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Abstract and Figures

Frequency of tailings dam failures
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CDA 2019 Annual Conference
Congrès annuel 2019 de l’ACB
Calgary, AB, Canada
October 6-10, 2019
CDA 2019 Annual Conference, Calgary, AB, Canada
David M. Chambers, Ph.D., P. Geop., Center for Science in Public Participation, Bozeman, Montana
In 2011 (Chambers & Higman) the authors published the results of their research into worldwide tailings dam failures.
This research, which involved developing the most complete list of tailings dam failures publically available
(, showed the rate of tailings dam failures over the period 1940-2010 was
relatively constant. There are two immediate implications of this finding. First, efforts to implement regulatory,
engineering, and operating changes to lower the rate of tailings dam failures are not having the desired effect. Second,
because the rate is staying the same, and the number of mines is increasing, the number of failures is also rising. In
2017 we (Bowker & Chambers) updated our data to include the half-decade from 2010-2014. We segregated the data
into several different categories in accordance with observed impact, and noted that the failure rate remained
essentially the same for the most important Serious and Very Serious failures. We also found a correlation between
the production of copper ore, an analog often used for metal production in general, and the number of failures. We
now have data for next half-decade, 2015-2019, and will show how this new data relates not only to the trends observed
in previous decades, but also how it compares to the predictions we made for this time period, and what we predict
for the next decade if significant changes to present practices for the design, construction, operation, and closure of
tailings dams are not made.
En 2011 (Chambers & Higman), les auteurs ont publié les résultats de leurs recherches sur les défaillances mondiales
de digues à stériles. Cette recherche, qui visait à dresser la liste la plus complète des défaillances de digues à stériles
accessible au public (, a montré que le taux de défaillances des digues à stériles
au cours de cette période 1940-2010 était relativement constant. Cette constatation a deux conséquences immédiates.
Premièrement, les efforts visant à mettre en œuvre des modifications réglementaires, techniques et opérationnelles
visant à réduire le nombre de défaillances de digues à stériles n’ont pas eu l’effet souhaité. Deuxièmement, comme le
taux reste le même et que le nombre de mines augmente, le nombre de défaillances augmente également. En 2017,
nous (Bowker & Chambers) avons mis à jour nos dones afin d'inclure la demi-décennie de 2010 à 2014. Nous avons
séparé les données en plusieurs catégories différentes en fonction de l'impact observé, et avons constaté que le taux
d'échec restait essentiellement le même pour les plus importantes. Échecs graves et très graves. Nous avons également
constaté une corrélation entre la production de minerai de cuivre, un analogue souvent utilisé pour la production de
métal en général, et le nombre de défaillances. Nous disposons maintenant de données pour la prochaine demi-
décennie, 2015-2019, et nous montrerons en quoi ces nouvelles données se rapportent non seulement aux tendances
observées au cours des décennies précédentes, mais également aux relations que nous avons établies avec les
prédictions que nous avons établies pour cette période, prédire pour la prochaine décennie si les pratiques actuelles en
matière de conception, de construction, d’exploitation et de fermeture des digues à stériles ne sont pas profondément
CDA 2019 Annual Conference, Calgary, AB, Canada
In the last 5 years there have been three highly visible tailings dam failures – Mount Polley, British
Columbia; Fundao, Minas Gerais, Brazil; and, Brumadinho, Minas Gerais, Brazil. The latter resulted in
over 300 dead or missing, many of these mining company employees. What has changed? Unfortunately,
the answer is very little. Brumadinho is only the 3rd largest tailings dam failure in terms of lives lost (the
Mir mine, Sgurigrad, Bulgaria, is the largest; Los Cedros, Tlalpujahua, Michoacán, México in next). There
have been large tailings dam failures in countries with long experience with mining, and with highly
developed regulatory systems, including the US, Europe, Canada, and Australia. Fundao was the largest
tailings dam failure on record in terms of volume of waste released 43.7 Mm3 (Padcal No.2, Luzon,
Philippines, is next at 32.2 Mm3).
