Rio Tinto: the River, the Mine and the Corporation Still Polluting After All These Years

(5,000 Years Later, That Is)

Gary G. Kohls, MD

The Rio Tinto mining corporation is a British/Australian transnational mining corporation that is  the second largest mining company in the world. It is a close second – in terms ranking in the Forbes 500 – to the biggest, the British/Australian mining corporation BHP Billiton (considered the 19th worst polluting corporation in the world).

BHP Billiton was responsible for Brazil’s largest environmental disaster in history when, on November 5, 2015, two of the dams encompassing its toxic tailings ponds burst, suddenly releasing uncounted millions of tons of poisonous slurry into the Rio Doce river (ironically, doce means “sweet” in Spanish), killing all aquatic life downstream and wounding many local people. The huge amount of poisons suddenly released have likely permanently polluted the waters of the once drinkable and fishable 300 mile long river all the way to the Atlantic Ocean).

Brazil’s Rio Doce after the BHP Billiton disaster 2015
Brazil’s Rio Doce after the BHP Billiton disaster 2015


Incidentally, BHP Billiton is one of the 90 largest corporations in the world that extract and market fossil fuels and are responsible for 2/3 of the greenhouse gas emissions that have been altering the earth’s climate and polluting its air, water, soil and animal and plant life since the beginning of the industrial age.

The History of Rio Tinto Copper Mining

After Rio Tinto purchased the mining rights to large portions of copper-rich southwest Spain in the late 1800s, the English mining corporation named itself after the river that flows out of the area, which contained one of the largest pyrite (pyrite = “fools’ gold” = iron disulfide [FeS2]) sulfide deposits in the world. The area that was damned to become Spain’s most polluted area is called the Iberian Pyrite Belt (IPB). Over the centuries, the IPB attracted a number of exploitative corporate entities, including the Roman Empire, because of the raw copper and high grade copper ore, as well as the occasional silver and gold deposits (from which the Romans cast some their earliest coins).

Incidentally, Tinto in Spanish means “tainted” (not “red”) after the highly contaminated (with toxic minerals and sulfuric acid) and multicolored (usually red from dissolved iron oxide) hues that discolored the toxic water emanating from the underground and open pit copper/iron/manganese sulfide mines that had been active off and on for thousands of years.

The Rio Tinto watershed and estuary was once, before Christopher Columbus set sail from the river in 1492 and for several centuries prior to the era of open pit sulfide mining, a thriving commercial fishing area, but ever since the mining corporations began exploiting the area (with open pit mining techniques), the estuary fed by the Rio Tinto no longer has any fish or other aquatic life in it. And offshore, in the Gulf of Cadiz, the only commercially viable fishing today is for small migratory fish like sardines and anchovies.

Water Downstream From Rio Tinto Copper Mine Has a pH of 2!

The Rio Tinto, despite attempts at governmental remediation over the past generation, people still can’t drink the water, only partly because the water in the river has a dramatic acidic pH of less than 2, which approximates the acidity of stomach acid. Chemical burns are guaranteed if human skin or mucosa is exposed to the water even for a brief time. The river water is infamous for being able to dissolve iron.

But acid water isn’t the only reason that the water can’t be used, for the Rio Tinto is also one of the most chemically polluted watershed systems in the entire world. But it wasn’t always that way. One can thank the inherent dangers of sulfide mining for its demise.

The Rio Tinto today, thanks to Sulfide mining
The Rio Tinto today, thanks to Sulfide mining


Poisoned watersheds, including both surface water and aquifers near either underground or open pit mining, are inevitable and are also likely to be totally irremediable forever, no matter what is said in the carefully scripted corporate talking points that seem to be so convincing to naïve politicians and bureaucrats.

An Ounce of Prevention is Worth a Pound of Cure

Below are some sobering facts of history and science that should convince non-gullible readers of this column to become increasingly engaged in the current PolyMet and Twin Metals debates over whether or not the DNR, the EPA, the US Forest Service, the Governor’s office, the legislature, the media, the IRRRB, etc should even consider allowing sociopathic, foreign corporations to experiment with Minnesota’s pristine environment.

