My Pray are with that families in Brazilian. This is a poor tailing management. Miner has to rethink.

It's a pity and unfortunate that waste that we have thrown can come back and claim our lives. May the almighty God prevail on the Brazilian families.Our hearts and minds are with the families who lost their loved ones. This should not have happened given the experience that BHP and Vale have in building tailings dams. I detailed investigation should be instituted immediately and must seek to establish the underlying causes to prevent a reoccurrence.Thank you for sharing our prayers is with the families and the people at the company.

Failures like this occur multiple times a year worldwide. They are possibly the biggest argument for the anti mining crowd but that does not excuse anything. When are we going to learn how to prevent them? The recent failure in Canada was, apparently, a result of a subtle interpretation of data.

It’s truly a sad day for the mining industry. Our prayers are with the families in Brazil especially so close to the festive season. Please keep us posted would love to know the outcome of this investigation.

You can find the latest update from today here:http://bit.ly/1NYIowW

Why was there a tailings dam located above housing? That is unconscionable. Either the dam was built above an existing village or someone let squatters build below the dam. I've seen pictures of high dams above Chinese villages and who knows where else it happens. These are bombs waiting to explode. The only allowable TMF should be either dry stacking or cemented fines in those locations.

The loss of life is such sad news and such a poor reflection on our industry. Our hearts go out to the families of the victims and the impacts on the surrounding communities. Unfortunately, this lack of stewardship seems to go on after each tragedy and we seem to do nothing more than support the NGO's predictions that yet another xx failures will occur in the future. After Mt Polley, it seems that the industry should have agreed that there can be no more failures; which are preventable with proper engineering and operation. The means and methods are available to prevent these failures and the loss of life, the issue just needs to be taken seriously to implement those methods.

http://www.nzherald.co.nz/business/news/article.cfm?c_id=3&objectid=11543354

the local prosecutor has indicated that negligent monitoring was a contributing factor.

Every accident has a beginning in a triggering event. So that there is an accident, put layers of protection to reduce the chance of the accident. Risk management has the exactly pillars: knowledge and risk assessment, control of risks through protective barriers and finally the monitoring of risks. It is not known exactly what caused the disaster but it certainly has to do with risk monitoring. The management was not well performed. Only an independent investigation can promote learning from what happened. One more child was found died today (5 years old).

It is so sad that the mining industry makes great gains in safety and then an event like this ruins it all. When an event like Mt Polly occurs it should trigger everyone else with tailings to re examine the management of tailings in their operations. So many times even in injuries we hear were alright it cannot happen here, Assessment of risk and a working risk program is so essential to every mining operation. Most important is dealing with the risk after it has been identified and part of the program is ensuring the risks identified are completed and signed off in a timely matter, Management at a senior level must audit to ensure the program is working.

It is indeed sad. Tailing dams and waste dumps are probably the most neglected areas of mining activities. The concept that mining is a dangerous activity has worked well in improving the design and monitoring of the core mine, but the waste management activity still needs improvement. Contract working probably is working against this, as waste re-handling, stabilisation and continuous monitoring impact the bottom line.

I'm wondering when dry stacking will become required for tailings storage worldwide but shudder at the cost. Then again, under many laws if you cannot store the waste safely and without a risk to the environment a deposit is not ore and these incidents keep pointing in that direction. In many locations the water is valuable enough to justify dry stacking for economic reasons. Would high rainfall regions mandate dry stacking just for structural integrity? That would only leave the intermediate precipitation zones for possible exemption, and that is where most of these incidents seem to occur.

Such disaster is the result of a weak or corrupted regulatory body. Knowing the safety body in Brazil I am sure this is associated to corrupted causes. Cases of relaxed inspection and certification corrupted process during construction are spread all over Brazil. E.g. Bridges falling in the middle of the high dense urban cities, craters walling neighbourhoods in subways constructions, landslides in high tourist locations in every summer, cheap construction materials being used instead etc these are natural disaster caused by the man impunity. Tragedies and urban issues are common however when it happens to a large private company like Samarco seem something went very wrong during design and I don't believe it was engineering simply mistake.