What is causing concern is the rate at which these large, highly visible tailings dam failures are occurring.
This paper will demonstrate that the rate at which these failures are occurring has, in fact, remained
relatively constant since 1940. However, if the rate of failure remains constant, but the number of mines
increases, and these mines become larger, then the number of failures, and the size and impact of those
failures, will also increase.
2.1 Background
There are some readily available, and sobering, statistics on tailings dam failures. Tailings dam fail at
approximately 10 to 100 times the rate of water retention dams (Garbarino et. al. 2018). The major failure
mechanisms are overtopping, earthquakes, static failures, etc. (ICOLD 2001). Upstream-type dam
construction is associated with a majority of these failures (Rico 2008).
Yet despite the repeated impacts on public safety, and the financial and environmental impacts to society,
both private and public, and the known existence of these failures for over 100 years, a number of very
basic steps have not been taken. There is no data base of tailings dams, tailings dam failures, or statistics
related to these failures (dam type, height, length, construction materials, etc.) No international or national
institution tracks tailings dam failures (e.g. UN, ICOLD, USEPA, CDA, ANCOLD). And, there is no
financial surety requirement for tailings dam failures.
The latter is important because society often ends up picking up a large share of the costs of catastrophic
dam failures, either in terms of the direct economic costs of cleaning up these failures, or the indirect costs
of the impacts when there is only partial or no cleanup. For example, the cleanup of the dam failure at
Mount Polley has not only been subsidized by the public sector, but many businesses, tribal groups, and
local individuals who suffered economically from the accident, were not compensated for those losses
(Lavoie 2017). In 2015, the author estimated the cost of a catastrophic tailings dam failure was $543 million
(Bowker and Chambers 2015). The accidents at Fundao and Brumadinho have resulted in multi-billion
dollar legal actions by the Brazilian government. Given the immense costs associated with the dam failures
in Brazil, the cost of the average catastrophic dam failure could be over one billion dollars now.
A water reservoir dam is an asset to its owners, making care and maintenance an investment, rather than a
cost. A tailings dam is a financial liability to a mining company. If mining companies were required to
have some form of financial surety, or insurance, for a catastrophic tailings dam accident, not only would
the public receive more reliable compensation for their losses, and government for cleanup costs, but mining
companies would also have a financial incentive to prevent tailings dam failures.
CDA 2019 Annual Conference, Calgary, AB, Canada
2.2 Data Limitations
Today there are only a few regional entities, like British Columbia and Alberta, who have accurate
inventories of tailings dams within their jurisdiction. Because there are no international entities that track
tailings dams, we don’t know the number, types, and operational status of most tailings dams. There is no
institutional incentive to report, collect, or analyze data on tailings dam failures. This is because for
agencies and companies to report this information, they are reporting on their own failures. Few like to
publically declare their own mistakes. And, in countries where press censorship is practiced, it is difficult
to get information about tailings dam failures (e.g. Russia and China).
In an effort to get just an order of magnitude handle on the problem of tailings dam failures, we were forced
to create our own database of mine failures from publically available sources (,
primarily online. This data base of mine failures consists mostly, but not exclusively, of over 300 tailings
dam failures beginning in 1915. Data pre-1940 is limited by lack of records; and a smaller number of events
as tailings impoundment use increased, and as these dams increased in both number and size. It is also
important to note that prior to passage of the Clean Water Act in 1972, it was still legal to dump mine waste
directly into streams in the United States.
2.3 Categorization of mine waste failure events
We initially classified impoundment-related failures into 4 categories – Very Serious, Serious, Other
Accidents, and Other Failures. The Very Serious and Serious categories encompass the most damaging
tailings dam failure events. The number of the Other Accidents and Failures appear to have peaked in the
period from 1960s to the 1980s, and have decreased since then, suggesting that improved management
approaches and technologies have had a positive effect on these categories of failures. Data plotted for the
figures in this paper represent only tailings dam failures, even though non-dam failures data (e.g. waste
dump, sinkholes, etc.) do exist in the data base.