Copper/sulfide mine-contaminated Super Fund sites that occur near lakes, streams and aquifers can never be remediated no matter how many billions of scarce tax dollars are thrown at them or how many millions of dollars are theoretically set aside for the inevitable future catastrophic tailings pond ruptures. The few temporary jobs “promised” by the sociopathic corporations will not be given to the vast majority of northern Minnesota miners. There are less risky ways to create jobs.

Below are excerpts about Rio TInto’s nefarious history, to me the company is the poster child of the multinational copper mining industry. Knowing about Rio Tinto plc should tell us all we need to know about copper mining.

The excerpts come from the September 2000 edition of the University of South Florida’s Scholar Commons.


“The Rio Tinto Estuary: 5000 years of Pollution”

By R.A. Davis Jr. et al.

Posted at:



The Rio Tinto system in the province of Huelva, southwestern Spain, has great historical significance as well as environmental interest. It is one of the most polluted fluvial-estuarine systems in the world and most likely has been so for thousands of years. It is in the headwaters of this river that mining supporting the Copper Age and Bronze Age took place. The estuary….was the origin of Columbus’ expedition in 1492 and for subsequent trips. Most recently, the city of Huelva has become the site of one of the most polluted industrial areas of the world….

The massive sulfide deposit called the Iberian Pyrite Belt is one of the largest and most famous of such deposits in the world.

Historical perspective

Mining of these massive sulfide deposits has been going on for about 5000 years, beginning with the Iberians and Tartessans who developed the first mine about 3000 BC….This underground, small-scale operation was followed by that of the Phoenicians and the Romans. The area is the site of the beginnings of the Copper Age and the Bronze Age and the Romans made some of their first coins from materials mined here, especially the silver and gold….

….in the nineteenth century the mining was taken over by the United Kingdom, and large-scale, open-pit operations prevailed until the deposits had been essentially depleted about a century later. Peak production for the large volume products such as pyrite was between 1875 and 1930….The expansion of the mining to open-pit methods led to the total production of about 1600 million metric tons of (waste) material….

Water quality of this estuary is extremely poor with low tide pH values typically at 2.0 – 2.5….The only organisms in the river portion of the system are microalgae, bacteria and fungi…Shell material is conspicuously absent from the surface sediments of the estuary….

Important pollutants included in the analyses are Iron, Titanium, Barium, Nickel, Cobalt, Chromium, Vanadium, Zinc and Copper [Fe, Ti, Ba, Ni, Co, Cr, V, Zn and Cu]….

….recent investigation of heavy metals was undertaken for 12 sites from the mine area to the mouth of the estuary. These studies all concluded that there were quite elevated concentrations of many heavy metals (e.g. Lead, Cupper, Calcium, Manganese, Arsenic, Zinc, Iron, Silver [Pb, Cu, Ca, Mn, As, Zn, Fe, Ag]) in the estuaries as a consequence of the mining activities….



And below are excerpts from a 2015 journal article from Environments 2015, 2, 295–316.

It is posted at: and titles:


“Background Conditions and Mining Pollution Throughout History in the Río Tinto”


By Manuel Olías and José Miguel Nieto - 26 June 2015


From the Departments of Geodynamics, Palaeontology and Geology, University of Huelva, Campus “El Carmen”, 21071 Huelva    




The Río Tinto drains the eastern part of the Iberian Pyrite Belt (IPB), an area with a huge amount of massive sulphide deposits that has been mined for the last 4500 years. This river presents extreme conditions, with very high concentrations in solution of metals and metalloids and low pH values. Mining activities in the upper part of the watershed of the Río Tinto have been documented since historical times and a huge amount of widespread acid-producing mine residues exist in this area….


