Publication Name

MINING FOR CLOSURE

This section is intended to provide more back-

ground in three key areas. Firstly, the reasons for

mine closure are addressed and these underlying

reasons are linked to possible outcome scenarios

– some far less desirable than others. Secondly,

the global problem of abandoned and orphaned

mine sites and the types of initiatives required to

deal with this problem are discussed. Thirdly, the

general form of stakeholder expectations regarding

mine closure is presented. These expectations are

then juxtaposed with closure requirements on the

one hand and emerging post-closure considera-

tions on the other.

4.1

New orebodies and mineral resources are con-

stantly being discovered through exploration but

the reserves contained in any particular deposit on

which a project is based are finite. All things being

equal, it is thus logical that all mining activities at

a certain mine site must come to a close at some

stage within a foreseeable future.

In much of the previous discussion, it has been in-

dicated that

the overall mine decommissioning process

should be integrated with the overall mine operation

planning process

. This appears in many instances

to bear with it an implicit assumption that mine

decommissioning usually occurs at a point in the

life of an operation where the economic recovery of

minerals has ceased

according to some plan

. Further,

that this cessation is an ordered outcome. If earlier

discussions of integrated mine planning hold, then

it is feasible that a mine can be designed and op-

erated with a continual focus on expected closure

outcomes and according to a well-known timetable.

As such, a process of progressive decommission-

ing should be undertaken.

This is of course feasible and some mines have

been designed operated and closed according to

predetermined plans. However, this has hardly

been the standard

modus operandi

of mining. His-

tory has shown that mining activity can cease for

many reasons and almost at any time. Many min-

ing legacies are much more than the result of mine

abandonment in the absence of legal and regulatory

frameworks to ensure adequate decommissioning

works.

In many instances they have been a part

of larger economic or social situations that are in

themselves stressful for communities dependent

upon mining – and may in themselves have con-

tributed to the cessation of mining activity.

Factors contributing to cessation of mining activi-

ties include

inter alia

(largely after Environment

Australia (2002a; 2002b), and Smith & Under-

wood (2000):

depletion of mineable reserves, that is as a re-

sult of the total extraction of the mineral re-

serves within the physical limits of a deposit

or the mine area;

unexpected changes/deterioration in geologi-

cal conditions;

changes in market conditions;

changes in other external economic factors

that make reserves unworkable at a given time

(changes in liability conditions should be in-

cluded in this category);

financial (non)viability of the company;

adverse environmental conditions or;

adversepolitical conditions or social disruption.

Further, it is important to note that in some cases

mining may only be suspended for a period of time

and the project is placed under care and mainte-

nance (Environment Australia, 2002a). How long

this period is – or how intensive the degree of “care

and maintenance” is, may vary significantly (Envi-

ronment Australia, 2002a, 2002b; Environmental

Protection Agency, 1995a; Robertson & Shaw, 1998;

Robertson, 1998). However, in circumstances where

it is clear that economic or other limits of the opera-

tions have been reached, decommissioning and fi-

nal closure is required for such sites as well. In some

instances, the delineation between a mine officially

categorised as being on care and maintenance – and

one that is abandoned may be difficult to make.

closure and abandonment of mines

why do mines cease

activityandhowdoes

this affect closure?

67. The reader is reminded, that until relatively recently in a limit-

ed number of countries, that decommissioning and closure works

were generally not required.

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