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Geotechnical News • December 2019
the assessment and mitigation of
pipeline geohazards. This impor-
tant philosophical point drives a
key technical focus to incorporate
the vulnerability or structural
capacity of a pipeline in estimating
the probability of failure.
2. So long as the geohazard assess-
ment process workflow is transpar-
ent and yields repeatable results,
there are many sound approaches
to assess pipeline geohazards.
In some cases, there are many
commonalities and a high degree
of concordance between differ-
ent approaches used by various
practitioners.
3. Results of pipeline system-wide
screening level geohazard assess-
ments may not be necessarily well
suited for direct conversion into
site-specific designs. Supplemental
design approaches and associated
levels of effort are typically re-
quired to develop detailed site-spe-
cific initial designs or operational
mitigations for areas prioritized by
the screening process.
4. Design stage pipeline geohaz-
ard assessments should be well
suited to serve as the foundation
of geohazard integrity manage-
ment planning. In the case of new
greenfield pipeline developments,
the geohazard assessment may be
well suited to support construction
planning and an estimation of the
project’s footprint as indicated by
the relationship presented in Fig. 6.
5. Target geohazard management risk
levels or probabilities of failure
developed for other contexts (e.g.,
urban planning, residential devel-
opment, or other industries) may
not be practically transferable to
the pipeline geohazard risk context
and should be adopted only with
due diligence to demonstrate appli-
cability in relation to pipelines.
6. In managing pipeline geohazards,
it is prudent to monitor both the
cause (the geohazard process)
and the effect (i.e., the pipeline’s
response). Such approach cor-
roborates the measured pipeline
response and in certain cases
supports forecasting the optimized
timing of mitigation interventions.
Conclusions
Geohazard assessment is a vital part of
new and existing pipeline projects to
reduce the risk of potentially signifi-
cant incidents. The state-of-the-art is
evolving rapidly. The book described
in this article is a snapshot of the
current state-of-practice but provides
guidance in rationalizing qualitative
and quantitative information in assess-
ing the risk posed by geohazards that
is applicable for the foreseeable future.
The book is available at
References
ASME B31.8S-2016 Managing
System Integrity of Gas Pipelines,
American Society of Mechanical
Engineers, New York, NY
Canadian Standards Association
CAN/CSA-Z662-15 Oil and Gas
Pipeline Systems. Mississauga,
Ontario.
CEPA. 2017. 2017 Transmission
Pipeline Industry Performance
report. Available at website
/ wp-
content/uploads/2017/07/CEPA_
PerformanceData_E.pdf
National Energy Board. 2011. Focus
on Safety, a Comparative Analysis
of Pipeline Safety Performance.
Rizkalla, M. (ed.). 2008. Pipeline Geo-
environmental Design and Geo-
hazard Management, American
Society of Mechanical Engineers
(ASME). 353 p.
Rizkalla, M., and R.S. Read, eds.
2019. Pipeline Geohazards: Plan-
ning, Design, Construction and
Operations. American Society of
Mechanical Engineers (ASME).
824 p.
Moness Rizkalla, M.Eng., P.Eng.
Visitless Integrity Assessment Ltd.
Lacey Court, 344 12th Ave. SW
Calgary, Alberta, Canada T2R 0H2
+1.403.681.0842
Rodney S. Read, Ph.D., P.Eng.,
P.Geo., P.Geol.
RSRead Consulting Inc.
117 Sheep River Bay
Okotoks, Alberta, Canada T1S 1R3
+1.403.850.5754
GEOHAZARDS
Figure 6: Role of geohazard assessment in an integrated project framework.
