geotechnically speaking.issue 5
TRANSCRIPT
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02 Threading a needle through Olympic
venue with B.C. hydropower project
03 Out of the ashes: expertise in dams,
soil mechanics aids U.S. coal plants
04 Soil covers in northern climates:
seeking better solutions to burying
problem wastes
05 News from Golder’s
Ground Engineering Group
06 2009 and 2010 Milligan Awards
07 Going where the wind blows:
grounding turbines in varied terrains
07 CO2 sink or swim: testing carbon
capture in Ketzin’s saline aquifer
Issue 4 • 1st Quarter 2009
Golder marked 50 years in 2010. The company has grown into a global operation over this time. Through
the vision of our founding fathers and our collective will to maintain technical excellence and innovation into
existing and new market sectors, we are a sustainable entity of which we can be proud.
It is fitting therefore that this 50th anniversary edition of Geotechnically Speaking (GtS) highlights some
of the diverse and innovative ways that Golder is providing ground engineering services in efficient and
sustainable energy development and allied fields. The demand for energy (nuclear, hydro, oil and gas) and
for efficient methods for dealing with the waste from these activities keeps growing, and we are also active
in these new markets.
Areas where we are providing geotechnical expertise include the development of run-of-the-river
hydroelectric power schemes, developing and applying advances in critical state liquefaction research to coal
ash impoundments for the coal-fired power industry, wind farm power generation, and soil cover design in
cold regions to mitigate the negative environmental impacts of waste rock and tailings from uranium mining
operations.
This issue also highlights Golder’s recognition of our contributions to excellence by announcing the winners
of the 2009 and 2010 Milligan Award for technical papers published by Golder staff in the field of ground
engineering.
Paul Schlotfeldt Senior Rock Mechanics Engineer, Squamish, BC, Canada
From Earth to Energy
CRAZY HORSE FIELDPROGRAM CAPTIONGOES HERE
TAKING ROOT IN THIS RUGGED TERRAIN IS A NETWORK OF
48 VESTAS V90 WIND TURBINES. BEGUN BY EARTHFIRST
CANADA AND CARRIED FORWARD BY PLUTONIC POWER AND
GE ENERGY FINANCIAL SERVICES, THE COMPLETED WIND
FARM WILL DELIVER 333,000 MEGAWATT-HOURS PER YEAR,
THE LARGEST OPERATING WIND FARM IN BRITISH COLUMBIA
(SEE PAGE 7).
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CHARLIE HARRISON AND RICH HUMPHRIES
SQUAMISH, CANADA
Nestled in British Columbia’s rugged Coastal
Mountains, the bobsleigh track built for the 2010
Winter Olympics is one of the fastest and most
scenic in the world. Running beside that track is
another, less visible but equally ambitious con-
struction project—the Fitzsimmons Creek Hydro
Project. This run-of-river hydroelectric plant will
harness the energy of the water flow to generate
7.5 MW of electricity—enough to power the sum-mer and winter operations of the nearby Whistler
Blackcomb resort.
The small footprint of a run-of-river project makes
it an environmentally attractive option for renew-
able energy. But the limited space in the valley of
Fitzsimmons Creek presented the team with an
array of geotechnical, hydraulic, and construction
challenges. Surmounting them in time for com-
mercial operations to begin in 2010 has required
close cooperation and coordination between the
design team (RSW/Golder), the contractor (Ledcor
CMI), the developer (Innergex/Ledcor Power), and
the Vancouver Olympic Committee.
Placing the penstock
Chief among the challenges was the placement of
the penstock, the pipeline used to channel water
from the intake point on the creek to the power-
house 4.5 km downstream--an elevation drop of
nearly 250 m. Initially, the developers had planned
to install the penstock prior to, or in conjunction
with, the bobsleigh track, which began construc-
tion in 2005. However, permitting and regulatory
issues delayed the installation of the penstock un-
til after the bobsleigh track was completed. That
meant the penstock had to be “shoehorned” into
the snow cat road, between the utilities for thebobsleigh track and the edge of a steep natural
slope that drops down to Fitzsimmons Creek.
The proximity of the nearly completed Olympic ven-
ue posed several potential concerns, including the
risk of undermining the newly constructed retain-
ing walls and possible mobilization of deep-seated
slope instability. Through the area adjacent to the
bobsleigh track, the team had to thread the pipe
alignment between potentially unstable slopes,
the bobsleigh track, and the utilities for the track.
