ISO/FDIS 20305

ISO/TC 82/SC 7
Secretariat: KATS
Date: 2025-12-172026-xx
Mine closure and reclamation — Vocabulary
Fermeture et remise en état des mines — Vocabulaire
FDIS stage
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying
and microfilm, or posting on the internet or an intranet, without prior written permission in writing. Permission can be
requested from either ISO at the address below or ISO'sISO’s member body in the country of the requester.
ISO copyright office
Case postale 56 • CP 401 • Ch. de Blandonnet 8
CH-12111214 Vernier, Geneva 20
Tel.Phone: + 41 22 749 01 11
Fax + 41 22 734 10 79
E-mail : copyright@iso.org
WebWebsite: www.iso.chorg
Field Code Changed
PrintedPublished in Switzerland

ii
Contents Page
Foreword . iv
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Terms related to the phase during which mine closure processes are undertaken (see
Figure A.1) . 1
3.2 Terms related to the process of mine closure (see Figure A.2) . 2
3.3 Terms related to the status of mine closure (see Figure A.3) . 3
3.4 Terms related to the management of mine closure (see Figure A.4) . 4
3.5 Terms related to legal and other obligations (see Figure A.5) . 4
3.6 Terms related to the use of land associated with mining and mine closure (see
Figure A.6) . 5
3.7 Terms related to mine closure outcomes (see Figure A.7) . 6
3.8 Terms related to mine features (see Figure A.8) . 6
3.9 Terms related to mined materials (see Figure A.10) . 8
3.10 Terms related to the management and assessment of mine closure risk (see Figure A.10)9
3.11 Terms related to the specific mine closure risks (see Figure A.11) . 10
3.12 Terms related to treatments used in mine closure to address risk (see Figure A.12) . 10
3.13 Terms related to mine closure cost (see Figure A.13) . 12
Annex A (informative) Relationship between terms . 15
Bibliography . 21
Index . 22

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO [had/had not] received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that this
may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 82, Mining, Subcommittee SC 7, Sustainable
mining and mine closure.
This second edition cancels and replaces the first edition (ISO 20305:2020), which has been technically
revised.
The main changes are as follows:
— — inclusion of concept diagrams within Annex AAppendix A;
— — inclusion of thematic headings;
— — inclusion of concepts relevant to ISO21975:2021ISO/TS 21975 and ISO24419:2024ISO 24419
(series);
— — major revision of concept system for mine closure processes;
— — minor revisions of all concept systems and definitions to improve alignment with ISO terminological
requirements;
— — improved harmonisation of definitions;
— — removal of mine closure activity concept system and general language terms not considered unique to
subject field;
— — refraining of mine closure strategy concept system as mine closure process concept system.
iv
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
v
Introduction
This vocabulary has been prepared to support the application of concepts presented within mine closure and
reclamation standards , as well as to facilitate effective communication within the subject field of mine closure
and reclamation.
Identified concepts were assessed and filtered based on the following criteria:
— — the concept is used within, and considered critical to, ISO mine closure and reclamation standards or
documentation either existing or being prepared;
— — the concept is sufficiently important to avoid misunderstanding or ambiguity, such as where an
alternative or conflicting definition exists or is in common use;
— — the concept is required to achieve a common understanding within the field of mine closure and
reclamation, including amongst non-experts.
In selecting concepts for inclusion within this standard every effort has been made to avoid:
— — general concepts used across, and common to, subject fields other than mine closure and reclamation;
— — use of a single term for multiple concepts or multiple terms for a single concept;
— — contradictions occurring in terminological entries in other standards prepared under TC 82.
Where a concept was identified within the ISO Online Browsing Platform the definition was reviewed and
adopted, if applicable in the mine closure and reclamation context. Definitions presented in publicly available
and relevant documents were also reviewed and included where appropriate.
Where concepts have been defined within a specific mine closure and reclamation standard or jurisdictional
statute that definition will supersede any term or definition presented within this standarddocument.
Concepts on mine closure and reclamation management have been classified into the following thematic
headings:
— — mine closure phase;
— — mine closure process;
— — mine status;
— — mine closure governance;
— — legal and other obligations;
— — land use;
— — mine closure outcome;
— — mine feature;
— — mine material;
— — mine closure risk;
vi
— — mine closure treatment;
— — mine closure cost.
