Mine Closure and Post-Mining Management

164 Pages·11.073 MB·English

MINE CLOSURE AND POST-MINING MANAGEMENT
INTERNATIONAL STATE-OF-THE-ART

INTERNATIONAL COMMISSION ON MINE CLOSURE
INTERNATIONAL SOCIETY FOR ROCK MECHANICS

June 2008

MINE CLOSURE AND POST-MINING MANAGEMENT
INTERNATIONAL STATE-OF-THE-ART

INTERNATIONAL COMMISSION ON MINE CLOSURE
INTERNATIONAL SOCIETY FOR ROCK MECHANICS

June 2008

Preliminary remark

The elaboration of the present report by the ISRM mine closure commission has
necessitated a significant work. In addition to the technical work, photos, figures
and references have been collected from different countries and sources.
Despite the effort made, some of the included illustrations or references may
appear to be unclear, wrong or uncompleted. In case of such a detection, the
authors previously thank all readers to let them be aware of any improvement and
suggestion, especially with respect to copyright issues. The document will be
improved as soon as possible by taking into account corrections and suggestions.
Morever, the present document concludes the first step of the commission work
that can be completed and ameliorated. Any further contribution will thus be
welcome (e.g. complementary references, technical modifications). They will be
considered by the commission in a further edition of the document.
The authors warmly thank the readers for sending them their opinion expression
and advice that would be essential in improving the quality of the commission
work.
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Christophe DIDIER
Deputy Director Prof. Nielen van der Merwe
Ground and Underground Division Technical Director
INERIS - France Bon-Terra Mining (Pty) Ltd

[email protected] [email protected]

Dr. Marc Betournay Dr.-Ing. Mark Mainz
Senior Scientist Geotechnical Engineer
CANMET- Canada IHS - Germ any
[email protected] [email protected]

Dr. Andrej KOTYRBA Dr. Ömer Aydan
Head of Geophysics Laboratory Senior Scientist
Central Mining Institute - Poland. Tokaï University – Japan
[email protected] [email protected]

Dr. Jean-Pierre JOSIEN Dr. Won-Kyong SONG
Director Chief of Mining & Safety Group
GEODERIS- France KIGAM - Korea
[email protected] [email protected]

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Taking part in the mine closure commission has been a wonderful experience.
I would like to warmly thank each member for his generous and precious involvement
in the commission process, from a technical but also and probably above all, from a
human point of view.
It has been a real pleasure to work together during the last two years, to learn from
each other and to contribute to a common work.
The friendship initiated between the members will, certainly, survive beyond the
commission mandate. So will our desire to continue and consolidate our technical
exchanges.
Together with others members of this commission, I sincerely hope that the present
report will be helpful and of interest for the community involved in mining, post-
mining and connected areas.

