 1.3-9 MODIFIED NUHOMS ON-SITE TRANSFER CASK 1.3-10 HSM-HB SCHEMATIC CALVERT CLIFFS ISFSI USAR 1-iii Rev. 26
CHAPTER 1 INTRODUCTION AND GENERAL DESCRIPTION OF INSTALLATION LIST OF ACRONYMS BGE Baltimore Gas and Electric Company CCNPP Calvert Cliffs Nuclear Power Plant DSC Dry Shielded Canister HSM Horizontal Storage Module HSM-HB High Burnup Horizontal Storage Module ISFSI Independent Spent Fuel Storage Installation NUHOMS Nutech Horizontal Modular Storage SPMT Self-Propelled Modular Transporter TCSS Transfer Cask Support Skid CALVERT CLIFFS ISFSI USAR 1-iv Rev. 26
1.0 INTRODUCTION
AND GENERAL DESCRIPTION OF INSTALLATION
1.1 INTRODUCTION
Baltimore Gas and Electric Company (BGE) began commercial operation of the Calvert Cliffs Nuclear Power Plant (CCNPP), Units 1 and 2 on May 8, 1975 and April 1, 1977, respectively.
Since then, these two 2737 MWT units have generated millions of KWH in a safe and reliable manner. In so doing, these units have discharged spent fuel assemblies. These assemblies are currently stored in a common storage pool. The need to provide additional on-site storage facilities to permit continued operation is discussed in Chapters 9, 10, and 11 of the Environmental Report.
In order to provide spent fuel storage until the Department of Energy begins to accept title to spent fuel under the requirements of the Nuclear Waste Policy Act of 1982, as amended in 1987, BGE built an Independent Spent Fuel Storage Installation (ISFSI) in compliance with Title 10 Code of Federal Regulations Part 72. Baltimore Gas and Electric Company chose the Nutech Horizontal Modular Storage (NUHOMS)-24P dry storage system designed by Transnuclear West (formerly Nutech Engineers, Inc.) for the Calvert Cliffs ISFSI. The NUHOMS-24P system is more fully described in Reference 1.2. The location of the ISFSI on the Calvert Cliffs site is shown on Figure 1.1-1.
Calvert Cliffs Nuclear Power Plant has reanalyzed the ISFSI to use Transnuclear NUHOMS-32P and NUHOMS-32PHB Dry Shielded Canisters (DSCs) to optimize its dry spent fuel storage capacity. The NUHOMS-32P and NUHOMS-32PHB DSC system stores eight more spent fuel assemblies than the NUHOMS-24P DSC using the same external and internal shell dimensions. The NUHOMS-32P and NUHOMS-32PHB DSC storage capacities are optimized by reducing the space between the locations of each fuel assembly and by slightly reducing the size of the storage locations.
Chapter 12 is a dedicated discussion of the use of the NUHOMS-32P DSC design and Chapter 13 is a dedicated discussion of the use of the NUHOMS-32PHB DSC design at CCNPP. Unless otherwise explicitly stated the information on the NUHOMS DSCs provided throughout this Updated Safety Analysis Report is applicable to the NUHOMS-24P DSC, the NUHOMS-32P DSC, and the NUHOMS-32PHB DSC.
The major difference between the NUHOMS-32P DSC and the NUHOMS-24P DSC is the internal basket assembly. The NUHOMS-32PHB DSC basket is similar to the NUHOMS-32P DSC basket with the exception that solid aluminium rails are used in the NUHOMS-32PHB DSC basket.
The DSC is loaded into a transfer cask for transporting to and from the horizontal storage module (HSM). The same transfer cask is used for on-site transfer of either a NUHOMS-24P DSC or a NUHOMS-32P DSC. Likewise, the same HSM design is used for the storage of either a NUHOMS-24P DSC or a NUHOMS-32P DSC, however, the latter may also be stored in a modular high burnup horizontal storage module (HSM-HB). When moving a NUHOMS-32PHB DSC the transfer cask is modified to allow for forced cooling. See Figure 1.3-9 for transfer cask forced cooling assembly. Also, the NUHOMS-32PHB DSCs are only stored in the HSM-HBs.
The NUHOMS system provides safe interim storage for irradiated fuel assemblies. The fuel assemblies are confined in a helium atmosphere by a stainless steel canister. The canister is protected and shielded by a massive concrete module. Decay heat is removed by thermal CALVERT CLIFFS ISFSI USAR 1.1-1 Rev. 26
radiation, conduction, and convection from the canister to an air plenum inside the concrete module. Air flows through this internal plenum by natural draft convection.
The canister containing irradiated fuel assemblies is transferred from the spent fuel pool to the concrete module in a transfer cask. The cask is precisely aligned and the canister is inserted into the module by means of a hydraulic ram.
The NUHOMS system is a totally passive installation that is designed to provide shielding and safe confinement of irradiated fuel. The DSC and HSM/HSM-HB have been designed to withstand certain accidents.
The fuel assemblies to be stored in the ISFSI are located in the Calvert Cliffs spent fuel pool and were irradiated only in the Calvert Cliffs reactors. Twenty-four fuel assemblies are stored in each NUHOMS-24P DSC, 32 fuel assemblies are stored in each NUHOMS-32P DSC or NUHOMS-32PHB, and one DSC is stored in each concrete module. The license allows construction and operation of a total of 132 modules. Of these, 72 HSMs were poured in place and the remaining 60 HSM-HBs will be of modular construction. The NUHOMS-32PHB will not be stored in the poured in place HSMs, but are to be stored in the HSM-HBs only. These modules will be built incrementally, as needed, to match CCNPPs requirements for additional storage. The first 72 modules built were poured in place (HSM) and the remaining will be of modular construction (HSM-HB). Operation of the facility will continue for up to 20 years under the initial license and continue under license renewal as necessary until a permanent facility is available for spent fuel disposal, or for a maximum of 40 years under the renewed license period (60 years, total). As defined in Table 1.2-2 of Reference 1.2, the minimum design life of the facility is 50 years.