Here we show, using numerous geological, archaeological and historical records, that the present quality of the Río Tinto is the result of mining activities, especially during the period 1850–2001….


Acid mine drainage (AMD) is one of the biggest environmental problems associated with the mining of sulphide-rich mineral deposits, being responsible for the pollution of surface and groundwater in the vicinity of mining areas. AMD results from the oxidative dissolution of pyrite together with other less abundant sulphide minerals (pyrite (iron disulfide = FeS2) with chalcopyrite (copper iron disulfide = CuFeS2), arsenopyrite (iron arsenic sulfide = FeAsS), sphalerite (zinc sulfide = ZnS) and galena (lead sulfide = PbS)….generally associated with metal-bearing mineral deposits. Its generation is the result of the exposure of sulphides to air, water and microorganisms, and involves complex processes governed by a combination of physical, chemical, and biological factors, as has been recently discussed in a review of the current state-of-the-art of AMD. Sulphide oxidation occurs naturally in the zones where these minerals are in contact with the atmosphere; this is known as acid rock drainage. However, under natural conditions, most of the sulphides remain buried under anoxic conditions and only a small fraction outcrops and is exposed to the action of oxygen and water. Mining activities enhance the generation of acidic leachates because they increase the exposure of sulphides to air, water, and microorganisms by: crushing of the sulphide-rich rocks increasing the surface area exposed, drilling tunnels and galleries that allow atmospheric oxygen to come into contact with buried sulphides, depressing the water table, etc. In many mines, once extractive activity ceases, increased concentrations of contaminants in the water are produced due to the recovery of groundwater levels and the re-dissolution of many salts precipitated in the unsaturated zone. Subsequently, the concentrations decline but can still stay elevated for hundreds and even thousands of years….


The IPB contains one of the greatest concentrations of polymetallic massive sulphide mineralization on Earth….


No fish, amphibians, insects or plants live in this river of acid waters….


In this area, there is a startling landscape without vegetation and with large reddish spoil heaps, huge open pits…., former industrial facilities for mineral treatment. These residues generate leachates with values of pH close to 1 and dissolved concentrations up to 84,000 mg/L of sulphate, 35,000 mg/L of Fe, 104 mg/L of Arsenic, etc….


Downstream of the mining area, contamination content decreases owing to dilution with water of uncontaminated tributaries joining the main course and attenuation processes. However, pH values remain at around 2.5 due to buffering by the ferric iron precipitation. Before its mouth in the estuary, the Río Tinto still has a high level of contamination, with average pH values close to 2.5….


The Río Tinto, along with the Río Odiel, carry huge amounts of dissolved pollutants to the Huelva estuary: 7900 tons/year of iron, 5800 tons/year of aluminum, 3500 tons/year of zinc, 1700 tons/year of copper, etc. This, together with the industrial pollution, makes the Ría de Huelva one of the most polluted estuaries in Europe, with high metal concentrations in waters and sediments.between 1850 and 1886 the Río Tinto suffered a major degradation.…“This coast has been very abundant in oysters and other mollusks, everywhere, but for some years has been reduced to nil production….”

The Valley of Lucifer


.large toxic clouds of sulphur fumes containing arsenic, that caused serious damage to crops and forests due to acid rain, as well as diseases and increased mortality of the inhabitants. In Río Tinto mine, sulphur gases reached 500 tonnes per day, so the area became known as “The Valley of Lucifer”.


The complaints of the population due to the bad working conditions were suppressed, resulting in a massacre in 1888….


the generation of huge amounts of hydrometallurgical waste, must have led to a further deterioration in the conditions of the area, above all in the Rio Odiel basin where the tailing dams of Cu and gossan (iron oxide = rust) are located….


An important industrial complex was developed in the estuary of the Ría of Huelva from 1967 contributing to the contamination of the estuary. Since the 1990s, the environmental authorities are making major efforts to reduce this type of pollution and the conditions in the estuary are improving. However, there remains a big problem due to contaminants from mining carried by the Tinto and Odiel Rivers….


