Geotechnical News • June 2016
41
WASTE GEOTECHNICS
• Aboriginal communities are being
impacted by the cumulative effects
of altered land, not solely mining,
so a regional land-use approach is
necessary in planning
• The term ‘Lifescapes’ was quoined
referring to the constant use of
land from pre-mining (this may be
difficult to identify with untrained
eyes) to post-mining periods,
implying a continuum into the
future and tying together people
and place. It was similarly agreed
that the term “closure plan” does
not adequately reflect what such a
plan needs to do – ‘Sustainability’,
or ‘Life Cycle’ Plan may be more
appropriate.
The Roundtable concluded with a
consensus that there is potential for the
landscape architecture profession to
fill the gaps where traditional mining
professionals are lacking in closure
planning. The group of approximately
35 representatives that took part
closed with the intention to test their
collaborative potential on a study site
through a design charrette (a graphic
brainstorming session frequently used
by architects to generate ideas) in the
near future.
Conclusions
The landforms that nature has devel-
oped over millions of years are in a
state of equilibrium; if our objective
is to do the same for post-mining sites
it makes sense to mimic this example
albeit over an expedited timeframe.
This idea appears to be catching on:
the survey results show a slight trend
towards more naturalized approaches
as opposed to heavily engineered
or controlled methods. One of our
challenges as an industry is that mine
closure is not typically a revenue gen-
erator, and traditional approaches are
far less costly than “naturalized” ones.
Landform grading is one of the great-
est expenses in a closure budget, but
it also has one of the greatest (posi-
tive) impacts on future performance
and maintenance costs. Unfortunately,
“form follows function” has been
replaced with “form follows profit” as
a recurring guiding principle of recla-
mation works, and this may contribute
to the poor achievement: the average
success rate was 47.5% for geotechni-
cal goals.
Events such as the ‘Land-
scapes of Extraction
Roundtable’ epitomize a
new trend in closure
planning, bringing
together mining and
land-use professionals to
design improved
post-mining landscapes
With the exception of avoiding ongo-
ing water treatment and maintenance
of tailings impoundments, all goals
have been in existence over the last
twenty years. Why then, are our
achievement rates for these goals so
low? One theory is that poor success is
not a symptom of inability to achieve
the performance target, but a reflec-
tion of poor transfer of knowledge,
implementation follow-through, and
post-closure monitoring. Another
theory is that while these individual
goals are identified, the sub-goals rela-
tive to various specialists (pedologists,
hydrologists, geotechnical engineers,
etc.) have not been well defined,
suggesting that corresponding tech-
niques and approaches may be equally
ill-defined.
Regardless of survey interpretation,
one conclusion is clear: closure goals
are created to protect human and envi-
ronmental health into the future, and
our track record over the last twenty
years has not significantly improved.
Naturalized solutions appear to be
gaining ground, but there is always
room for new innovations and
approaches when the industry’s public
license to operate is at stake.
Events like the ‘Landscapes of Extrac-
tion Roundtable’ which draw on the
expertise of land-use professions
demonstrate a willingness in industry
and academia to delve outside of their
comfort zones in the search for more
effective and meaningful mine closure
solutions. While the inclusion of such
professionals is not guaranteed to
produce better results, this is a radical
shift from traditional approaches that
are more insulated in nature. A busi-
ness case for closure work involving
naturalized landforms and land-use
professionals will likely need to be
substantiated in order to drive wide-
spread action.
References
DeJong, J., Tibbett, M., & Fourie, A.
(2015). Geotechnical systems that
evolve with ecological processes.
Environmental Earth Sciences
,
73(3), 1067-1083.
Kahn, J. R., Franceschi, D., Curi, A.,
& Vale, E. (2001). Economic and
financial aspects of mine closure.
Natural Resources Forum
, 25,
265-274.
McKenna, G., & Dawson, R. (1997).
Closure Planning Practice and
Landscape Performance at 57
Canadian and U.S. Mines,
Pro-
ceedings of the 21st Annual British
Columbia Mine Reclamation Sym-
posium
, 1997, Cranbrook, British
Columbia, Canada. pp 74-87.
Nicolau, J. M. (2003). Trends in
relief design and construction in
opencast mining reclamation
. Land
Degradation & Environment
, 14,
215-226.
N. Slingerland
Department of Civil & Environ-
mental Engineering, University of
Alberta. E-mail:
N. Beier
Department of Civil & Environ-
mental Engineering, University of
Alberta.
M. Baida
Wax Design, Australia