We developed the definitions for the different categories of tailings failures based on our own experience,
and the definitions seem to provide both a meaningful distinction between failure types, and plausible
informational statistical results. For the purposes of this paper, the focus will be on Very Serious and
Serious Failures (defined below), since they are associated with events that impact the public.
Very Serious Failure – multiple loss of life and/or release of 1,000,000 m3 total discharge, and/or
release travel of 20 km or more
Serious Failure – loss of life and/or release of ≥ 100,000 m3 discharge
These definitions are subjective, but as with all new definitions we had to begin somewhere. Ideally we
would have a scale that represented social (human life), environmental (type of habitat and area impacted),
and economic (loss). There is seldom any data on the economic value lost in a tailings dam failure,
environmental damage data is sparse and selective, but human lives lost is typically precise. Nonetheless,
environmental damage needs to be considered. No one would consider Mount Polly, which had no
fatalities, a minor accident.
CDA 2019 Annual Conference, Calgary, AB, Canada
2.4 Data averaging and curve fits for projecting future failures
In order to get meaningful results from the tailings failure data, it must be averaged over a specified interval.
Annual, 5-year, 10-year, and 20-year data average windows have been investigated (see Figure 1).
As can be seen in Figure 1, the statistical fit is better the longer the time-average period, but we have used
a 10-year data average interval because it provides the best compromise between statistical fit and response
to changing event frequency. At some time in the future, in 20 to 100 years, when there is enough data to
provide better response for the 20-year data average interval, that period might become more appropriate
to provide predictions, but at present there is not enough data recorded to provide an adequate prediction
from this interval.
As can be seen from the intercept of the line fit with the far right vertical axis, all of the time intervals
predict approximately 1 Very Serious Failures per year, which is close to the actual rate of occurrence.
It can be seen in Figure 2 that the rate of occurrence for Very Serious and Serious events are quite similar,
and we see a relatively constant rate of failure continuing from 1940 to the present. It might also be argued
that the two should be combined. However, because all catastrophic events will fall into the Very Serious
category, and because the data trend for Very Serious Failures has slightly better regression statistics, it is
useful to maintain the distinction between the two categories.
We also have data on lesser failures, but that information is clearly in a different failure cause and impact
category, and as previously noted is not presented here.
Figure 1: Very Serious Failures by Different Intervals
R² =0. 1214
1940 19 50 1960 19 70 1980 19 90 2000 2010 20 20
5‐Ye arIntervals
CDA 2019 Annual Conference, Calgary, AB, Canada
This relatively consistent failure rate is alarming from two perspectives. First, it suggests that changes to
management approaches, and in technological improvements, have not had a major impact in reducing the
rate of large tailings dam failures. Second, if the tailings dam failure rate remains the same, but as the
number of tailings dams increases, we will see more frequent, and as it turns out, larger tailings dam failures.
In fact, this is what is happening.
Figure 3: Failure Predictions with 2n
and 4t
Order Polynomial Fits
1940 19 50 1960 1970 1980 19 90 2000 2010 2020
Very SeriousFa ilures 4th Orde rPoly.
Very Serio us2 ndOr derP oly.
Poly.(VerySer iousFailures4thOrderPoly.)
1940‐491950‐591960‐691970‐79  19 80‐89  19 90‐99  20 00‐09  2010‐19
Figure 2: Failure Predictions with Linear Fit
1940 19 50 1960 1970 1980 1990 2000 2010 2020
TotalFailuresinDe cade
Linear(V er yS eriousFail ur es)
CDA 2019 Annual Conference, Calgary, AB, Canada
Use of other curve fitting formulas for the data was also investigated. In Figure 3 the use of a second-order
and fourth-order polynomial fits to the failure data are displayed. While there is a better fit statistically, it
can be seen that the curve fit is being biased by the scatter in the data. We believe that using a linear fit to
the data represents the best approach to predicting future events, at least for the present time.
