Samarco Executives May Face Homicide Charges For Deaths In Fundao Tailings Dam Failure

 It was reported on February 5th that Samarco executives may face homicide charges on the basis of victim autopsies and records seized by police.

We have gathered all of the findings from the autopsy reports, in which we determined that the crime of murder had been committed,” said Rodrigo Bustamante, who has been heading up the investigation for the state’s civil police

What is suggested in this report is that the evidence supporting criminal charges for murder  was based on (1) cause of death clearly attributable to the gigantic mudflow (2) that the risks  of failure and its consequence were clearly known and/or  forseeable and that  (3)  not  taking recommended steps to prevent failure .

As part of their criminal investigation, authorities carried out searches on the premises of the Samarco headquarters, in which they collected copies of emails and internal company messages in order to determine whether the company executives know about the impending risk of the dam breaking.

Independent experts warned two years ago that the jointly owned Samarco mine, which collapsed in southeastern Brazil killing 19 people, was not safe.


Most of those killed were workers at the mine working on a project preparatory to the merging of the closed Germano and the Fundao by removing the Silenha Dike separating the two .  That plan had not been authorized or approved though steps towards its implementation were underway.  The Silennha dike was one of the structures damaged during the failure.  Some of those may have been employees of the contractor retained by Samarco for this work.

The criminal investigation, presumably through new evidence gathered in the raid on Samarco’s record, may increase the amount of the already initiated $us5.1 billion damage claim.  It was not disclosed whether criminal charges other than murder would also be brought.  A separate lawsuit and investigation under Brazil’s Environmental Crimes Statute has been underway since right after the failure on November 5th.

Still another law suit was recently initiated by  the Federal Office in Linhares near the mouth of the Rio Doce on behalf of fisherman whose livlihoods have been indefinitely interrupted and impaired by the mud flow.

Criminal charges have also been filed against Herculano Mine exceutive for a tailings dam failure there in 2014.

A finding of criminal acts would most likely nullify all or most of the $60 million of the loss previously reported as insured.  Property & casualty insurance , which would include claims fied by homeowners, business owners, farmers and the two states involved where a cause is “an act of God”  would not respond to any claims resulting from criminal acts or fror forseeable and preventable.   Until recently, as usually happens following a mine catastrophe owners were suggesting that the final investigation would show the cause was two small earthquakes quite close to he site of failure.  Bowker Associates has reviewed that data and it appears that both were after the Fundao failure and possibly caused by it.  In recent comments Samarco, BHP and Vale have not referred to the two small tremors as a possible cause of failure.  That would be an unsustainable claim anyway as the dam should have been built to withstand a maximum credible event during its operation and into perpetuity and that is well above 4.5.  The two small quakes were 2.5 and under.

 Claims by victims families and all who suffered damages can still be pursued in civil court and by writing a notice of cliam directly to Samarco at its Corporate Headquarters. And of course, all claims are still be valid, regardless of insurance coverage  but there would be no insurance to respond and it would be that much harder for victims to prepare, file and manage their claims.

Minas Gerais has not required Samarco to set up and fund a claims management litigation support process for victims.  Bowker Associates is investigating whether it is possible to set up a miner funded claims management litigation support process for the victims likely to number in the thousands.  They have enumerated $R 1.2 billion in damages and losses to the two municipalities affected by the failure exclusive of te $US 5.1 billion in envionemntal damages and any payment to families and affected businesses.

O valor consta em relatório divulgado nesta quinta-feira (4), pela força-tarefa montada pelo governo de Minas para apurar prejuízos causados pela tragédia.) The value contained in a report released on Thursday (4), the task force set up by the government of Minas to determine damages caused by the tragedy.( O valor será cobrado da Samarco, que pertence à Vale e à BHP Billiton.) The amount will be charged  to Samarco, which belongs to Vale and BHP Billiton. (No total não estão incluídos danos ambientais e recursos que serão utilizados para o pagamento de indenização a famílias). This amount is nand does not include environmental damages or provision for the payment of compensation to families.

(Conforme o relatório, 320 mil pessoas foram atingidas pela tragédia, que já tem 17 mortes confirmadas.) According to the report, 320,000 people were affected by the tragedy, which already has 17 confirmed deaths. (Duas pessoas ainda estão desaparecidas. Two people are still missing.

“….According to the report, the production chain in the region recorded losses to the private sector of R $ 540,466,816.00, according to information forwarded by municipalities.( As perdas foram por morte de animais, destruição de lavouras, pastagens, máquinas e construções). Losses were due to death of animals, destruction of crops, pastures, machinery and buildings. (Os prejuízos públicos totalizaram R$ 146.066 455,33, principalmente com a prestação de serviços como abastecimento de água, que ficou prejudicado com a lama no Rio Doce.) Public losses amounted to R $ 146,066 455.33, mainly to the provision of services such as water supply, which was damaged by the mud in Rio Doce. (Em relação à infraestrutura pública, a lama da Samarco consumiu R$ 513.755.631,00, com a destruição de estradas, postos de saúde, escolas, e comunidades, total ou parcialmente, como Bento Rodrigues e Paracatu de Baixo, em Mariana.) In relation to public infrastructure, the  Samarco mud flow caused R $ 513,755,631.00, in losses including the destruction of roads, health centers, schools, and communities, in whole or in part, as Bento Rodrigues and Paracatu Low in Mariana”

Samarco has claimed it relied entirely on qualified consultants with recognized expertise for the design and ongoing  management of the failed tailings dam specifically naming Dr. Joaquim Pimeta De Avila who has been a key witness in the police investigation.  They say they received no notice of imminent risk of failure and had no knowledge of any problems that elevated the risk of failure.

Samarco id not meet the Federal government demand for deposit $R2.1 billion of the $Us5.1 billion to provide immediate funding for emergency recovery claiming it has already spent$R2.3 billion in clean up. and is continuing to fulfill its recovery obligations.They also indicated they need more time to post any further large amounts in cash.

Contact: Lindsay Newland Bowker, Founder & Director Bowker Associates Science & Research In the Public Interest

Posted in BHP, Bowker Associates Science & Research In The Public Interest, Catatrophic Tailings Dam Failures, Causes Of Catastrophic Tailings Dam Failures, Fundao Talings Dam, Geoesteval, Germano Tailings Dam Failure, Linhares Civil Action Against Samarco, Samarco Murder Charges, Uncategorized | Leave a comment

1 million Cubic Meter Landslide From Ruins of Failed Fundao Dam


On January 27 the debris in the site of the former Fundao dam  shifted causing a 10 minute slide of 1 million cubic meters of material out of the site  and necessitating the evacuation of all workers. According to Paul Kiernan, WSJ, Samarco did not report the slide to authorities. The Extraordinary Commission on Dams of Minas Gerais who visited the site on Januray 29th have stated that there is imminent risk of further failure of material from the Fundao site.

This incident is also cited in the Civil Action against Samarco filed on 2/2/2016 by the Federal Prsoecutors Office in Linhares on behalf of fisherman who have suffered and are suffering economic loss of indeterminate future impact.  I was unable to get a Bing Translation from this pdf but understand that all fishing had been suspended as is the annual custom during the spawning of certain important native species.  During the time of suspension fisherman are compensated for agreeing not to fish.  The original failure on 11/5/2015 occurred during this spawning period. It is not clear what impacts the failure had on the protected spawning species or how long I will be before fishing can resume. com .  The public civil action against Samarco on behalf of fisherman cites the release on 1/27/2016 as 960,000 cubic meters. ( less that the 1 million threshold for classification as a “very Serious Failure”  in the Bowker Chambers 2015 classification of severity.

fish killed by mud samarco.png

Fish Killed By Samarco Dam Failure

“Members of the Special Commission on Dams MGSL (Legislative Assembly of Minas Gerais) were to visit the Germano mine in Mariana, in the central region of the state, on Friday (29).( A estrutura pertencente à Samarco continua em pé, mas apresentou trincas após o rompimento de Fundão , em novembro do ano passado.) The structure belonging to Samarco is still standing, but showed cracks after the breakup of Fundão, in November last year. (Agora, os parlamentares querem verificar se o novo vazamento ocorrido na quarta-feira (27) no complexo das barragens não afetou o local.) Now, lawmakers want to make sure that the new leak occurred on Wednesday (27) in the complex of dams did not affect the site”(link to source in original language)

This is only the 36th recorded event in world history of a tailings dam release of 1 million cubic meters or more, the definition set in Bowker Chambers 2015 for  “very serious failure”.   That global study of trends in the severity of  tailings  dam failures  1910-2010 identified 29 authoritatively documented TSF ( Tailings Storage Facility) failures.  Since then a 1937 previously un documented catastrophic failure in Mexico has come to light and we had authoritatively documented 5 new “very serious” failures from 1/1/2010 to 12/31/2015 (including the Samarco on November 5th, the largest ever recorded in world history).

The January 27th post failure release of and additional 1 million cubic meters from the site brings the count of events for the decade ending  on the date of the “latest very serious failure” at Samarco’s  mine to 10 as compared with 7 for the decade ending 12/31/2009 as reported in Bowker Chambers 2015.

Although there are several events in recorded history of multiple very serious failures at the same mine and a few repeated at same TSF with a time interval of a few years, this is the first recorded  time in history 2nd major failure at the same TSF immediately following a first primary very significant release.

According to company statements following the 2nd “very serious failure” on Wedesday January 27th, there are 20 million cubic meters more at the obviously unsecured, usatble  site of the former dam.  There we no statements about  steps being taken to prevent the release of more of this 20 million cubic meters of material remaining in the site of the former Fundao dam.

After the first release of the  former dam on November 5th there was no evidence of any remaining structural component of the Fundao which was put on line c 2008-2010. ( see photo below). In statements after that failure Samrco eventually reported that structural assessment of the other two dams had been undertaken and that both were below the required 1.5 level.  They made no mention of any stability assessment at the failed Fundao site where this second release occurred  on January 27 or of any work planned there  to assess or stabilize any material in the site.  They did not describe or characterize the  material at the site of the former Fundao.

photo of two dams..

Fundao Dam Former Site Immediately After Failure

In their December 2015 report updating site conditions, repair and relief work no mention at all is made of the Fundao  site, only of the damaged Silenha dike and the damaged Santorem.  That report details the “state of the art” surveillance system  and use of drones to monitor stability and safety at the dam sites and makes no mention of the presence of 20 million cubic meters of material within the former  site of the Fundao dam.

This recurrence points to an apparent gap in the overall statutory and regulatory structure presently applicable to stability and safety at the site . There is no police power to force an independent stability assessment and an independent expert opinion prioritizing actions to prevent further damages at a level 30 times greater in magnitude well above the minimum level for “catastrophic”  potential impacts in the  Bowker Chambers 2015 severity classification .  The public continues to remain at the mercy of Samarco’s reassurances that priority in their decisions making post failure is to prevent further downstream damage.

The New Zealand parliament found itself in this same situation in 1996 when it became clear that the miner was not taking proper action to prevent a complete failure of the tailings dam at Golden Cross.  The flaw in the dam was known at acquisition by the miner and a focus of community demands for its proper indepedendent inspection and repair.  The miner, not very experienced and trying to build a global presence through acquisitions, had under estimated the cost and scope of work necessary to repair the known flaw.  When the inevitable and expected landslide occurred without breaching the dam the parliament met to deliberate whether they had given themselves sufficient power to intervene and realized they had not. In that case fortunately the miners excessive debt and other financial woes came to the rescue of the public interest and court proceedings provided $53 million out of assets towards the damages at the dam. which was successfully repaired and closed without a rupture.

This gap exists in almost all mining statutes and could be cured through creation of independent expert panels funded by applicant miners and those licensed via the overall regulatory framework for mining,  accountable to neither  regulator nor miner,  with clear accountability to investigate and direct action .

It is important to note that Samarco did have an Internal Tailings Review Panel ( membership and details unknown) which functioned as it should in red flagging  emerging stability and safety issues and offering alternative.  Where the ITRP adivce didn’t fit with Samarco’s greater commitment to maintain production costs at a certain level, the panel was ignored. This in essence is the testimony of Dr. Avila to police investigating a possible Environmental Crimes action against Samarco.

As that investigation progresses, there is still no way under existing law to compel independent assessment and action at Samarco’s expense of the actual security and stability of the former Fundao site and the damaged Dike and Santorem.


Town Of Mariana Where Samarco’s Failed Mine Located


We will be updating this post to bring in links to the referenced Golden Cross parallel, to Samarco’s previous statements and to the confirmation of  Samarco’s independent expert panel.  Most of this is already provided in other posts on the Samarco at this site.  Not all of our commentary and analysis is via this site.  Most, in fact is in a running e-roundtable with a multi disciplinary global network of experts, press, other researchers and other pubic interest groups. It is from this “e roundtable” that we will bring in the links.

As always, please contact me directly at with any corrections, clarifications or further information related to this post.

February 2 2016 Stonington Maine

Lindsay Newland Bowker, CPCU, ARM, Environmental Risk Manager

Founder & Director Bowker Associates Science & Research In The Public Interest










We will add to and update this post with refernce

Posted in alegria mine, Analysis TSF Failures, Bowker Associates Science & Research In The Public Interest, Brazil 's High Grade Iron Ores, Causes Of Catastrophic Tailings Dam Failures, corporatocracy, Environmental Risk Management, Fundao Talings Dam, Germano Tailings Dam Failure, Height Limits of Earthen Dams, Highly Valued Natural Resources, Lindsay Newland Bowker, Linhares Civil Action Against Samarco, Measuring Magnitude of Consequence TSF Failures, Metallic Mining Risk Management, Mine Feasibility, Mine Risk Management, Mining Economics, Mining Environmental Crimes, mining environmental risk management, Mining Financial Feasibility, Samarco falha de barragem de rejeitos, Samarco investigação de crimes ambientais, Uncategorized | Leave a comment

TASEKO TANKING: ANOTHER SCHOLZ “Mining Metric Original” Accrues Ever More Potential Public Liability While It Struggles With Too Much Debt And Too Little Cash Flow

 With copper prices dropping below $2 per pound, Taseko may just be trying to keep afloat during 2016. It has an estimated $65 million USD in cash at the end of 2015, and requires approximately $2.25 per pound copper to break even as a company. At current copper prices, Gibraltar’s production is very marginally profitable after factoring in off-property costs.

There is some hope that copper prices may rebound somewhat, as many analysts believe that the current copper price does not accurately reflect the supply/demand picture. However, there is quite a bit of uncertainty around copper prices, and Taseko needs to carefully weigh the need to bolster its liquidity versus increasing its interest costs too much when refinancing its Red Kite loan (and potentially taking on more debt).  Seeking Alpha 2016

Board member George Ireland, a highly regarded and well informed mining investor  recently dumped over 7 million shares at $us0.30/share.

As of January 22, 2016 Taseko had a market cap of only $us98 million. It has $32 million due in May from the Curis  transaction financed at 11%.  Copper prices have continued to decline since Taseko last discussed refinancing at a lower rate. “Interest costs are approximately $19 million per year including the estimated interest cost from the new secured debt.

This results in estimated cash flow in 2016 ranging from approximately negative $45 million at $1.75 copper to positive $39 million at $2.75 copper. These estimates incorporate the effect of the Canadian dollar exchange rate varying in conjunction with copper prices.

Continuing a general alert about Taseko throughout the investor community  Taseko was further  downgraded by Standard and Poors from a B- to a CCC+.

“The downgrade reflects our view that Taseko’s capital structure appears unsustainable due to very high leverage and interest costs, although we do not envision a specific default scenario at this point,” said Standard & Poor’s credit analyst Jarrett Bilous. S&P expect Taseko’s high ongoing debt servicing obligations and maintenance capital expenditures will result in cash flow deficits that gradually weaken the company’s liquidity position…

The agency estimates the company has sufficient cash to fund its operations beyond the next 12 months, with an additional cushion from its recently announced secured credit facility. “However, we believe the company’s capital structure is likely unsustainable in the long term, barring a pronounced and sustained rebound in copper prices. As a result, we view the company as vulnerable and dependent on favorable business, financial, and economic conditions to meet its financial commitments, which is consistent with our criteria for issuers we rate ‘CCC+’.” Taseko derives all production from its 75%-owned Gibraltar mine, which exposes the company to copper market fluctuations and unexpected production disruptions that can impair operating results, as witnessed in late 2014 to early 2015

All of this and the economic history of this mine, an original Scholtz acquisition setting out to prove that very low grade ores can be profitably mined,   was known and knowable at the time B.C. Ministry of Mines recently approved the highly controversial supernatant discharge.   The Gibraltar was originally permitted as a zero discharge facility.  In 2008 Taseko applied for and received a permit for discharge to the Fraser.  The latest, recently approved  doubled the allowed discharge.  Taseko threatened they would have to close the mine if the discharge were not approved. 