Our prayers for the people who died caused by this accident...why was the dam built over the village? Was the village already there or was it built after the mine? Either way it was a bad design, villages should never be below any dam...accidents happen, unfortunately...anyone remembers in the '70's when a huge boulder fell from the mountain in the early hours of the morning in the dam below making it overflow flooding the village below killing almost everybody...common sense and past experiences dictate that people should live at least within 15 miles radius in case of accidents natural or not.

Which one was built first?

That's what I was trying to find out.

TO ACCEPT OR NOT, THAT IS THE QUESTION

The tragedy in Minas Gerais, with the rupture of dams, raises an additional question commented on in the media, such as the reliability of protective barriers. The management of the barriers is important, but there is something that arises before this matter: the tolerated level of risk. Risk is related to the frequency expected that something may occur in the future. There is another question: on whose behalf you are accepting the risk. A person who spends his goods risking your own luck, bet against its failure or success. But who bets on behalf of others, needs approval before betting. This is how we operate industrial investments. Entrepreneurs play with risks. Nothing is gained if without risk. Zero risk is zero gain. So they bet. When the loss is just financial, the loser can go bankrupt and employees lose their jobs. But when the loss of human life involves the matter is more complex. How much is a human life? Much has been discussed that in recent decade. What is paid compensation for victims after an industrial accident or plane crash, for example, it is usually low. But actually varies and takes forever to receive any compensation. What is the acceptable probability of someone coming to die as a result of an industrial accident? Who should answer this question? Several Brazilian states have rules or guidelines that stipulate the individual and societal risks - those for multiple fatalities - which may be accepted. This is known as Risk Matrix. This is to approve or reject a project. Companies can use their own rules, provided they are not more tolerant of risk than current legislation. What we bring to the discussion in this comment, we give to the following question:

Um particular risk, for example, a person died in an industrial accident outside the boundaries of the property (i.e. a community person), is accepted with the same level of probability in all Brazilian states?

Industries Oil & Gas, Petrochemical, Mining, Steel, Pulp and Paper, for example, must have the same acceptable level of probability, anywhere? How is that in Brazil today?

The difference between 1 / 10,000 and 1 / 1,000,000 in the probability of fatal requires at least one additional barrier robust, reliably ensured by periodic scheduled inspections and tests. To reach 1 / 10,000 is not easy. A procedure, alarms and inspections are not enough. Who needs to operate with a chance of 1 / 1000,000 to suffer third-party inspections (external and independent). A few months after the disaster of one offshore platform in Mexico Golf was published in a newspaper in Texas: in ten unscheduled inspection visits (surprise) the federal government on oil platforms, only one was actually being made. The barrier is gone and the risk rose. In conclusion, we leave here to reflect the issue involving the YES and NO to accept a particular industrial risk. The breaking of a dam, or rather two, in Minas Gerais should be a very rare event. But by the way the record shows that it has not been uncommon. What were the weaknesses? Barriers and / or likelihood accept years ago? Following the accident at Nightclub Kiss (in South of Brazil, 242 fatalities) many standards were proposed. Certainly could have contributed to reduce the likelihood of the type of risk in question. But there was influence of stakeholders and much fell apart. Not learned. Risk reduced but not known to what level and whether it is acceptable or not? Were more political and less technical decisions that defined the new legislation. By the way, what is the risk accepted for the same accident Nightclub Kiss on the outskirts of Manaus and Rio Branco (north of Brazil, near jungle)? Hopefully we are learning from the tragedy of dams in Minas Gerais occurs and include something about the level of tolerable risk for this type of venture.

Brazil Industry don't understand what is new Technology for Waste (Domestically and Industrial) Tretment. You don't need barrage or dick you can separate Solid Waste from Liquid. Solid you are usingfor producing Bio Energy and Water Treatments.