There seems to be a downturn in the data trend beginning in the 1990-99 decade. With a curve fit it is
easier to detect a bias in the predictions made from the data trend. By trying different curve fitting routines,
including polynomial, exponential, and logarithmic, we believe that the linear fit gave the most consistent
trend. Hopefully, with more data, and more reliable data, better interpretation methods can be utilized.
The constant rate of tailings dam failures first became apparent to the author in 2010. At that time the data
available on tailings dam failures was even worse than today. In 2011 we (Chambers and Higman 2011)
published a paper discussing this trend, but at that time only data on total failures was considered. In 2015
we (Bowker and Chambers 2015) developed our definitions for Very Serious and Serious failures, and
published a paper discussing the trends in this segregated tailings dam failure data. It is now 5 years hence,
and again we have data from an additional 5 years to analyze.
In Figure 4 the Very Serious Failures and Serious Failures data available from 1940-2009 is plotted with
associated trend lines. The lower set of lines is for Very Serious data only, and the upper set of lines for
both Very Serious and Serious Failures. Similarly, the data from 1940-2014 and 1940-2019 is plotted. The
Figure 4: Very Serious Failures
R² =0. 8115
R² =0. 8565
R² =0. 8509
R² =0. 8297
R² =0. 7486
R² =0. 8639
1940 19 50 1960 19 70 1980 19 90 2000 20 10 2020
1940‐2019 Se rious+VerySerious
1940‐2015 Se rious+VerySerious
1940‐2009 Se rious+VerySerious
1940 ‐2019Ve rySeri ous
1940 ‐2015Ve rySeri ous
1940 ‐2009Ve rySeri ous
Linea r( 1940‐ 201 9VerySerious)
Linea r( 1940‐ 201 5VerySerious)
Linea r( 1940‐ 200 9VerySerious)
CDA 2019 Annual Conference, Calgary, AB, Canada
Very Serious Failure data shows some improvement in the tailings dam failure rate, on the order on one
less Very Serious tailings dam failure per decade.
The trends for the combined Very Serious and Serious Failures show a consistent lowering rate over three
consecutive periods. There are approximately 30% more Serious Failures than Very Serious Failures, so
the Serious Failures data has more influence on the trend, suggesting that improvements to prevent failures
are having more influence on the Serious Failures, the less-serious events. While this trend is positive, at
this rate of change it would take another 80 years to realize a drop of one order of magnitude for tailings
dam failure rate, approximately the failure rate for water supply reservoir dams.
This analysis predicts there will be, on average, approximately one Very Serious tailings dam failure per
year. In the decade from 2005-2014 there were 8 Very Serious tailings dam failures, and in the decade
2010-2019 (to date) there have been 9 Very Serious Failures (Brumadinho, Minas Garias, Brazil, 2019;
Cadia, New South Wales, Australia, 2018; Vedanta, Jharsuguda, India, 2017; Louyang, Xiangjiang, China,
2016; Fundao-Santarem, Minas Gerais, Brazil, 2015; Mount Polley, British Columbia, Canada, 2014;
Padcal No 3, Benquet, Philippines, 2012; Ajka, Kolontár, Hungary, 2010; Xinyi Yinyan, Guangdong,
China, 2010).
Some interesting implications come out of this analysis.
There is no fundamental engineering reason for tailings dams to fail more often than water retention dams.
So something is happening with tailings dam design, construction, operation, and/or closure that is not
happening with reservoir dams.
There are some significant differences between tailings dams and water retention dams. Tailings dams are
almost always constructed with mine waste, either waste rock or tailings, and use three construction types
downstream, centerline, and upstream. It is not possible to use upstream-type construction for water
reservoir dams, and it would only be possible to use centerline construction for water retention dams if
concrete were utilized. Upstream-type dam construction is associated with most tailings dam failures, yet
is probably the most widely utilized dam construction type for tailings dams because of the lower
construction cost (Rico et. al. 2008).
