the name, WAC describe requirements that are placed on received waste in order that it can be accepted at a facility. Wastes delivered to any disposal site are required to meet LDR and any conditions imposed by the WAC or the facility permitting process. The criteria may address shipping requirements; containerization; physical, nuclear, and chemical properties, including gas generation; and waste characterization. Each facility develops specific WAC to ensure that it operates safely and will meet all applicable regulations during operation and after closure. For non-DOE facilities, such criteria may be incorporated in the facility permit or specified separately. In the case of treatment facilities, the WAC do not establish requirements on the waste form for disposal but rather on the waste as received in anticipation of further treatment prior to disposal. WAC are site specific, and may place additional constraints on the selection of waste forms for disposal.

Except for the Envirocare of Utah facility, no commercial options are available for the land disposal of DOE mixed waste. At Envirocare, the WAC place low limits on the radioactivity of waste that can be received, thereby restricting the use of this site. Although the DOE sites at Hanford and the Nevada Test Site can dispose of mixed wastes generated on-site, they are not currently available for mixed waste generated at other sites. The WIPP project may accept waste meeting the definition of TRU and MTRU waste, but it may not receive MLLW. Since disposal sites are not available for the majority of MLLW, DOE is faced with having to design treatment systems and subsequent waste forms without knowledge of potential constraints that may be imposed in the future. Waste treatment and temporary storage of the waste forms until a disposal facility is available may be necessary to meet EM's cleanup schedule. However, this expedient is more uncertain and expensive compared with treatment followed immediately by final disposal, and imposes an additional set of regulations applicable to temporary storage facilities.

Shipping regulations imposed by DOT may add constraints with regard to packaging of waste material for transport if wastes must be shipped to an off-site location for treatment or disposal. A description of the effect of WAC and transportation requirements on TRU waste forms for the WIPP facility is given in Box 2.