This week B.C. Ministry of Mines announced “relief”  for the B.C.’s  troubled mines essentially through more debt.  Miners on shaky ground financially will pay 12% and those more stable 8% to defer  hydro payments for two years.  Of course energy costs have been a key factor in increasing mine unit costs of production but  the problem is so much bigger than that and it is that bigger problem that B.C. Ministry of Mines and all other regulatory agencies need to take into account in reassessing  the present and future place of their mineralized assets in the global market place.  Two years is not going to bring any good news to B.C.s existing permit holders or to mining affected communities in B.C.  This is just ducking the problem , deferring the ultimate consequence to lost jobs and possibly accepting a loss on debt added where debt is already a huge part of the financial risk that will translate to public liability.

The economics of  a mine and its possible implications for accrual of unfunded unfundable public liability are simply not taken into account and rarely,  if ever, addressed in public advocacy.  On both sides the envirnonmetal security threats  are considered strictly in terms of the volume and quality of the sought release and the flow and quality of the receiving public waters, in this case the Fraser River. The liklelihood and implications of a sudden standby are never specifically reviewed  and taken into account by experts in mine risk finance or mine valuation.  The conditions promptng the discharge application, a dramatic increase in production  pushing beyond the capacity of the exiting TSF, its drainage systems and the associated water management infrastructure to handle the projected volume of production is never explicitly evaluated from the point of view of the “increased social premium” in the event of failure or public costs which will be incurred to avert failure should the miner not perform on its obligations ( e.g. Golden Cross in New Zealand).

This is the story not told or even acknowledged by the Mt Polley Dam Committee.  This is the story of the Gold Ridge in the Solomon Islands hovering on the verge of collapse. This the story of Samarco. This is the story of many superfund sites including the $1 billion public liability of the Yellowknife. and the now abandoned Wolverine.

“Although there are alternatives to management of increased supernatant levels a substantial  increase of mine throughput requires, law does not require a consideration of such alternatives all of which would add both to cost and to ongoing costs to produce

At a minimum, it would seem that wise public policy needs to insist on a proof of “no likely increase in the social premium” by at least showing economic feasibility in a global context through the stated increased throughput stage as well as demonstrating the  the pre existing full capacity to manage the additional wastes and minewaters”  Bowker Associates Science & Research In The Public Interest 2016



The Gibraltar mine attained a throughput of 100,000 tpd,  the lower range of throughput envisioned by the Pebble mine. ( 100 Ktpd). With only one 4 year period in stand by (1997-2004) the very low grade Gibralter mine has operated continuously  since 1971, 44 years, approximately half the projected life of the Pebble.  It has s a center line conventional slurry deposition tailings facility that is now 452 feet ( 140 m) high with a foot print of 546 hectares, some 6 miles across.  (will add source and re verify these figures).  It’s hazard ranking is “extreme”, ie in the event of failure lves would be lost and the  damages would be non recoverable according to the 2014 Klohn Crippen dam inspection report.. Mt Polley at failure was only  50 m high with a much smaller foot print  not as well engineered and constructed as the present Gibraltar TSF.  From the outset  the Gibraltar has had a sand cyclone system which is still considered best available technology  for slurry deposition.

The waste from the mine has filled three valleys  generated mostly at throughput 1972 to 1997 that had averaged only 37Ktpd at an average head grade of 0.313 cu.  So we have yet to see what sustained production at 100ktpd and to an even lower grade (.20 cu  the cut off grade at Gibralter) actually means to the surrounding potentially receiving environment. The review of mine expansions never considers whether the technology that presently exists can keep these mines profitably  producing over their very long lives without more and more accommodation on the public side and higher and higher levels of environmental and public risk.

We will be adding more to this post, one of a series we hope to do on Scholtz vetted mines and the actual economic and environmental performance of very low grade mines in history.

Every economic failure of a large mine translates to a “social premium” that comes right off the top of GDP.  Treating these losses as “insured”  by simply leaving the often non remediable damages does not change that.  The damages themselves impair present and future GDP. They have a very long “tail”.

Lindsay Newland Bowker, CPCU ARM, Environmental Risk Manager

Director, Bowker Associates Science & Research In The Public Interest

Stonington Maine







Posted in B.C. Hydropower Payment Deferral For Troubled Mines, Bowker Associates Science & Research In The Public Interest, Canadian Mine Risk & Loss Profile, Canadian Mining, Causes Of Catastrophic Tailings Dam Failures, Environmental Risk Management, George Ireland, Gibraltar Mine, Global Capital Squeeze In Mining, global cash flow crunch, global copper market outlook, Highly Valued Natural Resources, Imperial Metals, Lindsay Newland Bowker, Measuring Magnitude of Consequence TSF Failures, Metallic Mining, Metallic Mining Risk Management, Metals Price Forcasting, Mine Feasibility, Mining Economics, mining environmental risk management, Mining Financial Feasibility, Mt. Polley, Mt. Polley Tailings Dam Failure Impacts, politics of mining, polluter pays advocacy, Social Premium of Metallic Mining, Taseko, Uncategorized | Leave a comment

Herculano Mine Partners Indicted on First Degree Murder Charges For Worker Deaths In September 2014 Tailings Dam Failure

The indictment, announced December 16, 2015 is for  continuing to place tailings in a dam that was impaired , had already reached its capacity, and no longer was licensed to receive tailings. Findings also reference failure to notify authorities of the failure and providing false information to officials.
 herculao dam failure_
Reuters Photo Immediately After  Failure
The new  B4 tailings dam was to receive all tailings waste from a mine expansion as of 2010 but developed problems in 2014.which precluded its continued use. Apparently  without authorization  or technical independent review the company started using the compromised B1 again.  ( The  Bing Translation of the above news source refers to construction of a series of 4 holding bays within the unlicensed B1) An  official  government document rescinding  Herculano’s authority to mine,  refers to google earth photos showing unauthorized construction to “increase the height of the B1”, the phrase produced by the web translator.
The hastily modified B1 tailings dam  failed due to saturation caused by inadequate drainage according to a technical report prepared by the Institute of Criminology.
The finding was that Herculano executives were fully aware of the dlminished capacity of the dam and the risks and of  the consequences of failure and nevertheless assumed the risk .  Under Brazilian law that constitutes criminal intent ( according to the awkward Bing Translation).
We are not well steeped in Brazilian Law and  any evaluation based on a Bing translation and not in properly translated actual technical and legal documents is inherently limited . This sounds, though,  very much in line with common law as  it applies and governs most court cases in the US and Canada. Unless modified by statute ( there have been some fiddles in Canadian Law for mining) strict liability” applies to all inherently dangerous activity.  The activity may not be prohibited by law or regulation or  explicitly prohibited by the  terms of a permit but any damages accruing from its undertaking are “negligence per se”. There is no defense in tort.  The fact of the ultra hazardous activity and the fact of the resulting damage constitute.a legal accountability for all in defective product torts.
That this is a criminal indictment implies that the  ultra hazardous activity was undertaken in a reckless manner and/or that the decision itself to use the dam in such a condition was de facto reckless. Strict liability in the context of criminal charges does not require a proof that that any intent existed with respect to the consequence ( in this case, the death of the  B1 workers).   The description of charges and findings suggests that what has been applied in Brazilian Law is very similar to ,if not exactly in conformance with, a criminal strict liability charge.
 herculano dam break photo 2
 Reuters Photo 2010 Immediately After B1 Failure
Pattern of Pushing Tailings Dams  Beyond Safe Capacity & Use Very Clear In History of Catastrophic Dam Failures
Bowker Chambers 2015 ( The Risk, Economics and Public Liability of Tailings Storage Facility Failures pointed to the pattern of production needs and aims trumping tailings dam safety as a recurring and significant theme in the history of catastrophic tailings dam failures 1910-2010.  Several modern catastrophe’s including Samarco,  Mt Polley and this failure  occur as a result of aggressive mine expansion plans that do not have accompanying adequate waste management plans or capacity.  Herculano Mineracao Ltd. had received licenses for a major expansion in 2013.predicated on the capacity and future expansion of the B4.

“In fact this is the pattern we see on close examination of Very Serious and Serious failures; older TSFs with smaller footprints are pushed to unplanned heights to accommodate additional production that was not anticipated when the tailings dams were originally designed and the permits originally  issued.. Capital markets and investors don’t finance clean ups. They finance production that is profitable. Smaller companies operate on tighter margins within the same overall metric affecting all miners but are less able to take advantage of and finance optimizations or achieve economies of scale that will keep production costs low enough to maintain a specific mine site as economically feasible.

Our sense of the data, and the case histories we have looked to for a deeper understanding of the data, is that “mining economics” plays  a significant role in TSF failures. It is important in permitting, and in the checks and balances built into the regulatory process over the life of a TSF, to look beyond “mechanisms of failure” to the  fundamental financials of the miner, the mine, and mega trends that shape decisions and realities at the level of miner and individual mine.​”

​The November 5, 2015 failure of the Fundao  at Samarco’s  Minas Gerais mine in the Alegria Complex also  fits this pattern.  They elected to go forward with a major expansion without adequate TSF capacity and without any plan for achieving this capacity  They were fully aware from a failure analysis that a failure of the Fundao would wipe out Bento Rodriquez in a matter of minutes and elected to take the risk with no peer review  based on an undisclosed mathematical model indicating a low probability of failure..( This according to Jack Caldwell and a recent source in Brazil who had been consulting engineer on the dams through 2012)
Technical Details on The Herculnao & Most Catastrophic Mine Failures Hard to Come By
Jack Caldwell first reported this tailings dam failure  of September 20, 2014   at his now   silenced and completely obliterated   mining blog,” I think”. At the time  neither Jack nor any of his 5,000 regulars and handful of commenters myself included, could find any data at all on the failure.  It took a year to turn up in WISE as part of their compilation and the details needed for the Bowker Chambers 2015 recompilation of WISE/ICOLD data elements   and for meaningful further statistical analysis are still sparse: design dam height and slope, dam construction, year paced in service, design capacity, height at failure , run out and release all undocumented even after exhaustive and frequent searches in Portuguese and in English.
Most of these critical technical elements are also still not available on the Samarco tailings dams and its use of them .  The Germano Tailings Dam was supposedly closed in 2009 and the Santorem used mostly for water storage on top of some 12 million cubic meters of previously deposited tailings.  The Fundao, placed in service in 2009 was not capable of holding all the waste to be generated by the massive expansion Samarco planned nor was there adequate land space within the mine foot print to accommodate additional capacity but the expanded production nevertheless went ahead .   Over the life of the Fundao, 90 m high at failure, and an un buttressed upstream construction, the rate of raise had average 15. meters per year: pushing capacity by anyone’s reasonable definition.
Our rough estimate based on BHP’s SEC 20 filings to the Securities and Exchange Commission is that closer to 90 million cubic meters of wet tailings were produced since 2009. We can’t swear by our estimate yet and continue to polish it  but it seems very very clear far more than 55 million cubic meters in wet tailings was produced over the llfe of the Fundao.  Additionally we know now that Vale contributed about 2 million cubic meters per year to the Fundao. Where did all these wet tailings go?
Scope Of  Other  Damages At Closed  Herculano Mine
In December 2014 government completed a preliminary assessment of the scope of environmental damages caused by the B1 failure and negotiated financial responsibility agreement with Herculano Mineracoa Ltd for clean up and restitution.  An escrow of  was established  for work in 2015 in exchange for lifting the freeze on all Herculano assets.   Recovery is estimated to take 10 years.

The environmental damage caused by the accident at the dam Herculaneum Mining in Itabirito, Central region of Minas Gerais, is at least R $ 30 million. (Para garantir que todas as medidas de reparo e compensação sejam implementadas, o Ministério Público (MP) e a empresa firmaram um acordo no início deste mês e o valor, que já foi depositado em juízo, deve ser gasto em 2015. Em troca, a Justiça liberou os bens da Herculano e dos sócios da mineradora que estavam bloqueados.) To ensure that all repair and compensatory measures are implemented, the Public Ministry (MP) and the company signed an agreement earlier this month and the amount that has been deposited in escrow, should be spent in 2015. In return, Justice released the goods of Herculaneum and members of mining that were blocked.

(“Pode ser que o prejuízo seja ainda maior.) “It may be that the damage is even greater. (O que vai determinar a exata extensão dos danos é o laudo que está sendo feito.) What will determine the exact extent of the damage is the report that is being done. (Ele vai apontar, ainda, quais são as medidas necessárias a serem tomadas para recuperação da área”, explica o coordenador do Centro Operacional do Meio Ambiente (Caoma) do MP, Carlos Eduardo Ferreira Pinto). He will point out, though, what are the necessary steps to be taken for recovery of the area, “explains the coordinator of the Operational Centre of Environment (Caoma) MP, Carlos Eduardo Ferreira Pinto.”
 Bowker Associates has not been able to locate any text or summary of the referenced final report on damages and costs.  Herculano’s license to operate remains in suspension.
Tailings Management, Tailings Capacity & Processing Problems Long Term The Mine
 Compared to other Itabarites in Brazil generally and in MInas Gerais specifically, this mine had a  lower grade and characteristics which  challenged processing and resulted in higher processing costs.
Some details of this history are given in a technical report  on a magnetic separator which was introduced in 2010 to address some of the mines historic and persistent operations problems and associated environmental impacts.

In the historic mine, 40% of material extracted from the deposit was treated as waste and had an average iron content from 40 to 58% silica and about 30%, generating extremely high tailings volumes which the existing structures for containment themselves, were insufficient and caused major environmental impacts such as carrying of solid ravine on the edge, demanding – a big factor as to the monitoring of the dam, which was the limit of the quota and volume parameters, and so necessary licensing new areas and implementation of a new structure for disposal of waste produced.


This technical report also has a photo ( fig 3.9 pdf p 24) and some details on the dam: an upstream dam, 20 million cubic meter capacity ( in 2010), 60m high .  These are descriptor of a dam pushing the limits on  best knowledge, best guidance, best practice on upstream dam use.

The separator promised recovery of u to 78% of material which had historically been treated as waste  post concentrator. and therby better use and longer life  of tailings impoundments as well as lower overall production costs.

Interesting to note that the photo and focus on this 2010 report is of the failed  B1 whose license had already expired and whose full capacity had already been reached as is apparent in the photo.  The new dam, the B4, was supposed to be already in service but is not mentioned in this report on the magnetic separator.


The following is a web translation of the EIS and Enviornmental Damage Compensation on construction of the B4 which was to receive all tailings from the mine expansion totally replacing the B1.

The final mass of the dam has maximum height of 1,240 m, maximum height of 30m( e comprimento da crista superior de 360 m, sendo constituído de solos argilo-siltosos, 30m )and length of the upper crest of 360 m, consisting of silty-clay soils)compactados e protegidos por um sistema de drenagem interna (sistema extravasor do tipo )compressed and protected by an internal drainage system (overflow system of the type (galeria tubular, com diâmetro de 600 mm que irá subindo à medida que o maciço for sendo )tubular gallery with a diameter of 600 mm that will rise as the mass is being(alteado, atingindo em sua configuração final a cota de 1.240 m, em sua soleira. alteado)reaching its final configuration the height( believe this should be translated elevation) of 1,240 m, on his doorstep.( O sistema )The system(de drenagem interna é constituído de filtro vertical e um tapete drenante horizontal) internal drainage is constituted by vertical filter and a horizontal drainage mat(interligados e construídos com areia grossa e materiais de transição, sendo que este tapete) interconnected and constructed with coarse sand and transitional material, with this carpet (se estenderá à montante, e ainda o tapete vertical inclinado de forma a impedir ao máximo a )extend upstream, and still inclined vertical carpet to prevent the most of (saturação das faces á jusante). saturation of downstream will face.

It was the drainage system described  that failed in the B4.  Herculano, chose to continue processing  and use the unlicensed already full B1 without notice to or permission of the  regulatory authorities and also, apparently without any formal technical/engineering review of their ad hoc adaption of the B1. ( the construction of internal holding areas)

The EIS is dated 2013 but refers to a life of facility from July 27,2009 and anticipates a 6 year life/term of operation for the B4)  The cost is estimated at R$10.9 million (2009)


Lindsay Newland Bowker, CPCU, ARM Environmental Risk Manager

Bowker Associates Science & Research In The Public Interest

An Early English language report on the dam failure with Hercuano Mineraco’s public statement.

