David Wise
Director of Commercial Programs
Nuclear Fuel Services, Inc.

This paper is a discussion of the distinguishing capabilities of the Model 6400 Super Tiger Type B Container for shipping plutonium bearing wastes, specifically ²³⁸Pu bearing wastes. Those capabilities and features include:

1. The ability to safely and compliantly transport up to 200 grams per shipment of heat generating ²³⁸Pu bearing waste materials. Other currently certified containers are limited to a significantly lower quantity of these materials.
2. A demonstrated twenty five year history of safe and compliant operation. The container also has a distinguished recent history of Pu shipments. During the past five years, over 125 shipments of ^238PPu and ²³⁹Pu bearing Decontamination and Decommissioning (D&D) wastes have been safely shipped using the Super Tiger overpack.
3. The container is easily utilized and requires no capital investment to load and unload. Sites having routine drum handling capability can easily train and set up to load and unload the package in as few as two days. Operator training at user sites typically requires less than one day with one additional day to package and manifest the shipment.

There are significant technical, political and cost issues surrounding the transportation of ²³⁸Pu and ²³⁹Pu and other transuranic (TRU) bearing waste items for consolidation and disposal. Significant inventories of these materials exist at commercial research and development facilities, Nuclear Regulatory Commission (NRC) licensed fuel cycle facilities and Department of Energy (DOE) sites. These materials are designated for ultimate disposal at the DOE’s Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM. The transportation of these materials is a national issue requiring utilization of all tools available to accomplish the mission at hand.

When these isotopes mentioned previously are present in concentrations above the values specified in Title 49 U.S. Code of Federal Regulations (CFR) Part 173.435¹ , use of an approved Type B package is required. Packages used for plutonium shipments must also meet the special requirements specified in Title 10 U.S. Code of Federal Regulations (CFR) Part 71.63, Special Requirements for Plutonium Shipments.²

The currently available packaging options for Type B transportation of plutonium are the TRUPACT-II, the Model 6400 Super Tiger and ATMX rail cars. Of these three options, the Super Tiger and TRUPACT - II are the only certified containers currently in active use. Nuclear Fuel Services maintains three Super Tiger. Two additional Super Tigers are owned and maintained by the DOE, an authorized user of the container. Among these, the Model 6400 Super Tiger is a uniquely capable tool for shipment of heat generating wastes, specifically ²³⁸Pu .

The Super Tiger is a currently certified Type B shipping container with a safe operational history of over twenty five years. The Nuclear Regulatory Commission, on July 7, 1997, renewed the Certificate of Compliance (COC)³ for the Super Tiger. There were no changes to the previous COC.

The Super Tiger Type B container is a protective overpack which provides thermal and impact resistance for its contents. The inner cavity is approximately 76" x 76" x 172" and is constructed of 3/16" thick mild steel. Closure of the container is by a ¼" thick aluminum plate with silicone rubber gasket . The inner cavity is centered and supported in an outer 3/16" metal jacket by approximately 10" of polyurethane foam at the end and approximately 10" on the sides. A hinged door section consisting of approximately 34" of foam encased in steel is bolted to the main outer steel jacket. The overall dimensions are the same as a standard Sealand container at 8’ x 8’ x 20’. The container’s main cavity is vented through a HEPA filter opening in the aluminum plate. The container has standard I.S.O. fittings at each corner. The total weight of the container when fully loaded is limited to 45,000 lbs.

Each Super Tiger can transport up to 16 standard 55 gallon drums of hard waste such as equipment, metal cans, tools, etc. or soft waste such as sheeting, gloves, paper, pre-filter media, polyethylene bottles, shoe covers, etc. The 55 gallon drums are packaged in foam overpacks and then placed and sealed in corrugated metal boxes, 8 per box. The Super Tiger accommodates two of these corrugated metal boxes for a total of 16 drums per shipment. The COC also specifies that large equipment items having a configuration which does not allow packaging in 55 gallon drums may be shipped inside the Super Tiger in plywood boxes configured as specified in the COC.