Reference Figures 1.1-2 and 1.1-3 for ISFSI Cask Loading Map and Database.
CALVERT CLIFFS ISFSI USAR 1.1-2 Rev. 26
1.2 GENERAL DESCRIPTION OF INSTALLATION 1.2.1 GENERAL DESCRIPTION The ISFSI provides for the horizontal dry storage of irradiated fuel assemblies in a concrete module. The principal components are a concrete HSM and a stainless steel DSC with an internal basket which holds the fuel assemblies. Each HSM contains one DSC. Each NUHOMS-24P DSC contains 24 fuel assemblies. Each NUHOMS-32P or NUHOMS-32PHB DSC contains 32 fuel assemblies.
The initial license limits spent fuel storage capacity to 1,111.68 TeU of spent fuel assemblies.
The renewed license raises the spent fuel storage capacity to 1,558.27 TeU to allow for storage of fuel generated over the 60 year licensed lifetime of Calvert Cliffs Unit 1 and Unit 2.
The initial phase of construction includes 72 HSMs. Additional modules can be added as required on separate foundations without impact to the preceding or subsequent modules. Analyses for structural and foundation requirements provide for constructing poured in place modules in a 2x6 array. Analyses for structural and foundation requirements provide for constructing the pad to accommodate HSM-HB modules in two 2x12 arrays and one 1x12 array. The layout of the ISFSI is shown on Figure 1.2-1.
In addition to these primary components, the Calvert Cliffs ISFSI also requires transfer equipment to move the DSCs from the spent fuel pool (where they are loaded with spent fuel) to the HSMs where they are stored. This transfer system consists of a transfer cask, a hydraulic ram, a cask skid mounted on either a self-propelled modular transporter (SPMT) or a trailer pulled with a truck. This transfer system interfaces with the existing Calvert Cliffs spent fuel pool, the cask handling crane, and the site layout (i.e., roads and topography).
1.2.2 PRINCIPAL SITE CHARACTERISTICS The ISFSI is located on the CCNPP site near Lusby, MD. Calvert Cliffs Nuclear Power Plant, LLC owns and Exelon Generation operates two 2737 MWT nuclear generating units on the Calvert Cliffs site. The ISFSI is located outside the protected area, but within the owner controlled area approximately 2300' southwest of the plant (Figure 1.1-1).
1.2.3 PRINCIPAL DESIGN CRITERIA The principal design criteria and parameters for the Calvert Cliffs ISFSI are shown in Table 1.2-1 and Table 1.2-3. A detailed description of the criticality safety, shielding, structural, and decay heat removal features of the storage system is presented in the following in Reference 1.2 (NUHOMS-24P), Chapter 12 (NUHOMS-32P), and Chapter 13 (NUHOMS-32PHB).
Design features of the NUHOMS system important to safe operation are outlined in Reference 1.2 and USAR, Chapters 12 and 13. Changes to any of these design features will be implemented only after conducting a safety review in accordance with 10 CFR 72.48 or a license amendment is granted by the Nuclear Regulatory Commission.
CALVERT CLIFFS ISFSI USAR 1.2-1 Rev. 26
1.2.4 OPERATING AND FUEL HANDLING SYSTEMS The major operating systems of the ISFSI are those required for fuel handling in the Auxiliary Building and transport of the transfer cask and DSC from the spent fuel pool to the ISFSI. The primary design parameters for these systems are listed in Table 1.2-2 and Table 1.2-4. The majority of the fuel handling operations involving the transfer cask which take place in the Auxiliary Building (i.e., fuel loading, drying, trailer loading, etc.) utilize standard techniques at Calvert Cliffs for spent fuel shipment. The remaining operations (canister seal welding, transfer cask-HSM alignment, and DSC transfer) are unique to the ISFSI.
1.2.5 SAFETY FEATURES The principal safety features of the ISFSI are inherent in the design of the DSC and the HSM. These safety features include protection of the spent fuel from the consequences of extreme environmental phenomena, redundant DSC closure welds to ensure containment, and a range of operational design features to maintain occupational dose as low as reasonably achievable. Additional details of the safety features of the NUHOMS System are presented in Reference 1.2 and USAR, Chapters 12 and 13.
1.2.6 RADIOACTIVE WASTE AND AUXILIARY SYSTEMS No radioactive waste is generated during normal storage operations and, because of the passive nature of the ISFSI, no auxiliary systems are required for storage. The DSC Vacuum Drying System, used during initial canister closure operations, is an auxiliary system which pumps contaminated water from the DSC to plant processing systems or back to the spent fuel pool. It is also used to evacuate the DSC and backfill it with helium. The existing Calvert Cliffs Auxiliary Building processing systems are used to handle water and gasses which are drained and vented from the cavity of the DSC during the drying process.