Essentially same account of indictment at

In Portuguese.the findings of fact.  Translation facility awkward but describes not just unauthozed use use but unauthorized major heightening of the B1 as confirmed in google earth photos. (lost this link will find and repost)

update in spring 2015 on damage assessment

action blocking reopening of socoimex steel mine impaired snce 2003

Posted in Causes Of Catastrophic Tailings Dam Failures, Herculano Indictment, Herculano Mine, Risk & Public Liability of Tailings Dams, Risk Economics and Public Liability of Tailings Dam Failures, Tailings Dam Failures, Tailings Dam Risk Management, tailings dewatering, Tailings Facility Failures 1910-2015, Tailings Failure Rates, Tailings Risk Management, Tailings Storage Facility Risk Management, Uncategorized | 1 Comment

Brazil’s Largest Newspaper’s Press For Truth & Full Accounting on Samarco Failure

Brazil’s largest newspaper, Folha De Sao Paolo, has been pressing hard  and with care and diligence to ask the right questions about the Samarco tailings dam failure on November 5th.  Their efforts serve not only the people of Brazil but the global community of leadership in responsible mining.   This post  provides the  full text of an interview between Lindsay Newland Bowker, Managing Director of Bowker  Associates Science & Research In The Public Interest, and Eleanora  Allgayer Canto  de Lucena . This interview was the basis of Ms. Lucena’s published article on December 12, 2015.  We are providing it here because there is no English translation of Ms. Lucenas  excellent article   and we felt it was important to bring forward both her excellent questions and our answers.

Chile, China, Peru and other nations are also allowing upstream tailings dam construction  which deviates  from well established and widely shared views  based on science and proof that this form of contsruction should not be used for any large dam.  In another Funha article also n December 12, there is a revelation that Samarco had been in the process of pre engineering to join the closed Germano Tailings Dam , also an upstream dam but buttressed and the then still exsting Fundao into one 225 million cubic meter mega dam. Folha reports that plan had never been mentioned to or or approved by Brazlian officials.  They report  that  Samarco had concluded that it could not create additional tailings storage capacity at the Fundao  through added height without also joining the two dams.

Any nation may under international law  enact any laws within the boundary of its recognized sovereignty. The repercussions of an event of this scale , however, are of global economic consequence  in financial markets.  The investors who relied on Fitch ratings glowing and seemingly informed July 2015 very positive review of bond offerings associated with  Samarco’s $3.2 billion expansion plan  were holding bonds rated as “junk” by Moody’s a few months later after the catastrophe.  In addition, the  thousands of investors, some of them unknowingly in the holdings of pension portfolios, or IRA’s have also suffered as yet unmeasured losses on their investments in BHP, Vale and Samarco.  A class action law suit in has been initiated and announced on behalf of U.S. investors. who  include  the school teachers, policemen, firemen, transit workers, and  blue collar workers to whom risk is ultimately passed through their pension fund managers.

When a nation such as Brazil, China, Peru , Chileg Canada allows deviations  from best science, best practice , best knowledge in order to facilitate and further  its own competitive advantage in world commodities markets and the continuance of royalties it earns on production it is essentially  transferring the public liability and financial risk risk beyond the  limits of its sovereignty.

In 1998, Samarco the first iron miner in history to meet the ISO 14 001 environmental standards and it has been monitored for compliance with World Bank and International Finance Bank (IFB) standards. Both Vale and BHP are  members  of the Mining Association of Canada ( MAC) who recently announced the recommendations of a year long task force  to strengthen its  member commiments to “zero failure” for TSF’s.  These recommendations and MAC’s policy does not contemplate rescinding Vale’s membership or BHP’s for its many violations of even existing guidelines of its members  operations in  foregin nations. ( Imperial metal owner of Mt Polley is also still  a member in good sanding of MAC)  So clearly there is no effective existing global mechanism that will prevent a transfer of risk consequence  from poorly framed national policy to citizens around the world.

Two nations, France and Norway  have transcended this gap in global checks and balances in financial markets through statutory programs of divestment.   While their national holdings are perhaps too small to deter miners, small and large , from practices that aim at quick  capital  and quick revenue through shortcuts on safety and envionmtal security, the quality of research and the established process benefit all markets all investors, all permitting authorities and other national policies on investment and management of publc funds.




Q What is your hypothesis about what caused the disaster in Brazil? Where did the the company fail? The President of Brazil has said the company was irresponsible. Do you agree?


Apriori we can say that all catastrophic dam failures are failed public private partnerships. The weakness in law and oversight that allows a the formation of a catastrophe sometimes over many years,is less frequently well examined or even acknowledged. But always in a failure of this magnitude government and miner are co –responsible. I read somewhere that funding had been crowd soured for a completely independent review.  It was a tiny amount and not sufficient to the task but that is what is needed to get to the whole truth of cause and I hope support will pour in from around the world to enable a truly expert , truly independent  multi disciplinary review.   The answers to your questions matter globally, not just in Brazil.

I know who I would hire. My expert panel would include experts on finance and economics as well as global experts on toxic torts and mining law. The Committees mandate would go well beyond the usual “proximate cause” of failure that is the customarily narrow scope of dam committee reviews.  Relying only on government contracted or miner issued data will never get to the whole truth.


It takes a very long time for a detailed and evidentiary analysis of “cause” to become “official”. Considering the scale of this disaster, the amount of “official” information on basic details is appalling and inexcusable. It falls to the permitting agencies and government to have this data in the first place and make it immediately public.


As a risk manager with more than a decades experience in risk management for high risk heavy construction  who has recently co -authored a major research paper on the risks , economics, and pubic liability of dam failures 1910-2010  I am  alarmed that there has been no official disclosure of any of the key and basic questions I have, that any risk manager  would  have about the failed dam:  its construction type, its total capacity, its height at failure vs its design height, the rate of raise of the dam height and the rate of deposition of waste materials as compared with design rates of deposition..


As with many large modern tailings facilities in Brazil, Peru, Chile and China the failed fairly new (c 2009) Fundao tailings dam may have been a super large un buttressed “upstream” construction. Upstream dams are the least stable and especially subject to loss and failure by non- seismic triggers related to rate of deposition of tailings,, height and the rate, of dam raise, active construction along the crest.  Certainly there is indisputable evidence that Samarco was using extremely high very steep upstream dams.  What isn’t clear is how that applies to the fairly new Fundao.


Bowker Associates is focused on that because of this “Culture of deviation” from known best practice which Samarco and some its consultants associated with the development and design of their mines within the Alegria complex describe as a “culture of innovation”. In official company statements and records it is clear that Samaco went ahead with its $3.2 billion expansion without adequate land surface area for the tailings and waste rock the dramatic expansion in production would generate. That’s almost universally the case.  It is also well documented that the reason Brazil, Peru, Chile are using the supersized  upstream dams is they are out of land surface area to manage the exponential increase in waste volume that attends each dramatic increase in production.


So, it is too early to have a pet theory but on the basis of an exhaustive review of all publicly available documents, I am looking most closely at the possibility that this was an upstream dam defying all established best knowledge and best practice in the name of “innvovation”


There is a fuller explanation and link to all doumentation we have found that may have a bearing in the catastrophe at my wordpress post.

Q  How do you compare this accident in Brazil with others around the world? In Your study of tailings dams and their accidents, do you find commonalities?


What is apparent here and what we have seen in our study of all tailings dam failures in recorded history at modern mines is that Samarco pushed ahead with a huge expansion in production without simultaneously developing and concurrently implementing an independently vetted plan for handling the wastes. In our research for Bowker Chambers 2015 we saw this pattern associated with smaller mines with lower quality ores by smaller less well capitalized miners.


Mt Polley is the prototype for that pattern.


The other commonality between the Samarco disaster and virtually all tailings dam failures in history is that it deviated from best knowledge, best practice and accepted standards and was completely predictable and avoidable.

Mt Polley, again is a very recent gravely consequential tailings dam failure where a pattern of deviation left unchecked for years finally ended in complete failure.

BHP, via a subsidiary , was responsible   for another man made modern tailings disaster at OK Tedi in PNG but the top 10 miners in general are better positioned to avoid the economic crunch junior and mid sized miners face. Their principal producing mines are larger and at higher grade deposits and the big miners have better revenue streams and better access to capital.

It is a major red flag to see this at a “top 10 miner” major production mine.

Very sadly, we may see more of this. I read recently that Codelco is investing $4.1billion to expand throuhput that will not even maintain their established level final metals output. This was also necessitated by declining ore grades and declining global prices.

These are the economics and realities that dramatically increase the potential for deviation from known best practice in tailings management and we predict will result in more and more severe catastrophic failures. of these super sized dams at these huge mines the “top 10 “control .

These failures will bring the consequence of failures to an entirely new level where as we see in the completely avoidable tragedy repair reclamation and remediation aren’t even feasible.

While these super dams have been in use (mostly not upstream construction) for more than a decade, Samarco was the first failure of a mega sized dam. Mt Polley’s dam was about half the size of the Fundao in total capacity and in dam height. The official record of ‘very serious” failures was almost entirely at smaller mines owned and operated by smaller and less well capitalized miners.

To me having just spent two years deeply and almost exclusively immersed in the ”official record” on tailings dam failures this is a very bleak landmark .

Even the big guys with much higher grade deposits are being defeated by falling ore grades and falling prices.

Q Are These Accidents Related to the End of Periods of High Prices?

Your study found a trend toward failures of increasing coseuqence in the modern times.Why Is That So?


Actually, the 100 year history of falling prices and falling grades for all metals over the past 100 years is about the costs to produce. On average over the 100 years until 2000, technology has lowered the average costs to produce sufficiently to more than off set falling prices.


The evolving modern trend to more serious failures had been mostly associated with smaller mines with  lower than average grrdes of ore  and  higher than average costs to produce ( the spot prices is the same for everyone on any given day )


What is happening now is that costs to produce are no longer offsetting lower grades even for the big guys as we see with Codelco. So it is really more a question of reaching the limits of what present technology has to offer to keep that spread between production costs and price working in ever and ever lower grades.


The equation of viability has broken down. It is beyond technology known and proven at this time to “fix”.


Q What is the best technology to handle iron mine tailings?

What companies use the best technologies and what are their costs?



Across all metals including iron, it is my advocacy that no new mine, no mine reopening, mine or mine expansion should be approved unless there is authoritatively vetted economic viability inclusive of all costs to properly manage wastes and conditioned upon the implementation of those best practices. That essentially was also Steven Vicks  commented in his capacity of Dam Review Committee member  for the Mt Polley failure in August 2014.


In other words, it is not a question of “best technology” it is more a question of whether there is any known proven technology for properly preventing harmful releases from all wastes of mining and from mining operations.


Q Should government take a stronger role in regulation and supervision of mining activities? Are there examples of better models of law and regulation that Brazil could look to in evaluating its own present policy?


Can Mining be a “sustainable” activity?


What that does this disaster reveals about the mining model used in Brazil? How ishould Bazil’s Law and Regulation be modified?


Mt Polley had already moved the mining industry away from its long term insistence on  law counting on  responsible self regulation to a call for sound law and regulation as an essential enforcer of responsble self regulation.  This just puts that in bold, all caps with lots of exclamation points.


The problem is no one has actually yet framed what that would like.


The closes we have seen and studied is West Australia who have regs based on a very well informed search of best knowledge and best practice but even theirs is not complete. It is an excellent place to start and especially relevant for Brazil who also have an iron based metal sector. But it too needs lots of work.  I cannot say that it would have prevented this disaster that has tragically befallen Brazil.

No single permtting jurisdiction could ever have the level of competence and experience to address and evaluate all the public liabilities inherent in any mineralized deposit. So Bowker Associates, joining  many other longer established voices for responsible mining, and responsible well informed public policy , is calling for the use of expert panels life of mine including properly vetted  expertise in mine economics and mine finance and  clear standards for what “expert” means.


These panels need to be available life of mine with long continuity in membership to address the emergence of public liabilities, before they arise after a mine Is permitted: a significant event, a planned stand by, a planned reopening, a planned expansion, any deviation from design height, slope, rate of deposition or rate of raise for an approved tailings facility and a regular schedule monitoring of  review of changes in cash flow and balance sheets, a regular schedule of  audits and on site inspections.


Bowker Associates work now is on trying to develop vetted meaningful “triggers” that would prompt engagement and review by the expert panel.

The expert panel recommendations should be binding on both the government agency and the miner. All expenses should be paid by the miner but with no direct control or supervision by either miner or permitting agency. (ie actually independent but with a clear  and comprehensive mandate)

Such a panel may have prevented the Samarco disaster but it may also have disallowed approval of the expansion without a concurrent vetted plan for management of the additional wastes it would create.

The entire axis of permitting needs to be vastly re oriented . Applications shouldn’t even be accepted without independent verified proof of economics, technological and environmental viability.




Posted in Uncategorized | Leave a comment



The Working Group met with State authorities, business, civil society and community representatives in Minas Gerais. The State has the highest concentration of industrial mines in Brazil, and the Working Group’s visit took place after the tragic disaster caused by the 5 November rupture of the Fundão tailing dam, in the district of Mariana. The disaster is referred to as the worst environmental disaster in Brazil.

(United Nations Working Group Site Visit December 2015)


The statistical analysis presented in this report uses the best currently available authoritatively cited data on the severity of the November 5 Samarco dam failure on the only two measures  of severity systematically recorded in global history for all significant incidents and failures of tailings dams since 1910: “Release”  the volume of tailings and water unintentionally released from the tailings facility(TSF); “Runout”, the linear distance from the TSF the release travels.   The severity in economic terms is not systematically captured on tailings dams failures in history  but recent collaborative) research ( Bowker Chambers 2015) has assembled authoritative documentation on about half of post 1990 catastrophic failures and so we use this research to compare the presently estimated economic damages of the  Samarco failure.

On these three best current measures of severity, the Samarco is without question the largest by far in recorded global history. 

The figures we use  for “release” , and “run out” are those also cited by the United Nationas Working group from their onsite reconnaissance and interviews with mine and government officials. .  The figures on “release” are  by known contents of the Fundao at failure.  This reported 55 million of tailings only at the Fundao makes no account of water volume there.  Post failure photos(see below) show there is no trace the Fundao ever existed.  Therefore the 55-60 million used by the UN and by Bowker Associates in this report most likely under estimates what will be finally documented as total release.


photo of two dams..

There was also a confirmed release overtopping the Santorem but the details of that and the amounts of water involved have not been specifically disclosed by the Brazilian government or the miners.  Photos of the Santorem post failure  show extensive damage and loss of contents and structure.

The Samarco Failure In  Recorded World History

The November 5th failure of Samarcos’ newly constructed Fundao Tailings Dam1 (c.2010) significantly exceeds the severity of all reported failures 1915-2015 on three measures of severity: volume of release, ( 50-60 2 million cubic meters), run out (500-600 km3), and environmental and other damages.($5.2 billion 4). These three descriptors are independent measures of the scale of offsite damage and the ultimate likely risk of un funded un fundable public liability.

While the exact numbers remain a little “fuzzy”, as is always the case, sometimes for years, following a tailings dam catastrophe, the difference in magnitude relative to past catastrophes makes it unmistakably clear that the Samarco failure is the worst in recorded in history on these three measures of severity.

The “official record” ( Wise/ICOLD as recompiled by Bowker Chambers 2015 (5) has data on release for only 128 (47%) of 269 recorded adverse events (inclusive of Samarco). 157 (58%) had data on run out. There is also no systematic capture of data on offsite damages including liability damages to impacted residents and businesses. More than 1 year past Mt Polley, there is still no official accounting of loss and damage. Competent, informed estimates are available for only 8 of 18 ,62% catastrophic events post 1995 )

The cumulative release and runout by decade historically ending on the date of this man made and avoidable catastrophic failure, makes it very clear that despite the difference in magnitude the Samarco man made catastrophe  is on a very clear trend line to TSF failures of greater consequence.


The release was initially esitmated and acknowledged by BHP at 60 million cubic meters. and estimate that was based on the tota talings in te Fudao and the Santorem which was also  initially believed to have failed completely8). BHP has more recently that the Fundao contained an estimated 50 million of tailings and that there was no breach at the other two dams in the compex, the Santorem and the Germano.  An entirely new number has appeared at WISE, and in a recent university report on damages,  35 million cubic meters but without source or explanation. Brazilian offcials are still citing 60 million. In any of these cases 35 million to 60 million, it is still  the largest release in recorded history . The next largest , Tubu,  #2 ,Benguet Philippines (1/2/92) ,  was  32.2 million cubic meters. Only 5 tailings dams in recorded history have exceeded 10 million cubic meters of release.