This document is not intended to present a comprehensive list of all terms or concepts utilized within mine
closure and reclamation.
vii
Mine closure and reclamation — Vocabulary
1 Scope
This document establishes a vocabulary for mine closure and reclamation management.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminologicalterminology databases for use in standardization at the following
addresses:
— — ISO Online browsing platform: available at https://www.iso.org/obp
— — IEC Electropedia: available at https://www.electropedia.org/
3.1 Terms related to the phase during which mine closure processes are undertaken (see
Figure A.1)
3.1.1 3.1.1
life of mine
phase when a mine is, or is planned to be, in production
Note 1 to entry: Based on a mine plan developed in consideration of the available capital and ore reserves, or a
reasonable and justifiable extension of the reserve estimate.
[3 ]
[SOURCE: ICMM 2019 : , modified — Note 1 to entry has been added.]
3.1.1.1 3.1.1.1
pre-closure
part of life of mine (3.1.1(3.1.1),), during which mine closure (3.2.1(3.2.1)) is planning to progressively develop
the scope of closure (3.1.1.2(3.1.1.2))
Note 1 to entry: Pre-closure can include development, operation, and care and maintenance (3.1.1.1.1(3.1.1.1.1))
phases.
3.1.1.1.1 3.1.1.1.1
care and maintenance
temporary mine closure
part of pre-closure (3.1.1.1(3.1.1.1)) when a mine or mine facility (3.8.1.1(3.8.1.1)) is suspended
(3.3.1.4(3.3.1.4),), and is maintained in anticipation of production recommencing
Note 1 to entry: Care and maintenance can also refer, in some jurisdictions, to the post closure (3.1.1.3(3.1.1.3)) phase.
3.1.1.2 3.1.1.2
closure
part of life of mine (3.1.1(3.1.1)) when a mine or mine feature (3.8.1(3.8.1)) is closed (3.3.1.2(3.3.1.2)) and
during which the mine closure plan (3.2.1.5(3.2.1.5)) is executed
Note 1 to entry: Closure can be referred to as active closure in combination with post-closure (3.1.1.3(3.1.1.3).).
3.1.1.3 3.1.1.3
post closure
part of life of mine (3.1.1(3.1.1),), when monitoring and maintenance and other relevant management activities
are undertaken
Note 1 to entry: Post closure includes active maintenance and monitoring undertaken to assess and maintain the
performance of mine closure treatment (3.12.1(3.12.1).).
Note 2 to entry: Post closure can be referred to as active closure in combination with closure (3.1.1.2(3.1.1.2).).
3.1.1.4 3.1.1.4
completion
part of life of mine (3.1.1(3.1.1),), when relinquishment (3.2.1.6(3.2.1.6)) occurs
Note 1 to entry: Completion can be referred to as passive closure.
3.2 Terms related to the process of mine closure (see Figure A.2)
3.2.1 3.2.1
mine closure
process to plan and implement strategies to carry out the related activities associated with the cessation of
mining and to achieve relinquishment (3.2.1.6(3.2.1.6)) and transition to the post mining land use
(3.6.1.1(3.6.1.1))
Note 1 to entry: Mine closure can be implemented progressively for specific features within a mine site or operation.
3.2.1.1 3.2.1.1
mine closure design
part of mine closure (3.2.1(3.2.1)) for design of closure (3.1.1.2(3.1.1.2)) of a specific mine feature (3.8.1(3.8.1),
),domain (3.8.2(3.8.2)) or other aspect (3.10.1(3.10.1))
3.2.1.2 3.2.1.2
decommissioning
part of mine closure (3.2.1(3.2.1)) for the safe de-activation, removal and disposal of a redundant mine facility
(3.8.1.1(3.8.1.1))
3.2.1.3 3.2.1.3
mitigation
part of mine closure (3.2.1(3.2.1)) bearing on the management of the adverse effects of mining
3.2.1.3.1 3.2.1.3.1
remediation
mitigation (3.2.1.3(3.2.1.3)) removing, reducing or neutralizing hazardous material, or other not-desired
substances
Note 1 to entry: Post-mining hazards can include soil and water contamination, unstable ground, gas emission or similar
events which impact the environment.