CALVERT CLIFFS ISFSI USAR 1.2-2 Rev. 26
TABLE 1.2-1 DESIGN PARAMETERS FOR THE CALVERT CLIFFS ISFSI USING A NUHOMS-24P OR NUHOMS-32P DSC GENERAL DESIGN REQUIREMENTS Capacity (Fuel Assemblies/Canister) NUHOMS-24P DSC 24 Pressurized Water Reactor Assemblies NUHOMS-32P DSC 32 Pressurized Water Reactor Assemblies Reference Fuel Assembly Parameters:
Burnup: Max. Assembly Average 47,000 MWD/MTU (NUHOMS-24P) 52,000 MWD/MTU (NUHOMS-32P)
Initial Enrichment (Maximum) 4.5 w/o U235 Initial Uranium Content NUHOMS-24P 386 kg/Assembly (Nominal)
NUHOMS-32P 400 kg/Assembly (Maximum)
Decay Heat Power (Maximum) 0.66 kW/Assembly Cooling Time As Required for Decay Heat Limit Fuel Rod Array Combustion Engineering 14x14 Assembly Weight (Maximum) 1,450 lbs Maximum Assembly Envelope 8.25 inches by 8.25 inches Effective Multiplication Factor:
Normal NUHOMS-24P Keff < 0.95 NUHOMS-32P Keff < 0.95 Off-Normal NUHOMS-24P Keff < 0.98 NUHOMS-32P Keff < 0.95 Internal DSC Atmosphere Helium 99.995% pure Ambient Temperature Range -3°F to 103°F Solar Heat Load: Maximum 127 Btu/hr-ft2 Average 82 Btu/hr-ft2 Maximum Dose at HSM Surface During 20 mrem/hr Storage (Away from Openings)
Maximum Dose at HSM Door and 100 mrem/hr Penetrations Peak Long-Term Clad Temperature 635°F Peak Short-Term Clad Temperature 1,058°F Credit for Burnup Criticality Analysis NUHOMS-24P Based on 1.8% equivalent initial enrichment NUHOMS-32P - N/A(a)
Maximum Assembly Length (Includes less than 158.0" Radiation Growth)
Active Fuel Length 136.7" (a) See Section 12.3.3.4.
CALVERT CLIFFS ISFSI USAR 1.2-3 Rev. 26
TABLE 1.2-2 PRIMARY DESIGN PARAMETERS FOR THE NUHOMS-24P or NUHOMS-32P DSC TRANSFER SYSTEM
[References 1.4, 1.7, and 1.8]
SYSTEM PARAMETER VALUE Transfer Cask Nominal Cavity Diameter 68" Nominal Cavity Length 173.5",
174.25 (with lid spacer)
Payload 95,000 lbs (Maximum)
Decay Heat Rejection (Maximum) 21.12 kW (0.66 kW/Assembly)
(NUHOMS-32P DSC)
Shielding (Surface Dose, Combined 200 mrem/hr (Maximum)
Neutron and Gamma, Away from Penetrations)
Transfer Cask Liftable by Yoke Using Crane 109.25 tons Gross Lift Handling Rotates on Lower Trunnions Vertical (Maximum) to Horizontal when Lowered by Crane Transfer Cask Skid Payload 215,000 lbs (Maximum)
Transfer Trailer Payload (Cask + Skid) 240,000 lbs (Maximum)
Dead Weight 40,000 lbs (Maximum)
Gross Vehicle Weight 280,000 lbs (Maximum)
Limiting Cask Height 80" (Maximum)
CALVERT CLIFFS ISFSI USAR 1.2-4 Rev. 26
TABLE 1.2-3 DESIGN PARAMETERS FOR THE CALVERT CLIFFS ISFSI USING A NUHOMS-32PHB DSC GENERAL DESIGN REQUIREMENTS Capacity (Fuel Assemblies/Canister) 32 Pressurized Water Reactor Assemblies Reference Fuel Assembly Parameters:
Burnup: Max. Assembly Average 62,000 MWD/MTU Initial Enrichment (Maximum) 5.0 w/o U235 for Basket Type B 4.75 w/o U235 for Basket Type A Initial Uranium Content 475 kg/Assembly Decay Heat Power (Maximum) 0.8 kW/Assembly zones 1 and 4 1.0 kW/Assembly zones 2 and 3 Cooling Time As required for Decay Heat Limit Fuel Rod Array Combustion Engineering 14x14 VAP 14x14 AREVA 14x14 Assembly Weight (Maximum) 1375 lbs Maximum Assembly Envelope 8.25 by 8.25 Effective Multiplication Factor:
Normal Keff < 0.95 Off-Normal Keff < 0.95 Internal DSC Atmosphere Helium 99.995% pure Ambient Temperature Range -3°F to 103°F Solar Heat Load: Maximum 127 Btu/hr-ft2 Average 82 Btu/hr-ft2 Maximum Dose at HSM-H Surface During 20 mrem/hr Storage (Away from Openings)
Maximum Dose at HSM Door and 100 mrem/hr Penetrations Peak Long-Term Clad Temperature 752°F (400°C)
Peak Short-Term Clad Temperature 1,058°F (570°C)
Credit for Burnup Criticality Analysis N/A Maximum Assembly Length (Includes < 158.0 Radiation Growth)
Active Fuel Length 136.7 References 13.21, 13.22, and 13.26 for Thermal parameters.
Reference 13.15 for Structural parameters.
CALVERT CLIFFS ISFSI USAR 1.2-5 Rev. 26
TABLE 1.2-4 PRIMARY DESIGN PARAMETERS FOR THE NUHOMS-32PHB DSC TRANSFER SYSTEM
[References 1.12,1.13, 13.30]
SYSTEM PARAMETER VALUE Transfer Cask Nominal Cavity Diameter 68 Nominal Cavity Length 173.5 174.5 (with lid spacer)
Payload 95,000 lbs Decay Heat Rejection 29.6 kW [1.0 kW/Assembly -
(Maximum)]
Shielding (Surface Dose, Combined 250 mrem/hr (Maximum)
Neutron and Gamma, Away from Penetrations)
Transfer Cask Liftable by Yoke Using Crane 109.25 tons gross lift Handling Rotates on Lower Trunnions Vertical (Maximum) to Horizontal when Lowered by Crane Transfer Cask Skid Payload 215,320 lbs (Maximum)
SPMT Payload (Cask + Skid) 249,320 lbs (Maximum)
Dead Weight 50,500 lbs Gross Vehicle Weight 299,820 lbs Limiting Cask Height 80" (Maximum)
CALVERT CLIFFS ISFSI USAR 1.2-6 Rev. 26
1.3 GENERAL SYSTEMS DESCRIPTIONS The following subsections briefly describe the principal systems and components and their operation. The major systems, subsystems, and components of the Calvert Cliffs ISFSI are shown in Table 1.3-1 and Table 1.3-2.