In the following charts we have chosen the figure 60 million cubic meters as an estimate of total release not because it is the highest estimate but because it is most consistent with the miner reported 50 million cubic meters of tailings in the dam as of release, not accounting for water , with photos which show a complete loss of all material from the Fundao ( water and tailings) and most consistent with the scant data on throughput  and likely generation of wet aligns from that throughput.  Bowker Associates thinks it likely the actual final documented data on “release”, total volume of contents, water & tailings, lost from both dams, may well exceed 60 million cubic meters especially when the overtopping from the overwhelmed Santorem is factored in.

Release volume in Historical Context


Bowker Chambers (2015) (6) set 1 million cubic meters or more as the threshold for a “very serious failure”.  In recorded history through 11/05/15, the date of the Samarco failure, 1915-2015 there have been only 70 “very serious” failures. (This includes one newly documented catastrophe in Mexico in 1937 that has only recently been authortaively described)   The larger and higher the facility the greater the release volume. The chart above  puts the magnitude of this failure, as measured by release volume in historical perspective.using Bowker Associates best estimate of  60 million cubic meters  based on photos, scattered documentation on tailings contents, water & tailings, and an estimate from an SEC filing of  total wet tailings generated by Samarco from 2010 through 2014.( over 90 million cubic meters).


Where Are We In History On Release Volume Trends?


The chart below shows the trend in aggregate release volume by decade from 11/6/55-11/5/2015 for the 129 failures, unintended releases and significant events with data recorded on release volume. The exponential increase in total volume of release from all events has escalated from only 6 million cubic meters for the decade ending 11/5/65 to 107 milion cubic meters for the decade ending on the date of the Samarco failure, 11/5/2015.

wordpress agg release


On the basis of this high R Squared exponential fit we can predict the aggregate for the decade ending 11/5/2025 to be 123 million cubic meters. In addition to the absence of any documentation for 123 of 269 events (46%),. two “very serious” failures  in the decade ending 11/5/2005 had no data on release at all. They were classified based on other authoritative documentation on severity.  Assuming the distribution of release values is the same within each decade, then a correction for under reporting on a straight percentage basis would put the estimated aggregate release volume globally for the decade ending 11/5 2025 at  267  million cubic meters.   A conservative estimate is that It will be more than double what it has been for the decade ending 11/5/15.



Run out is the distance from the point of failure the released contents (tailings and stored /accumulated water) travels. For a given volume of retained tailings& water content , higher dams will have a greater run out and therefore affect a larger area. In dams of the same height those with more water or liquid contents will have a longer run out.  The likely run out of a dam in design stage can be reasonably well calculated by this simple formula long before a commitment is made to build it taking account of specific local conditions.

Run out of the Samarco failure has now reached 500-600KM , the upper range twice that of the 2nd largest of 300km at El Porco Bolivia on. August 29, 1996.

There are only 7 events in recorded history with a run out greater than 100KM.


wordpress runout 1

“Official history” has recorded data on runout for only 157, of the 269 authoritatively documented unplanned releases , failures and significant incidents.

The force of the outflow from the Samarco was extremely powerful. The  town of Bento Rodriquez  2.5 km from the Fundao  was completely destroyed. 8km further downstream a police officer reportedwall of mud 2.5 meters high still flowing.  Five year old Emanuely Fernandez was swept out of her fathers arms as he tried to outrun the flow. Her body was found  40 km downstream. ( ) The body of a mine worker was found 100km from the mine site..

The outflow was reported estimated at 400 km in the week following the catastrophic failure but has now reached the Atlantic ocean just north of Rio de Janeiro 663 km downstream and still carrying soils and sediments from the flow. The Rio Duco is completely destroyed and some experts have estimaoted it will take  100 years to recover.  At its mouth a carpet of dead fish lay on beaches and on the waters surface.


Where We are in History on Trends in Run Out


The following chart aggregates runout by decade for each decade ending on the date of the Samarco catastrophe, 11/05/15. A clearly and dramatically escalating trend is apparent in the data as reported from 126.7 total kilometers for the decade 11/6/55-11/5/65 to 722.2 total kilometers for the decade ending the day of the Samarco failure. A strong R Square to this linear fit supports an estimate of 723.5   for the decade 11/6/2015-11/05/2025. Important to stress again that this is not a full accounting even of the run out for the most serious failures in all history.  The actual cumulative run out for all failures, unintended releases and significant incidents this coming decade will significantly exceed what is predicted by this chart based on reporting for only 58% of all incidents. Assuming the same distribution of values within each decade , and accounting for under reporting on that basis  puts the actual estimate of cumulative runout for the coming decade) at 1,247 km. without a course correction in the legal framework for permitting and oversight of mines and a concurrent improvement in self-regulation within the industry

wordpress runout aggregate by decade1



Governement prosecutors are suing for damages of $US 5.2 billion based on technical reports and assessment. Researching court records and other government data  on “Very Serious Failures”, Bowker Chambers 2015 (6)found only one in recorded history post 1990 with damages as high as $1billion; Taoshi, Linfen City, Xiangfen, Shanxi Province, China, at $1.4 billion ( $2014).

“Valuation” at the scale of these super catstrophe’s is not the same as “cost of clean up” or “remediation” which may not be economically viable or technically achievable.


It will take a very long time to get authoritative and final confirmation of release volume, runout and estimated offsite damages, however it appears on the basis of what is availlable now that the November 5th dam failure at Samarcos mine in Brazil is without question the largest tailings dam failure in recorded history.


Lindsay Newland Bowker, Managing Director

15 Cove Meadow Rd.

Stonington, Maine 04681

207 367 5145


December 12, 2015

FOOTNOTES & REFERENCES ( This needs a major edit but is still useful in this form)


1/Petley, David, “History of the Fundau Dam”, November 10, 2015   last accessed December 3rd at   This post includes a series of google earth images of the Fundao dam site from virgin earth in 2003 to 2013. The dam first appears as complete and obviously in service in the 2011 photo. The 2013 photo shows a dramatic increase in height from 2011. Photos show an “upstream dam” of extraordinary height.

2/  Release is total contents unintentionally  lost from the impoundment and includes total contents, tailings and water.  It is clear from the hotos that there is no trace left of the Fundao.  All of its contents tailings and water were released. The most recent estimate of tailings at the Fundao alone is 55 million cubic meters, not accounting for water lost.   Flow into and over the Santorem which reportedly contained 12 million cubic meters in tailings and a large amount of water has been acknowledged  but not documented by officials.   Our working estimate of 60 million cubic meters seems a solid  best estimate based on all data and photos available to date .

3/Both 500km and 600km have been variously cited..Government is still citing 600 km.WISE is reporting 663Km . For the purposes of our chart work and stats we have elected to use 600km.  As a matter of practice we use round whole numbers unless exact measurements are being reported.

4/”Brazil Sues BHP, Vale &Samarco for $7.2 billion Over Mine Disaster” Reuters as reported last Updated Tuesday , December 2, 2015 atABC.Net.AU    Last accessed December 3, 2015     In Brazilian  Real the amount cited by Brazilian officials is $US5.2 billion.  This  is an Australian newsource and the figure $7.2 billion may be in  Austraiian dollars . Note, this source also uses 60 million cubic meter release.

5/The “official record” as maintained and publicly accessible ( though not in machine readable download form) is maintaned by the World Information Service on Energy   (WISE): Chronology of Major Tailings Dam Failures (from 1960) accesible at .It’s original core was a survey by ICOLD ( International Committee on Large Dams) complied from anecdotes, recollection and questionnaire through 2000. In the course of research for Bowker Chambers 2015 (6) we noted several omissions in the WISE compilation that were authoritatively documented outside of WISE/ICOLD and also several inconsistencies between the WISE compilation and the original ICOLD compilation as reported in Bulletin 121. The authroitaitvely reconciled and complete accounting, “TSF Failures 1915-2014” is available in excel downloadable form and is what is referred to here  aa  “the official record”.   Bowker Chambers 20156 attempted ,and in a few cases succeeded in ,adding  authoritatively  sourced detalis on run out, dam height, storage caacity, release, deaths, that were not part of the  WISE compilation..  The Bowker Chambers “Official record” is thoroughly sourced and referenced..

6/Bowker, Lindsay Newland Chambers ,David M. “ Risk Economics and Public Liability of Tailings Facility Failures”, Appemdix III published at   Earthworks July 2015  Also available at Technical Reorts www.csp2.orgo


Posted in alegria mine, Analysis TSF Failures, BHP, Bowker Associates Science & Research In The Public Interest, Brazil 's High Grade Iron Ores, Causes Of Catastrophic Tailings Dam Failures, Center For Science In Public Participation, CSP2, dam failue envronmental costs, David M. Chambers, Economics of Iro Ore Mining, Environmental Risk Management, Frequency of TSF Failures BY Decade, Fundao Talings Dam, Germano Tailings Dam Failure, Global Capital Squeeze In Mining, global cash flow crunch, Height Limits of Earthen Dams, ICOLD BULLETIN 121, Lindsay Newland Bowker, Measuring Magnitude of Consequence TSF Failures, Metallic Mining Risk Management, Mine Risk Management, Mining Economics, mining environmental risk management, Mining Financial Feasibility, mining public liability, politics of mining, polluter pays, Public Liability & Financial Risk, Rate of Raise for Upstream Tailings Dams, Risk & Public Liability of Tailings Dams, Risk Avoidance & Loss Prevention Metallic Mining, Risk Economics and Public Liability of Tailings Dam Failures, Samarco Mineracao S.A., Samitri, Tailings Dam Failures, Tailings Dam Risk Management, tailings dewatering, Tailings Facility Failures 1910-2015, Tailings Failure Rates, Tailings Storage Facility Risk Management, TSF Design & Management Standrds, Uncategorized, unfunded public and enviornmental liabilities, Upstream Tailings Dam Safety | Leave a comment

Samitri Samarco & Vales Use Of The Failed Fundao Tailings Dam

Brazilian Paper Estadao reported on December 8th that Vale’s use  of the failed Fundao has been at least 28% of total and that there is no legal basis for this use.  This article  follows up on long standing and widespread reports that Vale, a 50% owner of Samarco, had been using the failed Fundao for its own tailings.   After first denying any deposition there, Vale later acknowledged that they had contributed “at most 5% of total ” under a contractual agreement wih Samarco. The December 8th Estadao account  reveals that the contractual agreement cited is actually with Samitri, original owner of  the rights at Germano.  The cited date of that agreement predates the design and construction of the Fundao by many years. (Best data suggest the Fundao first received any tailings c. 2009)

It is not clear whether Vale’s July 2014 transfer of mining rights in two mines at its Alegria Complex to Samarco ( and BHP’s transfer of other interests to JV partner figure into the initial  and persistent report that Vale had been transferring “large volumes of tailings” to the Fundao.  Th e language used by Vale  in responding to these charges  of shared use of the Fundao   is less than clear and neither Samarco nor Vale has offered historical records in support of public statements.

Vale has acknowledged that its use of the Fundao accounts for  about 5% of all tailings there as of the date of failure. BHP.,Vale & Samarco all consistently state ( again with no supporting actual records) that the total content of the Fundao was 52 million cubic meters at failure. ( More recent data reported at Folha on December 12 puts that at 55 million ) That would put Vale’s total contribution over the 6 year life of the Fundao at 2.6 -2.8 cubic million cubic meters.

The5, not disputed by Vale, is  an interesting an important revelation for many reasons from a risk management, liability point of view, the point of view from which we have been researching and analyzing this largest ever tailings failure in recorded history.

(1)   The legal design approval and use of a tailings dam is pursuant to a permit which would customarily stipulate/assume complete management control by the permit holder.  Rate of deposition, rate of dam raise, means and methods of deposition, and profile  of  deposited tailings are all critical to dam stability, especially in an upstream dam, the type of construction at the Fundao.

(2) Unless specifically referenced in the permit or any subsequent amendments, no external or prior agreement can modify or over ride any provisions of the permit.   Did the permit allow Vale’s use and under what terms and conditions?  Did the design plan for an accommodate both Samarco’s and Vale’s planned use?

(3)  How was the actual deposition of Vale’s tailings managed to account for volume, characteristics of materials deposition, and placement in accordance with design guidelines.?

(4)  Did the permit for the Fundao make any stipulations viz compliance with all guidance on Fundao’s design?

(5) A contract can’t  supersede or contradict law.  subsequent changes in law or regulation would nullify any contracts or agreements unless the law foolishly. as most do, applies only to permits issued after the effective date of the new law (ie grandfathers all  already permitted mines)

(6) This makes Vale presumptively co responsible for the failure at the Fundao. notwithstanding any language between Vale and Samarco stipulating that Samarco is solely responsible.

Samitri Samarco Vale  BHP

Samarco was effectively created out of a 1973 joint venture agreement with Samitri ,original leaseholder which traded a $ 600 million   investment by Samitri for Samarco’s promise that proceeds would build a transporation export system that would make Samitri product deliverable to USA markets. Samitri sued Samarco for fraud alleging that Samacro never intended to create access to U.S. Markets and, in fact, hadn’t accomplished that. Samitri sued Samarco for fraud alleging that Samacro never intended to create access to U.S. Markets and, in fact, hadn’t accomplished that.

Under the agreement Samitri was guarantor of all Samarco’s debts and liabilities, allowing Samarco to seek capital in its own name for the project the two planned.

Pursuant to the original Shareholders’ Agreement, the parties executed a number of so-called stock purchase agreements under which Samitri and the Defendants together purchased a total of approximately $400,000,000 of securities in Samarco (the “Stock Purchase Agreements”). On August 16, 1979, the parties executed an agreement whereby Samitri and the Defendants agreed to guaranty Samarco’s debts and liabilities (the “1979 Guaranty Agreement”). And on July 23, 1982, the parties consented to an additional agreement under which Samitri and the Defendants were required to purchase even more securities in Samarco (the “1982 Memorandum of Agreement”). These agreements entered into after 1974 are collectively referred to by the parties as the “Post-1974 Agreements.”

“On December 23, 1982, after learning of the cancellation of certain of Samarco’s major contracts to supply iron ore products to United States purchasers, Samitri sought to withdraw its interest in Samarco and to rescind each of the contracts between itself and the Defendants. Subsequently, on March 22, 1983, Samitri brought this action to obtain, inter alia, a declaratory judgment that it had lawfully rescinded the 1974 and Post-1974 Agreements and a restoration of the status quo ante, including restitution of approximately $200,000,000 which it had paid for securities in Samarco.”

op cit above

BHP Acquires 50% Interest In May 2000

In May of 2000, BHP acquired a 50% interest in Samarco via acquisition of 63% interest  in Samitri  by CVRD(Vale) from the Arbed Group for $525 million.  At the time of this transaction  (CVRD of 63% of Samitri) BHP already owned  49% of Samarco  dating to 1984 and Samitri owned  51% ( CVRD acquired controlling interest in Samitri).  Following the CVRD acquisition, BHP, by previous agreement acquired  an additional 1% in Samarco creating the present 50:50 joint venture between Vale ( CVRD) and BHP.

The objective was “to rationalize the Alegria Iron Ore Complex” via the 50:50 joint ownership of Samarco who had already begun that process through its arrangements with and  financing from  Samitri.

 “The agreement between BHP and CVRD will facilitate the  restructuring of Samitri and Samarco operations aimed at increased efficiencies, reducing costs and improving Samarco’s product quality.

President BHP Minerals Ron McNeilly welcomed the agreement with CVRD, the world’s largest iron ore producer.   ‘It is a practical demonstration of BHP’s portfolio management activities designed to capture synergies in key business areas by partnering with major industry players,’ Mr McNeilly said.

‘Purchase of the additional 1% shareholding in Samarco provides BHP with joint control of a high quality asset which enjoys strong demand for its products. We expect to capture significant operating  efficiencies and savings between the neighbouring Samarco and Samitri mines.”

Speaking again in a”claims management litigation support ” voice of a Risk Manager and returning to the Estadao story which points back to arrangements with Samitri,  this would seem to suggest that it was BHP’s aim and purpose as well to give two distinct separately permitted mines in the Alegria complex lower costs and better efficiencies through shared infrastructure.  Specifically this suggests the possibility that Vales use  the Fundao is fully consistent with the intent of the 2000 agreement creating the 50:50 ownership of Samarco.