This necessitated a number of sharp bends where
concrete anchor blocks, typically 2.2 m wide by 2.2
m high were placed. In three locations where theblocks are on slopes greater than 20°, additional
anchors were incorporated.
Where the penstock had to be constructed near or
at the crest of some very steep slopes (35° to 44°)
of marginal stability—particularly at the Men’s
Start area, and at curves 4 and 7 of the track—
the slopes were further stabilized. Micro piles,
containing 32 mm to 42 mm diameter reinforcing
steel bars, were installed vertically into the slope
to increase the sliding resistance.
To further lessen the potential for a slide, light-
weight cellular concrete fill was used in some
areas around the penstock. This consists of a ce-
ment slurry infused with a foaming agent to pro-
duce a hardened concrete product that weighs less
than water, with a strength that can reach upwards
of 1 megapascal (145 psi).
Another concern was the secure placement of
the powerhouse. In the downstream sections ofthe project, the slopes are particularly steep; at
the powerhouse site, the incised valley is roughly
60 m deep. Hazard assessments identified sev-
eral ancient and recent slope failures in the area,
the most notable being the feature known as the
Fitzsimmons Slump, on the opposite side of the val-
ley from the new penstock and powerhouse.
Protecting the powerhouse
To keep it out of the line of debris flows and out-
wash flooding from the creek, the
powerhouse was tucked in at the
toe of a steep natural slope. The
area available for the powerhouse
and supporting infrastructure
was relatively small and uneven,
necessitating a steep rock cut in
weathered and sheared bedrock
at the base of the natural slope.
The resulting cut slope is about
20 m in height and has shallow
overburden at the crest of the cut
face. A slope angle of 56 degrees was selected to
minimize the rock support needed, so only draped
mesh is required to contain surface ravelling.
The narrow confines of the creek also governed the
design of the intake and spillway structures. To ac-commodate the high sediment load during flood
conditions, a Coanda-type intake was installed. The
Coanda is designed to be self-cleaning: an accelera-
tion plate at the head of the Coanda’s 1 mm screen
increases the velocity of the water to the point
where all debris passes over the weir, preventing de-
bris and large sediment from entering the penstock.
A significant concern were the soft sediments on
which the intake and spillway had to be constructed.
Detailed seepage analyses were carried out to deter-
mine whether a cut-off wall, an upstream impervi-
ous blanket, or other measures would be required
to limit under-seepage and control uplift pressures.These analyses indicated that no special measures
were necessary, resulting in significant savings for
the project. Lock blocks covered by concrete slab
were installed downstream of the intake and spill-
way to direct the water jet further downstream, min-
imizing the potential for undermining the structures.
Although space constraints and complex geology of
the site added greatly to the challenges of design
and construction, the Fitzsimmons Creek project
has thrived. There was no interference with the op-
eration or infrastructure of the bobsleigh track, and
the hydro project began producing power in Au-
gust. Under a purchase agreement with BC Hydro,
the plant will contribute 33,000 megawatt-hours
per year to Canada’s supply of clean electricity.
Threading the Needlethrough an Olympic VenueBuilding a world-class sports track in rugged terrain in time for the
Vancouver Games was a feat of engineering. Building a hydroelectricplant in the same valley was a world-class challenge.
FROM TOP: THE DOWNSTREAM PORTION OF THE HYDROPROJECT. THE PENSTOCK UNDER CONSTRUCTION. THECOMPLETED POWERHOUSE AT THE BASE OF A PRECIPITOUSROCK CUT.
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On December 22, 2008, the coal ash impoundment
at the Tennessee Valley Authority’s Kingston plant
failed catastrophically after reaching some 80 feet
above natural grade. An estimated 5.4 million cubic
yards of slurried ash flowed rapidly into the adja-
cent Emory and Clinch rivers. Several properties
were damaged beyond repair, a railroad was bur-
ied, and utilities were disrupted.
The impoundment failure is one of the largest land-
based environmental disasters in the United States,
with clean-up costs currently estimated at over $1
billion. The incident prompted the U.S. Environ-
mental Protection Agency (USEPA) to review the
federal regulations that govern the disposal of wet
coal combustion residuals, or CCRs, which are pro-
duced primarily by coal-fired power plants.
