Glossary of Terms

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D

data collection cycle

time periods in which Member States are requested to submit information to the NEWMDB

Submissions of information are managed by way of a liaison between the NEWMDB Programme Officer and Country Co-ordinators. Initially, it is expected that Member States will be asked to submit information to the NEWMDB every two years, beginning in 2001. As experience is gained, Member States may be asked to submit information annually. Each request for a submission is a data collection cycle, which will have a start and end date.

deactivation of sodium

a waste treatment method to transform metallic sodium, which is highly reactive, into less chemically active forms

decommissioning

1. administrative and technical actions taken to allow the removal of some or all of the regulatory controls from a facility. This does not apply to a repository or to certain nuclear facilities used for mining and milling of radioactive materials, for which closure is used..

2. all steps leading to the release of a nuclear facility, other than a disposal facility, from regulatory control. These steps include the processes of decontamination and dismantling. [Joint Convention definition - not recommended for IAEA publications]

The use of the term decommissioning implies that no further use of the facility (or part thereof) for its existing purpose is foreseen.

The actions will need to be such as to ensure the long term protection of the public and the environment, and typically include reducing the levels of residual radionuclides in the materials and the site of the facility so that the materials can be safely recycled, reused or disposed of as exempt waste or as radioactive waste, and the site can be released for unrestricted use or otherwise reused.

Decommissioning typically includes dismantling the facility (or part thereof), but in the Agency’s usage this need not be the case. It could, for example, be decommissioned without dismantling and the existing structures subsequently put to another use (after decontamination).

decontamination

the complete or partial removal of contamination by a deliberate physical, chemical or biological process.

This definition is intended to include a wide range of processes, but to exclude the removal of radionuclides from within the human body, which is not considered to be decontamination.

dedicated

used in the original NEWMDB (no longer used) to indicate a facility for managing sealed radioactive sources (SRS) within the following scope:

(1) encompasses all SRS, not just disused or spent SRS

(2) the only wastes processed, stored or disposed by the facility are disused and/or spent SRS declared to be waste or the facility has a programme to track the location and characteristics of all SRS in the facility

The intent of the definition is to help ensure that Member States can report the inventory of SRS at waste management sites, which may be difficult or impossible to do for facilities at sites in which not all SRS are tracked individually.

defense (defence)

see defense/military

defense/military

defense/military, defense (defence), and military are terms used in the NEWMDB to describe radioactive wastes derived from non-civilian applications of radioactive materials

depleted uranium

uranium containing a lesser mass percentage of uranium-235 than in natural uranium

designate

A Country Co-ordinator can designate someone to do most of the data entry and/or interactions with the NEWMDB Programme Officer.

designate e-mail

A Country Co-ordinator can specify whether or not NEWMDB system messages are copied to or forwarded to his/her designate.

discharge

1. planned and controlled release of (usually gaseous or liquid) radioactive material to the environment.

2. a planned and controlled release into the environment, as a legitimate practice, within limits authorized by the regulatory body, of liquid or gaseous radioactive materials that originate from regulated nuclear facilities during normal operation. [Joint Convention definition - not recommended for IAEA publications]

disposal

1. emplacement of waste in an appropriate facility without the intention of retrieval.

2. the emplacement of spent fuel or radioactive waste in an appropriate facility without the intention of retrieval. [Joint Convention definition - not recommended for IAEA publications]

Some countries use the term disposal to include discharges of effluents to the environment. In some States, the term disposal is used administratively in such a way as to include, for example, incineration of waste or the transfer of waste between operators. In Agency publications, disposal should only be used in accordance with the more restrictive definition given above.The term disposal implies that retrieval is not intended; it does not mean that retrieval is not possible.

disposal facility

synonymous with repository

disposed

see disposal

disposition

used in the NEWMDB to indicate a waste management related destination for waste - for example, waste can be routed to a facility for processing, storage or disposal

disposition option

used in the NEWMDB to indicate option(s) for routing waste to a waste management facility, as follows:

origin => destination(s)
generator => processing, storage, disposal
processing => storage, disposal
storage => processing, disposal

disused

used in the NEWMDB to indicate a sealed radioactive source (SRS) that is no longer in use or intended to be used

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