From a risk management/liability management point of view the question is to what extent the permit conditions provided explicitly for this shared use of infrastructure within the  Alegria complex, and whether local permitting officials were aware of these “synergies” and provided appropriately for it in the permitting of each separate mine within the complex.

As a risk manager with considerable expertise in high risk heavy construction, I would say these synergies might make business sense, but they greatly complicate permitting and regulator oversight, as well as complicating proper liability management.  It needs much further examination of  a great deal more information to assess.  Most regulatory and legal frame works would not be set up to take the implications of these “synergies” into account. especially involving high liability elements like tailings dam and waste rock piles.

The Estadao article suggests that what BHP Vale saw as “synergy” was not legal as respects any shared use of the Samarco tailings facility and its permit and that the Government had no “official” knowledge or approval of this particular “synergy”.  “Official “here means explicit in the permits and any amendments to them.’

I will be adding more details and structure to this post as new information becomes available.

Lindsay Newland Bowker, CPCU, ARM, Environmental Risk Manager

Managing Director

Bowker Assciates, Science & Research In The Public Interest

15 Cove Meadow Rd Stonington Maine 04681

207 367 5145

December 8, 2015 Cove Meadow







Posted in BHP, Fundao Talings Dam, Samarco Mineracao S.A., Samitri, Uncategorized, Vale SA. | Leave a comment

Brazil Initiates Environmental Crimes Investigation Against Vale, BHP and Samarco Officials On November 5th Tailings Dam Catastrophe

Fact is BHP know why it failed. They just cannot tell us until the lawyers have vetted the communications why they ignored their peer reviewers, their consultants, and their FNEAs until people were dead

They had an FMEA PIG plot that showed that failure was of low probability albeit of high consequence. PIGS don’t fly, and did not in this case and they said OK live with the risk.

And the risk came to reality.

Jack Caldwell

This latest action in the still unfolding story of  what lead up to the largest tailings dam catastrophe in recorded history, reported by Paul Kiernan in the Wall Street Journal is apparently what Jack Caldwell is pointing to in his almost hidden post above.

In Mr.Caldwells post, the  “peer reviewers” included the renowned Dr  A. MacGregor Robertson, a career long champion of  responsible self regulation promoted through his entity Info Mine . Dr. Robertson was long term adviser to the project but has not been close to the project since 2011.  (Apparently Samarco had an Internal Tailings Reiew Board f independent experts) “Consultants” refers to Dr. Joaquim Pimenta De Avila,  engineer retained in 2007 near completion of the Fundao and a member of the “faculty” at Info Mine. Dr. De Avila who was replaced in 2012 apparently by a Geoesteval, a heavy construction firm with  experience in water dams but no experience at all in  Tailings Dams or mining, remained associated with the project  under a limited scope of services until 2014.

In circumstances apparently similar to those leading up to the  Mt. Polley failure Dr. De Avila had been advocating  more costly risk averse, loss control measures for the tailings facility than fit with Samarco’s emphasis on economics and cost control. We have not seen the text of Dr. De Avila’s  public statements and deposition to police but Mr. Caldwell’s statement implies that a buttress for the Fundao was among those recommendations.  This was not part of the original Fundao design, which did not include or provide for an expansion of the scale and volume announced by  Samarco in 2010.  It seems likely that Dr. De Avila had urged design modifications that had been specifically rejected by  Samarco. Vale was fully aware of this inadequate tailings capacity through its own independent technical evaluation of the $3.1 billion expansion .  Both Vale and Samarco  elected  to  go forward with implementation of the expansion and its dramatically greater  throughput fully aware  not only that the Fundao could not accommodate this increased waste volume and fully aware  that there was not sufficient space on site to create this capacity.

Dr. De Avila made  further recommendations in the scope of his official continuing capacity in 2014 based on observations indicating stress in the dam.  The details of those recommendations and of Samarco’s denial  of any knowledge of these reported observations of stress conditions    are apparently central to the “Environmental Crimes” investigation now underway.

Knight Piesold, original designer of the failed Mt. Polley TSF also being pushed beyond design limits for an unplanned expansion  on throughput was let go as it pressed Imperial to address the issue of the dam’s structural stability and  its capacity to safely absorb  the escalated volume and rate of deposition of tailings.

According to his public statements, Dr. De Avila ‘s contractual relationship with the project  ended in 2014. Presumably under advice  and  direction  of Geoesteval,  in charge of the Tailings Master Plan and the all to do with tailings ( as described in some detail at their web site) a different design modification was made to the Fundao in 2014  than what  De Avila had recommended.

It is now known that Geoesteval’s  master plan to create capacity was to remove the wall between the officially closed  Germano  joining it with  the Fundao to create a single mega TSF. At the time of collapse unauthorized work was underway to prepare for removal of the retaining wall between the old Germano and the stressed Fundao.

Other public documents and government public statements have repeatedly mentioned that work to raise the Fundao was also underway at the time of collapse.   That raise was presumably within  the completed altered  configuration changing the original design and not including his recommendations to Samarco for how to modify his orignal dam.  It is not clear what peer review or independent technical evaluation was undertaken of the design modifications Samarco elected over Dr. De Avila’s.  Jack Caldwell’s comments suggest that peer reviewers and independent consultants agreed with Dr.De Avila and that Samarco simply elected to take a different path.

Further information on the specifics of Dr. De Avila’s testimony to police on the Envionmntal Crimes investigation indicates that he was asked by Samarco to create “as built drawings”  for submission of required documents for envionmntal permitting and refused ( the dam was not completed at the time he was asked to make the “as built” drawings.

It is  not clear whether Dr. De Avila has been retained as expert adviser to the police investigation of Environmental Crimes against Samarco and Vale or subpoenaed or just has voluntarily come forward in the public interest.


Samarco and its joint venture owners, BHP and Vale have repeatedly  pointed to the July 2015,inspection report characterizing it consistently as evidence that the dam was structurally sound.  Vog BR conducted that inspection and issued that report.

On January 14,2016 after being named in the police investigation of Environmental Crimes, VogBR President Andre Euzebio  issued a “Notice of Clarification” at their website speaking to their role in that report and its meaning in the context of law .

That statement clarifies that their report was based solely on documents and records provided to them by Samarco, seeming to imply that no actual independent inspection of the dam was undertaken (ie a desk report).

The Regular Safety Report was prepared considering the historical background  readings of the geotechnical monitoring instruments  and other documents. The collection and provision of the documents is the dam owner’s responsibility. VOGBR used this data to calculate a dam safety factor  and conduct a stability analysis  as required by  applicable regulations (Law 12,334/2010,DNPM Ordinance 416/2012, and Standard NBR 13/028/2006)

This report was prepared with all technical rigor and with all  relevant and necessary technical information about the condition of the dam in July 2015.  It is important to note that the conditions depicted  in July 2015 were not the same as the conditions at the time of failure on November 5, 2015  due to ‘dam operation dynamics’.


As further stated in the “Notice of Clarification” VOGBR had been retained by Samarco to design a planned raise of the Fundao 20 meters beyond the original design which the report attributes to Dr. De Avila.  They don’t indicate whether that work had involved actual site inspections or independent measurements.

The January 14th statement  provided further information on the Drainage issues they had been retained to address in accordance with the recommendation of Samarco’s  “International Tailings Review Board” (ITRB) ( which may have been the vehicle through Which Dr. Robertson advised on the project and also be the peer reviewers Jack Caldwell refers to. Dr. Robertson is a core member of  another Independent review Panel for Seabridge at KSM).  The  ITRB  had recommended shoulder drains, according to the statement.  The original Pimenta De Avila design, they say, provided only for drains in the center of the TSF and did not foresee the need for or provide shoulder drains.. The following from the site translation of the original Portuguese text.)

The dam project, prepared by the company Pimenta de Avila, predicted internal drainage in the elevation 826m, only the central portion of the structure. Esse projeto não contemplou drenagem interna na região das ombreiras. This project did not include internal drainage in the area of the shoulder pads.

Samarco, through its international consultants – ITRB (Internal Tailings Review Board) – recommended the establishment of drainage on the posts, which were not foreseen in the original design of Avila pepper

The statement concludes wit the assertion that VGBR offered no opinions on and was not involved  otherwise in the Fundao’s design or its operation.

Conflict in Information On Dates And Nature of Dr. De Avila’s Role In Design Of The Fundao 

Dr. De Avila, who has not been named in the Environmental Crimes investigation has reported his dates of service with Samarco as 2008-2012 with a different and lesser consulting role to Samarco 2012-2014.

Authoritative statements elsewhere say the Fundao was placed in service in 2009 which is consistent with the google earth photos at Dr Dave Peley’s web site showig the dam in construction prior to 2008.

Dr. Avila has not, to our knowledge,  provided a public description of his work for Samarco and Vale. VGBR’s statement asserts that Pimenta De Avilar  authored the operation manual for the Fundao.

Other Legal Actions

Other active legal actions include a $us5.2 billion lawsuit by the Brazilian government against Samarco, BHP and Vale and a class action lawsuit on behalf of U.S. investors.

Herculano , also in MInas Gerais have been indicted on 1st degree murder charges for worker death in their 2014 tailings dam failure.  Most of the 17  confirmed deaths in the Samarco catastrophic failure were also of workers .  Some works have still never been found and are presumed dead.  A senior official of the workers union who worked at the Samarco mines has publicly stated that  concerns about worker safety had been expressed to Samarco  for awhile before accident.  No murder charges have been mentioned publicly so far in the  Samarco failure.

In the coming days, we expect further details on the Environmental Crimes investigation , in particular on the nature of  De Avila’s observations on structural stresses observed and reported to Samarco  in 2014 .

Contact Information:

Lindsay Newland Bowker, CPCU ARM, Environmental Risk Manager

Managing Director, Bowker Associates Science & Research In The Public Interest

Stonington, Maine   207 367 5145


additional press on environmental crimes investigation

 Other Recent Prosecutons for Environemental Crimes

“Anchorage, Alaska – U.S. Attorney Karen L. Loeffler announced today that James Slade, 57, of Calgary, Canada, was convicted after a two week jury trial of two counts of violating the Federal Clean Water Act by polluting the Salmon River with turbid wastewater from the Platinum Creek Mine he was in charge of operating.  A sentencing hearing is scheduled for November 12, 2015, and Mr. Slade was ordered to surrender his Canadian passport and remain in the United States pending his sentencing.”

“WOES keep on piling up for cash-strapped Talvivaara, with the police revealing in mid-October that several of the mining company’s employees are suspected of aggravated impairment of the environment. Over the past two years, the economic crimes unit of the Oulu Police Department has scrutinised activities at the Sotkamo-based mine, since its planning and construction phases until the most recent waste water leak in April this year.

Officials have characterised the pre-trial investigation as exceptional and challenging due to the mine’s complex production process”

“While Barrick employees continued to appear before San Juan Judge Pablo Oritja yesterday to give testimony over the incident, the company and the officials who authorized its activities came under more judicial scrutiny yesterday as federal prosecutor Ramiro González agreed to open a criminal investigation following a complaint by environmental lawyers.

This second investigation, separate to the probe launched by federal prosecutor Federico Delgado a day earlier, named Environment Secretary Sergio Lorusso, Mining Secretary Jorge Mayoral, San Juan Environment Secretary Domingo Tello, the president of the San Juan Mining Chamber Santiago Bergé and the leadership of Barrick Gold Argentina as persons of interest.

“Just this week, MiningWatch Canada and the International Civil Liberties Monitoring Group released a damning report linking Canadian mining interests throughout the Americas with intensifying repression and violence against mining-affected communities.

The new report—entitled In the National Interest? Criminalization of Land and Environment Defenders in the Americas—argues that “the model of industrial mineral extraction that Canada promotes abroad is informed by deregulation of the extractive sector at home and a colonialist past and present that—with renewed fervor in recent years—views those who speak out as a threat to the national interest and hence a target for spy agencies, tax audits, funding cuts, and gratuitous policing.”

“Far from ensuring that mining-affected communities enjoy the full range of protection under the law, governments—including the Canadian government—have twisted the law to protect and promote mining interests by targeting community activists and defenders,” said Jen Moore, Latin America program coordinator for MiningWatch Canada. “It has become a low-intensity war against communities and organizations who are fighting for environmental justice in Latin America.”








The Samarco Story

The first images which became available over night  in the hours immediately after the November 5 2015 collapse of two of three tailings dams at its  Alegria Mine complex  in the  State of Minas Gerais  Brazil.are horrific and apocalyptic.  Five-year-old  Emanuely Fernandes was swept out of her fathers arms as he tried to outrun the slide, her body found 40 km downstream.

residents reacting to landslide caused by failure or germano mine tailings dams

Before it was swept away, it was an old well established and  very beautiful area .

old benito rodrigue before the flood

Now it is literally gone.


“In front of a house that was both imposing and impeccably clean, without a trace of muck, there were four workers, equally clean, engaged in tending the plants.  Not one of them was willing to identify himself or talk to the reporter – “Samarco itself  is the only one to be talking” according to one  – but in the end the workers let slip that the house was a country residence owned by a Diretor of Vale, the company that owns 50% of the shares of Samarco,  as part of a joint venture with another mining giant, BHP Billiton.”

Joana Tavares, Minas Gerais

By the 22nd of November the flow reached the Atlantic just north of Rio De Janeiro 600km downstream of the failed Fundao dam coating beaches and the oceans surface with dead fish.

Two other very large dams in the complex , the original old Germano and the newer smaller Santorem, were impacted and are being shored up. with rock buttresses  to prevent their failure. Initially BHP had reported failures of both the Fundao and a smaller older dam downstream, the Santorem.


A Wall Street Journal article November 24 confirms earlier reports that Vale had also been using the Fundao tailings dam but Vale spokespeople claim it was less than 5%.on an annual basis  Estadao reports on December 8, however that Vale was responsible for 28% of the total tailings depositions at the Fundao and that its use is illegal. Vale is citing a very old agreement with Samitri, original leaseholder at what is now the Alegria complex, which pre dated the construction and permitting of the Fundao.

This 2010 Vale technical report independently  reconfirming Samarco’s reported reserves  in supporti of Samarco’s $us 3.1 billion expansion project indicates the engineers  concern about adequate space within the  Alegria complex for the waste that  would be created in the planned expansion and step up in annual production  .

Of greater interest relative to potential impacts to the stated reserves is the surface use status of the future waste disposal area which is a private property preservation area established under Federal law to conserve ecological processes, biodiversity and for protection of flora and fauna

At the time of this report the Fundao dam was already constructed. and beginning to receive tailings.

The firm Geoesteval was in charge of the master plan to solve Samarcos space problems for waste management according to their website.

This is joint owner BHP Billiton’s  second association with a catastrophic tailings dam failure in modern history.(OK Tedi Papua New Guinea) The Tailings dam at their Olympic Dam Mine , acquired by BHP in 2005,  has presented serious ground water contamination from improper linings.

bhp ok tedi taiingsdam failure

Source Papua New Guinea Mine Watch BHP’s OK TEDI Dam Failure

“When we start mucking around with the basic rules and the basic principles of the mining industry, that is when we allow the possibility for shortcuts and wrong interpretations to flow into the equation, and that often leads to a disaster.”  Neville Rockhouse

Neville Rockhouse was the safety manager at  the Pike River  mine in New Zealand and the father of  one of the 29 killed in that disaster 5 years go November 19.

In the years since the disaster, Mr Rockhouse has emerged as a campaigner for safety and corporate responsibility.  His quote, above to Sydney Herald journalist Peter Ker points in the right direction for ongoing inquiry on this disaster.

Key Questions Are Whether Height, Rate Of Raise, Slope and Deposition Procedures In Accordance with Consensus Best Knowledge  Best Practice

As a risk manager of long experience with high risk heavy construction and as co author of a recently released major research paper on the risk economics and public liability of tailings dam failures, my own unanswered questions and ongoing focus of inquiry are on the design and construction of the original dams and their modifications to accommodate dramatic production expansions at Samarco’s Alegria Complex. In particular the scant technical information I have been able to assemble and report below  points to the possibility of rsgnificant departure from long established and widely shared “best knowledge” and “best practice” on the height, rate of raise and slope of upstream tailings dams.

Brazilian prosecutors are also focusing on these issues. in particular whether the rate of raise at the Fundao  and its height contributed to failure.

No Official Public Records Or Technical Reports  On The Fundao Or Other Dams In The Complex

We have found no text confirming the history of the three dams referred to and no technical documentation on their original design and construction.

Estimates based on scant  authoritative data indicate the Fundao pushed and perhaps exceeded the limits  of Best Practice/ “Best Knowledge” on  height and slope , rate of raise and rate of deposition ..

