See the letter from P. H. Lohaus to Commission Licensees dated January 24, 1991. Included with is the extensive document, “Waste Form Technical Position, Revision 1”, which must be reviewed in its entirety for proper interpretation. The document was written in the context of 10 CFR 20.311, but it also applies to the “new” 10 CFR Part 20, Section 20.2006 and Appendix F to 20.1001-20.2401. HPPOS-289 and HPPOS-291 contain related topics.
The regulation “Licensing Requirements for Land Disposal of Radioactive Waste,” 10 CFR Part 61, establishes a waste classification system based on the radionuclide concentrations in the wastes. Class B and C waste are required to be stabilized. Class A wastes have lower concentrations and may be segregated without stabilization. Class A wastes may also be stabilized and disposed of with class B and C wastes. All Class A liquid wastes, however, require solidification or absorption to meet the free liquid requirements. Structural stability is intended to ensure that the waste does not degrade and (a) promote slumping, collapse, or other failure of the cap or cover over a near-surface disposal unit and thereby lead to water infiltration, or (b) impart a substantial increase in surface area of the waste form that could lead to an increase in leach rate. Stability is also a factor in limiting exposure to an inadvertent intruder since it provides greater assurance that the waste form will be recognizable and nondispersable during its hazardous lifetime. Structural stability of a waste form can be provided by the waste form itself (as with activated stainless steel components), by processing the waste to a stable form (e.g., solidification), or by emplacing the waste in a container or structure that provides stability (e.g., high integrity container or engineered structure).
This technical position on waste form was initially developed in 1983 to provide guidance to both fuel-cycle and non-fuel-cycle waste generators on waste form test methods and results acceptable to the NRC staff for implementing the 10 CFR Part 61 waste form requirements. It has been used as an acceptable approach for demonstrating compliance with the 10 CFR Part 61 waste stability criteria. This position includes guidance on (1) the processing of wastes into an acceptable, stable waste form, (2) the design of acceptable high integrity containers, (3) the packaging of filter cartridges, and (4) minimization of radiation effects on organic ion-exchange resins. The regulation, 10 CFR 20.311 (d) (1) [or, at present, 10 CFR 20.2006 (d) and Section III.A.1 of Appendix F to ••20.2001-2401], requires waste generators and processors to prepare wastes that meet the waste characteristics requirements of Part 61 (including the requirements for structural stability). The recommendations and guidance provided in this technical position are an acceptable method to demonstrate waste stability. One way of demonstrating conformance with the general recommendations contained in this technical position is to reference an approved Topical Report, because such reports are reviewed and approved by the acceptance criteria contained in this technical position. However, additional actions (e.g., plant-specific process control procedures) by waste generators will be needed to demonstrate that a stabilized plant-specific waste stream satisfies Part 61 waste form requirements.
Since the initial issuance of the Technical Position, it has been the intent of the NRC staff to provide additional guidance on waste form as it became necessary to address other pertinent waste form issues. One such issue involves the use of cement to stabilize low level wastes. Field experience and laboratory testing of cement solidified low-level radioactive waste has shown that some unique chemical and physical interactions can occur between the cement constituents and the chemicals and compounds that can exist in the waste materials. Therefore, an appendix (Appendix “A”) dealing with the qualification testing, performance confirmation and reporting of mishaps involving cement-stabilized waste forms has been included in this revision to the Technical Position.
To provide more comprehensive guidance and cement stabilization of low-level radioactive waste, Appendix A addressed several areas of concern that were not considered in the May 1983, version of this Technical Position. Thus, information and guidance on cement waste form specimen preparation, statistical sampling and analysis, waste characterization, process control program (PCP) specimen preparation and examination, surveillance specimens and reporting of mishaps are provided in Appendix A. The guidance provided in Appendix A is the culmination of an extended period of study and information gathering and exchange between NRC staff and representatives of various organizations, including government laboratories, the Advisory Committee on Nuclear Waste (ACNW), cement processing vendors, other waste form vendors, nuclear utilities, and state regulatory agencies. Especially useful in the development of the guidance in Appendix A was the information exchanged in the Workshop on Cement Stabilization of Low-Level Radioactive Waste held in June, 1989. The workshop proceedings have been published as an NRC report, NUREG / CP-0103, which is available from either the Superintendent of Documents, U.S. Government Printing Office, P.O. Box 37082, Washington, D.C. 20013-7082, or National Technical Information Service, Springfield, Virginia 22161.
Regulatory References: 10 CFR 20.311, 10 CFR 20.2006, 10 CFR 61.55, 10 CFR 61.56
Subject codes: 9.0
Applicability: All