Note 2 to entry: Remediation is often the first step in reclamation (3.2.1.3.2(3.2.1.3.2)) and is conducted in parallel or
immediately after decommissioning (3.2.1.2(3.2.1.2).).
3.2.1.3.2 3.2.1.3.2
reclamation
mitigation (3.2.1.3(3.2.1.3)) recovering disturbed land to safe, stable, non-polluting state
Note 1 to entry: Reclamation can also be referred to as alleviation.
3.2.1.3.2.1 3.2.1.3.2.1
restoration
reclamation (3.2.1.3.2(3.2.1.3.2)) of a mine feature (3.8.1(3.8.1),), domain (3.8.2(3.8.2)) or other area disturbed
by mining to a sustainable condition corresponding with its natural or reference state
3.2.1.3.3 3.2.1.3.3
rehabilitation
outcome of reclamation (3.2.1.3.2(3.2.1.3.2))
3.2.1.4 3.2.1.4
repurposing
redevelopment
part of mine closure (3.2.1(3.2.1)) converting a mine feature (3.8.1(3.8.1),), domain (3.8.2(3.8.2)) of other area
disturbed by mining to a productive condition
3.2.1.5 3.2.1.5
mine closure plan
part of mine closure (3.2.1(3.2.1)) comprising documented information
3.2.1.6 3.2.1.6
relinquishment
part of mine closure (3.2.1(3.2.1)) verifying that completion criteria (3.7.2.2(3.7.2.2)) have been met and
closureliability (3.13.2closure liability (3.13.2)) and ownership of the mine or mine feature (3.8.1(3.8.1)) have
been transferred to the government or a third party
3.2.2 3.2.2
transition
planned change of an aspect (3.10.1(3.10.1)) of mine closure (3.2.1(3.2.1)) from its operational state to the
intended closure status (3.3.1(3.3.1))
Note 1 to entry: Transition can include environmental, social and economic aspects of mine closure.
3.3 Terms related to the status of mine closure (see Figure A.3)
3.3.1 3.3.1
closure status
status of a mine or mine feature (3.8.1(3.8.1)) with respect to the closure phase
3.3.1.1 3.3.1.1
abandoned
status of a mine or mine feature (3.8.1(3.8.1)) having not been formally relinquished (3.3.1.5(3.3.1.5)) and for
which the responsibility for mine closure (3.2.1(3.2.1)) cannot be allocated to an individual or organization
Note 1 to entry: Closure liability (3.13.2(3.13.2)) can fall to the landowner if freehold land.
Note 2 to entry: Abandoned can also be referred to as a “derelict”, “orphaned” or “legacy mine”.
3.3.1.2 3.3.1.2
closed
status of a mine or mine feature (3.8.1(3.8.1)) for which mining has ceased and for which the mine owner or
operator is implementing, or has yet to commence implementation of, mine closure (3.2.1(3.2.1))
3.3.1.3 3.3.1.3
reclaimed
status of a mine or mine feature (3.8.1(3.8.1)) for which mine closure (3.2.1(3.2.1)) has been implemented, and
the post closure (3.1.1.3(3.1.1.3)) phase has commenced
3.3.1.4 3.3.1.4
suspended
status of a mine or mine feature (3.8.1(3.8.1)) for which mining, or processing, has temporarily ceased and
operations have been placed in care and maintenance (3.1.1.1.1(3.1.1.1.1))
3.3.1.5 3.3.1.5
relinquished
status of a mine or mine feature (3.8.1(3.8.1)) for which relinquishment (3.2.1.6(3.2.1.6)) has been completed
3.4 Terms related to the management of mine closure (see Figure A.4)
3.4.1 3.4.1
interested party
stakeholder
person, group or organization with the potential to affect, or be affected by mine closure (3.2.1(3.2.1))
3.4.2 3.4.2
stewardship
care, maintenance, and management of mined land after mine closure (3.2.1(3.2.1)) ensuring ongoing
management of risk (3.10.3(3.10.3))
Note 1 to entry: Stewardship includes surveillance, aftercare, monitoring and maintenance for a mining legacy
(3.10.2.1(3.10.2.1)) and sites subject to regulation.
