Medium-scale Mining

Medium-scale mining refers to mining that is larger than artisanal or small-scale mining but smaller than large-scale mining. Its exact definition may vary by country and also between different organizations within a country. Some criteria are based on the yearly man-hours employed in the mining operation and others on either the total mass ore extracted, the mass of metal (or non-metallic mineral) extracted or the dry-equivalent mass of ore concentrate produced.

Definitions

The Chilean mining guild Sociedad Nacional de Minería (SONAMI) defines medium-scale mining as those producing copper in the range of 1,500 to 50,000 metric tons per year. For the mining of other metals and non-metallic mining SONAMI's definition of medium-scale mining is based on equivalents on the tonnage that defines medium-scale copper mining. For Chile's National Geology and Mining Service medium-scale mining is that which employ between 1 million and 200 thousand man-hours per year, which is equivalent to a full-time workforce of between 80 and 400 persons. For Chilean state-owned company Empresa Nacional de Minería (ENAMI) medium-scale mining is different from the small scale mining in that it has a monthly produce of exceeding one of the following; 300 metric tons of dry copper concentrate, 150 metric tons of dry gold-silver concentrate, 100 metric tons of dry copper precipitate or else a total produce of 10,000 metric tons of mineral. The Chilean Copper Commission uses a definition offered by the Instituto de Ingenieros de Minas de Chile in 1990 which considers medium-scale mining as those mining companies producing between 3,000,000 and 100,000 metric tons of copper yearly (8,000 to 300 dayly). In Peru the law ''Ley General de Minería'' defines medium-scale mining as that which has a dayly produce of in the range from 350 to 5,000 metric tons ore concentrate or more processesed ore.

Medium-scale mining in Chile

In Chile medium-scale mining is concentrated near roads or other pre-existing infrastructure, and lie thus away from the high Andes where nearly all mines belong to the large-scale mining category. For mines with an annual produce of less than 10,000 metric tons a simplified mine closure procedure apply in Chile. ENAMI has in its role the purchase of ore from medium and small-scale mining which it does at stabilized prices to avoid volatility. There are multiple policies in Chile that tend to group media and small-scale mining together. Medium-scale mining in Chile tend to focus on copper and produced about 4.5% of the copper mined in the country from 2017 to 2021, with Chile being the world's largest producer of copper.Copper production in 2024 by USGS
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Medium-scale mining in Chile has a high rate of success in the environmental impact assessments with an approval rate of 92% from 2017 to 2022. Yet these approvals last each for a few years as projects submitted by medium-scale mining involve short time-frames. A 2017 study show that medium-scale mining in Chile is 23% less efficient in its use of water relative to large-scale mining, yet it has been suggested to be in favourable conditions to apply environmental techniques such as dry tailings relative to large-scale mining.

References

Bibliography

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*{{cite book, last1=Ulloa Urrutia, first1=Alfie, last2=Contreras Biekert, first2=José Luis, last3=Gana Aravena, first3=Joaquín, last4=Miranda Toledo , first4=Rodrigo, last5=Chauveau Gerber, first5=Paul, first6=Fernando, last6=Villalobos Valenzuela, last7=Farías Soto, first7=Javiera, title=Productividad en la Gran Minería del Cobre, chapter=, year=2017 , pages= , publisher=Comisión Nacional de Productividad, language=Spanish, isbn=978-956-7725-08-3

Mining