In June 2010, USEPA issued a proposed rule con-
taining two regulatory options for comment by
industry and the public. Both options require clo-
sure or retrofits to impoundments, use of compos-
ite liner systems, and much greater emphasis on
groundwater monitoring and structural stability of
the impoundments.
Review of the inventory of wet CCR impoundments
across the United States shows that many of the
existing surface impoundments and ash landfills
are unlined, and many do not possess a dedicated
groundwater protection and monitoring system.
Under the new CCR regulations, impoundments
could require a retrofit of liners and seepage col-
lection and control systems. Different water man-
agement practices during operation are likely, and
some plants may convert to dry handling and dis-
posal of CCRs.
A Thorough Going-Over
USEPA has highlighted the importance of assessing
impoundment structural stability in its new ruling
on the disposal of CCRs. Indeed, surface impound-
ments that cannot demonstrate adequate stability
within 5 years of the effective date of the rule will
be required to close. Golder is responding to the
heightened awareness of CCR impoundment stabil-
ity issues by putting its geotechnical expertise to
work in assessing and mitigating coal ash impound-
ment risks.
Typically, this begins with desktop studies and
walkover inspections to evaluate the condition of
the surface impoundment. Golder recently per-
formed visual inspections of embankment dam
structures for American Electric Power at several of
its ash pond facilities, as part of AEP’s internal risk
management program.
In the initial phase of the project, Golder reviewed
information on the impoundments provided by
AEP, including design, construction and repair re-
cords, prior inspection reports, and instrumentationmonitoring data. Golder personnel then physically
inspected inflow and outflow structures, upstream
and downstream slopes, dam crests and toes, as
well as abutments and groins. Existing monitor-
ing devices, including piezometers, surface water
weirs, dam internal drains, and settlement monu-
ments were examined, and piezometric water
levels, and flows from internal drain outlets and
seepage were measured. After reviewing monitor-
ing data and evaluating the conditions of each im-
poundment, we were able to give AEP site-specificassessments and recommendations.
Insights from Soil Mechanics
In cases where large ash ponds are located on weak
foundation layers close to large bodies of water,
as at TVA’s Kingston facility, a desktop study and
walkover inspection may not shed adequate light
on the potential geotechnical risks, particularly
those involving deep-seated failure mechanisms in
the foundation. The CCR material is also quite dif-
ferent from other soils, in that it has spherical par-
ticles (Figure 1), which form as a result of the high
temperature at which the coal is burned. Theseparticles can take on loose packing arrangements,
and are potentially more susceptible to contraction
during shear. Excess pore water pressures are gen-
erated during shear and can lead to a liquefaction
flow failure similar to that observed at Kingston.
In our years of work on mining and offshore proj-
ects, Golder has evaluated numerous hydraulic fills
using specially developed field, laboratory, and an-
alytical techniques that are rooted in fundamentalsoil mechanics. The research work on liquefaction
performed by Golder’s staff over the last 30 years,
and published in the 2006 text book “Soil Lique-
faction: A Critical State Approach,” by Golder’s Ken
Been and Mike Jefferies, can be applied to the as-
sessment coal ash impoundment stability risks.
Graham Elliott, Rafael Ospina, and Ken Been from
Golder presented one application of this research at
the May 2010 conference of the American Society
of State Dam Safety Officials in West Virginia. They
explained how the so called “state parameter” (see
Figure 2), or difference in void ratio of the material
at its in situ stress and the void ratio on its criti-
cal state line at the same stress level, is a measure
of the degree of brittleness of the material. In this
way, the state parameter can be used to identify
contractant material behavior (with consequent
increased pore water pressure during shear) and
dilatant behavior.
The state parameter has been shown to be a good
predictor of liquefaction susceptibility (induced
by significant contractant shear strains) in a wide
range of hydraulic fills from around the world, and
appears to be applicable to coal ash as well. The
state parameter is best evaluated using a combina-tion of cone penetration testing (with piezocone
and seismic cone), coupled with laboratory tests on
re-constituted samples of the ash to determine the
intrinsic properties and critical state line of the ma-
terial. This approach obviates the normal problems
of obtaining undisturbed tube samples in loose par-
ticulate materials.
When the state parameter evaluation is used in con-
junction with desktop study information and walk-
over inspections, informed decisions can be made
about stability. As industry and regulators respond
to the new ash regulations in the aftermath of
the TVA Kingston failure, dam safety, liquefactionanalysis, and geotechnical design will be important
tools in assessing and mitigating risks.
