COLOMBIA MERCURY INVENTORY 2011

Mercury was mined, retorted, and used for small-scale gold production and cinnabar was used as a part of funeral rites in the ancient Andes. La Esperanza (Dept. Caldas), Colombia's most well-known mercury mine, closed in the 1960s. However, mercury is now acknowledged as a global contaminant by the US State Department, the United Nations Environmental Program, the US Environmental Protection Agency, and other agencies. 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 and has attempted to reduce the use of mercury for small scale gold mining from 140 t/y to 70 t/y. The United Nations Industrial Development Organization planned to invest $1.7 million dollars to 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 Quibdó, western Colombia, alluvial gold 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 Colombian university scientists in Medellín has resulted in reduction in the use of mercury at intermediate-sized gold mines, in Nariño and Antioquia, respectively. In 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, none of the 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 >$1600 per ounce, continue to drive the use of mercury, despite the parallel increase in mercury prices, to >$3000 per 34.5 kg flask.