This from 4 data sources: the  president of the mine workers statement that the dam was “the size of 10 football fields”, BHP/Vale claims that the Fundao held 50 million cubic meters  “of tailings”at failure and google earth photos which show that the Fundao was put in service c 2010, is an un buttressed upstream dam with a very steep face and that there was a very large change in dam height between 2013 and 2015.

As further reasoned out below, this puts the estimated height of the dam at failure at 78 meters, and indicates a rate of raise  of  15.6 meters per annum and a rate of deposition of tailings  of 2 million cubic meters per year. from the time it was placed in service c2009 (is  now confirmed by the design engineer that the height of the Fundao at failure was 90meters and the the rate of raise had been 15 meters per year)total tailings deposition has been confirmed at 55 million cubic meters).   Although the height and  use of  upstream construction  are consistent with local practice in Peru, Chile and Brazil due to the  mountainous terrain and the limited availability  of land space, this South American practice violates globally accepted  standards for upstream dams.  Without these variations from Best practice/ Best Knowledge many South American mines could not be mined at all or continue large scale expansions.

The key guidance on ths is in ICOLD (International Committee on Large Dams),WISE(), and Martin Mc Roberts (  Globally resected .  This guidance in essence  says upstream dams are not suitable for large dams. Globally resected Geophysicist  and leader in “responsible Mining” Dr. David M.Chambers has long called for an outright ban on upstream construction.

Google Earth Time Series 2003-2013 Indicates Date Placed In Service, Type of Construction, Slope and Rate of Raise

It appears though from Google Earth  photos over time that the  the  Fundao dam , the failed dam, was put on line in 2009 .   A series of google earth images show the site as virgin in 2003 and the dam completed and holding tailings in 2011.  A 2013 photo in this same series shows a dramatic raise in the dam height .

The images 2011 and 2013 clearly show a very very steep face of the dam and that it is unbuttressed.

BHP and Vale are claiming the Fundao held 50 millon cubic meters of tailings.

This indicates  a rate of deposition of 9.2 million cubic meters per annum .and an unsafe destabiliizng rate of raise of 15 meters per year.

Head Of Mine Worker’s Union  Puts Surface Area of Fundao at “10 Football Fields”.

FIFA Offical football field size varies.  At the minimum sandard ,the footprint of the  Fundao is estimated at 640,000e square meters.  It’s height at failure ( without accounting for freeboard and any accumulated water)  would be a minimum of 78 ft. (50 million of tailings/64000 meters of area)

That puts the rate of raise of the dam , including the initial starter dam which would by normal practice be at  least 20 m  at 15.6 m per year.

To reasonably assume zero pore pressure at an upstream dam (within the safe height guidelines of 30m-50 m), the  rate of raise should not exceed 4.6 to 9.2 m per year.

“. The rate of raising of the dam must be sufficiently slow such that there is a sufficient degree of dissipation of excess pore pressures in the outer shell and in the slimes, and such that excess pore pressure buildup does not occur in foundation materials. Vick (1990) suggests that, for rates of impoundment rise of between 4.6 to 9.2 m/year, excess pore pressures are usually assumed to dissipate as rapidly as the load is applied, and therefore a normally consolidated state (i.e. zero excess pore pressure) can be assumed. Mittal and Morgenstern (1976) also suggested this range as being sufficient to generate excess pore pressures in slimes.”  Martin McRobers et. al

Under the 10 point safety guidelines for upstream construction originally advanced in 1999 and 2000 and restated in this evaluation of  4 “off the shelf ” dam designs in South America  , the prototype of which had failed, authors state that a perfect score of 10 is required for safety of upstream TSF’s..

These rules exist based upon the fundamentals of soil behavior, the experience of numerous tailings dam failures and the experience of well-managed facilities that perform as intended. Of the 10 rules, a “score” of 9/10 will not necessarily have a better outcome than 2/10, as any omission creates immediate candidacy for an upstream tailings dam to join the list of facilities that have failed due to ignoring some or all of the rules”.

WISE sets the maximum rate of raise for an upstream dam at 15M/ Yr.  for dams also within height and slope limits, which the Fundao was not. Our estimates of  average rate of raise at Fundao was 15.6 m per year, just slightly above the WISE guideline but significantly exceeding slope and height attending application of ths guideline.

All Three Dams At Allegria Complex of Least Stable “Upstream Construction” Method

We are given to understand from what information is available that all three dams, in the complex  are  “upstream construction”

Upstream tailings dam construction is disproportionately the construction type of  all tailings dam failures  as compared to the safer “centerline” and “downstream” types in global data on  unplanned releases 1900-2015 and still a preferred least cost method for land deposition and retention of metal mine tailings especially at low grade mines. They are also universally recognized as the least stable type of construction especially in areas with a high seismic risk. However, best practice has generally been  that such dams should not exceed 30m to 50m so they have not, in history or in modern times been associated with catastrophic or very serious failures. A catastrophic failure generally requires an impoundment with a storage capacity of 5 million cubic meters  and a height greater than 50m.

Samarco Pushed Ahead With Expansion Without Simultaneously Creating & Having In Place Adequate Tailings Storage Capacity

In 2010 alone Samarco generated 16.1 million cubic meters of tailings waste at this mine complex.

In terms of tailings, in 2010, iron ore beneficiation in the two concentration plants generated 16.3 Mt of tailings, including sandy materials and slimes. This material was transported to appropriate waste disposal facilities (dams and waste piles), which are regularly monitored and inspected to ensure their stability. Increased waste generation has occurred due to the expansion of production at concentration plants and also due to lower iron ore grades. The sandy tailings generation rate is higher than the slimes generation rate; tailings are disposed of separately,providing better safety conditions to the dam structures and waste piles. To cope with the increase in waste generation, Samarco is developing a Tailings Disposal Plan (TDP), and “studies on tailings recycling to ensure long term business sustainability( pp4-5)



Jack Caldwell has confirmed  that Samarco specifically rejected adding a buttress to the Fundao against the advice of  peer reviewers and consultants. He says  that  Samarco was fully aware  of the magnitude of consequence of failure of the Fundao ,. but  relied on its own calculations that the probability of failure was very low against the advice of its consultants and peer reviewers.

Dr. David M. Chambers, a geophysicist and highly regarded global leader  in responsible mining , repeated his call for an out right ban on upstream  dams in the wake of the Samarco  catastrophe.

Whatever the cause, there’s no doubt the damage from both breaches would have been much less if the tailings had been less fluid, Chambers said. He co-authored a study, still to be peer- reviewed, which predicts the number of catastrophic failures will increase as miners are tempted to build larger upstream ponds in order to cut costs.

Regulators need to ban upstream construction and “wet closures” of old tailings ponds, in which the water is allowed to remain, Chambers said

Brazilian prosecutors are focusing on dam height as evidence of Samarco’s negligence.  A piping failure is shaping up as the likely cause and is one of the factors that could cause a fatal failure especially in an upstream dam of this scale.

“{Brazilian Proseutor} Cureau said Samarco was negligent for increasing the height of the dam without proper studies and failing to come up with a contingency plan, including an alarm system. She said the penalties should be severe enough that companies will understand prevention as less onerous than paying for the consequences of an accident

This all points to Samarco as on  leading edge of a “culture of innovation” in iron mine production, but “a culture of deviation” with respect to waste management practices.

Santorem Not Failed As Initially Reported But Impaired

The Santorem , initially also reported by BHP as having failed, is an older dam holding 12 million cubic meters of tailings ( no account of statements on water) .   The crest of the Santorem was recently raised with an inflatable 30 m wide rubber dam.  The installer of that dam reports at their website that the dam was at 70% capacity at the time of that crest elevation via the inflatable dam. It was also being raised at the time of failure. This suggests a built capacity of  about 17 million cubic meters  and a capacity to hold an additional 5 million of flow from the Fundau. ( not accounting for water stored or left standing on top of the tailings)

The Santorem received a large part of the release at failure from the Fundau with what exceeded  capacity flooding over the spill way into the valley below.

Confusion On Release Volume

This has lead to some confusion on   release volume. The Brazilian government and most news accounts are still citing 60  to 62 million cubic meters, the amount BHP/Vale/Samarco cited as the combined tailings content of both dams.  WISE, who receive their reports from the miner and not from independent investigation, are citing a  35 million release (that is apparently deducting from total release  the amount held by the Santorem) .  The WISE account is not clearly annotated or sourced.  It wold seen that in accordance with cstmary reporting te full amount of release from the Fundao is what should be recode as release 40 to 50 million cubic meters) and a note  or linked report explain that 5 million was held back by the Santorem.

Bowker Associates is still using  40-50 million as estimated release. ( ie not allowing for any amounts retained by the Santorem)

The Santorem since 2012 has been under “executive design” by GeoHydroTech a Brazilian engineering company under a broader engineering contract with Samarco that included  analysis of failure probabilities and damages in the event of failure.

Samarco – Mariana / MG – Contract in progress since 2012

Tailings Disposal System Mirandinha composed of Mirandinha and Santarém Dams.

  • Services provided and carried out:
  • Conceptual, basic and executive design of both dams;
  • Preliminary design construction and planning stages of construction of dams;
  • Geologic structure mapping of the area of influence of the dams;
  • Hydrological studies in general;
  • Conceptual, basic and executive design of emergency spillway system;
  • Several studies of the potential damage downstream during a possible collapse of tailings dams (Dam Break);
  • Preparation of operating manuals and maintenance of the dam.”

The photo below is from Dave Petley’s landslide blog  shows the in tact Germano Dam on the left, which was not authorized to receive any additional tailings after 2009 and the obliterated Fundao the right which was put into service c2009-2010.

photo of two dams..

Precipitated Landslide Likely Increased Force and Volume of Mud Flow That Swallowed Bento Rodriguez

According to this most competent analysis so far posits a landslide precipitated by the nearly complete release from the Fundao.    Dr Petley, an expert on landslides, theorizes that the most upstream  dam collapsed causing a landslide  which combined highly liquid tailings with the landslide  as the mass moved down to  Bento Rodriguez.  A local officer described the mud flow as 2.5 dmeters high 8 km  from the Fundao.

A very similar scenario ( although precipitated  by very heavy rains) has recently been reconstructed for a previously unreported catstrophic failure of a tailings dam in Mexico in May of 1937.  The modeling and forensic study of the tailings flow explains how the forces of the original tailings flow are exponentially increased in total force and flow volume  when a landslide is concurrently triggered.  The total flow is the combined volume of tailings contents ( tailings+water) and the landslide volume.

The term “release” as used in official reporting would not include the landslide volume in the accounting of release but would, if available,  be included it in “notes” and included in any study on the forces and total flow creating damage..  So in a precipitated landslide event, as a Samarcos Alegria complex, the magnitude of the flow and its resulting scale of damage  can be much greater than  the  damage that would otherwise  be expected from the “release” alone.

The Los Cedros Tailings dam was much smaller than either the Fundao or the Santorem, 35 m high with a capacity ( total stored volume) of 14.7 million cubic meters as of the date  of failure and precipitated landslide. It’s run out was 11 km casing 300 deaths.

Damages & Scale of Impact

The damage estimate was initially put at over $1billion by DeutscheBank Brazilian Officials, after further analysis have launched a law suit against Vale, BHP and Samarco for $us 5.2 billion.

Brazil’s biggest newspaper, Folha de Sao Paolo reports that despite this announcement the Federal Government has not been and is not present on the ground either assessing or providing relief.

Despite announcing financial assistance for the affected and declaring the incident one of the greatest environmental accidents in the history of the country, the Dilma Rousseff (Workers’ Party or PT) administration has yet to mobilize federal bodies to assist the thousands afflicted by the disaster.

During three days in the region, the only sign of federal presence observed by the news team was two Ibama cars along a Mariana road.

Lucas Ferraz & Avener Prado


Runout was initially reported  by BHP at 400KM but has pushed to 600 km at the Atlantic .

Catastrophe Occurs Against A Backdrop of Corruption &  Calls for Impeachments  Of Brazil’s President 

The headlines of Brazil’s largest paper, Fulha De Sao Paolo, are not featuring the catastrophe but continue their reporting on citizen outrage about widespread corruption, calls for reform, and petitions for impeachment of Brazil’s President..



The  Wall Sreet Journal reports that safety concerns were raised in an October 2015 inspection on contact between waste rock piles and the Fundao talings dam potentially threatening dam instability,  A Brazilian official has publicly cited this same concern and others  in a commissioned 2013 report .  The recommendations of this report were not adopted or made a condition of renewal of Samarco’s license. BHP says the waste rock pile is still in tact and that the issues red flagged in the 2013 independent assessment have been ruled out as the cause of this failureThis however does not rule out the possibility that pressure from the waste rock pile affected the dam’s stability. .


During its active life the main dam at Germano,   was raised by 2.5 meters per month  (30 m per year) which again n according T.Martin  et al.violates rule 3  of the 10 cardinal rules  of safe upstream TSF construction.

“. The rate of raising of the dam must be sufficiently slow such that there is a sufficient degree of dissipation of excess pore pressures in the outer shell and in the slimes, and such that excess pore pressure buildup does not occur in foundation materials. Vick (1990) suggests that, for rates of impoundment rise of between 4.6 to 9.2 m/year, excess pore pressures are usually assumed to dissipate as rapidly as the load is applied, and therefore a normally consolidated state (i.e. zero excess pore pressure) can be assumed. “


Dam Rehabilitation & Height Rate of Raise Presented at 2011 VanCouver Tailings Conference.

The redesign  to allow these extraordinary heights for an upstream tailings dam was presented at a major tailings conference in 2011 as a state of the art best knowledge , best engineering approach to achieving safe heights for upstream constructions even at  more than 5 times what is still widely considered the maximum safe height for such dams.

In Brazil, the method has been inspired by experience gained from the drained disposal of sandy tailings, applied for moderate heights since 1980. More recently tailings embankment with heights up to 195 meters, with the possibility to exceed the 200 meters are under construction. Examples are the two structures of Samarco Mineração S.A. at Germano Mine (correct name Alegria Mine) herein: Germano Dam buttress”

The author is closely associated with Info Mine which in turn is closely associated Dr. Andrew MacG Roberson  who is acknowledged with thanks in this paper for guidance and advice. Info Mine , created by Dr. Robertson, seeks to present  and develop and the best available work in mining and is a long term advocate for responsible, well informed self-regulation by the mining industry.

The author of the tailings conference paper and his firm were, as far as we know, not involved in the original tailings dam design  Their work was to correct some original design deficiencies and create additional capacity in the dam.  The presentation however, unmistakably suggests that the dam ,post rehabilitation per their design, was stable and suitable for the anticipated additional volume of tailings it was to hold.  It unmistakably hailed a system that makes ultra high upstream dams safe and suitable ( under comparable conditions)

This paper and this dam   has been cited in other research as evidence that upstream construction should not be prohibited and can be used  safely.even at height well above customary established best knowledge and best practice.

This rehabilitated dam and this paper have also been cited as an example that the mining industry, even in challenging times of dramatically low prices, is responding to issues of tailings dam safety not by avoiding but exceeding improved regulations and statutes such as those in Brazil 

It is  apparent now that these same departures from known best practice on the upstream dam construction were applied in the design construction and use of the newer Fundao dam which failed on November 5.

Samarco’s Rapid Expansion  Follows Metric Myth That Higher Production Volume At Low Cost Can Offset Low Grade Ore

In 2010 Samarco Mineracao ltd. S.A., the joint venture beween BHP Hilton  and Vale through which the mine is owned and operated ,described its new flow sheet to tackle it’s aggressive  plan   based on the core assumption of the mining metric: that lower grades and falling prices can maintain economic feasibility  through larger scale production at lower production costs without any additional increase in environmental security risks or potential public liability.

Although the Alegria mine was not on Bowker Assciates watch list of mines presenting the highest risk of economic and associated catastrophic environmental failure ,  it does meet the Bowker Chambers criteria for a very serious failure and keeps the global trend line to an increasing incidence of very serious failures globally on track with our prediction for 11 very serious failures globally for the decade 2010 to December 31 2019. It also exactly follows the pattern we pointed to as the major cause of such failures: dramatically increased expansions within the existing facilities and footprint of much older mines. driven by falling grades.

The decline in grades at Alegria have been dramatic and are presently estimated at between 35% and 45% while still higher than other major itabarite producers.  Brazil has been known for its exceptionally high iron ore grades and Vale, Brazil’s largest producer has been known for  iron ore grades well above global averages.