Experts in soil mechanics and dam
safety help U.S. power producers to
understand and manage the difficult
byproducts of coal combustion.
Out of the Ashes
GRAHAM ELLIOTT AND RAFAEL OSPINA,
ATLANTA, GEORGIA, USA
FIGURE 2: THE STATE PARAMETER,DEFINED AS THE DIFFERENCE INVOID RATIO OF THE MATERIAL ATITS IN SITU STRESS AND THE VOIDRATIO ON ITS CRITICAL STATE LINEAT THE SAME STRESS LEVEL, IS AGOOD PREDICTOR OF LIQUEFAC-TION SUSCEPTIBILITY IN HYDRAULICFILLS, INCLUDING COAL ASH.
From Elliott, G, Ospina, R.I. andBeen, K. 2010. Static liquefactionof hydraulic fills: implications fordesign, construction, operation andsafety of coal ash impoundments.ASDSO SE Region Dam SafetyConference, Charleston, WestVirginia, May 2010.
0.500
1Mean effective stress
V o i d r
a t i o , e
ψ = e - ec
Current void ratio of the soil
Critical State Locus (CSL)
Contractive behaviour
Dilative behaviour
FIGURE 1: SCANNING ELECTRON MICROSCOPE IMAGE OFCOAL ASH PARTICLES.
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Using detailed seasonal data and the
tools of unsaturated soil mechanics,
Golder researchers look to improve theperformance and longevity of soil cover
systems in northern Canada and other
extreme environments.
DELWYN FREDLUND, JASON STIANSON, & TRACY MCARTHUR
SASKATOON, CANADA
Cover systems are commonly placed over waste rock
or tailings to mitigate against adverse environmen-
tal impact in the energy (e.g., uranium) and mineral
mining sectors. The design of a soil cover system
subjected to northern climatic conditions consti-
tutes one of the most challenging soil mechanicsanalysis faced by geotechnical engineers. Increas-
ingly, soil cover systems are used to mitigate the
negative environmental impacts of waste materi-
als, particularly for waste containment facilities and
remediation of contaminated sites. The concept of
a cover system is straightforward; however, there
are substantial challenges that arise with respect to
design details. Assumptions associated with the de-
sign process can significantly influence the outcome
of the cover design.
In Golder’s work designing cover systems for waste
rock and tailings from mining operations, we are
investigating the complex effects of climate on soilcover design. Our recent study of the several sites
across northern Canada shows that the frozen win-
ter months contribute significantly to the total an-
nual precipitation and water balance at a site.
Elements of a cover system
A soil cover system can be viewed as a thin interface
placed between the atmosphere and the underlying
material strata (Fig. 1). The ground surface either
has moisture coming down in the form of precipita-
tion or going up in the form of evapotranspiration.
To design a cover system, it is necessary to be able
to predict moisture fluxes in and out of the ground
surface, as well as moisture fluxes through the un-saturated soils comprising the cover system. All
elements of that system--atmosphere, cover, and
underlying soils--are highly variable, making the
quantification of the moisture flux boundary condi-
tions challenging.
The first designed cover systems generally consist-
ed of compacted clays. The intent was to construct
a relatively impervious cover overtop of waste ma-
terials. However, with time, the clay covers became
cracked and permeable to the influx of water. The
newer generation of “store and release” cover
systems buffers the effects of extreme climate by
storing water during wet periods and releasing itback to the atmosphere during dry periods. A wide
variety of materials can be used for the cover sys-
tem and the cover
may consist of one,
two or more layers
sandwiched to-
gether to optimize
performance (Fig.
2). The cover mate-rial must be able to
provide sufficient
water storage ca-
pacity and water
release capacity to
accommodate the climatic weather patterns likely
to occur at any time of any year, so the performance
of the cover has to be simulated using past climatic
data, preferably 10 or more years’ worth.
Challenges of northern climates
Soil covers were first designed for regions where
the average annual temperatures were relatively
high and the winter season involved litt le or no frostaction. However, the climatic conditions in northern
Canada are vastly different than those in temper-
ate climatic regions, requiring a revisiting of the as-
sumptions associated with cover design.
To refine our soil cover design models, Golder has
been looking in more detail at northern Canada’s
annual cycle, which can be divided into several dis-
tinct climatic periods: a winter or “inactive” period
that starts at the end of autumn, and an “active”
period that is introduced by the spring thaw period
and continues through the summer growing season.
