PASTE & TAILINGS 2020
A global, standard approach to tailings, finally!
Amanda Adams* from Stantec discusses the new Global
Industry Standard on Tailings Management and what it
means for the mining sector
Only 19 months after the January 25, 2019
tailings dam failure in Brazil, a global
tailings standard has been released.
During the August 5, 2020, official on-line
launch of the Global Industry Standard on
Tailings Management, moderator Antonia
Mihaylova announced that more than 2,000
participants had joined. This number represents
only a fraction of the people who contributed to
the development of the Standard, and an even
smaller fraction of the people and companies
who will ultimately be impacted by it.
Stantec’s tailings team has been anxiously
anticipating the release of the Standard
because it will impact both new and existing
projects. Yet during the call, any discussion of
the technical specifics was overshadowed by a
deeply emotional presentation from the guest
speaker, Angelica Amanda Andrade, Community
Representative from Brumadinho. She
eloquently and passionately shared how the
loss of her sister and the other fatalities
impacted her, her family and the entire
Brumadinho community. Her testament
reinforced why this Standard is so important.
Her words “economic recovery is possible, life
recovery isn’t” were a stark reminder of why the
Standard was created and what lies behind it in
human terms.
What guidance is covered in the
Standard?
With that perspective the Stantec tailings team
took a fresh look at the Standard. One of the
most impressive, and complex, aspects of the
Standard is its global nature. Before now there
have been country-specific standards, such as
CDA, MAC and ANCOLD – all which are
internationally recognised – this marks the first
time that a truly global standard is available. It
is divided into six topics; I: Affected
Communities, II: Integrated Knowledge Base, III:
Design, Construction, Operation and Monitoring
of the Tailings Facility, IV: Management and
Governance, V: Emergency Response and Long-
Term Recovery and VI: Public Disclosure and
Access to Information. There are 15 Principles
contained in the Standard, with specific
requirements under each Principle. Topic III
contains four Principles:
n Principle 4: Develop plans and design criteria
for the tailings facility to minimise risk for all
phases of its lifecycle, including closure and
post-closure.
n Principle 5: Develop a robust design that
integrates the knowledge base and minimises
the risk of failure to people and the
environment for all phases of the tailings
facility lifecycle, including closure and postclosure.
n Principle 6: Plan, build and operate the
tailings facility to manage risk at all phases of
the tailings facility lifecycle, including closure
and post-closure.
n Principle 7: Design, implement and operate
monitoring systems to manage risk at all
phases of the facility lifecycle, including
closure.
How does the Standard differ from
current practice?
At first glance this is incredibly simple – just
plan, design, build, operate and monitor the
tailing storage facility (TSF) so risks to people
and the environment are managed at all phases
of the facility lifecycle. At Stantec this is
common practice on our projects. There are
some key differences, such as the Flood Design
Criteria and Seismic Design Criteria. For the Low
and Significant consequence categories the
design criteria are higher than existing Canadian
Dams Association (CDA) guidance. The High
classification is similar. The criteria for Extreme
Consequence facilities is the 1/10,000 year
storm and earthquake.
For those expecting to see the Maximum
Credible Earthquake (MCE) as the seismic
criteria there is a footnote which says “selection
of the design ground motion should consider
the seismic setting and the reliability and
applicability of the probabilistic and
deterministic methods. The MCE is part of a
deterministic approach that can govern in some
areas.” The Standard also explains that
“Maximum Probable Precipitation” (PMP) or
“Probable Maximum Flood” (PMF) are terms
sometimes used to denote extreme hydrological
events. The concepts of PMP and PMF are
acceptable for assigning flood loading if they
meet, or exceed, the requirements above for
Extreme Consequence Classification. This will
become very relevant for existing facilities with
Very High or Extreme Consequence
classification which have been designed using
the PMP and MCE, and now need studies to
evaluate the 1/10,000 storm to see if the design
PMP is higher. Specific clarification on which
areas are governed by the deterministic
approach is not provided.
There is also a new requirement which states
that if a classification other than Extreme is
used for design, “the feasibility, at a proof of
concept level, to upgrade to the design for the
P16 International Mining | SEPTEMBER 2020 Supplement