Note 2 to entry: Stewardship may not be associated with institutional control (3.4.3(3.4.3).).
3.4.3 3.4.3
institutional control
legal or administrative action, or requirement, imposed on non-operational mined land
Note 1 to entry: Institutional control aims to protect and maintain mitigation (3.2.1.3(3.2.1.3)) works and minimize
human exposure to harm while protecting values and particular ongoing uses.
Note 2 to entry: Institutional control can include deeds, land use zoning, security and monitoring.
Note 3 to entry: Institutional control can also be referred to as ”surveillance”.
3.5 Terms related to legal and other obligations (see Figure A.5.)
3.5.1 3.5.1
obliging event
event generating a present obligation (3.5.2(3.5.2))
3.5.2 3.5.2
present obligation
obligation resulting in an entity having no realistic alternative to settling the obligation
3.5.2.1 3.5.2.1
legal obligation
present obligation (3.5.2(3.5.2)) derived from the application of law
3.5.2.2 3.5.2.2
constructive obligation
present obligation (3.5.2(3.5.2)) derived from an organization’s actions or stated commitment
Note 1 to entry: Constructive obligation is established when an organization has created a valid expectation that it will
accept responsibility.
Note 2 to entry: Constructive obligation can be established by a pattern of past practice, published policies or a
sufficiently specific current statement.
Note 3 to entry: Constructive obligation is often established through stakeholder (3.4.1(3.4.1)) engagement.
3.5.2.2.1 3.5.2.2.1
cultural obligation
constructive obligation (3.5.2.2(3.5.2.2)) founded in the customs, traditions and values of a particular culture
or community
Note 1 to entry: Cultural obligation is generally based on moral, ethical, and social principles rather than legal statutes
or contractual agreements.
Note 2 to entry: Cultural obligation is often upheld through community norms and shared values.
3.5.2.2.2 3.5.2.2.2
social obligation
constructive obligation (3.5.2.2(3.5.2.2)) founded in behaviour, relationships and values within broad societal
context
3.6 Terms related to the use of land associated with mining and mine closure (see
Figure A.6)
3.6.1 3.6.1
land use
human use or management of land within a relevant boundary
Note 1 to entry: Land use is, generally, for the purpose of habitation, production, recreation or conservation.
Note 2 to entry: Land use can be classed as wilderness or natural environment.
Note 3 to entry: Land use can occur concurrently with mining.
3.6.1.1 3.6.1.1
pre-mining land use
part of land use (3.6.1(3.6.1)) prior to the commencement of mining
3.6.1.2 3.6.1.2
post closure land use
part of land use (3.6.1(3.6.1)) following completion (3.1.1.4(3.1.1.4))
3.6.2 3.6.2
land capability
ability of land to support a given post closure landclosureland use (3.6.1.2(3.6.1.2),), based on an evaluation of
the physical, chemical and biological characteristics
3.6.3 3.6.3
land suitability
ability of land to support a given post closure land use (3.6.1.2(3.6.1.2),), based on an evaluation of the land
capability (3.6.2(3.6.2),), as well as social, economic and cultural characteristics
Note 1 to entry: Land suitability can be interchangeable with land capability (3.6.2(3.6.2)) is some jurisdictions.
3.6.4 3.6.4
offset
measurable compensation for the loss of, or reduction in post-closure land suitability (3.6.3(3.6.3))
Note 1 to entry: An offset remains due to impact (3.10.2(3.10.2)) or residual risk (3.10.3.2(3.10.3.2)) after appropriate
prevention and mitigation (3.2.1.3(3.2.1.3)) has been taken.
Note 2 to entry: An offset can be applied where a specified post closure land use (3.6.1.2(3.6.1.2)) cannot be achieved
due to post mining land capability (3.6.2(3.6.2)) or land suitability (3.6.3(3.6.3)).
Note 3 to entry: Offsets can last in perpetuity or for as long as the impact or residual risk exists.
Note 4 to entry: An offset can include mitigation of a mining legacy (3.10.2.1(3.10.2.1)) in some jurisdictions.
Note 5 to entry: An offset can still be required even if a previous offset was established as part of mining approvals.
3.7 Terms related to mine closure outcom
...