In addition to different construction types, tailings dams are almost always constructed in lifts, or stages,
one to several years apart. This is related to the availability of dam construction materials (mine waste rock
or tailings), but means that many different individuals, sometimes different companies, and often significant
design changes, lead to potential complications in integrating the different stages.
The Mount Polley Expert Panel Report offered a number of sage suggestions on how to break the cycle of
failure that plagues tailings dams. The overall sense, and explicit observation, of the panelists was that
The Panel firmly rejects any notion that business as usual can continue.” (Expert Panel 2015).
The Panel left the definition of “Business-as-Usual” open to interpretation, but to this author it means:
Wet closures are the best option for PAG waste;
Cost is the primary driver in tailings dam construction;
Risk is focused on risk to mine operators and regulators, not on risk to public safety; and,
Better engineering is the answer to these problems.
CDA 2019 Annual Conference, Calgary, AB, Canada
The author has reviewed the following post-Mount Polley changes to regulatory requirements and
professional organization guidance: the British Columbia Mines Act and Health Safety & Reclamation
Code Part 10 (2017); the Montana Act Revising Metal Mine Reclamation Laws, Establishing Standards for
Tailings Storage Facilities, and Creating Independent Review Panels (2015); Alberta Regulation 205-98
Part 6 Dam & Canal Safety (2018); the Mining Association of Canada Guide to the Management of Tailings
Facilities, Third Edition (2017); and, the Best Available Techniques (BAT) Reference Document for the
Management of Waste from Extractive Industries, European Commission (2018).
The primary response in most of the world to the recommendations of the Mount Polley Expert Panel has
been to require Independent Tailings Review Boards, with the major exception of the European
Commission, which requires an independent review, by only by an individual (Garbarino 2018). It is
also of note that the failed Fundao tailings dam had an independent tailings review board (Fundão Review
Panel 2016). The Mount Polley Expert Panel recommendation for eliminating wet closures are only
minimally addressed in post-Mount Polley regulatory revisions, except for the European Commission
The Mount Polley Expert Panel recommendations for making safety “first” has largely been overlooked.
Most post-Mount Polley regulatory changes make safety one of, but not the primary, consideration in risk
assessment and the design, construction, operation, and closure of tailings dams.
What does the tailings dam failure rate data tell us? It says the failure rate for tailings dams is relative
constant, but with more mines there are more failures, and with larger mines there are larger, more damaging
failures. We can also see that despite the explicit warning issued by the Mount Polley Expert Panel,
Business-as-Usual is continuing.
It may not be surprising, but there is also a correlation between tailings dam failures with increasing waste
production (Bowker and Chambers 2017). If the average grade of ore minerals declines, as it does for most
base and precious metals, and the demand for these metals by society increases, more waste per unit of
metal is produced. This increase in waste production requires more waste storage facilities, resulting in
more and larger tailings dams – a few of which will fail.
What are potential engineering-related approaches to bringing the tailings dam failure rate down? To make
the change from business-as-usual to a new approach to tailings dams will be painful from a process point
of view, and will be expensive – but economic costs society should be willing to pay to avoid the
catastrophic impact on the individuals affected by a catastrophic dam failure.
Some suggested considerations are:
Find an organization to put together a data base on tailings dams and tailings dam failures (dam
type, height, length, construction material, etc.) so that we can understand the nature of the problem.
Find a mechanism to organize an international source for catastrophic tailings dam failure
insurance. Requiring financial assurance for a catastrophic event would only make the mining
industry comply with financial surety requirements that are already levied on similar businesses,
like the oil & gas and chemical industries. Right now, mining is getting a big economic break by
avoiding a financial surety for catastrophic failures. The industry itself would probably be the best
source to organize this funding assurance.
