7 Sep, 2018, 15:30 - 15:50

Silverio Prota, General Manager, ANDDES S.A.

Curriculum Vitae
Silverio has over 24 years of experience in the engineering and environmental consulting fields for the Energy and mining industries. His fields of expertise include: Electric Leak Location, Due Diligence, Site Assessment and Remediation of contaminated sites, RBCA, Construction Quality Assurance (CQA) and Environmental Studies. Silverio has surveyed over 900.000 m2, detecting leaks from 0.5 mm, applying innovative ASTM and non ASTM technologies. In addition, Silverio has characterized and/or remediated over 100 sites contaminated with petroleum products and heavy metals. Regarding site assessment and characterization, Silverio has participated in more than 100 projects involving petroleum and heavy metals remediation. His professional career has been developed in the United States, Argentina, Perú, Mexico, Panama, Brazil and Uruguay

Summary

Innovative technologies may allow for significant increase in precious metals production at leach pads. This presentation will cover two of them. The first one is about Dipole Electric Leak Location (ELL), to be conducted by ASTM D7007 right after overliner installation, when more than 70% of damage to geomembrane liner occurs. . The dipole method experience detailed comes from high altitude heap leach pads in the Andes, where the technology successfully detected damage locations of various sizes, several of them extremely significant. From both a financial and technological point of view, incorporating the dipole ELL method is a far more effective CQA tool than what is currently used in preventing future environmental impacts, potential legal claims and certain loss of revenue through leaks that could have been easily detected by ELL during the heap leach pad construction phase. The second technology for Leach Pad optimization is called “Secondary Recovery”. Secondary recovery refers to an injection method applied towards the end of the heap’s life cycle for drawing down the remaining metal inventory. Through years of heap investigations using 3D geophysical mapping, it has been discovered that low permeability ore is a main cause for low gold recovery. Low permeability can compound the problem in other ways, for example creating shallow perched water tables that intercept cyanide that would have otherwise percolated through the ore. The secondary recovery method targets these low permeability areas with fresh cyanide solution, thus focusing the delivery of cyanide to areas of greatest need. The proven methodology recovers ounces that would have otherwise been lost