Earlier NAC Engineering Projects

Paducah Tiger Overpack (PTO) Accident Analysis (1998 - 2002):

Lockheed Martin Utility Services Inc. (LMUS), as the agent for the United States Enrichment Corporation (USEC), was responsible for the operation and maintenance of the Paducah and Portsmouth gaseous diffusion plants. In this capacity, LMUS frequently requires engineering design and analysis in support of ongoing operation and maintenance activities. NAC performed detailed finite analysis modeling and analyses of the PTO during hypothetical accident conditions as required by 10 CFR 71. The PTO is used for shipping the 48X UF6 cylinder. These analyses were used as the basis for USEC justification to the NRC for continued shipping operations using the PTO.

Subsequently, LMUS and USEC needed to develop a revised SAR for PTO re-certification and contracted with NAC for that work. The initial phase of that project reviewed the licensed SAR, and developed draft revisions and supporting documentation for the existing PTO design. NAC also identified technical issues and developed a plan to produce a revised SAR that would meet NRC requirements. In the next phase, the SAR was revised to meet NRC Regulatory Guide 7.9 requirements. Finally, the revised SAR was submitted and the PTO was successfully re-certified. 

NAC Californium Transport System (1996 - present):

This contract from Lockheed Martin Energy Research Corporation (LMER) called for NAC to design and fabricate a system for packaging and transporting transuranic material (Californium) from the Oak Ridge National Laboratory (ORNL) to domestic and international customers. NAC will design and deliver the transport cask and provide a customized transport trailer. The neutron shielding requirements for Californium, which is used as a reactor startup source and in industrial and medical applications, greatly exceed those for commercial spent fuel. NAC will provide an economical cask called the NAC-CTS (Californium Transport System) to meet these requirements. The cask is a right-cylindrical design, with truncated cone-shaped ends. The design also calls for special high-performance, fire-resistant neutron shielding materials. 

L-Basin Project-Savannah River Site (SRS) Shielded Transfer System (1996 -1999):

NAC designed a cask handling system for remote and automated unloading of spent fuel transportation casks at the SRS L-Basin. The L-Basin lacks sufficient water depth to handle the length of typical truck transportable casks requiring the installation of alternate capability. NAC designed the system, prepared fabrication specifications and assisted with installation and checkout at SRS. The system provides high caliber features for shielding of personnel, remote monitoring, and automated operation. 

K-Basin Project (1995 -2000):

NAC International served on the team originally selected to design, fabricate and deliver cask and transportation systems to remove spent nuclear fuel from DOE storage basins at Hanford, Washington. The project involved developing the systems to remove 2,300 metric tons of deteriorating spent nuclear fuel from the water-filled basins near the Columbia River and transporting the fuel to a dry storage facility near the center of the Hanford site. NAC's work included design and fabrication of the operations support equipment needed to load the canistered spent nuclear fuel into the transport casks.

DE&S Hanford Inc. also selected NAC to complete the final design and fabrication of the Multiple Canister Overpack (MCO) loading system for Hanford. The MCO loading system transfers baskets with spent fuel from the staging area into the MCO. Expanding on NAC's previous conceptual design, NAC integrated the individual components into the final system design as part of the Hanford spent fuel cask transportation system.