1.3.1 SYSTEMS DESCRIPTIONS The components of storage at the ISFSI are the DSC and the HSM/HSM-HB.
Additional systems required for the DSC closure and transfer include the transfer cask, the skid and skid positioning system, the trailer or the SPMT, the hydraulic ram system, and the DSC vacuum drying system and the forced cooling system as required.
1.3.1.1 Dry Shielded Canister Design 1.3.1.1.1 NUHOMS-24P DSC The design of the generic NUHOMS-24P DSC is described in detail in Reference 1.2. The Calvert Cliffs DSC is very similar to the referenced design with revisions as necessary to accommodate a slightly different fuel assembly design.
The main component of construction of the DSC is a stainless steel cylindrical containment vessel.
The component subassemblies of the NUHOMS-24P DSC are listed in Table 1.3-1 and shown on Figure 1.3-1. The internal basket assembly is comprised of 24 guide sleeves supported by spacer disks at intervals corresponding, for the most part, to the fuel assembly spacer grids. For a few of the fuel assemblies, the spacer grids were found not to be in complete alignment with the NUHOMS-24P DSC spacer disks. Such misalignments were evaluated structurally, and found to be able to withstand normal and cask drop loads.
Support rods maintain the spacer disk location. All canister structural components are fabricated from type 304 stainless steel, except the spacer disks and support rods may be fabricated from aluminum coated carbon steel. Lead gamma shielding is used in both the top and bottom end shield plugs.
The principal differences between the Calvert Cliffs NUHOMS-24P DSC and the generic DSC design are: the addition of one spacer disk for a total of nine to accommodate the Calvert Cliffs fuel which has nine spacer grids; thinner spacer disks with wider ligaments; an additional 1/2" of lead in both shield plugs; and a shorter overall length accounting for the shorter fuel assembly design.
Criticality safety for the NUHOMS-24P DSC, during wet loading operations, is maintained through the geometric separation of the fuel assemblies within the internal basket assembly, the inherent neutron absorption capability of the stainless steel guide sleeves, and the proper selection of sufficiently depleted fuel assemblies. The NUHOMS-24P DSC has only been analyzed for storage in the HSM.
CALVERT CLIFFS ISFSI USAR 1.3-1 Rev. 26
1.3.1.1.2 NUHOMS-32P DSC The NUHOMS-32P DSC design increases the number of stainless steel guide sleeves to 32 (one for each spent fuel assembly) and uses an egg-crate design made of stainless steel and aluminum (borated and unborated plates) to support the guide sleeves. This egg-crate design is similar to the Transnuclear TN-68 basket assembly currently in use at a number of nuclear plants. Both the guide sleeves and the egg-crate components run the full length of the DSC cavity.
This allows the guide sleeves to be in contact with the egg-crate components over the whole length of the DSC cavity versus only at spacer discs in the NUHOMS-24P DSC design. As with the NUHOMS-24P DSC design, the basket assembly is not attached to the DSC shell walls or cover plates.
Other differences are the relocation of the vent and siphon ports. They have been moved from the DSC shell wall (in NUHOMS-24P DSC) to the DSC top shield plug (in NUHOMS-32P DSC) to improve the welding, blowdown, and vacuum drying operations. The NUHOMS-32P DSC lifting fixture device is different than the lifting eyes of the NUHOMS-24P DSC (Reference 1.9). The top shield plug for the NUHOMS-32P DSC is different than the NUHOMS-24P DSC top shield plug. The design change to the top shield plug involves a reduction in the lead shield thickness, and an increase in the outer steel plate thicknesses.
Criticality Safety for the NUHOMS-32P DSC is maintained through fixed neutron absorbers in the NUHOMS-32P basket and increasing the soluble boron in the spent fuel pool water to a concentration of 2,450 ppm.
All the major steps for loading and unloading a DSC (welding, vacuum drying, etc.) are the same for the NUHOMS-24P DSC and the NUHOMS-32P DSC systems. The DSC is loaded into a transfer cask for transporting to and from the HSM/HSM-HB. The NUHOMS-32P DSC may be stored in either the HSM or HSM-HB.
1.3.1.1.3 NUHOMS-32PHB DSC The design of the NUHOMS-32PHB is very similar to the design of the NUHOMS-32P with revisions as necessary to accommodate higher burnup discharged spent fuel assemblies. The NUHOMS-32PHB basket periphery area will contain solid aluminum rails to increase the heat transfer properties of the DSC.
Criticality safety for the NUHOMS-32PHB is similar to that of the NUHOMS-32P and is maintained through fixed neutron CALVERT CLIFFS ISFSI USAR 1.3-2 Rev. 26
absorbers in the NUHOMS-32PHB basket. Also, the soluble boron concentration in the spent fuel pool water will be maintained to at least 2,450 ppm during cask loading operations in the spent fuel pool.
The major steps for loading and unloading a DSC (welding, vacuum drying, etc.) are the same for the NUHOMS-24P DSC, the NUHOMS-32P DSC, and the NUHOMS-32PHB DSC systems. The DSC is loaded into a transfer cask for transporting to and from the HSM. However, the NUHOMS-32PHB is placed into a HSM-HB module for storage.
The NUHOMS-32PHB will not be loaded into one of the HSMs that were constructed before 2008.