5. Conclusions


Pollution in the Río Tinto has paralleled the history of mining….


….due to the longevity of the processes of acid mine drainage, acidic leachates are still produced in the old Roman mines affecting areas of the headwater of the Río Tinto. Until 1850, the water between the Peña del Hierro and Lago Cave, and also in the lower reach of the river and in its estuary, was of good quality.…


….In the late nineteenth century, with the arrival of foreign investors and the major mining boom, the total degradation of the Río Tinto occurred, as with many other rivers in the IPB. Pollution levels increased significantly in parallel with mining intensity, reaching a similar state as today. Due to the high toxic concentrations of elements entering into the estuary, loss of rich fishing at the Ría of Huelva also occurred….the recovery of the Río Tinto would require enormous economic resources.


Joe Hill and Utah’s Copper Bosses

The most important thing for 1) aboriginal people who want their sacred land, water and wild rice preserved for the next 7 generations, 2) environmental activists concerned about the future, 3) people who want to drink safe water, eat uncontaminated food and be able to fish for un-poisoned fish, 4) simple folk who want to leave some unblemished wilderness for posterity and 5) others who may be suspicious of the promises of multinational corporations, is that we need to understand that we are dealing with powerful, sometimes criminal, economic forces that have enough tainted money to 1) hire cunning, well-paid, amoral lobbyists, 2) donate enormous amounts of money to mercenary, pro-industry politicians, 3) hire intimidating, pro-industry thugs to intimidate activists and threaten scientists at public protests and t4) spend millions on seductive and deceptive media propaganda.

Not only that, but we need to understand that industry’s well-dressed lobbyists and lawyers often have unfettered access to meetings with politicians and policy-makers (meetings that are often closed to the loyal opposition) and they frequently get interviewed  by journalists who may then rely on their glossy four-color corporate propaganda material for their stories.

Rio Tinto plc, exactly like all the other multinational corporations, owns or has substantial holdings in hundreds of mines and subsidiaries all over the world. All of them are points of potentially lethal pollution.

The largest (and only) Rio Tinto copper operation in the US is the Kennecott complex in Utah, the state where Swedish immigrant, miner and union organizer Joe Hill was framed for murder in 1914 and executed by firing squad the next year. Copper mine bosses hated union organizers like Hill, and they used all their considerable economic, political, judicial and police power for maximizing profits.

Of course, it is important to acknowledge that trans-national mining corporations have no loyalty to any nation or state; and, as with every corporate entity that qualifies for the diagnosis of sociopathic personality disorder, it should come as no surprise when they under-pay, over-work, threaten, fire and even kill their disobedient workers and union activists like Joe Hill.

I end with the classic union song about Joe Hill. (Listen to Joan Baez’s 1969 Woodstock rendition of this song at:

I Dreamed I saw Joe Hill Last Night

By Alfred Hayes 1938

I dreamed I saw Joe Hill last night
Alive as you or me
Says I, but Joe, you're ten years dead
I never died, says he
I never died, says he

The Copper Bosses killed you, Joe
They shot you, Joe, says I
Takes more than guns to kill a man
Says Joe, I didn't die
Says Joe, I didn't die

In Salt Lake, Joe, says I to him
Him standing by my bed
They framed you on a murder charge
Says Joe, But I ain't dead
Says Joe, But I ain't dead

And standing there as big as life
And smiling with his eyes
Joe says, What they forgot to kill
Went on to organize
Went on to organize

Joe Hill ain't dead, he says to me
Joe Hill ain't never died
Where working men are out on strike
Joe Hill is at their side
Joe Hill is at their side

From San Diego up to Maine
In every mine and mill
Where workers strike and organize
Says he, You'll find Joe Hill
Says he, You'll find Joe Hill

I dreamed I saw Joe Hill last night
Alive as you or me
Says I, but Joe, you're ten years dead
I never died, says he

I never died, says he