CH-TRAMPAC - Waste Isolation Pilot Plant - U.S. Department of ...

CH-TRAMPAC Document Rev. 2, May 20052.5.1 Requirements2.5 Filter VentsEach payload container to be transported in the TRUPACT-II or HalfPACT, including allpayload containers that are overpacked in other payload containers, shall have one or more filtervents or equivalent venting mechanisms. Payload container filter vents must meet the minimumspecifications of Table 2.5-1 and this section. Any equivalent venting mechanisms shall meetthe minimum total hydrogen diffusivity per container specified in Table 2.5-1. Specifications forfilter vents in plastic bags and other inner layers used as confinement layers within payloadcontainers are also included in Table 2.5-1.The use of a heat-sealed filtered bag as the innermost layer of confinement to package CH-TRUwaste is limited to Waste Material Types I.3, II.1, III.1, and III.3 provided that there is nopotential for contact of the filters with water. Waste Material Types II.3 and III.2, which bydefinition include a metal can as the innermost layer of confinement, may use heat-sealed filteredbags as confinement layers outside of the innermost metal can. Because Waste MaterialType II.2 (inorganic solids packaged in metal cans) does not generate flammable gas, heat-sealedfiltered or unfiltered bags may be used as confinement layers outside of the innermost metal can.For other waste material types, heat-sealed filtered bags are not allowed as the innermost layer ofconfinement.The use of filtered bags in waste packaging configurations must be specified in approved contentcodes. Appendix 3.11 of the CH-TRU Payload Appendices 1 describes the use of filtered bags asconfinement layers and the basis for the increased decay heat limits for specific shippingcategories using filtered bags.Filter vents for the outer payload container and any overpacked payload container shall belegibly marked to ensure both (1) identification of the supplier and (2) date of manufacture, lotnumber, or unique serial number.The filter vent housing and element for the outer payload container shall have an operatingtemperature range from –40 degrees Celsius (°C) to +70°C (-40 degrees Fahrenheit [°F] to+158°F). The filter vent threads shall be compatible with the bung in the container or shall beself-tapping.1 U.S. Department of Energy (DOE), CH-TRU Payload Appendices, U.S. Department of Energy, Carlsbad FieldOffice, Carlsbad, New Mexico.2.5-1