ML22077A770

Enclosure 1 - Proposed Technical Specification Changes Magnastor, Amendment 12

ML22077A770
Person / Time
Site:	07201031
Issue date:	03/31/2022
From:	NAC International
To:	Office of Nuclear Material Safety and Safeguards
Shared Package
ML22077A768	List: ML22077A769 ML22077A770
References
ED20220032
Download: ML22077A770 (5)

Text

Enclosure 1 Proposed Technical Specification Changes MAGNASTOR, Amendment 12 (Docket No 72-1031)

NAC International March 2022

Page 1 of 2 MAGNASTOR Certificate of Compliance, Amendment 9 Description, 4th Paragraph The concrete cask is the storage overpack for the TSC and provides structural support, shielding, protection from environmental conditions, and natural convection cooling of the TSC during long-term storage. The concrete cask body is a reinforced concrete (Type II Portland cement) structure with a carbon steel inner liner. The liner inner diameter incorporates standoffs to minimize impact loads on the TSC and to maintain convective heat flow paths under accident conditions. The concrete cask has an annular air passage to allow a passive convection air flow around the TSC. The air inlets and outlets are offset in elevation from the TSC to minimize radiation streaming. The spent fuel decay heat is transferred from the fuel assemblies to the TSC shell using pressurized helium circulated by convection through the fuel basket, conduction and radiation. Heat flows by convection from the TSC shell to the circulating air and by radiation from the TSC shell to the concrete cask liner. The heated air is exhausted, by convective flow, through the concrete cask air outlets. The top of the concrete cask is closed by a carbon steel lid with concrete shielding and is bolted in place.

Technical Specification, Appendix A, Section 1.1 CONCRETE CASK The CONCRETE CASK is the vertical storage module that receives, holds and protects the sealed TSC for storage at the ISFSI. The CONCRETE CASK passively provides the radiation shielding, structural protection, and heat dissipation capabilities for the safe storage of spent fuel in a TSC. Closure for the CONCRETE CASK is provided by the CONCRETE CASK LID.

CONCRETE CASK LID The CONCRETE CASK LID is a thick concrete and steel closure for the CONCRETE CASK. The CONCRETE CASK LID precludes access to the TSC and provides radiation shielding.

Technical Specification (TS) Appendix A, Section 4.2 4.2 Codes and Standards The American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code), 2001 Edition with Addenda through 2003,Section III, Subsection NB, is the governing Code for the design, material procurement, fabrication, and testing of the TSC.

The ASME Code, 2001 Edition with Addenda through 2003,Section III, Subsection NG, is the governing Code for the design, material procurement, fabrication and testing of the spent fuel baskets.

The American Concrete Institute Specifications ACI-349 and ACI-318 govern the CONCRETE CASK design and construction, respectively.

Page 2 of 2 The concrete used in the construction of the CONCRETE CASK LID, at minimum, shall be of a commercial grade ready-mix type that can develop a density 140 pcf. Verification of the minimum density shall be performed using pre and post pour weight measurements. There is no minimum compressive strength requirement for the concrete. Concrete placement shall be in a dry and clean cavity or form with procedures and equipment that ensure the concrete placed is thoroughly consolidated and worked around any reinforcement and/or embedded fixtures and into the corners of the cavity or form. Concrete curing shall be protected from environmental extremes of heat and cold unless admixtures are used as deemed necessary.

The American National Standards Institute ANSI N14.6 (1993) and NUREG-0612 govern the TRANSFER CASK

design, operation, fabrication, testing, inspection, and maintenance.

Potential Concrete Radial Shrinkage MCNP6 Evaluation MAGNASTOR, Amendment 12 (Docket No 72-1031)

NAC International March 2022

Page 1 of 1 NAC PROPRIETARY INFORMATION REMOVED NAC PROPRIETARY INFORMATION REMOVED