Geotechnical News • March 2018
53
WASTE GEOTECHNICS
The authors anticipate that the findings
of the dam safety research project
will help the regulator assess risk and
manage tailings dams undergoing
decommissioning and reclamation;
provide clear regulatory requirements
to operators of how to move tailings
dams from active care to passive care
to fully decommissioned structures;
and establish dam (or non-dam) safety
criteria for long time frames.
With many of Alberta’s coal mines
scheduled to close by 2030, the need
for clarity regarding the correspond-
ing risk and processes involved in
closing and reclaiming tailings dams is
immediate. The AER will be required
to ensure that appropriate methods
are being used and appropriate failure
modes are being considered through-
out the process of dam conversion into
a landform. These methods and modes
have not yet been fully assessed.
The research findings will also be
essential to the province’s understand-
ing of the liability associated with
TSFs, both in terms of time to deli-
censing (where possible) and in terms
of the amount and type of maintenance
to be expected for that same time
frame.
Long-term performance of tailings
dams is an international issue. It is
hoped that the results of this project
will help regulators and operators in
Alberta and elsewhere prevent dam
failure and poor dam performance
post-closure. The Obed tailings dam
breach cannot be reversed. However,
the authors are optimistic that the
creative sentence for this offence
will advance understanding of the
full scope of potential failure modes,
maintenance, monitoring, and plan-
ning necessary to achieve successful
closure of these structures.
References
Alberta Energy Regulator. (2017).
‘‘Guilty plea leads to $925,000
penalty for Obed Mountain Coal
Mine spill.’’
/
about-aer/media-centre/news-
releases/news-release - 2017-06-
09.
Eaton T. (2016). “Tailings Dams,
Safety and Decommissioning.”
Keynote presentation at the
International Oil Sands Tailings
Conference 2016 (unpublished).
Kupper AG. et al. (2013). “De-licens-
ing Oil Sands Tailings Dams—
When Is a Dam No Longer a
Dam.” Keynote address at Tailings
& Mine Waste 2013, published by
CRC Press.
Morgenstern NR. (2010). “Improv-
ing the Safety of Mine Waste
Impoundments.” Presentation
at Tailings & Mine Waste 2010,
published by CRC Press.
Provincial Court of Alberta. (2017).
“Agreed Statement of Facts,
Docket No. 151258456P1 &
160061354P1.”
.
aer.ca/compliancedashboard/
enforcement/201706-04_Agreed-
StatementofFacts_PrairieMines
_Obed_2013-006.pdf
Neeltje Slingerland
is a PhD candidate
University of Alberta, Department of
Civil and Environmental
Engineering,
7-203 Donadeo Innovation Centre
for Engineering,
9211 - 116 Street NW, Edmonton,
Alberta, T6G 1H9,
Haley Schafer
is a PhD student
University of Alberta, Department of
Civil and Environmental
Engineering,
7-203 Donadeo Innovation Centre
for Engineering,
9211 - 116 Street NW, Edmonton,
Alberta, T6G 1H9,
Tim Eaton
Senior Advisor at the Alberta Energy
Regulator,
Suite 1000, 250 5 Street SW,
2P 0R4,
