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Geotechnical News • September 2012
WASTE GEOTECHNICS
Putting tailings on ice
Vivian Giang
Although water and oil don’t mix, Dr. Dave Sego has found that ice
and oil make a perfect research combination.
Dr. Dave Sego is a world-renowned
expert in permafrost engineering
research and oil sands tailings research
– two fields that on first glance could
not seem further apart. Yet Sego has
skillfully applied his expertise in
permafrost engineering to oil sands
tailings and mine waste management
research. How did he make the con-
nection?
What started off
as an “innocent
question” from a
fellow colleague
and mentor
turned out to be
a large boon to
the oil sands and
mining indus-
tries.
In 1990, at the
apex of perma-
frost engineer-
ing research
in Canada, Dr.
Norbert Morgen-
stern approached
Sego and asked,
“If you froze
and thawed
mature fine
tailings (MFT),
how much
water would be
released?” Sego,
who at this point
never researched
oil sands tailings,
asked what the
density of MFT was
(1.2-1.3 t/m3), turned to a frozen soil
engineering textbook and found out
that 50% water would be released.
With a slightly knowing smile,
Morgenstern suggested Sego, then an
Assistant Professor at the University
of Alberta, write a research proposal.
From that moment to this day, Sego
has established a record of success-
fully incorporating his passion for
permafrost engineering to the most
challenging mine waste management
projects in Canada’s northern regions.
With the re-emerging interest in
northern development and subsequent
need for geotechnical engineers with
expertise in permafrost, Sego contin-
ues teaching permafrost engineering
through short courses at the University
of Alberta’s Geotechnical Centre. In a
country that has over 50% of its land-
mass covered in permafrost, Sego’s
cold regions research and courses have
been important in Canada, especially
as permafrost engineering had greatly
subsided during the mid-1990s.
“Between 1991 and 1995, three out
of five cold facilities dedicated to per-
mafrost engineering in Canada closed,
leaving only the University of Alberta
and University of Laval with perma-
frost research capabilities,” says Sego,
now a Professor Emeritus at the Uni-
versity of Alberta. Additionally, there
had not been a PhD in Permafrost
Engineering awarded at the University
of Alberta since 1991. Sego currently
is co-supervising three doctoral candi-
dates who will be the first to graduate
with PhDs in Permafrost Engineering
at the University of Alberta in over
two decades. Those students are cur-
rently working on leading research
in Canada’s north, including on the
Diavik Mine Waste Rock Project.
Although much of his northern mine
waste research was a natural result
of his Arctic-related research, Sego’s
permafrost knowledge significantly
contributed to oil sands tailings
research and management in northern
Alberta. “In the mid-90s, we con-
ducted full-scale field experiments to
Dr. Dave Sego standing on oil sands MFT after a one-year
cycle of freeze thaw and drying (circa 1992).