During the last five years, over 125 shipments of ²³⁸Pu and ²³⁹Pu waste has been shipped using the Super Tiger. One hundred four shipments of Pu glovebox D&D TRU waste was transported in 1994 from an NRC Category 1 licensee to the Y-12 facility in Oak Ridge, TN under NRC oversight. Twenty six shipments of Pu D&D TRU waste was shipped from Argonne National Laboratory - East to the Hanford Reservation in 1996. In March, 1997 the entire inventory of Pu bearing TRU materials at the Pantex facility was shipped to Los Alamos National Laboratory.

Each shipment using the Super Tiger may contain up to 200 grams of Pu in any isotopic composition for each shipment. This is the safe critical mass for Pu-239 and due to the fact that the COC is not isotope specific, it is also the limit for the non - fissile isotope ²³⁸Pu. Each drum may contain up to 60 grams of Pu regardless of isotopic composition so long as the total package limit is not exceeded. The large equipment items may contain up to 200 grams of Pu in any isotopic composition.

The wattage limit for each shipment is 235 Watts as determined in the Safety Analysis Report issued by Protective Packaging Inc. in August 1970⁴ . This is a less restrictive limit than the 200 gram limit, thus the 200 gram limit applies for both ²³⁸Pu and ²³⁹Pu. Other currently certified packages are limited to ²³⁸Pu inventories which are an order of magnitude lower. Table 1 lists the identification and maximum quantities of fissile constituents.

This waste category is meant for large metal items which do not easily lend themselves to packaging in 55 gallon drums. Following decontamination to remove smearable contamination above 150,000 dpm / 100 cm², remaining contamination is fixed. All sharp edges are dulled and pipe caps or blind flanges are installed where possible. Inner surfaces may be fixed with polyurethane foam. The waste is then packaged in plywood boxes constructed in accordance with the COC and the waste items are foamed in place using polyurethane foam.

This waste category is one of the most flexible of the content codes for the Super Tiger. The container may transport 60 grams of Pu per drum and 200 grams total per shipment. In many cases, Pu contaminated hard wastes such as equipment, metal cans, electrical equipment, piping or tools may be shipped without repackaging. In such cases, the outer 55 gallon drum is considered the decontaminated hard waste item. The outer drum which is typically clean, is treated with a fixative and then heat sealed inside two 55 gallon liners. The drum is then encased in a polyurethane foam block and fiber tape applied to hold the block together. Eight of these foam encased drums are then inserted into each of two corrugated metal containers which have been constructed according to drawings referenced in the COC. The corrugated metal boxes and foam blocks are reusable.

Soft waste items is waste such as sheeting, gloves, paper and shoe covers. Soft waste items are double bagged within 12 mil liners which are then individually heat sealed. The double bagged waste is then placed in a lined 55 gallon drum. The limit for plutonium under this waste category is 60 grams per drum and 200 grams per shipment. The drum is then encased in a polyurethane foam block and fiber tape applied to hold the block together. Eight of these foam encased drums are then inserted into each of two corrugated metal containers which have been constructed according to drawings referenced in the COC. The corrugated metal boxes and foam blocks are reusable.

The Super Tiger is unique among current Type B packages in that the package is easily handled at smaller facilities not having rigging or overhead crane capabilities. The list of items required for loading and unloading are:

1. Loading Dock (optional)
2. Fork Truck with extended forks (optional)
3. Straps for pulling inner containers from inner cavity of Super Tiger
4. Lifting straps for removing drums from inner containers
5. Miscellaneous Tools and Supplies (Foam Molds, Liners, Heat Sealer, Utility Knife, Lifting Strap, Duct Tape and Calibrated Torque Wrench) All of these items are typically provided by the contractor.

Facility staff can be trained on procedures and safety precautions in one 8 hour classroom session. A typical shipment of 16 drums can be loaded and manifested in one day using this container.

1. Title 49 U.S. Code of Federal Regulations (CFR) Part 173.435
2. Title 10 U.S. Code of Federal Regulations (CFR) Part 71.63, Special Requirements for Plutonium Shipments
3. Nuclear Regulatory Commission Certificate of Compliance for Radioactive Materials Packages, Certificate No. 6400, Revision 23 dated July 7, 1997.
4. Protective Packaging Inc. Safety Analysis Report for the Super Tiger dated August 28, 1970 as submitted to USAEC.

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