1.3.1.2 Horizontal Storage Module The Calvert Cliffs ISFSI employs poured in place HSMs constructed in units of 12 configured in a 2x6 array for the first 72 modules, and modular construction HSM-HBs configured in two 2x12 arrays and one 1x12 array for the remaining modules.
1.3.1.2.1 HSM Modules The HSM major design features are similar to the design presented in Reference 1.2. Major design features include items such as the overall module layout, size, wall thicknesses, DSC support rails layout and location, and air inlet and outlet configurations and sizes. There are differences in the HSM design details compared to those presented in Reference 1.2, including the following:
A. The DSC rail support beam at the front of the module in the Reference 1.2 design was eliminated for simplification of the rail support scheme. The front end of the rails were changed to be supported directly by the front wall of the module using anchored angles similar to those used to support the rail support beams at the middle and rear of the module.
B. The amount of shear reinforcement was changed to be consistent with the specific design parameters applicable to the Calvert Cliffs ISFSI HSMs.
C. The foundation size was reduced to simplify construction.
D. The DSC seismic restraint was redesigned to make it significantly lighter than the Reference 1.2 design and therefore easier to handle. This reduces personal radiation exposure for placement of the restraint in the module after insertion of the DSC.
CALVERT CLIFFS ISFSI USAR 1.3-3 Rev. 26
E. The DSC support rails were redesigned from WT 6x115 to WF 8x40 to employ a more efficient section which reduces weight, resulting in reduced material and construction costs.
F. The DSC support assembly cross-member section was redesigned from W 10x68 to W 8x48 to employ a more efficient, lighter weight section.
G. The module rebar design was revised to eliminate unnecessary rebar.
H. The HSM door design was revised to incorporate additional radiological shielding material.
The HSMs are constructed in place at the ISFSI with pairs of 2x6 arrays placed end to end. The arrangement of the HSMs at the ISFSI is shown in Figure 1.2-1. Each array of 12 HSMs is constructed on a common reinforced concrete foundation slab. The HSM is designed to provide neutron and gamma shielding to achieve a nominal 20 mrem/hr contact dose rate.
Nominal contact dose rates at the HSM access door and vents are designed to be less than 100 mrem/hr.
Three foot thick end walls provide shielding on the sides of each HSM array. The front walls of the HSMs are thickened to 3-1/2. Two foot thick interior common walls provide shielding between modules to prevent scatter in adjacent modules during DSC loading and retrieval. The roof slab for the HSMs is 3 thick. An internal slab and roof caps are provided to shield the ventilation inlet and outlet openings.
The HSMs are independent, passive systems for the dry storage of irradiated fuel assemblies. Therefore, the HSMs are designed to ensure that normal operation and credible hazards do not impair their function. To this end, the HSMs are designed to withstand the following loads:
A. Winds and Tornado (including missile impact)
Regulatory Guide 1.76 B. Seismic CCNPP Updated Final Safety Analysis Report, Section 2.6 C. Flood CCNPP Updated Final Safety Analysis Report, Section 2.5 D. Snow and Ice American National Standards Institute A58.1-1982 E. Combined Loads (dead weight, live loads, thermal loads, creep effects) American Concrete Institute 349-85.
CALVERT CLIFFS ISFSI USAR 1.3-4 Rev. 26
1.3.1.2.2 HSM-HB Modules The HSM-HB to be used at CCNPP is a modified version of the HSM-H described in the Updated Final Safety Analysis Report for the Standardized NUHOMS and the NUHOMS HD systems (References 1.10 and 1.11). For CCNPP, the door and the spacer are modified to accommodate the diameter and length of the 32P DSC. While the HSM-HB module design is similar to the design of the poured inplace HSM, the following is a summary of the design differences which provide improved heat rejection and shielding capabilities:
- Use of a thicker roof (38 vs 3) provides improved shielding,
- Door is inset in HSM-HB opening, with increased thickness to provide improved shielding,
- Use of slotted plates and holes in the DSC support rails to increase airflow at the bottom portion of canister,
- Increased dose rates near inlet vent; decreased in all other analyzed locations,
- Increased height of the module to increase module cavity and stack height and to minimize air flow resistance in the module cavity,
- Optimized DSC support structure minimizes airflow resistance,
- Outlet vents repositioned from top front and back to top sides (opening shared by adjacent modules),
- Inlet vents repositioned from front bottom center to front bottom sides (opening shared by adjacent modules). Use of operational attenuation pipes improves inlet vent shielding.
The HSM-HBs will be prefabricated and assembled at the Calvert Cliffs ISFSI site whereas the current HSMs were poured in place. Each prefabricated HSM-HB is comprised of a base unit and roof unit assembled together to form a single module. The DSC is supported inside the HSM-HB by the DSC support structure. The DSC support structure (rail support assembly) is comprised of two rail sections, two slotted plates and two rail support plates. The rail support assembly provides support for the DSC during storage and acts as a sliding surface during DSC insertion and retrieval.
The modules sit on a reinforced concrete basemat at the ISFSI site.
Each HSM-HB is placed in contact with an adjacent HSM-HB to form a two 2x12 arrays and one 1x12 array. The air inlet vents extend through the front on both sides of the front wall.
The front wall and the rear wall of the base unit provide support for the rails and the rail extension flanges. The roof CALVERT CLIFFS ISFSI USAR 1.3-5 Rev. 26
unit rests on the front, rear, and side walls of the base unit.
The air outlet vents are provided in the roof unit. Similar to the current poured in place HSMs, flat panels are used as heat shields on the interior walls of the HSM-HB. The heat shields provide thermal protection for the HSM-HB concrete.
Finally, attenuation pipes are added, as an option, to the inlet vent screens to improve the shielding capabilities of the module.