The physics of moisture flow and water balance at
the ground surface has special conditions attachedfor each of these periods.
The active period is the primary period over which
the numerical modeling is usually performed for
cover design purposes. This is the period for which
infiltration and evaporation can most accurately be
simulated. It is also the period where precipitation
and evaporation are most active. In many cases, the
summer season is the only season of the year that is
simulated using numerical modeling.
However, assumptions made regarding the other
periods of the year can have a significant effect
on the final design. Recent research by Delwyn
Fredlund, Jason Stianson, and Tracy McArthur has
focused on the modelling assumptions associated
with the inactive period and the spring thaw. Dur-
ing the inactive period, the air temperature falls be-
low 0 degrees C and the soil freezes to a depth of
2 or more meters, remaining frozen for about 6 to 7
months. The soil remains relatively dormant while
snow accumulates on the ground surface. During
the spring thaw period, water from the snow melts
and enters the soil or runs off. Given the amount
of annual precipitation in the form of snow, 30%
to 50% of total precipitation, assumptions made re-
garding spring melt and its assimilation at the soil
surface significantly affect the annual water balance
calculations in the soil cover.
Significance of seasons
To evaluate the relative significance of each peri-
od, Golder’s team analyzed 38 years of climatic re-
cords at a site near latitude 48 degrees in Canada.
We found that the empirical assumptions related
to the inactive period can significantly influence
the overall outcome of numerical model results.
Analysis of the annual precipitation showed that
on average, 38.4% of the total precipitation came
during the inactive period, while 61.6% of theprecipitation occurred during the active period.
Soil covers: better solutions to buryingproblem wastes
continued on page 5
AT LEFT: A COVER SYSTEM VIEWEDAS THE INTERFACE BETWEEN AWASTE MATERIAL AND THE CLIMATICENVIRONMENT. BELOW: A SOILCOVER SYSTEM OVER MINE TAILINGSAT A SITE IN CANADA.
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These results reinforce the importance of being able
to more accurately understand the physical process-
es associated with the inactive period of each year.
Potential evaporation calculations performed for
the same 38-year period showed that, on average,
16.1% of the potential evaporation occurred dur-
ing the inactive period, while 83.9% of the poten-
tial evaporation occurred during the active period.
Moreover, the climate was shown to vary substan-
tially from one year to the next making it necessary
to take climatic variations into account.
Potential versus actual
Potential evaporation quantifies the amount of water
that can evaporate from an open pan of water; how-
ever, it is the “actual evaporation”, AE, from the soilsurface that is required in cover design. The sun can
be visualized as pulling water upward while the soil
attempts to retain the water. Consequently, there is a
struggle between the net radiation from the sun and
the suction (negative pore-water pressure) in the soil.
Analyses to compute net moisture flux conditions at
the ground surface were not part of historical soil
mechanics. However, these calculations form an
important part of the application of unsaturated
soil mechanics and are a requirement for Soil Cover
design. The calculation of net moisture flux at the
ground surface involves numerous assumptions and
extensive computer simulations. The ground surfaceforms a moisture flux boundary in the sense that wa-
ter is either entering the ground surface in the form
of precipitation or it is leaving the ground surface
through (actual) evaporation, AE, or evapotranspira-
tion, ET. Water may also be shed through runoff, R.Each of these quantities must be determined over
a period of many years as part of the cover design
methodology.
Golder engineers have been involved in numerous
studies that require the calculation of the water bal-
ance at ground surface as part of the design or evalua-
tion of soil cover systems. We believe that it is possible
to compute design values for “actual evaporation” at
the ground surface as well as provide an estimate
for the transpiration associated with vegetation on
ground surface. The calculations involve the solution
of nonlinear partial differential equations for heat and
water mass movement. While these computations arecomputationally demanding, we believe that we are
at the frontier in applying numerical modelling simu-
lations to cover design.
Golder’s research suggests that there needs to be
further study of the assumptions and procedural
steps associated with the engineering design proto-
col for soil covers in northern Canada. Engineering
design procedures have emerged for active period
of each year; however, there needs to be further at-
tention given to numerical simulation of the winter
and spring periods. By refining our assumptions
about local climate and the resulting fluctuations of
moisture at the ground surface, we can improve theperformance and longevity of soil cover systems in
extreme environments.