CDA 2019 Annual Conference, Calgary, AB, Canada
Make independent tailings review boards truly independent by making their proceedings, or at least
their determinations, transparent. There are some entities that argue that the deliberations and
recommendations from independent tailings review boards and an operating company should
remain confidential in order to foster open dialog (MAC 2017). But if a company can chose to
ignore the recommendation of an independent tailings review board, the publics only backstop is
regulatory oversight – which didn’t work in the recent instances of catastrophic tailings dam
failures in Minas Gerais and British Columbia.
Make dry closure the starting point for all waste impoundments, even for tailings deposited in wet
impoundments. Wet closures, even for potentially acid-generating waste, should only be
undertaken if it can be demonstrated through formal risk assessment that the long-term risk to
public safety is less with a wet closure than with a dry closure. The Mount Polley Expert Panel
noted: “… the Mount Polley failure shows why physical stability must remain foremost and cannot
be compromised. ... No method for achieving chemical stability can succeed without first ensuring
physical stability: chemical stability requires above all else that the tailings stay in one place.”
(Expert Panel 2015)
Make public safety explicitly the primary (but not the only) consideration in tailings dam risk
assessment. Until safety is explicitly made the primary consideration for the design, construction,
operation, and closure of tailings dams, cost will continue dominate the process. Here observing
human nature is important. For example, it is logical to convince ourselves that upstream-type dam
construction can be done safely, that we understand all of the important engineering factors. But
in following this path we are in essence assigning a risk to future generations to which they have
no input. We build them, but they will ultimately need to take care of them.
Recognize that human factors must be taken into proper consideration in dam design. Anytime
there are people involved in a process, they will inevitably make mistakes. Dam design should
minimize the dependence on human involvement, for example the need for long-term monitoring
and maintenance, and maximize redundancy for dam safety features. The Mount Polley Expert
Panel noted: “Tailings dams are complex systems that have evolved over the years. They are also
unforgiving systems, in terms of the number of things that have to go right. Their reliability is
contingent on consistently flawless execution in planning, in subsurface investigation, in analysis
and design, in construction quality, in operational diligence, in monitoring, in regulatory actions,
and in risk management at every level. All of these activities are subject to human error. Human
error is often, if not always, found to play a key role in technological failures. And human error
will always be with us, as much as we might wish it to be otherwise.” (Expert Panel 2015).
Significantly restrict, perhaps eliminate, the use of upstream-type dam construction. There is too
much risk with upstream-type construction in areas with more than low seismic risk, or in areas
with net-precipitation.
CDA 2019 Annual Conference, Calgary, AB, Canada
Bowker, Lindsay Newland and David M Chambers. 2015. “The Risk, Public Liability, & Economics of Tailings
Storage Facility Failures.” Northern Latitudes Mining Reclamation Workshop.(data updated to 2018).
Bowker, Lindsay Newland and David M Chambers. 2017. “In the Dark Shadow of the Supercycle Tailings Failure
Risk & Public Liability Reach All Time Highs.” Environments 2017, 4, 75.
Chambers, David M. and Bretwood Higman. 2011. “Long Term Risks of Tailings Dam Failure.”,
October, 2011.
European Commission, 2018. Best Available Techniques (BAT) Reference Document for the Management of Waste
from Extractive Industries, in accordance with Directive 2006/21/EC, Elena Garbarino, Glenn Orveillon,
Hans G. M. Saveyn, Pascal Barthe, Peter Eder, European Commission, 2018
Expert Panel (Independent Expert Engineering Investigation and Review Panel). 2015. “Report on Mount Polley
Tailings Storage Facility Breach.” Province of British Columbia, January 30, 2015.
Fundão Review Panel (Fundão Tailings Dam Review Panel) 2016. “Report on the Immediate Causes of the Failure
of the Fundão Dam.” August 25, 2016.
Garbarino, Elena, Glenn Orveillon, Hans G. M. Saveyn, Pascal Barthe, Peter Eder. 2018. “Best Available
Techniques (BAT) Reference Document for the Management of Waste from Extractive Industries, in
accordance with Directive 2006/21/EC.” European Commission.