The HSM-HB shield door consists of a rectangular steel plate at the front attached to a circular reinforced concrete block at the rear. Both the steel plate and concrete blocks fit the circular opening in the front wall. Studs are welded to the circular steel plate which provides anchors to the rear reinforced concrete block. The concrete door provides missile protection and shielding. End shield walls are provided at the ends of a module array to provide the required missile and shielding protection.
During DSC insertion/retrieval operations, the transfer cask is docked with the HSM-HB docking surface and mechanically secured to the embedments provided in the front wall. The embedments are equally spaced on either side of the HSM-HB access opening.
Storage of the NUHOMS-32P DSC in the HSM-HB is subject to the same controls and limitations as those of the HSM.
1.3.1.3 Transfer Cask The transfer cask used with the ISFSI provides radiological shielding during the DSC closure operations and during transfer of the DSC to the HSM/HSM-HB. To ensure structural integrity, the transfer cask also provides protection of the DSC against potential natural and operational hazards during transport and transfer of the DSC to the HSM/HSM-HB.
Both solid neutron and lead gamma shielding are incorporated into the transfer cask design. Figure 1.3-2 shows the major components of the transfer cask. The Calvert Cliffs transfer cask has a solid hydrogenous neutron shield in the outer annulus of the cask, and as a result the liquid neutron shield expansion tank of Reference 1.2 was deleted.
1.3.1.4 Transfer Equipment 1.3.1.4.1 Transfer Trailer The transfer trailer is used to transport the transfer cask skid and the loaded transfer cask from the Auxiliary Building to the ISFSI. The transfer trailer is an industrial heavy-haul trailer with pneumatic tires, hydraulic suspension and steering, and brakes on all wheels. The approach slab has adequate space for turning the transport trailer and tow vehicle. Four hydraulic jacks are incorporated into the transfer trailer design to provide vertical elevation adjustment for alignment of the CALVERT CLIFFS ISFSI USAR 1.3-6 Rev. 26
cask at the HSM. The transfer trailer is shown in Figure 1.3-3. It is pulled by a conventional tractor.
1.3.1.4.2 SPMT The Doerfer Companies Wheelift Self-Propelled Modular Transporter (SPMT), complete with Transfer Cask Support Skid (TCSS), is designed to accept a transfer cask filled with a DSC that is lowered onto the TCSS in a vertical orientation.
In the down-ending position the SPMT is lowered so that the TCSS rests on the pavement. The SPMT is shown in Figure 1.3-8.
The transporter is composed of four major systems: controls, power generation, hydraulic, and the drive system. Using these systems, an operator can manually position the vehicle to lift a maximum load of 125 tons. Operation is powered either by using building power through an umbilical cable (Shore) or by relying on diesel to fuel the engine (Gen) for electrical generation.
This transporter is designed to operate on smooth surfaces, such as concrete or asphalt, with a grade of no more that 6%
(loaded or unloaded).
The transporter is equipped with 12 articulating axle Wheelift assemblies, each of which is comprised of a large-bore hydraulic cylinder, two servo motors and gearboxes, and two 18 diameter x 12 wide urethane drive wheels coupled by chains and sprockets to the gearboxes. The center of the assembly contains a custom lift column designed to provide on-center rotation as well as lift and suspension functions.
The vehicle has 10 vertical stroke provided by the hydraulic cylinders to accommodate the clearance needed to drive under the load, and then lift and carry the load. Steering is accomplished by varying torques and speeds of the two servo motors on any given wheel set. Hard stops limit the modules rotation to approximately +140° to -50°, while software limits further reduce the rotational angle to preset limits depending on the mode of travel. The motors are designed to propel the module at speeds ranging from 0.0 to 90 FPM.
The SMPT includes optional snugging jacks. Calvert Cliffs chooses not to use the snugging jacks with the SPMT for the following reasons:
A. The SPMT employs solid tires, thus, there is no threat of the transfer trailer or DSC moving out of alignment due to the loss of air.
B. The SPMT design includes 32 solid wheels having 16 points of support via the 16 independent wheel modules (two wheels each).
CALVERT CLIFFS ISFSI USAR 1.3-7 Rev. 26
C. The SPMT hydraulic support system design makes a loss of hydraulic pressure highly unlikely. If any hydraulic system load zone incurs a hydraulic failure of any degree, the remaining zones are locked into position by all of the check valves being de-energized (fail safe condition) which prevents any of the remaining zones from losing pressure and lowering.
There are spring-applied check valves in each load zone which automatically close in any 1 of 3 instances:
- Upon the loss of power.
- When an E-Stop is depressed.
- Anytime a hydraulic deficiency or failure is detected anywhere in the hydraulic system (or any individual zone) by the programmable logic controller, a hydraulic fault is set and the check valves are de-energized (locked).
D. Any one of these conditions will prevent the load zones from losing pressure or lowering. Even if a slow leak occurred between the hydraulic cylinder and the check valve due to a loose fitting or bad cylinder seal, the resulting motion would be slow and controlled.
The likelihood of a catastrophic failure of a load zone is so remote it is considered a non-credible event.
1.3.1.5 Transfer Cask Skid and Positioning System 1.3.1.5.1 Transfer Trailer Cask Skid and Positioning System The transfer cask skid is essentially identical in design and operation to previous NUHOMS-24P system TCSSs. The skid is supported on lubricated bearing plates attached to the trailer deck and can be moved horizontally on the bearing plates by the hydraulic actuators of the skid positioning system. The skid is secured to the trailer deck in a travel lock position during cask loading and transport operations. The transfer cask skid is shown in Figure 1.3-4.