SOIL COVERS CONTINUED FROM PAGE 4
Ashlu Creek hydroelectricproject earns award of merit
Golder Associates Ltd. and project partners RSW
inc. and Hatch Mott MacDonald were recognized
with an award of merit by the Consulting Engineers
of British Columbia (CEBC) for technical excellence
and innovation on the run-of-river Ashlu Creek
Hydroelectric Project. Rich Humphries, Paul Schlot-feldt, Charlie Harrison, Tammy Shore, and Cortney
Palleske were the key members of the Golder team
that completed detailed, fast-track engineering for
the project, which will supply enough electricity for
24,000 homes each year in British Columbia.
It was one of 13 awards in five categories present-
ed at CEBC’s gala event in April 2010. One Award
of Excellence and at least one Award of Merit are
presented annually in five categories: buildings;
municipal; transportation; natural resource, energy
and industry; and soft engineering.
Dennis Becker honoredwith R.F. Legget Medal
In September 2010, Dennis
Becker, Principal and Senior
Geotechnical Specialist in
the Calgary, BC office, won
the Canadian Geotechni-
cal Society’s R.F. Legget
Medal. Dennis received a
standing ovation from the
500 attending delegates as
he accepted the top honor from the geotechnical
community in Canada.
The prestigious R.F. Legget Medal is presented
annually to an individual who has contributed
achievements of permanent significance to the
field of geotechnical engineering in Canada, and to
the development of an understanding of the inter-
relationship of civil engineering and engineering
geology in Canada.
Past winners include Victor Milligan, John L. Sey-
chuk, Norbert R. Morgenstern, Jack Clark, Del
Fredlund and David M. Cruden.
Earlier in 2010 Dennis also won the Julian C. Smith
Medal for “engineering achievement in the devel-
opment of Canada” from the Engineering Instituteof Canada (EIC), which represents all engineering
disciplines.
News from Golder’s Ground Engineering Group
Golder helps to re-openkey road around Gibraltar
In February 2002, a major rockfall at the northern
portal of Dudley Ward Tunnel resulted in the death of
Brian Navarro, a driver exiting the tunnel at the time.
The tunnel, which completed a ring road around theRock of Gibraltar, was immediately closed until an
investigation of the rockfall fatality was undertaken.
Golder was commissioned by the Government of Gi-
braltar to conduct a rock fall risk assessment, which
identified a need to upgrade the existing rockfall
protection measures at the tunnel portal prior to the
road being re-opened to the public.
In December 2008, Golder was authorized to pro-
ceed with the detailed design of the upgrades, which
included a rockfall canopy of
100m extending from the rock
tunnel portal; construction of
400m of high-capacity catchfences on the northern approach
road to the tunnel; and demoli-
tion of the windy single line road
and adjacent structures to allow
construction of a new improved
two-way highway.
Stewart Lightbody and Bruce
Cheesman of the Maindenhead
office led the Golder effort. The design team in-
cluded Clark Smith Partnership, who led the high-
way and structural design, and HBS Consulting who
carried out the associated mechanical and electrical
design.
In addition to this core project, Golder was com-
missioned to carry out a road-widening plan at the
approach of Dudley Ward Northern Approach Road.
This included soil nailing and shotcreting around the
East-West Admiralty Tunnel, as well as upgrading
and maintenance of the unlined 720m long rock tun-
nel and the southern portal.
Despite the severe restraints placed on Golder, the
£10.6m projects were completed within budget on
November 1, 2010, allowing the re-establishment of
a route all around the Rock.
An official opening took place on
November 2, 2010 by the Chief
Minister of Gibraltar, Peter Ca-
ruana. Stewart Lightbody and
Bruce Cheesman were invited
to attend the opening ceremony
(photo at left). The section of
road from the Dudley Ward Rock
Tunnel to the East-West Admiral-
ty/ComCen Tunnel was renamed
Brian Navarro Way in memory of
the tragic loss.
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Krzewinski takes helm of ColdRegions Development Studies
Tom Krzewinski, Principal
and senior geotechnical
engineering consultant in
Golder’s Anchorage, Alaskaoffice, was named president
of the International Associa-
tion of Cold Regions Devel-
opment Studies (IACORDS).
During his 6-year term, he
will oversee IACORDS as it
focuses on organizing symposiums for experts to
exchange ideas on scientific, technological, and
cultural expertise toward the development of cold
regions.