Christophe DIDIER
President of the Mine Closure Commission
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CONTENTS
CONTENTS ............................................................................................................................................................................... 7
1 INTRODUCTION AND OBJECTIVES ........................................................................................................................ 9
1.1 COMMISSION CONSTITUTION .......................................................................................................................................... 9
1.2 ORGANISATION OF THE COMMISSION’S WORK .............................................................................................................. 10
1.3 GUIDELINES OUTLINE ................................................................................................................................................... 10
2 BRIEF OVERVIEW OF THE INTERNATIONAL POST MINING CONTEXT ................................................... 13
2.1 INTERNATIONAL MINING EVOLUTION ........................................................................................................................... 13
2.1.1 Very old mining activities .................................................................................................................................. 13
2.1.2 Industrial development period and present situation ......................................................................................... 14
Countries whose mining industry is nowadays almost dormant...................................................................................................... 14
Countries whose mining industry has been affected by recent decline ........................................................................................... 15
Countries that remain with a strong mining industry ...................................................................................................................... 19
2.2 POTENTIAL HAZARDS AND HARMFUL EFFECTS DURING POST-MINING PERIOD ........................................................... 20
2.2.1 Flooding or disturbance of rivers’ flow ............................................................................................................. 21
2.2.2 Surface instabilities ............................................................................................................................................ 21
2.2.3 Mine gas emission on surface ............................................................................................................................ 22
2.2.4 Ground and water pollution, emission of ionising radiation ............................................................................. 22
2.3 NATIONAL POST-MINING MANAGEMENT POLICIES ..................................................................................................... 23
2.4 REFERENCES ................................................................................................................................................................ 26
3 MINING METHODS ..................................................................................................................................................... 29
3.1 VERY OLD MINING METHODS ........................................................................................................................................ 29
3.2 ROOM-AND-PILLAR MINING .......................................................................................................................................... 30
3.3 SUB-LEVEL STOPING OR BLASTHOLE STOPING .............................................................................................................. 31
3.4 SHRINKAGE STOPING .................................................................................................................................................... 32
3.5 CUT-AND-FILL MINING ................................................................................................................................................. 33
3.6 LONGWALL MINING ..................................................................................................................................................... 33
3.7 SUB-LEVEL CAVING ...................................................................................................................................................... 35
3.8 BLOCK CAVING ............................................................................................................................................................ 36
3.9 REFERENCES ................................................................................................................................................................ 37
4 NATURE OF GEOMECHANICAL HAZARDS ........................................................................................................ 39
4.1 GROUND MOVEMENTS ABOVE UNDERGROUND MINES .................................................................................................. 39
4.1.1 Continuous movements ...................................................................................................................................... 39
Subsidence or heave ........................................................................................................................................................................ 39
4.1.2 Discontinuous movements .................................................................................................................................. 44
Sinkholes......................................................................................................................................................................................... 44
Discontinuous subsidence ............................................................................................................................................................... 55
4.1.3 Induced seismicity .............................................................................................................................................. 59
4.2 SLOPE INSTABILITIES ................................................................................................................................................... 61
4.2.1 Rock falls ............................................................................................................................................................ 61
4.2.2 Slides or slope movement ................................................................................................................................... 62
4.2.3 Flow slides ......................................................................................................................................................... 65
4.3 REFERENCES ................................................................................................................................................................ 67
5 HAZARD ASSESSMENT METHODS ........................................................................................................................ 71
5.1 DEFINITIONS ................................................................................................................................................................. 71
5.2 HAZARD ASSESSMENT SPECIFICALLY TO THE POST MINING CONTEXT ........................................................................ 72
5.3 SELECTION OF BEST ADAPTED HAZARD ASSESSMENT METHODS ................................................................................. 73
5.3.1 Main parameters influencing the selection ........................................................................................................ 73
5.3.2 Hazard assessment methods adapted to non-sensitive cases ............................................................................. 76
5.3.3 Hazard assessment methods adapted to semi-sensitive cases ............................................................................ 76
5.3.4 Hazard assessment methods adapted to sensitive cases .................................................................................... 78
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5.4 PRINCIPAL STAGES OF A HAZARD ASSESSMENT PROCESS .............................................................................................. 79
5.4.1 Desk Study .......................................................................................................................................................... 79
5.4.2 Field Study ......................................................................................................................................................... 81
5.4.3 Complementary field investigation stage ........................................................................................................... 81
5.4.4 Main applications of geophysical methods ........................................................................................................ 82
5.5 MAJOR FACTORS INFLUENCING HAZARD PREDISPOSITION ............................................................................................ 85
5.5.1 Influence of time ................................................................................................................................................. 85
5.5.2 Influence of water .............................................................................................................................................. 86
5.5.3 Influence of geology and mining methods .......................................................................................................... 88
Geology........................................................................................................................................................................................... 88
Mining Methods .............................................................................................................................................................................. 91
5.6 HAZARD MAPPING ....................................................................................................................................................... 94
5.7 REFERENCES ................................................................................................................................................................ 95
6 HAZARD MANAGEMENT METHODS .................................................................................................................... 97
6.1 TREATMENT ................................................................................................................................................................. 97
6.1.1 Backfilling .......................................................................................................................................................... 97
6.1.2 Geosynthetics ................................................................................................................................................... 101
Reinforced Concrete Slabs ............................................................................................................................................................ 104
Shaft filling stabilisation ............................................................................................................................................................... 106
6.2 LAND USE MANAGEMENT .......................................................................................................................................... 108
6.2.1 Preventive regulation and mapping ................................................................................................................. 108
6.2.2 Damage Compensation and Preventive Evacuation ........................................................................................ 110
6.3 MONITORING .............................................................................................................................................................. 111
6.3.1 Ground Movements Monitoring ....................................................................................................................... 111
Indirect Techniques ....................................................................................................................................................................... 116
6.3.2 Monitoring mine-induced seismicity to identify potential instability sources .................................................. 118
6.3.3 Monitoring of abandoned mines located in areas sensitive to earthquakes ..................................................... 119
6.3.4 Time Domain Reflectometry Monitoring for Abandoned Mines ...................................................................... 120
6.3.5 Monitoring techniques under scientific and experimental development .......................................................... 123
6.4 DATABASE MANAGEMENT .......................................................................................................................................... 124
6.4.1 Importance of data management ...................................................................................................................... 124
6.4.2 Example of abandoned coal mines database using GIS in Korea .................................................................... 125
6.5 REFERENCES .............................................................................................................................................................. 129
7 RECOMMENDED ADDITIONAL READING ........................................................................................................ 133

LIST OF APPENDICES ……………………………………………………………………………………………………141

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