1.3.1.5.2 SPMT Skid and Positioning System The TCSS is a large weldment with a capacity of 118 tons, designed to hold the transfer cask and DSC during transfer, loading, and unloading operations. The TCSS includes aluminum bronze trunnion inserts and a Gleason Reel for electrical cable storage. This framework also supports the hydraulic ram cylinder assembly and a hydraulic tilt cylinder assembly. Each of these assemblies has chamfered locator blocks to guide each assembly into proper position when loading/connecting the hydraulic ram assembly to the TCSS.
CALVERT CLIFFS ISFSI USAR 1.3-8 Rev. 26
1.3.1.6 Hydraulic Ram System 1.3.1.6.1 Transfer Trailer Hydraulic Ram System The hydraulic ram consists of a double acting hydraulic cylinder with a capacity of 80,000 lb in either push or pull and stroke of 21'. The ram is supported during operation by a frame assembly attached to the bottom of the transfer cask and a tripod assembly resting on the concrete slab. The operational loads of the hydraulic ram are grounded through the transfer cask. The hydraulic ram system includes a grapple at the end of the piston which is used to engage a grapple ring on the DSC for retrieval operations. Figure 1.3-5 shows the hydraulic ram system.
1.3.1.6.2 SPMT Hydraulic Ram System Mounted to the TCSS, is a hydraulic and electric line connection plate. This connection plate houses the quick disconnect fittings for the ram and tilt hydraulic cylinders and for the grapple assembly cable.
The Hydraulic Ram Cylinder Assembly consists of the hydraulic ram cylinder and the grapple assembly. The hydraulic ram cylinder is a telescopic three stage double acting cylinder that can advance approximately 21 feet.
The Grapple Assembly consists of a 130 vdc motor, lead screw, toggle mechanism, two grapple fingers, and quick disconnect mounting. The grapple fingers are actuated by the dc motor and lead screw. The grapple assembly is used to secure the hydraulic ram cylinder to the DSC. Figure 1.3-9 shows the hydraulic ram cylinder connected to the SPMT.
1.3.1.7 Vacuum Drying System The vacuum drying system removes water and air from the DSC and fills it with helium. The vacuum drying system has four operational modes:
water removal, helium or air forced water removal, vacuum pumping, and helium backfilling.
1.3.1.8 Closure Welding System The DSC closure welds on the shield plug and the top cover plate are normally placed by a fully remote, automatic welding system. The system includes modular components and is designed for rapid setup. Welding operations are remotely controlled by an operator who views the progress of the weld through closed circuit television. The welding head is designed to permit rapid replacement with either a UT probe, or a plasma gouging torch which can be used to remove the shield plug and top cover plate closure welds. Manual welding may also be used for closure welds. The allowed duration of manual welding is limited by the ambient dose rate at the location of the welding (Reference 1.6).
CALVERT CLIFFS ISFSI USAR 1.3-9 Rev. 26
1.3.1.9 System Operation See Chapter 5 for a detailed description of the Calvert Cliffs ISFSI System Operation.
CALVERT CLIFFS ISFSI USAR 1.3-10 Rev. 26
TABLE 1.3-1 MAJOR SYSTEMS, SUBSYSTEMS, AND COMPONENTS OF THE CALVERT CLIFFS ISFSI FOR A NUHOMS-24P OR NUHOMS-32P DSC Dry Shielded Canister NUHOMS-24P DSC Basket NUHOMS-32P DSC Basket Guide Sleeves (24) Guide Sleeves (32)
Spacer Disks (9) Egg-Crate Support Rods (4) Peripheral Steel Rails DSC Shell With Bottom Shield Plug DSC Shell With Bottom Shield Plug Shield Plug (Top) Shield Plug (Top)
Cover Plates (Top and Bottom) Cover Plates (Top and Bottom)
Siphon and Vent Ports Siphon and Vent Ports Ram Grapple Ring Ram Grapple Ring Horizontal Storage Module Reinforced Concrete Walls, Roof, Basemat, and Foundation DSC Structural Steel Support Assembly DSC Seismic Retainer Cask Docking Flange and Tie-Down Restraints Heat Shield Shielded Front Access Door and Door Supports Ventilation Air Openings (One Inlet, Two Outlets)
Shielded Ventilation Air Inlet Plenum Ventilation Air Outlet Shielding Blocks Lightning Protection System Cask Lifting Yoke Transfer Cask Cask Structural Shell Assembly Bolted Top Head Assembly Upper Lifting Trunnions Lower Tilting Trunnions Lead Gamma Shielding Solid Neutron Shielding Ram Access Penetration Cover Plate Ram Access Penetration Shield Plug Assembly Ram Mounting Frame Transfer Trailer* and Skid Heavy Industrial-Grade Trailer Cask Support Skid Skid Positioning and Alignment System Hydraulic Ram System Hydraulic Cylinder Rear Tripod Support Frame Grapple Assembly Vacuum Drying System Automated Remote Closure Welding System
- The SPMT may be used in place of the Transfer Trailer.
CALVERT CLIFFS ISFSI USAR 1.3-11 Rev. 26
TABLE 1.3-2 MAJOR SYSTEMS, SUBSYSTEMS, AND COMPONENTS OF THE CALVERT CLIFFS ISFSI FOR A NUHOMS-32PHB DSC Dry Shielded Canister NUHOMS-32PHB DSC Basket Guide Sleeves (32)
Egg-Crate Peripheral Steel Rails DSC Shell with Bottom Shield Plug Shield Plug (Top)
Cover Plates (Top and Bottom)
Siphon and Vent Ports Ram Grapple Ring Horizontal Storage Module (HSM-HB)
Reinforced Concrete Walls, Roof, Basemat, and Foundation DSC Structural Steel Support Assembly DSC Seismic Retainer Cask Docking Flange and Tie-Down Restraints Heat Shield Shielded Front Access Door and Door Supports Ventilation Air Openings (One Inlet, Two Outlets)
Shielded Ventilation Air Inlet Plenum Ventilation Air Outlet Shielding Blocks Lightning Protection System Cask Lifting Yoke Transfer Cask Cask Structural Shell Assembly Bolted Top Head Assembly Upper Lifting Trunnions Lower Tilting Trunnions Lead Gamma Shielding Solid Neutron Shielding Ram Access Penetration Cover Plate Ram Access Penetration Shield Plug Assembly Ram Mounting Frame Self-Propelled Horizontal Cask Transporter and Skid*
Self-Propelled Horizontal Cask Transporter Cask Support Skid Skid Positioning and Alignment System Hydraulic Ram System Hydraulic Cylinder Rear Tripod Support Frame Grapple Assembly Vacuum Drying System Automated Remote Closure Welding System
- The self-propelled horizontal cask transporter and skid may be used with the NUHOMS-24P and NUHOMS-32P DSC.