Brazil Disproprortionately Represented In Modern Mine Catastrophe’s

There are several other  cataasophic dam failures in Brazil and its mine centered state of Minas Gerais  cited in the Bowker Chambers integrated global data base of mine failures since 1910 .

Brazil is disproportionately represented globally in the count of most serious failures tailings dam failures  for this decade ending November 5, 2015 with  2 of 9 catastrophic   and 2 of 8 major failures including Germano .

Documented major dam failures failures in Brazil post 2000 prior to the November 5th Alegria  mine  tailigs dam failure  asre:

Mineracao Rio Pomba Cataguases, Mirai, Minas Gerais, Brazil, ( owned by Mineração (Industrias Quimicas Cataguases) Bauxite  catastrophic failures  jJnuary 10,2007 and January 2003;  a serious failure in March 2006

Herculano Iron Mine, Itabirite, Minas Gerais, Brazil 9/12/14 ( no details on release volume..presently cattegorized in Bowker Chambers as “serious” but description seems to indicate “Very Serious”

Sebastião das Águas Claras, Nova Lima district, Minas Gerais, Brazil 6/22/01 , categorized as “serious”

Samarco BHP & Vale All Taking Ratings Hits

Samarco Mineração S.A. is a Brazilian company engaged in the mining, beneficiation, pelletizing and export of iron ore. The firm has four pellet plants in Anquieta municipality, in Brazil’s Espírito Santo state, as well as three concentrators in its Germano plant in Minas Gerais state. It also has a port terminal in Ponta Ubu, Espírito Santo, sales offices in Belo Horizonte and Victoria, and two international offices in Amsterdam and Hong Kong. Its yearly production capacity reaches 30.5Mt. The company is owned equally by Vale and BHP Billiton. Samarco Mineração was founded in 1977 and is based in Belo Horizonte in Minas Gerais state. Moody’s revised its ratings on $2.1 b in bonds on Tuesday to what Reuters columinsit Paul Kilby described as essentially a rating of “junk” .

BHP shares slid 58c, or 2.5 per cent, to $22.70 yesterday after news of the disaster, which Morgan Stanley estimated could result in a year of lost iron ore production In their first public comments on the disaster BHP has emphasized that all responsibility and liability lies with Samarco. ( This  is the legal mechanism insulating parent companies in most of histories catastrophic dam failures  from financial liability for damages caused by failure and transferring  the lions share of  risk and costs to the public) Financial Review Columnist Matthew Sevens has asserted that Vale and BHP nevertheless have a moral obligatin to assume ful lresponsibility for damages.

Vale was elected world’s worst company in January 2012 by the Public Eye People’s, an award that refers to human rights and environment, given since 2000 by the NGOs Greenpeace and Erklärung von Bern. Vale became the first Brazilian company to “win” the award, also known as the Oscar of shame. The choice was made by public vote, and Vale received 25 thousand votes. Wikipedia proflle of Vale)

Vale , which has seen a steady and dramatic decrease in its stock price over the past year also took a sharp hit on news of the Germano catastrophic failure settling at $4.14 on the NYSE.

Quite apart from the impacts attributable to this failure both BHP and Vale have been in a major performance slide since  mid October. While also impacting Rio Tinto and CLF, both have fared better han BHP and Vale.

Since mid-October, Vale and BHP Billiton have fallen by 23% and 21%, respectively, while Cliffs Natural Resources (CLF) and Rio Tinto have plunged by 17% and 14%, respectively.

While Vale’s and BHP Billiton’s poor share price run can be partially attributed to the accident at Samarco, the demand-supply fundamentals are also to blame, haunting the iron ore equities in general

BHP Vale Perfromance Since Nid October Motley Fool

(Source Motley Fool November 2015)

A class action lawsuit has been filed on behalf of all investors who lost money because of the failure and the actions leading up to the failure. No amount is named but it focuses mainly on Vale accusing them of fraud and lies.


History of Samarco

It is important to note that Samarco was not created by BHP and Vale as a joint venture.  It was formed with its own corporate vision, its own corporate culture and its own style under the leadership of an economist and has continued in that mode throughout its life.  From the outset Samarco’s vision has required strategic alliances with other more established companies to realize is vision.

Here is the corporate history of Vale. Present Vale  corporate philosophy emerged aggressively following privatization in 1996.  Prior to that the Brazilian Government was controlling partner.  It is through Vale’s  acquisition of conroling interest in Samitri in 2000 that Vale first acquired its interest in Samarco

“in May 2000: the company acquired a 63.06% interest in Grupo Belgo-Mineira’s total equity and a 79.27% stake in the voting capital of Samitri, which in turn owned 51% of Samarco Mineração. This transaction enabled CVRD to guarantee cost savings and technological integration, accentuating the focus of its mining activities and expanding its presence on the global pellet market. Samitri, headquartered in Belo Horizonte, Minas Gerais, operated three iron ore mining complexes and was one of Brazil’s biggest producers, with annual production capacity of 17.5 million metric tons Samarco was one of the lowest-cost iron ore pellet producers in the world and it was highly competitive in the market

Alegria Catstrophe Consisent With Predictions by Bowker Chambers 2015 research on the economics of tailings dam failures. 

Other very serious failures globally since January 1, 2010 are:

Imperial Metals, Mt Polley, British Columbia, Canada

Minas Gerais,Itabarite,Brazil, Herculano

Philex Pad Cal No 3, Benquet Philippines

Ajka Alumina Plant, Kolontár, Hungary

Zijin Mining, Xinyi Yinyan Tin Mine, Guangdong Province, China

This brings the total to 6 of the 11 catatsrophic failures predicted by Bowker Chambers 2015 for the decade 2010-2019 ..

The total for catastrophic failures for the decade ending November 5 2015 (2005-2015) is   9  very serious failures .as compared to 7 for the decade 2000-2009.  We have not yet finalized our data on ore production post 2009 so do not yet have a final failure rate  bu based on preliminary estimates the rate of failure as of mid decade 2009-2019 is unchanged from the decade 2000-2009.

We will be tracking the further unfolding of details on this most recent catstophic dam failure through daily revisions to this post.

Lindsay Newland Bowker, CPCU, ARM Environmental Risk Manager

Bowker Associates

Science & Research In The Public Interest

15 Cove Meadow Rd.

Stonington, Maine 04681

207 367 5145

November 6 10 am Stonington Maine


One of the  three tailings dams in the complex  had recently installed an inflatable rubber dam.  This report at the designer/installers website indicates that at the time of installation the dam as at 70% capacity.

Dr David Petley, a global expert on landslides, has posted that he does not believe the installation or failure of the rubber dam is in the chain of events leading to failure of the two dams and the resulting landslide.

A PASTE 2013 Conference presentation by Vale ( partner in Samarco) on its exploration of TSF land deposition alternatives in Brazil:

Interesting beyond  Germano,its failure and issues attending proper design  and creation of upstream TSF’s in that p.  This was looking at how to handle the fine grained slimes that are a significant part of tailings volume in Brazilian iron mines and which are no amenable to dry stack.  Conclusion seems to be..not promising.


This report focuses on the brief perceived boom in iron  economics post 2000 and the present decade of correction and return to normal

Additional Press on Alegria Mine and Catastrophic Failure

11/5/2015  It is exciting and heartening that so much main stream global press has immediately 19sponded to and reported on this failure.  That has not been so of the world’s 1990 oher global catstrophic dam failures since 1990.  This vital work on the part of the 4th estate is essential to advancing the conversation among the many voices whose expertise is essential to fully mapping the problem of catastrophic failure and evolving a “best moment in time” plan of correction.  This dam failure, its history, and its consequence illustrate how limited the global reliance on the post Mt Polley Dam Committee Report is in addressing the global phenomenon of an increased rate and and greater scale of incidents on catastrophic failure.  The voices on that Committee are a critical part of the global conversation but each would readily say, I am sure, their commission was not mandated  to reform global mining.

Samarco reports that  two dams  collapsed “Samarco officials said on Friday the Santarém dam in the Germano complex had collapsed along with the rupturing of the Fundão dam on Thursday. The firm said it was too early to know the reasons for the disaster or the extent of carnage.

The dams had valid licenses from environmental authorities, who last inspected them in July, according to Samarco.

The dams are composed principally of sand and inert tailings, a mining waste product of metal filings.

Tailings dams sometimes hold chemicals, adding to fears of potential contamination of the nearby Gualaxo do Norte river, but Samarco said there were no chemical elements presenting health risks”

The conference presentation on the buttress work refers to the  dam as  “the main dam” and not by the name “Sanatrem Dam” so not clear whether the same structure. The scale of damage described and photographed however suggests  that the Sanatrem Dam is te same dam referred to as “Germano Main Dam”.  Dr. Chambers & I learned in our research for Bowker Chambers 2015 that it takes a very long  time to get a complete story on any failure and we continually find new information even on much older catastrophic failures.

At this stage after a major failure all information is just what has been observed and reported and it is normal for details to be confirmed slowly


This is a really superb local account giving great details on the political and legal background to the failure

This excellent  piece by Jim Regan and Susan Taylor looks at the failure in the context of global issues on dam failures, to policy, to the need for comprehensive solutions and to the reality of technology gaps

This post adds further details on recent inspections of both dams and additional quotes from the miner and government

There are four Samarco dams: Germano, Fundão, Santarém and Cava Germano. The company says all four have operating licenses granted by the regional environmental authority.

The last government inspection took place in July 2015 and indicated that all four of the dams were safe, the company said. Samarco also performs its own inspections, as required by the federal law on dam safety. The 12:00 am shift operations team is expected to report maintenance conditions and identify any abnormality immediately.

Vescovi said the mining company does not yet know why the dams collapsed. “We appreciate the help of the society and the expressions of support that have been directed to those affected by the disruption of the Fundão dam and Santarém,” he said.

Brazil’s President Dilma Rousseff said the government will investigate the causes of the dam collapses and identify who is responsible for the disaster”

This post asserts that geosynthetics can play a role in TSF stability and performance. ( They had no information on such uses at the two failed dams in Germano)



This 2002 Martin/McRoberts Technical Paper presents an advocacy for the USA method of dam stability analysis citing examples of major failures where an ESA centered design was the cause.   This is more than a little beyond my  expertise but Martin & Mc Roberts are saying the main difference has do with fundamental assumptions about propensity to shear under static loads ( ie not precipitated by eartquakes or other external forces).  At its core the confusion is over whether  whether slimes are assumed to be frictional ege like sands) or cohesive ( eg  like clays.)

In Martins Mc Roberts own words:

The advocacy of USA for upstream tailings dams presented in this paper is therefore a well known approach, best supported by Carrier’s (1991) back analysis of the well known Tyrone failure case history. The Tyrone failure provided a classic example of the misconceptions as to tailings strength. This seems to have its origin in the old soil mechanics precepts that sands were frictional and clays cohesive. The misconception is that if one has non-plastic rock flour such material is obviously frictional and an ESA analysis applies. The flawed corollary is that if slimes are not cohesive, then a USA is not required – irrespective of whether or not the slimes are contractant in shear, and potentially liquefiable. Given these misconceptions, it is not surprising that tailings dam failures continue to occur.These lessons, shorn of theoretical aspects, were well understood many years ago by the likes of Casagrande and MacIver (1970), Smith (1972), and

Lenhart (1950), and yet still have not entirely permeated the practice of tailings dam design and analysis.”

ESA analysis typically overestimates the factor of safety by a factor of two relative to USA analysis. This in turn would suggest that a great many upstream tailings dams have USA factors of safety of less than one (since they are rarely designed using ESA to a factor of safety of 2 ormore), and should have failed (based on limit equilibrium analysis), but have not.

One of the numerous triggers listed that may be most relevant in the case of Samarco given what we know so far is the rate of raise and/or construction activity at the crest.

Overloading due to: rapid rate of impoundment raising

steepening at crest

construction activities at crest

Critically important in evaluating the Samarco falure is that traditional guidance on assumed zero pore pressure at rate sof rise of between 15ft t 30 ft per year applies when the height is 35m or less.

Use of both ESA and USA requires an estimation of the effective consolidation stresses at any

given time, which in turn require a good understanding of the pore pressure conditions (hydrostatic versus downward drainage, normally consolidated versus excess pore pressures) within the dam.

Pore pressure conditions within upstream tailings dams are very often complex, misunderstood,  and improperly incorporated into stability analysis. Misinterpretation of piezometer data can easily occur if adequate piezometer coverage does not exist. Vick (1990) suggests that, for rates of impoundment rise of between 15 and 30 ft/year, excess pore pressures are usually assumed to dissipate as rapidly as the load is applied, and therefore a normally consolidated state (i.e. zero excess pore pressure) can be assumed. Mittal and Morgenstern (1976) also suggested this range as being sufficient to generate excess pore pressures in slimes. The authors caution that these experience-based criteria on rate of rise can be safely applied only in cases with good underdrainage (permeable foundation relative to the tailings slimes), relatively smaller embankments (35 m in height or less) with relatively short drainage paths, and slimes free of significant clay content and plasticity. For example, the authors are aware of one large upstream dam in which very high excess pore pressures exist in the clayey slimes despite a rate of rise of only about 7 ft/year. Another example that emphasizes the need for caution is the Tyrone tailings dam, which failed under undrained conditions at a construction rate of 12 to 15 ft/year.”

 Cautionary tale against use of off the shelf designs  Another Martin McRoberts Paper on Upstream Dam Construction

“. When designed with sound engineering principles and constructed and monitored with observation of those principles,this economical advantage can be realized without compromising the stewardship requirements of modern tailings  management.”

“This paper briefly describes four upstream tailings dams. These four dams together offer a somewhat unique case history because they all share an essentially identical design. All four serve base metal mines (with very similar ore mineralogy and mill grind) operated by the same mining company, located at high altitude, relatively dry locations in South America. Due to differing site conditions and operating constraints, however, the single design (and the common operations philosophy) led to four different outcomes.”

The prototype failed leading to an evaluation of the three other identcal dams at the owners other mines in South America.

The design of the dams was prepared by an internationally known and respected

design-consulting firm in the 1990’s, a time when the requirements and engineering principles

for safe tailings management are well understood. The design essentials are illustrated in

section on Figure 1, and incorporates the following key elements:

Starter dam about 10 m to 20 m high, constructed of granular alluvium with filter

and drainage zones to ensure the starter dam would function as a toe drain.

Upstream raising of the dam at an overall 3H:1V slope, to a height 20 m to 25 m

above the starter dam crest elevation.

Requirement for maintenance of a minimum 30-m wide beach above water separating the dam crest from the decant water pond, at all times(BAW)”

 “Design” phreatic level assumed by the designer at any location within the dam

section to be at the ½ height of the dam, with hydrostatic conditions assumed


From their collective experiences with dozens of upstream-constructed tailings dams,

the authors propose 10 rules of upstream tailings dams as outlined below. The authors have

presented these previously (Martin and McRoberts, 1999, Davies and Martin, 2000) but

restate these fundamental and essential rules herein to provide context for the performance

and assessment of the four dams that are the subject of this paper”

(Under authors 10 essential principles a perfect 10 is required..omission of any one factor can lead to failure)”

These rules exist based upon the fundamentals of soil behavior, the experience

of numerous tailings dam failures and the experience of well-managed facilities that perform

as intended. Of the 10 rules, a “score” of 9/10 will not necessarily have a better outcome than

2/10, as any omission creates immediate candidacy for an upstream tailings dam to join the

list of facilities that have failed due to ignoring some or all of the rules”.

(Rule # 3 on rate of rise is what seems most at issue  not just in upstream dam failures but others as well:  the rate of rise:)

“3. The rate of raising of the dam must be sufficiently slow such that there is a sufficient

degree of dissipation of excess pore pressures in the outer shell and in the slimes, and such

that excess pore pressure buildup does not occur in foundation materials. Vick (1990)

suggests that, for rates of impoundment rise of between 4.6 to 9.2 m/year, excess pore

pressures are usually assumed to dissipate as rapidly as the load is applied, and therefore a

normally consolidated state (i.e. zero excess pore pressure) can be assumed. Mittal and

Morgenstern (1976) also suggested this range as being sufficient to generate excess pore

pressures in slimes. The allowable rate of rise of 1 m/month specified for the design shown on

Figure 1 therefore appears in violation of this rule.”

The rate of rise at Germano main dam was 2.5 meters per month according to the 2011 Tailings Conference presentation on its reconfiguration.