Please see my new project introducing in Santa Catarina "IlhaSâo Francisco" Steel Plant Arcelor Mittal (old Usinor France) Named 3vega do Sul.

Brazil has most modern technology for Treatment Red Mud from Alumina Refinery which I'm introducing in Alumina Refinery CBA group Votorantim in which I'm working from 1978 to 1996. After my come back in France any Engineer working in CBA doesn’t understand this new technology - Absurd.

Regardless of tailing treatment technology, villages must not be built close to dams, accidents happen, natural or not. But again we are dealing with a South American environment where corruption is wide spread.

In recent decades some jurisdictions (including British Columbia, Canada) have engaged in land use planning, expending considerable time and capital deciding what kinds of activities can be carried on over particular landscapes.

Some tracts are dedicated to preservation/parks; others may be designated as appropriate for forestry, mining, tourism, agricultural or other uses.

When studying which lands might be appropriate for mining mineral potential is clearly a consideration - no point in planning for possible mines where the likelihood of finding an ore deposit is limited!

What is never considered when making these kinds of land use planning determinations is the suitability of landscapes for waste rock storage facilities - which are essential if a mine is to be built.

It seems to me that identifying suitable areas for waste rock storage facilities - and preserving them for potential mining use as such - is a necessary part of responsible land use planning in areas of moderate to high mineral potential.

Around 250 million USD is the initial value to be paid by Samarco. The environmental impact has extended over 400 km towards sea causing contamination of Doce River liquidating fishermen activities and contaminating the source of potable water for the communities that are established nearby the rivers. Potential impact on the reefs 300 Km south Abrolhos (Bahia). Several interesting facts like the trench was recently inspected and certified by a third body, operating at 90% of its capacity at the time of the event and a revamp was being developed to expand the capacity, some seismic activity at 2.2 to 2.5 richter and obviously NO effective emergency response plan in place. At the moment the third downstream trench at Germano has been detected with a significant crack however seems stable. Indigenous communities are also affected 200 Km downstream.

In the last 20 years it has been recorded at least 4 similar smaller events in the region with a few number of fatalities.

Seismic events of 2.2-2.5 are relatively low; do they reflect causality …Or the collapse event itself?

Dropping a laptop on the floor from a typical table height would result in a magnitude 1.0 seismic event IIRC. Realizing that was a personal eye-opener itself derived from nuclear weapons works. I would point out that cira 2.0 events are, to use Shakespearian language, farts in a windstorm. Dam failures sometimes create seismic signatures that are rarely strong. The event takes some time, mitigating a strong signal. Anyone recording vibrations from a failure is probably measuring the result rather than the cause. That said, it is imperative that dams be designed for likely events and any legislation that I have ever worked with reflects that. I can't comment about Brazil.

This light seismic activity was detected previously in the event. This is under investigation and no causality has been confirmed. As we all know Brazil is blessed to be a place with great weather and privileged great location with very low negative nature activities (probably only strong rainstorms). Structures normally are design for minimum seismic activity. Ageing plus a heavier flow of water might be affecting installations all over Brazil. Most facilities have more than 30 years (since intense industrial era happened around 60/70s). Wearing out phase may be spread over several locations and life extension or replacement might be required.

My point exactly! 🙂

Thanks for clarifying the timing. And yes, properly designed dams take into consideration not just likely events - but unlikely, rare, ones too!

We are focusing on a seismic event but there is another common cause that civil engineers describe as a piping failure. Water finds a route through the dam and starts to move particulates until it becomes a hole that progressively worsens. It is usually a design or construction flaw and deadly as to the results.

The recent Mt. Polley incident was another type of failure, that of the foundation itself. IIRC there have been a few power dams lost for the same reason.

It will be interesting to find out what caused this last one. But, will anyone learn from it?

Dams failing are commonly a combination of factors. An ageing structure would certainly give in at some point. Structural defects in the overall dam embankment would equally never stop huge tailings or mass of liquid from escaping and causing massive harm in their wake. A systematic trouble shooting /root cause analysis process would give more insights.