CALVERT CLIFFS ISFSI USAR 1.3-12 Rev. 26
1.4 IDENTIFICATION OF AGENTS AND CONTRACTORS The prime contractor for design, analysis, and component supply for the Calvert Cliffs ISFSI was Transnuclear (formerly Nutech Engineers, Inc.), of Columbia, MD. The ISFSI is owned by CCNPP, LLC and operated by Exelon Generation. Construction of the ISFSI is the responsibility of an approved construction contractor. For the poured in place HSMs, licensing support, geotechnical engineering, and Quality Assurance Program revisions were performed by Duke Engineering & Services, Inc., utilizing Duke Power Company personnel experienced on the Oconee Nuclear Station ISFSI. Subsurface investigations at the ISFSI were performed by Law Engineering Testing Company.
Geotechnical, civil, structural, mechanical, and electrical engineering support for the installation of the HSM-HB modules was provided by Sargent & Lundy LLC and MACTEC Engineering and Consulting, Inc. (formerly Law Engineering Testing Company). Subsurface analysis for the installation of the HSM-HB modules was performed by Sargent & Lundy LLC.
CALVERT CLIFFS ISFSI USAR 1.4-1 Rev. 22
1.5 MATERIAL INCORPORATED BY REFERENCE The Topical Reports for the Nutech Horizontal Modular Storage Systems for Irradiated Nuclear Fuel, (NUH-002, Revision 1A, July 1989) Reference 1.2, and (NUH-001, Revision 1A, June 1986)
Reference 1.3, are hereby incorporated into this document by reference and referred to by Section in Table 1.5-1.
CALVERT CLIFFS ISFSI USAR 1.5-1 Rev. 8
TABLE 1.5-1 SECTION REFERENCE FOR NUHOMS TOPICAL REPORTS SAR SECTIONS SUBMITTAL IN WHICH TITLE REPORT NO. DATE REFERENCED Topical Report for the NUH-002, Revision 1A, July 14, 1989 1.1, 1.2, 1.3, 1.5, Nutech Horizontal Modular July 1989 1.6, 3.1, 3.2, Storage System for 3.3, 4.1, 4.2, Irradiated Nuclear Fuel, 4.7, 7.1, 7.2, NUHOMS-24P, Nutech 7.3, 7.4, 8.1, Engineers, Inc. 8.2 Topical Report for the NUH-001, Revision 1A, June 27, 1986 7.1 Nutech Horizontal Modular June 1986 Storage System for Irradiated Fuel, NUHOMS-07P, Nutech Engineers, Inc.
CALVERT CLIFFS ISFSI USAR 1.5-2 Rev. 26
1.6 REFERENCES
1.1 Deleted 1.2 Topical Report for the Nutech Horizontal Modular Storage System for Irradiated Nuclear Fuel, NUHOMS-24P, Nutech Engineers, Inc., NUH-002, Revision 1A, July 1989 1.3 Topical Report for the Nutech Horizontal Modular Storage System for Irradiated Fuel, NUHOMS-07P, Nutech Engineers, Inc., NUH-001, Revision 1A, June 1986 1.4 Letter from Mr. G. C. Creel (BGE) to Director, Office of Nuclear Material Safety and Safeguards (NRC), dated December 20, 1990, Response to NRC's Comments on the Safety Analysis Report (SAR) for BGE's License Application for Calvert Cliffs Independent Spent Fuel Storage Installation (ISFSI) 1.5 Deleted 1.6 CCNPP Calculation CA05924, Calvert Cliffs ISFSI/NUHOMS-24P Radiation Dose Rates for Cask Loading and Transfer 1.7 CCNPP Calculation CA06297, Transfer Thermal Analysis, 103°F Ambient 1.8 CCNPP Calculation CA06329, NUHOMS-32P - Transfer Cask Structural Analysis 1.9 CCNPP Drawing 84227SH0001, NUHOMS-32P DSC Parts List - DSCs CEG32P-L049 thru CEG32P-L072 CCNPP Drawing 84266SH00010, NUHOMS-32P DSC Parts List - DSC CEG32P-L073 thru CEG32P-L078 1.10 Transnuclear, Inc., Updated Final Safety Analysis Report for the Standardized NUHOMS Horizontal Modular Storage System for Irradiated Nuclear Fuel, NRC Docket No. 72-1004, Transnuclear Document No. NUH-003, Revision 11 1.11 Transnuclear Inc., Updated Final Safety Analysis Report for the NUHOMS HD Horizontal Modular Storage System for Irradiated Nuclear Fuel, NRC Docket No. 72-1030, Revision 2 1.12 CCNPP Calculation CA10167, NUHOMS 32PHB Weight Calculation of DSC/TC System with Lid Spacer 1.13 ECP-16-000551, Allow optional shimming for SPMT TC skid in case needed to maintain proper skid elevation for inserting DSC into HSM CALVERT CLIFFS ISFSI USAR 1.6-1 Rev. 26