ICOLD (International Commission on Large Dams). 2001. “Tailings Dams, Risk of Dangerous Occurrences,
Lessons Learnt from Practical Experiences.” Bulletin 121.
Lavoie, Judith. 2017. “British Columbians Saddled With $40 Million Clean-Up Bill as Imperial Metals Escapes
Criminal Charges.” The Narwhal, March 28, 2017 - 18:36.
MAC (The Mining Association of Canada). 2017. “A Guide to the Management of Tailings Facilities, Third
Edition.” Version date: October 2017
Rico, M., G. Benito, A.R. Salgueiro, A. D´ıez-Herrero, H.G. Pereira. 2008. “Reported tailings dam failures, A
review of the European incidents in the worldwide context.” Journal of Hazardous Materials 152
ResearchGate has not been able to resolve any citations for this publication.
Full-text available
This is the third in a series of independent research papers attempting to improve the quality of descriptive data and analysis of tailings facility failures globally focusing on the relative occurrence, severity and root causes of these failures. This paper updates previously published failures data through 2010 with both additional data pre-2010 and additional data 2010–2015. All three papers have explored the connection between high public consequence failure trends and mining economics trends especially grade, costs to produce and price. This work, the third paper, looks more deeply at that connection through several autopsies of the dysfunctional economics of the period 2000–2010 in which the greatest and longest price increase in recorded history co-occurred across all commodities, a phenomenon sometimes called a supercycle. That high severity failures reached all-time highs in the same decade as prices rose to highs, unprecedented since 1916, challenges many fundamental beliefs and assumptions that have governed modern mining operations, investment decisions, and regulation. It is from waste management in mining, a non-revenue producing cost incurring part of every operation, that virtually all severe environmental and community damages arise. These damages are now more frequently at a scale and of a nature that is non-remediable and beyond any possibility of clean up or reclamation. The authors have jointly undertaken this work in the public interest without funding from the mining industry, regulators, non-governmental organizations, or from any other source.
Full-text available
A detailed search and re-evaluation of the known historical cases of tailings dam failure was carried out. A corpus of 147 cases of worldwide tailings dam disasters, from which 26 located in Europe, was compiled in a database. This contains six sections, including dam location, its physical and constructive characteristics, actual and putative failure cause, sludge hydrodynamics, socio-economical consequences and environmental impacts. Europe ranks in second place in reported accidents (18%), more than one third of them in dams 10-20 m high. In Europe, the most common cause of failure is related to unusual rain, whereas there is a lack of occurrences associated with seismic liquefaction, which is the second cause of tailings dam breakage elsewhere in the world. Moreover, over 90% of incidents occurred in active mines, and only 10% refer to abandoned ponds. The results reached by this preliminary analysis show an urgent need for EU regulations regarding technical standards of tailings disposal.
The Risk, Public Liability, & Economics of Tailings Storage Facility Failures
  • Lindsay Bowker
  • Newland
  • M David
  • Chambers
Bowker, Lindsay Newland and David M Chambers. 2015. "The Risk, Public Liability, & Economics of Tailings Storage Facility Failures." Northern Latitudes Mining Reclamation Workshop.(data updated to 2018).
Long Term Risks of Tailings Dam Failure
  • David M Chambers
  • Bretwood Higman
Chambers, David M. and Bretwood Higman. 2011. "Long Term Risks of Tailings Dam Failure.", October, 2011.
Tailings Dams, Risk of Dangerous Occurrences, Lessons Learnt from Practical Experiences
ICOLD (International Commission on Large Dams). 2001. "Tailings Dams, Risk of Dangerous Occurrences, Lessons Learnt from Practical Experiences." Bulletin 121.
British Columbians Saddled With $40 Million Clean-Up Bill as Imperial Metals Escapes Criminal Charges
  • Judith Lavoie
Lavoie, Judith. 2017. "British Columbians Saddled With $40 Million Clean-Up Bill as Imperial Metals Escapes Criminal Charges." The Narwhal, March 28, 2017 -18:36.