Kori Kollo

The case of the Kori Kollo gold mine is an emblematic case where a transnational mining company takes valuable precious metals and leaves a severely contaminated area for the local people. Catapa is following this case from the very beginning in collaboration with local partners CEPA and Coridup.


The Kori Kollo gold- and silver mine is situated at about 3,710 meters above sea level in the Bolivian plateau (altiplano). The mine is part of the department Oruro and is located over 42 kilometres northwest of the city Oruro and over 160 kilometres southeast of the capital La Paz. Oruro has a semi-arid climate, which means that 9 months of drought alternate with a rainy season of 3 months. Over the period of 12 months, there is a rainfall deficit, as there is more water evaporating than raining down. As a result, fresh water is relatively scarce.

The mine is situated at the Desaguadero river, which is mainly supplied by Lake Titicaca and flows into the lakes Poopó and Uru Uru. At the height of Kori Kollo, the river is divided in two: the left flows to the Uru Uru lake, from where the water overflows into Lake Poopó; the right branch flows directly into Lake Poopó. Both lakes are covered by the international Ramsar convention, which means they are recognized as wetlands of international interest.


The Kori Kollo mine was actively being exploited from 1980 to 2010 by the company Empresa Minera Inti Raymi S.A. (EMIRSA). This company had several (majority-) shareholders over time. Initially, the distribution among shareholders was 50% Bolivian (with Zeland Mines of Bolivia) and 50% North-American (Westworld Resources, US). From 1988 onwards, Battle Mountain Gold started buying themselves in and by 1995, they possessed about 88% of the shares of EMIRSA. In 2001, Battle Mountain Gold was taken over by Newmont Mining Corporation. In 2009, the latter sold all his shares to the Bolivian Compania Procesadora de Minerales SA, with a clause to receive an annual lump sum from EMIRSA in the coming years.

Around 1980, the first exploration and the preparations for the later exploitation started. From 1984 onwards, ore (oxides, and later sulphides) was actively being extracted and locally processed by grinding and piling the ore on leaching platforms which are being sprayed with cyanide. The cyanide extracts the different precious metals (such as gold and silver) from the ore. This solution is collected and then processed to finally only leave the precious metals.

Between 1985 and 2010, a total of 122’633kg gold and 382’501kg silver was produced. The mine also generated 144 million tons of waste rock, used at least 53 million m3 water. Kori Kollo was originally the name of the mountain which has totally been excavated during the mining process, to a depth of approximately 240 meters deep. With the closing of the mine, this well was filled with water from the Desaguadero river.


The Kori Kollo has several consequences for its surroundings, mainly downstream. Apart from nuisance by noise and dust, the transports of cyanide and the dumping of contaminated waste rock, the biggest problems are situated around the water, in different ways.

  1. Since the mine needs large amounts of fresh water for its extraction- and production processes, the current through the right branch of the Desaguadero river has been artificially increased by excavation works. As a result, the Uru Uru lake (fed by the left branch) receives less water, making it significantly smaller. This is being denied by EMIRSA, but has been affirmed with historical satellite images used by researchers from the local university (UTO). A big part of the water that is drained from the river’s right branch gets lost in the production process.
  2. When digging the mining well, there is a continuous influx of ground water in the well. To keep the well dry, the (salt) ground water is being pumped and stored in big evaporation lakes. Because of the composition of the subsoil, this water also contains high concentrations of heavy metals. The water evaporates, after which a salt crust (with heavy metals) stays behind. At heavy precipitation during the rainy season, these evaporation lakes sometimes receive huge amounts of water because of which the embankments risk to break down. The freed water then ends up in the river, which takes the salt and heavy metals to Lake Poopó. Along the way, the river can overflow its banks and leave polluted silt.
  3. The pumping of water to keep the mine dry also has an influence on the balance of the ground water. Several communities downstream of the mine complain about dried out and/or silted groundwater wells.
  4. The inadequate storage of the polluted waste rock leads to the release of heavy metals which infiltrate the soil en thus contaminate the ground water.


De fishing communities from the Uru Uru Lake claim that they could already feel the consequences of the Kori Kollo mine in de 80s. Also other agriculture communities located downstream of the mine started to feel more and more hindrance: silted groundwater, births of deformed animals, health issues both for people and animals, silted soils, a lack of water. EMIRSA only received an environmental license for the mine around 1997, since before these licenses were not required because there simply weren’t any environmental laws that could conceive operations of this kind.

The complaints became more numerous and louder and in 2000 about 80 communities united in the organization Coridup (Coordinadora en defensa de la cuenca del Rio Desaguadero, los Lagos Uru Uru y Poopó). A total of almost 1,000 official complaints were filed at the ministry, signed by more than 10,000 people. In 2003 a hunger strike led to an investigation commissioned by the government. It would take 6 more years until in 2009 the ministry commissioned an official environmental audit by the Bolivian Auditor (PCA Ingenieros Consultores SA) with money from EMIRSA (1.25 million dollar). The government would guarantee the independent control. The  Centro de Ecologia y Pueblos Andinos (CEPA), a local NGO from Oruro, supported Coridup in their battle for socio-ecological justice by offering technical-scientific, juridical and organizational support.


The start of the audit went arduously and in the end the audit was considerably delayed. The audit was executed in 3 phases. When the midterm report came out, everyone had the chance to go through the text and formulate comments for the state representative within 15 working days. Catapa and Cepa together coordinated a team of Belgian and Bolivian volunteers who revised the voluminous documents (700-1200 pages).  The fact that national and international academics followed up on the audit, made the government and the audit agency feel controlled and adjust the content. Nevertheless the quality of the research was deplorable. For some parts, outdated research methods were used, the expertise of researchers was limited and the research was not enough integrated. However, it was concluded that contamination of ground water, soil and surface water was assessed, but the legal liability of the mining company remained vague.

With a much more limited budget, Catapa and Cepa commissioned the local university  Universidad Tecnica de Oruro (UTO) to execute an alternative study on the impact of the Kori Kollo gold mine on the environment. The financial expenses were divided among the different institutions. The conclusion of this study was much more severe. The diversion of the river branch, the mobilization of heavy metals in the  ground water, the silting of the area, the serious impact of on the local fauna and flora were scientifically motivated.


As the official audit has ended, the responsible minister considers the case as closed. Despite persistent protest of Coridup, there is little movement. Coridup now denounced the situation with the Human Rights Council of the United Nations. The special representative of the UN Commission already recognized in 2008 en 2009 that the rights of the indigenous people were being violated if nothing happened to tackle the pollution. (to be continued, hopefully…)