Colombia Mercury Inventory 2011

Abstract

In the ancient Andes, mercury was mined, retorted, and used for small-scale gold production and cinnabar was used as a part of funeral rites. Colombia's most well-known mercury mine, Mina La Esperanza (Dept. Caldas), closed in the 1960s and now, mercury is acknowledged as a global contaminant by the US Environmental Protection Agency, the US State Department, the United Nations Environmental Program, and many other organizations. Colombia is considered to be one of the top three users of mercury in the world. The government of Colombia is concerned about environmental contamination from mercury releases and has attempted to reduce the use of mercury for small-scale gold mining from140 t/yr to70 t/yr. The United Nations Industrial Development Organization (UNIDO) planned to invest $US1.7 million dollars to help reduce the use of mercury in Colombia. In 2011, Colombia imported mercury from Mexico (23 t) and Spain (21 t) and the mercury was used for small-scale gold mining, chlor-alkali production, and neon lighting. In Remedios, north-central Colombia, and Chocó, western Colombia, alluvial gold (gold-silver-platinum) is being produced by mercury as well as non-mercury or "green-gold" methods. Many of the gold shops where the gold-mercury amalgam is burned have water traps to capture the mercury that is volatilized when the amalgam is burned. In Remedios, simple ball-mills, or entables, also use mercury to amalgamate the fine-grained alluvial gold before burning. Collaboration with Japanese researchers and the efforts of Universidad Nacional de Colombia scientists in Medellín has resulted in reduction in the use of mercury at intermediate-sized gold mines in Depts. Nariño and Antioquia, respectively. In Dept. Chocó, western Colombia, the use of mercury with dredges and sluices, which also cause increased sediment load in the rivers, has decreased. There is one mercury-cell chlor-alkali plant in Colombia and mercury is also imported in fluorescent and CFLs, dental amalgam capsules, thermometers, batteries, light-up kid's shoes and toys; however, no mercury is recycled. Some mercury-containing material may be encapsulated and then placed in landfills. Gold from the small-scale mines has been used to fund guerilla and paramilitary activities. Increased gold prices, to $US1,600 per troy ounce, continue to drive the use of mercury despite the increased mercury prices, to $US3,000 per 34.5 kg flask. Key words: mercury, gold, green gold, environment, retorting, amalgamation

En Colombia, se encuentran muchos afloramientos de cinabrio, la mena de mercurio. En tiempos prehispánicos, el mercurio fue usado para la minería de oro a pequeña escala y el cinabrio fue usado en rituales funerales. La mina principal de mercurio en Colombia, La (Nueva) Esperanza, Departamento Caldas, fue cerrada en los 1960s.Pero hoy día, agencias internacionales como el U.S. Environmental Protection Agency, el U.S. State Department, y el United Nations dicen que el mercurio es un elemento muy tóxico al medio ambiente y al ser humano. Colombia es uno de los tres lideres mundiales en el uso del mercurio. A causa de los efectos del mercurio en el medio ambiente y en el ser humano, el gobierno Colombiano quiere reducir el uso de mercurio, de 140 t/a hasta 70 t/a. UNIDO (United Nations Industrial Development Organization) quiere invertir $US1.7 millones para reducir el uso de mercurio en Colombia.En 2011, Colombia importó mercurio de México (23 t) y España (21 t) para uso en minería a pequeña escala, producción de cloro, y lámparas con neón. En Remedios, Departamento de Antioquia, en el norte de Colombia y en el Departamento de Chocó en el oriente, se usa mercurio para agarrar oro (Au-Ag-Pt) y tambien se usan métodos sin mercurio para producir “oro verde.” Muchos de los talleres de oro tienen trampas, con agua, para retener los vapores de mercurio después de quemar (refogar) la amalgama (Hg-Au). Tambien, en Remedios, Departamento Antioquia, se usan entables, con mercurio para amalgamar el oro fino de los aluviones. Estudios realizados por cientificos japoneses e investigaciónes de los cientificos de la Universidad Nacional (Laboratorio CIMEX) en Medellín han dado como la disminución del uso del mercurio en minas de oro a mediana escala en los Departamentos de Nariño y Antioquia. En el Departamento Chocó, el uso de mercurio con las dragas, que tambien dejan muchos sedimentos de grano fino en los rios, se ha reducido. En Colombia, hay solamente una planta de cloro que tambien usa y recicla mercurio. Colombia no tiene plantas de reciclaje para productos como lámparas fluorescentes, amalgama dental, termómetros, juguetes, y zapatos de niños. Por consiguiente, la mayoria de los residuos con mercurio se disponen en la basura o quizas en los rellenos sanitarios. Tambien, hay evidencia de la explotación de oro en minería a pequeña escala para financiar las actividades de los grupos al margen de la ley. A causa del incremento en los precios de oro, $US1500 por onza troya en 2011, se incrementó el precio de mercurio llegando a un valor de $US3000 por frasco (34.5 kg). AbstractColombia has many occurrences of cinnabar, the ore of mercury, and in the ancient Andes, mercury was mined, retorted from cinnabar, and used for small-scale gold mining. However, La (Nueva) Esperanza, Dept. Caldas, Colombia’s most well-known mercury mine, closed in the 1960s. Mercury is acknowledged as a global contaminant by the U.S. Environmental Protection Agency, the U.S. State Department, the United Nations Environmental Program, and many other world organizations and Colombia is one of the top three users of mercury in the world. The Government of Colombia is concerned about environmental contamination from mercury releases and has attempted to reduce the use of mercury for small-scale gold mining from140 t/yr to70 t/yr. The United Nations Industrial Development Organization (UNIDO) planned to invest $US1.7 million dollars to help reduce the use of mercury in Colombia. In 2011, Colombia imported mercury from Mexico (23 t) and Spain (21 t) and the mercury was used for small-scale gold mining, chlor-alkali production, and neon lighting. In Remedios, Dept. Antioquia, in north- central Colombia, and Dept. Chocó, western Colombia, alluvial gold (Au-Ag-Pt) is produced by mercury as well as non-mercury “green gold” methods. Many of the gold shops where the gold-mercury amalgam is burned have water traps to capture the mercury that is volatilized when the amalgam is burned. In Remedios, simple ball-mills, or entables, also use mercury to amalgamate the fine-grained alluvial gold before burning. Collaboration with Japanese researchers and the efforts of Universidad Nacional de Colombia (CIMEX) scientists in Medellín has resulted in reduction in the use of mercury at intermediate-sized gold mines in Depts. Nariño and Antioquia. In Dept. Chocó, the use of mercury with dredges and sluices, which also cause increased sediment load in the rivers, has decreased. There is one mercury-cell chlor-alkali plant in Colombia and some of the mercury is recycled in-plant. Mercury imported in fluorescent and CFLs, dental amalgam capsules, thermometers, batteries, light-up kid’s shoes and toys commonly ends up in the wastestream and is not recycled. Some mercury-containing material may be encapsulated and then placed in landfills. Increased gold prices, to $US1,500 per troy ounce in 2011, continue to drive the use of mercury and the rise in mercury prices to $US3,000 per 34.5 kg flask.