Tom has been with Golder since 2002 and has over
37 years of experience as a geotechnical, envi-
ronmental, and cold regions engineer. He was in-strumental in the design and construction of the
Trans Alaska Pipeline System (TAPS) and was the
1998 recipient of the the American Society of Civil
Engineers (ASCE) Harold R. Peyton Award for sig-
nificant contributions to the field of cold regions
geotechnical engineering. He is the Alaska Engi-
neering Societies’ 2009 Engineer of the Year, and
winner of the 2010 Can-Am Civil Engineering Am-
ity Award in recognition for his many years of ex-
emplary geotechnical engineering in the northern
U.S. and Canada.
Tom is past chair of ASCE’s Technical Council on
Cold Regions Engineering and past president of the
Alaska Section of ASCE. He served for 12 years
on the IACORDS Board of Directors and will chair
the organization’s next symposium, ISCORD 2013,
which will be held in Anchorage.
Paul becomes first Australianwinner of Wolters’ Prize
Associate Darren Paul from
Golder’s Melbourne, Austra-
lia office has won the cov-
eted Richard Wolters’ Prize
for engineering geology.
The prize recognizes merito-rious scientific achievement
by a young professional and
is awarded by the Interna-
tional Association for Engi-
neering Geology and the Environment (IAEG).
Named for the late Dr Richard Wolters, a past Sec-
retary General of IAEG, the prize has been awarded
biannually since 1986, making Darren the tenth re-
cipient and the first ever Australian winner.
In 2008, Darren was named the Young Profes-
sional Engineer of the Year by Engineers Australia
Victoria Division. Among his notable achievements
is his work as Geotechnical Project Manager forthe world’s tallest building, the Nakheel Tower in
Dubai, UAE.
Elmer et al author newguidebook to old tunnels
The tunnelling expertise of Richard Elmer, senior
geotechnical specialist in Golder’s Chelmsford, UK
office, is featured in the Construction Industry Re-
search and Information Association’s publication,“Tunnels: inspection, assessment, and mainte-
nance.” Part of CIRIA’s collection of best practice
guides, the publication discusses the assessment,
condition appraisal, maintenance, and repair of
the structural elements of existing tunnels, with
a focus on older infrastructure and the construc-
tion materials of the era. Richard was one of three
primary consultants on the publication, which con-
tains over twenty case studies from recent tunnel-
ling works. More information at www.ciria.org
Trevor Carter and Davide Elmo, winners of the
2009 and 2010 Victor Milligan awards for the
best Golder paper on ground engineering, were
honored at Golder’s 2010 Global Principals
Meeting held in October in Vancouver, BC.
The 2010 Milligan Award
went to block cave min-
ing expert Dr. Davide
Elmo of the Burnaby, BC,
Canada office. Davide
and coauthor Doug Stead
of Simon Frazer Universi-ty published the winning
paper, An Integrated Numerical Modelling-
Discrete Fracture Network Approach Ap-
plied to the Characterisation of Rock Mass
Strength of Naturally Fractured Pillars, in
the international journal Rock Mechanics and
Rock Engineering in January 2009.
Estimating rock mass strength is a challenging
proposition in most rock engineering designs and
applications. Davide’s paper describes a method
of numerical modeling of fractured mine pillars
that uses an integrated finite element/discrete
element- discrete fracture network approach tosimulate rock mass failure. This approach makes
it possible to study the failure of rock masses
in tension and compression, along pre-existing
fractures, and through intact rock bridges. The
simulation also allows the generation of complex
kinematic mechanisms that can dictate potential
failure paths in rock masses.
Davide’s paper was one of the 41 papers sub-
mitted by Golder staff in response to the call for
paper submissions in early 2010. Runners-up in
this year’s competition were “Stability of Large
Thickened, Non-Segregated Tailings Slopes” by
A.L. Li, K. Been, D. Ritchie, and D. Welch (second
place), and “Characterisation of Natural Frag-
mentation Using a Discrete Fracture Network
Approach and Implications for Current Rock
Mass Classification Systems” by D. Elmo, S. Rog-
ers, and D. Kennard (third place).
As part of the award, Davide will present this
paper at a number of Golder Associates offices,
web meetings, and learned society meetings.
