2
1 Introduction
We believe that reaching this objective requires significant improvement in many
areas particularly through the application of sophisticated but sustainable quantitative risk assessment and risk management methodologies. These can contribute to
the reduction and eventual elimination of dam failures through risk-based-decisionmaking and risk-informed decision making (respectively RBDM and RIDM).
Following the Federal Energy Regulatory Commission (FERC) Risk Guidelines
(https://www.ferc.gov/industries/hydropower/safety/guidelines/ridm.asp) definition,
Risk Informed Decision-Making (RIDM) applied to dams uses the likelihood of
loading, dam fragility, and consequences of failure to estimate risk. Risk estimates
are then used to decide if dam safety investments are justified or warranted.
For Risk-based decision making we follow the definition given by the Committee
on Improving Risk Analysis Approaches (NRC US 2009). RBDM (http://www.au.af.
mil/au/awc/awcgate/uscg/risk-qrg.pdf) organizes and orders information about potential nefarious events to shore decision makers management choices. RBDM asks
questions like: What can go wrong? How likely are potential problems to occur? How
severe might the consequences be? Is the risk tolerable? What can/should be done to
mitigate the risk?
When comparing the two definitions it results that RBDM can be seen as a subset
of RIDM, the two having a common trunk. In this book we refer to RBDM when
an analysis shores and supports decision making whereas we consider RIDM when
we discuss tactical and strategic risks, extending into formal financial analyses of
mitigative alternatives.
We understand there are indeed companies, consultants and regulators around the
world that have already a high level of commitment to tailings dam safety and have
developed practices that have been instrumental in ensuring the safe operation of
tailings dams under their watch in many countries (see Further Reading at the end of
the book for some examples, among which are pleased to highlight the latest version
of the MAC OMS manual (MAC OMS Guide 2019)). The challenge pointed out in
the keynote lecture by Henry Brehaut at the Tailings Mine Waste 2017 Conference
(Brehaut 2017) is to use this experience as the starting point in the development of
standards, practices and guidelines that must be used by all companies to establish
higher levels of performance, by governments for effective oversight of the industry
and to provide the basis for a high level of public trust (https://www.riskope.com/
2013/05/08/can-we-stop-misrepresenting-reality-to-the-public/) (Oboni et al. 2013).
“Trust us” no longer works; Demonstrated commitment supported by leading edge
risk assessments will.
Higher levels of performance, standards and oversight require better definition of
the quality designation for an industry practice. To this day this generally rests solely
in the eye of the beholder, which is most likely to be the person or organization that
1 Introduction
We believe that reaching this objective requires significant improvement in many
areas particularly through the application of sophisticated but sustainable quantitative risk assessment and risk management methodologies. These can contribute to
the reduction and eventual elimination of dam failures through risk-based-decisionmaking and risk-informed decision making (respectively RBDM and RIDM).
Following the Federal Energy Regulatory Commission (FERC) Risk Guidelines
(https://www.ferc.gov/industries/hydropower/safety/guidelines/ridm.asp) definition,
Risk Informed Decision-Making (RIDM) applied to dams uses the likelihood of
loading, dam fragility, and consequences of failure to estimate risk. Risk estimates
are then used to decide if dam safety investments are justified or warranted.
For Risk-based decision making we follow the definition given by the Committee
on Improving Risk Analysis Approaches (NRC US 2009). RBDM (http://www.au.af.
mil/au/awc/awcgate/uscg/risk-qrg.pdf) organizes and orders information about potential nefarious events to shore decision makers management choices. RBDM asks
questions like: What can go wrong? How likely are potential problems to occur? How
severe might the consequences be? Is the risk tolerable? What can/should be done to
mitigate the risk?
When comparing the two definitions it results that RBDM can be seen as a subset
of RIDM, the two having a common trunk. In this book we refer to RBDM when
an analysis shores and supports decision making whereas we consider RIDM when
we discuss tactical and strategic risks, extending into formal financial analyses of
mitigative alternatives.
We understand there are indeed companies, consultants and regulators around the
world that have already a high level of commitment to tailings dam safety and have
developed practices that have been instrumental in ensuring the safe operation of
tailings dams under their watch in many countries (see Further Reading at the end of
the book for some examples, among which are pleased to highlight the latest version
of the MAC OMS manual (MAC OMS Guide 2019)). The challenge pointed out in
the keynote lecture by Henry Brehaut at the Tailings Mine Waste 2017 Conference
(Brehaut 2017) is to use this experience as the starting point in the development of
standards, practices and guidelines that must be used by all companies to establish
higher levels of performance, by governments for effective oversight of the industry
and to provide the basis for a high level of public trust (https://www.riskope.com/
2013/05/08/can-we-stop-misrepresenting-reality-to-the-public/) (Oboni et al. 2013).
“Trust us” no longer works; Demonstrated commitment supported by leading edge
risk assessments will.
Higher levels of performance, standards and oversight require better definition of
the quality designation for an industry practice. To this day this generally rests solely
in the eye of the beholder, which is most likely to be the person or organization that