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Anglo Gold and its Colombian Quebradona project 

*This article was recently published in Colombia in action written by the Colombian Support Network. You can also read the original version here :…

by Al Gedicks Emeritus Professor of Environmental Sociology of the University of Wisconsin-La Crosse and Executive Secretary of the Wisconsin Resources Protection Council 

The multinational mining corporation Anglo Gold Ashanti has developed a plan for a large mine in Antioquia province of Colombia. An article with the most detailed public relations information on the project can be seen in a posted video by the company at First mine production is projected for the second half of 2025, preceded by a four-year construction period. The article describes the proposed copper-gold mine as a “megaproject.” The physical dimensions of the mine are indeed gigantic. I’ve converted the measurements from the metric system to the more familiar measures of feet and miles. The project will treat 6.2 million tons annually over a 23-year life. The project will produce 3 billion pounds of copper, 1.5 million ounces of gold and 2.1 million ounces of silver. Given the steady decline in the grades of ore, 20 tons of mine waste are generated to produce a single gold ring. Similar ratios apply to copper production. Elemental copper made up 0.74 percent of copper ores mined in 2005; by 2017 that had fallen to 0.59 percent. Overall, copper mines produced an additional 1.4 billion annual tons of extra waste in 2017 compared to 2005. About half of that can be attributed to ore decline, with the other half coming from increased production. https://…  

The mineral deposits are buried at a depth of over 1,300 feet. Excavating this deposit will create a crater approximately 1200 feet deep and a half-mile long. This will produce a large overburden pile that will have to be stored on site and monitored for possible toxic discharges. Such a large pit will also create a “cone of depression” around the pit that will drain the water from the surrounding area around the “hydrologic star” of the mountain. The waters around this “hydrologic star” include “nearly 18 rivers and streams” that “begin there and flow directly into the Frio River, the Cartama River and the Cauca River.” Digging a pit this deep is like taking the plug out of the bathtub. All the water will be drawn to the drain and require extensive dewatering. Such a large-scale dewatering operation would have a devastating impact upon the water supply that now supports an extensive agricultural sector. 

Hard rock or metallic mines (copper, gold, zinc, etc.) use water in every step of the mining process from separating waste from valuable minerals to controlling dust and storing large quantities of waste rock in tailings or waste impoundments. Anglo’s public relations video says that water diverted from the Cauca River will be less than 0.25 cubic meters per second, consuming less than 1 % of the flow of the river. The water will be used for mine construction, operation, closure and post-closure activities. Conflicts between mining companies and local communities over water in Latin America have escalated dramatically in recent years, affecting the reputation of the mining industry and its social license to operate controversial mining projects. 

Water quantity is only part of the problem. The copper-gold minerals are embedded in a sulfide orebody. When the rock is blasted out of the mountain, crushed sulfide rocks and particles interact with oxygen and water and create sulfuric acid. Sulfuric acid dissolves and mobilizes toxic heavy metals producing a substance known as Acid Mine Drainage (AMD) which leaches indefinitely along the pit walls, the ore and mine waste stockpiles, the tailings dam and into aquifers, streams and rivers. The leaching may continue for decades after mining has ceased. AMD is a perpetual pollution machine. 

According to Anglo’s promotional video, water treatment plants and sediment ponds will be built to treat domestic and non-domestic effluents generated by the project insuring that all AMD and tailings drainage are treated correctly with active or passive treatments, guaranteeing compliance with environmental legislation and air quality when they are returned to the Cauca River. The video also states that the tailings from the milling plant will be separated into inert material and pyrite, the principal sulfide mineral capable of generating AMD. Both the inert tailings and pyrite will be filtered to a moisture that will guarantee the stability of the tailings dam. Both will be transported through the project’s internal roads by 30-40 ton trucks from the stockpile to the tailings and pyrite impoundments. The pyrite deposit will be underlain by a geomembrane and covered with filtered tailings approximately 35 feet high to limit the oxygen and water into the tailings dam and the generation of AMD. 

A literature review of AMD for the U.S. Fish and Wildlife Service had a sobering conclusion regarding industry attempts to control AMD: “The mining industry has spent large amounts of money to prevent, mitigate, control and otherwise stop the release of AMD using the best available technologies, yet AMD remains as one of the greatest environmental liabilities associated with mining, especially in pristine environments with economically and ecologically valuable natural resources. Problematic to the long-term operation of large-scale metal mines is recognition that no hard rock surface mines exist today that can demonstrate that AMD can be stopped once it occurs on a large scale. Evidence from literature and field observations suggests that permitting large scale surface mining in sulfide-hosted rock with the expectation that no degradation of surface water will result due to acid generation imparts a substantial and unquantifiable risk to water quality and fisheries.” https://www assets/uploads/20 l 8/ 12/55-S .R.- Jenning-et-al .-2008.Acid-Mine- Drainage-and-Effects-on-Fish- Health-and-Ecology-A-Review.pdf 


Anglo Gold’s Militarization of the Ouebradona Project 

Anglo’s promotional video prides the company on its “shared values with the communities” and support for sustainable development. However, the company’s reliance upon the police and the military to impose the project on the community tell a different story. 