Also receiving his award
was the 2009 Milligan
honoree, Trevor Carter,
a Principal in the Missis-
sauga, BC, Canada office.Trevor and his coauthors,
Joe Carvalho of Golder’s
Mississauga office and
Mark Diederichs of Queen’s University, published
their winning work, the Application of Modi-
fied Hoek-Brown Transition Relationships
for Assessing Strength and Post-Yield Be-
haviour at Both Ends of the Rock Compe-
tence Scale, in the June 2008 edition of the
Journal of the Southern African Institute of Min-
ing and Metallurgy.
Award History
2010 was the sixth year of the award, which
was named for Golder cofounder and interna-
tionally known ground engineer Victor Milligan
(1929-2009). Past winners include Chris Haber-
field (2005), Nick Shirlaw (2006), Rodolfo San-
cio (2007), Joe Carvalho (2008), Trevor Carter
(2009), and Davide Elmo (2010).
In 2004, Golder’s Ground Engineering Group
honored Vic with the creation of the Victor Mil-
ligan Award, given annually at Golder to the
principal author of the best published paper on
a ground engineering topic. The award will con-
tinue to be given out annually in memory of Vic’s
outstanding contributions to the geotechnical
community within Golder and internationally.
2009 and 2010 Milligan awards presented
News from Golder’s Ground Engineering Group
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Geotechnically Speaking
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8/16/2019 Geotechnically Speaking.issue 5
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© 2011, GOLDER ASSOCIATES CORPORATION. GOLDER, GOLDER ASSOCIATES, ANDTHE GLOBE DESIGN ARE TRADEMARKS OF GOLDER ASSOCIATES CORPORATION.
Wind projects have taken Golder geotechs to
all parts of the globe. (Left) The 128 turbines of
the Waubra Wind Farm harness the wind of the high
plateaus of southeastern Australia. Golder’s work
for Acciona Energy on the largest operating renew-able power project in the Southern Hemisphere in-
cluded geotechnical investigation and design for the
massive turbine footings (Right and on the cover)
For the Dokie Wind Project, Golder undertook a pro-
gram of geotechnical exploration and design that
had teams scrambling across miles of rocky terrain
near Chetwynd, British Columbia.
Going Where the Wind Blows
An EU research project tests feasibilityof keeping carbon dioxide out of the
atmosphere by storing it underground.
CO2 Emissions: Is it Sink or Swim?
CO2SINK is a research project on the storage of
CO2 in an underground geological formation near
the town of Ketzin, west of Berlin. The project is
funded by the EU Commission, the Federal Min-
istry of Economics and Technologies (BMWi),
the Federal Ministry of Education and Research
(BMBF), and industry partners. It aims to develop
the basis for storage technology by injecting CO2
into a saline aquifer, following its fate over long
periods of time, evaluating reservoir stability and
integrity.
Cristian Enachescu and Philipp Wolf
of Golder’s Celle, Germany office led the project
team responsible for the small scale (wellbore
and near-wellbore) and large scale (geologicalformation) hydraulic reservoir characterization.
Data from the hydraulic testing program (pictured
above), which included drill stem tests, produc-
tion tests, injection tests, and interference tests
in three ~750 m deep boreholes, was used to
develop the conceptual hydraulic and boundary
model of the reservoir.
The CO2SINK project started in April 2004, and
injection of CO2 began June 30, 2008. Since then,
more than 44,329 tons of CO2 have been injected
uderground.
FROM TOP: GOLDER’S HYDRAULIC TESTING PROGRAMAT KETZIN. DIAGRAM OF THE CO2 SEQUESTRATIONMODEL BEING TESTED (COURTESY CO2SINK.ORG).
About Geotechnically Speaking
Developed by Golder’s Ground Engi-neering Group, Geotechnically Speak-
ing showcases innovative and technically
challenging geotechnical projects that Golder
professionals have worked on throughout the
world.
Issue 5: Ground Engineering Group Lead-
er and Managing Editor: Paul Schlotfeldt.
Editorial and Production Support: Kathryn
Haines
About Golder Associates
At Golder Associates we strive to be the most
respected global group specializing in ground
engineering and environmental services.
Employee owned since our formation in 1960,
we have created a unique culture with pride
in ownership, resulting in long-term organiza-
tional stability. Golder professionals take the
time to build an understanding of client needs
and of the specific environments in which they
operate. We continue to expand our techni-
cal capabilities and have experienced steady
growth, now employing over 7,000 people
who operate from more than 160 offices lo-
cated throughout Africa, Asia, Australasia, Eu-
rope, North America and South America.
7
Issue 5 • 1st Quarter 2011