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» Yanacocha Mine, Peru
 

The expanding Yanacocha Mine dominates the land change seen in this series of images. Operated by the Newmont Mining Corporation in Greenwood Village, Colorado, the Yanacocha Mine is the second largest gold mine in the world, and the largest in Latin America. Consisting of seven distinct deposits, the open pits cover over 30,000 hectares of land.

The mine is located about 45 kilometers from Cajamarca in northern Peru on top of Yanacocha Mountain at an altitude of 4,700 meters, nestled in the Andes Mountains.

Mining operations at Yanacocha have been continuously expanding since 1993. Production peaked in 2005 when the mine produced 3.33 million ounces of gold. In 2014, just over 1 million ounces of gold came out of the mine. As of December 31, 2014, reserves are estimated to be 155 metric tons of gold.

In these false-color Landsat images, the expansion of the open pit mining is shown in varying shades of pink. Green is vegetation, and agricultural areas near the city of Cajamarca (visible as bright pink and purple shades) appear as bright green in the bottom center of the images.

Map of the featured area.

Just west of the mining area, a dark green patch of land emerges in the time series of images. This is a cooperative farm called Granja Porcón. The 12,000 hectares of land in the cooperative were originally grassy plains.

The dark green area on the images indicates the effects of an afforestation project. Granja Porcón includes a nursery that produces over a million seedlings per year, and the forest plantations provide wood as a source of income for the local population. Pine species are planted in this location because of their resistance to cold at high elevation.

Tourists can visit and work alongside the residents of the cooperative in day-to-day tasks, such as milking cows or working in the fields.

Gold is found in the Yanacocha Mine in microscopic bits. One hundred tons of earth need to be removed for every ounce of gold extracted. The large volumes of material are dumped onto a lined leach pad, and cyanide solution is sprayed over it. The cyanide binds with the gold and causes a solution enriched with gold to settle at the bottom. The gold can then be extracted from that solution.

Environmental risks of large-scale open pit mining are complex and uncertain. One impact is the potential risk of cyanide contamination on soil and water. Satellite data along with ground studies can help show the land change effects of mining operations, such as groundwater quality and watershed changes.

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