The El Espectador article mentions the Mayor ofTamesis’s “historic and profound rejection of mining exploitation in the territory” and the public demonstrations in defense of water and biodiversity. In November 2018 the neighboring municipality of Jerico banned all mining in the coffee-growing community. Anglo Gold responded by asking the police, the military and even the “feared riot police unit ESMAD to make sure they could ignore the local ban.” According to Colombia Reports, the locals found out about the riot police beforehand, “and using social media, mobilized the town to make sure that Anglo Gold Ashanti respect their decision not to convert one of the mountains that characterize the region into an open-pit goldmine” anglogold-ashanti-believed-it-was-above-colombias-lawuntil-farmers-stepped-in/ 

According to a recent survey by Ernst & Young Mining &Metals, more than half of global mining companies believe that license to operate, or acceptance and permission from communities and society, is the biggest risk to their business -jumping seven places up the list from 2018.”Mining companies are now recognizing this is a strategic concern,” says Jimena Blanco, head of Latin America research at Verisk Maplecroft, “and an operational one too; it’s not just about having some corporate responsibility programmes and investing in the local community; there is a recognition this affects the bottom line.”… 

The proposed underground mine would produce nearly 119 million tons of toxic wastes that would be stored in a tailings dam over 700 feet tall and covering an area of about 200 football fields. The tailings are the waste material left over from the crushing, grinding and chemical processing of mineral ores. The chemicals used to separate the gold from the waste rock include cyanide. Anglo Gold says they do not plan to use cyanide in the milling process. This would be highly unusual because cyanide is the cheapest and most widely used process to extract gold. The tailings often contain residual minerals - including lead, mercury and arsenic that can be toxic if released to the environment. However, unlike water-retaining dams made of concrete and steel, tailings dams are held back by the tailings themselves, which have the consistency of talcum powder or fine sand. 

Contrary to the claims of safety by the mining industry, tailings dams are failing with increasing frequency and severity. The greater the volume of tailings and the higher the tailings dam, the greater the chance of structural failure. Tailings dams are most often constructed in sequential “lifts” or “raises” over several years, making quality control more challenging than for water supply dams that are constructed all at once. According to Dr. David Chambers, an internationally recognized tailings dam expert, “the failure rate of tailings dams has remained at roughly one failure every eight months, or about three failures every two years. Over a 10,000 year lifespan (a figure often used for how long these structures will need to maintain their integrity) this implies a significant and disproportionate chance of failure for a tailings dam.”   

When they fail, they can destroy entire communities and livelihoods. The 2019 Brazilian tailings dam disaster killed 270 people and contaminated 75 miles of the Paraopeba River, where mud, debris and dead fish devastated the Pataxo Indigenous people who depend upon the river for drinking, fishing and irrigation. There have been 43 tailings dam failures in the past 20 years. 

Anglo Gold says they will construct a “dry tailings deposit.” Tailings are generally placed behind the dam in water-slurry from the mill, and can remain saturated for long periods. Saturated, unconsolidated material is susceptible to becoming liquefied due to heavy blasting during mining excavation or seismic activity. It’s not clear whether Anglo’s reference to a “dry tailings deposit” is the same as the “dry stack” method of tailings dam construction, which is a safer method of tailings storage, but also much more expensive than wet tailings storage. Wet tailings pose a greater danger of “liquefaction” where heavy rains can increase the weight of the material inside the dam and liquefy relatively dry mine waste that can then spill out, overwhelming and drowning people in its path. The “dry stack” method is not the industry standard due to its greater cost. It is also far from clear that filtering the pyrite tailings to “a moisture” to guarantee the stability of the tailings dam is the same thing as a “dry tailings deposit.” Anglo Gold’s plan to use the tailings to pave roads in the area is an environmentally reckless proposal that will only increase geographical reach of all the problems associated with AMD.…

The upstream dam construction design is the most common type of tailings dam because it is the cheapest. The construction material does not have to be imported because it is composed of the tailings themselves. The other types of dam construction are the downstream and centerline dam designs, that are safer and much more expensive to construct. Given the large volume of tailings that will be created with this project and the extreme height and area occupied by the dam, the most likely design would be the upstream design. This design has the highest worldwide rate of catastrophic failure and has been banned in Brazil, Chile, Ecuador and Peru. 

Earthworks, a national environmental organization in Washington, DC has recently called for a ban on tailings dams using the upstream construction method, and for the closure of existing upstream dams. In June 2020, an international group of 142 scientists, community groups and NGOs from 24 countries called for the banning of upstream dams in favor of centerline and downstream dams, which are much less vulnerable to all mechanisms of dam failure. “Additionally, dams must not be built in close proximity to communities or above mining infrastructure where workers are likely to be present.” https://www. safety-first-new-reportoutlines-guidelines-to-end-mine-waste-disasters/ 


Quebradona will be a third of the value of Anglo Gold 

The Quebradona project is a high-value and high-risk project for the company. Anglo Gold just sold the last of its South African mines, the giant Mponeng, west of Johannesburg. The company just had an underground accident in May that called into question its mine engineering competence. 

The new CEO of Anglo Gold is Alberto Calderon, a Colombian who is not a mining engineer. He has never managed gold assets. His prior mining experience included managing the controversial El Cerrejon coal-mining project among the Wayuu Indigenous people of La Guajira. The environmental and health impacts of the Cerrejon mine are well documented and have been the subject of several court rulings in recent years. 


Recommended Action 

This project is a major gamble for the company. This megaproject poses major environmental and economic risks to the community that have generated significant political opposition over several years. It should be clear to investors that this project has no social license and will be subject to ongoing resistance by communities that will protect their rights to clean water, to the forests and to their agricultural livelihoods. 

The international visibility of the Andean bear has already been recognized by the International Nature Conservation Union. Other international wildlife organizations like World Wildlife Fund (WWF) are potential allies. 

A letter addressed to Alberto Calderon and his board of directors highlighting some of the environmental, political and reputational risks of this project may have some impact on whether this project goes ahead. The letter should be co-signed by as many environmental, wildlife and human rights groups as possible. Mr. Calderon and his board need to understand that this project is being closely watched

Al Gedicks