10. If an upstream constructed dam is raised at a slope steeper than 4H:1V, the

likelihood of a static undrained failure due to minimal trigger is increased. Accordingly,

upstream dams should be raised at slopes of 4H:1V or flatter

Case study # 2 sounds very much like the main dam at Germano..  a butress was added to stabilize emerging  pore pressures

Because the tailings in the impoundment have a relatively high pyrite

content and are potentially acid generating, it had been recognized two years prior to the

remediation that clogging of the geotextile enclosing the finger drains below the starter dam

could develop due to formation of chemical precipitates generated by oxidation reactions.

The geochemical processes underlying this mechanism are described by Plewes and

McDonald (1996). Upon cutting of the geotextile at the finger drain outlets at the downstream

toe of the starter dam, clogging of not only the geotextile but, to some extent, the drain rock,

was indeed noted.”

Swedish License Thesis looking at Mathematically modeling stability enhancements  to upttream tailings dams anticipating greaer rate of raising that is normally considered safe



While not a complete strategy for preventing catastrophic dam failures, the West Australia Mine Regulations are state of the art globally.  Here are therir guidelines for tailings dams.


( Included this because of reference in one article post collapse that the failure occurred or was just after installation “of a a rubber cap at the dam”   As a Risk manger, from a Risk Manger’s poin tof view the use of untried, unproven technology in high risk situations is only o.k. where the risk is already present and there is no known proven solution.  In mining there is a continual push to allow unproven systems even in ultra high risk situations where a failure would create that risk..  This application proposes use of geosynthetic membranes in lieu of  engineered soil and rock layers that would normatively be used.

Conventional Wisdom & Cautions on Upstream Tailings Dams

This 1979Klohn basic  guidance on upstream tailings dams is not much changed in the late work by Morgenstern, Vick, Davis & McRoberts

Chinese Study of Ultra of Stability of Ultra High Tailings Dams Under Different Conditions

This is a case study of  centerline dam, China’s largest  with an 800 million cubic meter capacity and a design height of 20 meters.  It finds that while the design under normal working conditions , it cannot attain the specified coefficient of sfatey under conditions of saturation.

Centerline construction is safer than upstream configuration for any holding of tailings.Downstream construction is recommended for very large dams but space constraints, costs, and local availability  of materials  centerline construction is  most often used for modern large dams.

At Mt Polley, deviation from the Knight Piesold design due to non availability of suitable materials resulted in what was essentially an upstream design also violating upstream construction standards..Mt Poley was, though within accepted height guidelines for an upstream dam at approximately 60 meters.  The dam committee investigating cause of failure found that a buttress recommended by the Ministry of Mines would have prevented the failure if Imperial had acted in time.

Posted in alegria mine, Analysis TSF Failures, BHP, Bowker Associates Science & Research In The Public Interest, Brazil 's High Grade Iron Ores, Causes Of Catastrophic Tailings Dam Failures, Center For Science in Citizen Participation, David M. Chambers, Dirk Van Zyl, Frequency of TSF Failures BY Decade, Geoesteval, Germano Tailings Dam Failure, Height Limits of Earthen Dams, Lindsay Newland Bowker, mine Company Valutaion, Mine Feasibility, Mine Risk Management, Mining Economics, Mining Environmental Crimes, mining environmental risk management, mining public liability, Pimenta De Avilar, Rate of Raise for Upstream Tailings Dams, Risk & Public Liability of Tailings Dams, Risk Economics and Public Liability of Tailings Dam Failures, Samarco Environmental Crimes Investigation, Samarco Mineracao S.A., Samarco Tailings Master Plan, Samitri, Tailings Dam Risk Management, Upstream Tailings Dam Safety, Vale SA. | 4 Comments

Tailings Facility Failures 1915-2014: An Integrated/Reconciled Compilation of ICOLD Bulletin 121 and WISE Supplemented by Carefully Vetted Compilations

A major work product of Bowker Chamber 2015 ( Risk-Public Liability-Economics of Tailings Storage Facility Failures” Bowker & Chambers, July 2015,) this downloadable excel of the data base we created for all authoritatively reported Tailings Facility Failures 1910-2009 is the most complete compilation known .

Dr. David M. Chambers ( Center for Science in Community Particpation) & Lindsay Newland Bowker ( Director, Bowker Associates Science & Research In The Public Interest)   are pleased to be able to share this machine readable compiilation with other researchers and to invite collaborative input to it to fill  gaps that still remain and add failures never reported.  Recently we discovered a 2007 catastrophic failure in Minas Gerais  that had not been previously reported at WISE.  It finally turned up at WISE 8 years later.

We found authoritative compilations of events in the Phillipines, Chile, and China that were not reported in WISE and were not included in ICOLD Bulletin 121 ( a global  compilation by survey through 2000).

A key attribute of our compilation is the severity rankings which are shown numerically and by color code.  The criteria governing these codes were total release, run out, and deaths.  Another key feature of our revised data base is identification of the event by correct  mine name . parent company, and subsidiary/operator.  That this protocol is not part of the WISE and original Bulletin 212 ICOLD compilations was an initial obstacle  not only to eliminating duplicates and identifying repeated occurrences at the same mine.  Not having correct mine name and parent company also hindered other research on the mine and the economic/financial circumstances leading up to failure.

We are collaboratively tracking, vetting and compiling authoritative data on post 2009 failures and  still filling in missing data on pre 2010 events.

We  hope to post annual updates to our compilation.which will also review trends and next decade rpedictions..  Based on data through December 31, 2014 we are still predicting 11 catatastrophic tailngs facility failures for the decade 2010-2019 at a cost of $6 billion globally.

Please forward all updates, additional data, additional information to Dr. Chambers and copy us at

David M. Chambers <>

Posted in Bowker Associates Science & Research In The Public Interest, Center For Science In Public Participation, David M. Chambers, ICOLD BULLETIN 121, Lindsay Newland Bowker, Tailings Facility Failures 1910-2015, Tailings Failures Globally By Seveeirty of Failure, WISE URANIUM DAM FAILURES | Leave a comment

Yellow Giant Mine Failure : Canada’s Flailing Against Declining Grades and Rising Production Costs

At its heart the Yellow Giant Mine failure which Van Couver Sun journalist Gordon Hoekstra, thankfully and with good research, is keeping front and center is about an improperly vetted and proven use of  pre-concentration technology.  The asset had not been proven as a resource at the time of approval by BC MOM and the selection of  pre concentration process technology was based on limited sampling .  The selected DMS concentration, is a relatively costly system which produces actual wet tailings slurry .  ( This link is to Vancouver Based Sepro Systems.  Their system has not been named as the system in use at Yellow Giant)
Sudbury 2011, an annual mining conference on innvoations in mining, featured pre concentration as  a possible approach to Canada’s mining crisis of tumbling grades and rising production costs calling on Canadian Miners to be more bold and forward thinking in the to create a “culture of innovation”  Sudbury 2011 correctly pointed to pre-construction as worthy of more attention in Canada for mine expansions , de novo mines,  underground mines unable to expand  within existing and those not able to provide concentrate at global market standards.. It offers the possibility of all that was focused on at Sudbury 2011 but the publicity it has gotten in Canada through the Yellow Giant Mine failure and stop work order does not serve the technology and its possibilities for Canadian mine problems well.
“Best Practice’ almost by definition requires  both “best knowledge” and “proven efficacy”.  Best Practice is not at all inherently incompatible with the call to innovation made at Sudbury 2011 on behalf of Pre-Construction.
But that does not appear to be  the story at Yellow Giant Mine.  What happened there is more like the “try it any way it might work” mentality of  the U.S. A’s  well funded and very influential mining industry/extraction industry lobby,   ITRC.  ITRC actually “trains”  state regulatory  personnel in the use of unproven technologies and requires a cult like pledge of State Agency members  to allow and promote them in mine expansions and de novo mining .
Proven Efficacy & Customary Place of Pre-Concentration
Pre-Concentration is a method of separating up to 50% of the non ore bearing wastes underground before hoisting to the surface for finish processing.  The separated non ore bearing underground waste in most ystems directy bacfills as produced, That reduces the throughput volume ( what goes to the mill for finish processing to concentrate ) by 50% as well  and  elevates both the concentration of ore in the concentrate and also the overall grade of the concentrate viz global standards while minimizing the above ground footprint including the footprint of an existing TSF.
It’s proven efficacy, according to the pre-concentration sector is both to improve margins ( ie make a mine economically feasible that might not otherwise be performing)’s an extra step in the process of creating a final marketable concentrate meeting global standards.   The system at Banks Island committed to deliver concentrate at AU56g/t gold, well above what is normally achievable without pre concentration.
In its more customary uses pre concentration  at a site also producing concentrate would then still have a tailings residue at the end of the process and would still need a tailings management plan for that waste, essentially the other 50%.
Backfill at Yellow Giant Apparent Source of Pollution
Backfill deposition and evaluatin of materials is as much an issue in pre concentration systems as in any other backfill.  Yellow Giant has 5% total sulphur and has very high arsenic and is therefore potentially acid generating.

Thus, backfilling of underground workings is

often regarded as best practice for the rehabilitation of mining voids (e.g.,

MEND, 1995). Such backfilled waste is often regarded to be as chemically

and physically secure as the original mined ore. In particular, the disposal

of tailings below the groundwater table reduces the amount of reactive

material that would be available for oxidation. Nevertheless, if the tailings

are stored above the groundwater table without a dry or wet cover,

oxidation may generate metal-rich acid leachate (Morin and Hutt, 1997).

The leachate in most cases will be transported in the saturated zone of

surficial aquifers where the prevailing groundwater flow will produce metal

and metalloid rich plumes down gradient from the mine workings (e.g.,

Warren et al., 1997; Younger, 2000). This study is based on seasonal

groundwater measurements and sampling and the results of kinetic leaching

experiments in combination with hydrological modelling. ”

System designs directly dispose of wastes as generated out of the  sorting system  as produced.

The B.C. MOM stop work order requires submission and approval of a waste management plan. The February 2013 technical report by Baldwin, now posted up at Banks Island’s website does not address or describe the specifics of the back fill/ separated waste materials.

Here is an excellent study exploring the efficacy of pre-concentration in mafic ores at several mines in Sudbury struggling wiith declining grades and rising costs..  This is the “culture of innovation” Sudbury 2011 pointed to and the level of work  that should attend any mine expansion or attempted save.
Yellow Giant Mine Deviation From Proven Applications of Pre-Concentration
At Yellow Giant Mine there are no details in the NI 43 101  on Yellow Giant Mines’ “scheme” nor have we found any other  sources with details on the  management plan for the 50% that stays underground and is usually directly applied as backfill.  It is materials of a uniform pre specified size and contains all the same minerology except lower levels of the targeted ore .  So its geochemical and metal profile is unaltered . Without pre concentration all would have ended up in tailings above ground after mill throughput.
The permit at Yellow Giant Mine did allow the underground deposition of the pre separated waste from pre concentrated ore but we have no details on any pre testing that was done on the waste stream or underground deposition plan.  The NI 43-101, which offers the best overall summary of history, study, mine pan etc.  also offer no details on that part of the plan dealing with the pre-concentration waste and its management. It does though characterize the entire scheme as “possible” based on lab tests viz the production of pre-concentrate .  It also repeatedly emphasized that the asset itself was not a proven resource based on all drill core and analysis which existed as of the time of the  permit application and fund raising via TSX.
The Fiscal Acrobatics of the Yellow Giant Mine Plan
The Gold’ Report’s Louis James, a specialists in promising pecative gold ventures is an investor and promoter of the Yellow Giant project calling it the “little mine that could”
The original Yellow Giant Mine version of Pre-concentration was to ship the pre -concentrate to Nevada. ( Imperial Metals acquired the Yellow Giant Mine asset in 2009 along with Ruddock Creek and also owns an asset in Nevada.  The destination smelter was not named.  Banks Island Gold leases from Imperial who have not been confirmed to have any direct role in operations or control).  It appears that in stead Banks Island entered an offload agreement with a small  NY  commodities broker, Metallica Resources Ltd.  The agreement required delivery monthly to them of a certain volume of concentrate grading not less than  AU56g/t.  Banks Island announced its proof of success in producing “marketable concentrate” claiming a  “realized price of $1,493” and a grade of AU67g/t.
 Feasibility assumes gross revenue ( before costs) to be 80% of market price.  A market price of $1360 was specified as the minimum for financial feasibility.At the time of the report the price of gold was briefly at $1,700 per oz.
According to the February 2013 NI 43-101 the , the Bob Zone, the main focus of the extraction plan , had total sulphur level of 5.0% & and high arsenic levels in new samples analyzed in 2011 and 2012..  It required a mill capable of handling the high arsenic.   Global arsenic standards are 0.5%  for concentrates. Excess of this level have price penalties  or will not be accepted at all .
At the time B.C. Ministry of Mines approved this permit the global price of gold was around $1,095/oz. .At the time the Imperial Metals subsidiary announced its success in producing a marketable concentrate the price of gold was already below the level required for financial feasibility at $1,200.
B.C. Ministry of Mines and Environment Canada Co-Responsible for Yellow Giant Mine public will bear whatever Costs there are for damages
The level of financial risk the B.C. Ministry of Mines and Environment Canada seems to be willing to tolerate in its struggle to overcome 70 years of below world average head grades and rising production costs will very clearly exponentially elevate environmental security risks if this “culture of innovation” doesn’t  also require careful vetting of both financial and environmental viability.
Further Reform Needed At TSX
It is important to note that the TSX bears some scrutiny as well.  Should a non proven resource even be allowed to raise capital in public markets for other than exploration and feasibility? This group ( the Board of Yellow Giant Mine) raised $25 million for an actual mine operation for a resource that wasn’t even proven.   Recently the stock was trading at 0.02 so presumably those investors are out that $25 million.  It is clear from the financials of this group that any correction or clean up will be entirely at the publics expense.  ( There are no details available on closure security, if any)
See notes below on corrections and retractions TSX require to the Yellow Giant NI 43 101/
They still allowed TSX listing for operations and production for an unproven resource. Id this allowed on the American or NY exchanges?
August 5, 2015 Stonington Maine
Lindsay Newland Bowker, CPCU, ARM Environmental Risk Manager
Bowker Associates
Science & Research In The Public Interest
February 2013 Banks Island announces production of marketable concentrate.”Gold concentrates, representing 55.4 tonnes, averaged 66.7gpt Au, 286gpt Ag, and 6.7% Cu. The minimum required quality for gold concentrate under the off take agreement is 50gpt Au.” off take agreement is  with Metallica Commodities Corp.  The price was $1,200.  $1300 plus was needed for financial feasibility.
July 31 2015 Gitxaala Leaders say they never approved the mine ( which is onheir unceded lands) and that it as affected harvest areas important to the Gitxaala people.  Banks Island refuses to obey shut down order.
Harsh Commentray and supporting data on Banks Island Financials  criticism of promotion of mine as a good investment
Retractions & Correctpns to Ni 43101 for Yellow Gant that were non compliant
Banks Island Gold Statement on Shut Down Order & Circumstances Prompting It
“It is notable that the Yellow Giant project has no surface storage of tailings. Banks Island Gold Ltd. is one of the only operators in the world that is successfully operating a Dense Media Separation (“DMS”) plant to pre-concentrate a primary gold ore. Pre-concentration rejects up to 50% of the mined mass in a coarse gravel sized product resulting in sufficient void space in underground workings to dispose of all tailings underground. “
North American Broker offering quick settlement on gold and silver concentrates .  Crest One has not been identified as in anyway associated with the Yellow Giant/Banks Island  project.  provided as general background on  trade and markets in gold and silver concentrates. BCGold Corp. (BCG.VNews)(BCGOF.PKNews) (or the “Company”) is pleased to announce that it has entered into a concentrate purchase agreement (the “Purchase Agreement”) with Auramet Trading, LLC (“Auramet”), a New Jersey-based precious metals merchant, to facilitate the sale of approximately 0.8 dry metric tonnes (dmt) of gold-rich gravity concentrate produced during bulk sampling at the Engineer Mine in 2011. Auramet has arranged a secondary agreement between BCGold Corp. and Sipi Metals Corp. (“SiPi”), a precious metal refinery situated in Chicago, Illinois, with respect to refining terms and treatment charges for the recovery of gold and silver from the concentrate.”
 In April 2015 Yellow Giant reached definitive purchase agreement for silver with Silver Stream  SECZ
Posted in Bowker Associates Science & Research In The Public Interest, Canadian Mining, Gordon Hoekstra, High Total Sulphur, Imerial Metals, Lindsay Newland Bowker, Mine Risk Management, Pre Concentration, Public Liability & Financial Risk, Sudbury 2011, Tailings Risk Management, Yellow Giant Mine, Yellow Giant Mine Failure | Leave a comment