The Geosynthetic Institute (GSI) will sponsor a webinar, “Geosynthetic Applications Used in Heap Leach Mining,”on August 11, from 11:30 a.m. to 1 p.m. EDT. Geosynthetic Materials Association (GMA) member companies and their employees receive discounted rates on all GSI webinar and short course registrations.
The chemical extraction of precious metals from low-grade ore and tailings has been ongoing since the 1950s. Gold, silver and copper are the general targets, wherein heaps of the ore are leached with cyanide or sulfuric acid, which gravitationally flows to the base with its dissolved metals and is then collected by a drainage system. Of course, a geomembrane must be beneath the heap, or the pregnant leach solution will escape. (Incidentally, it is estimated that almost 40% of all geomembranes are being used for this application.) The metal is then recovered from the leachate in an on-site processing plant. The barren liquid is revitalized and sent to the top of the heap for recirculation until the process is no longer economic. In this webinar, the various heap configurations and operations will be described.
The major design issues of geomembrane selection, leach drainage pads, slope and heap stability, liquefaction potential and pond liner decisions are described in as much detail as time permits.
Reflections on the technology as well as summary, conclusions and recommendations are offered.
Webinar participants will learn the concept, technique and idiosyncrasies of heap leach mining as is currently practiced worldwide. Critical in the technique’s success is the use of geosynthetics, including geomembranes, geonets, geotextiles, geosynthetic clay liners and geopipes. Five critical design issues will be emphasized. Among them are heap and slope stability (there are many stability failures) issues and procedures. Participants will learn about the economics of these massive operations vis-à-vis the environmental concerns that must be properly addressed.
- Understanding the concept and select details of heap leach mining
- Appreciation of the enormous scale of operations and various heap configurations
- Learn about the application of the leaching chemicals
- Learn about geomembrane selection
- Learn about various leachate collection schemes
- Learn about stability issues and some failures that have occurred
- Learn of the importance of high liquid heads and the possibility of liquefaction
- Learn about pond liner design
This webinar is intended for heap leach operations owners and operators; general civil and mining consulting engineers; geosynthetic manufacturers and distributors; testing organizations servicing these organizations; heavy construction contractors; federal and state regulatory agencies, academic and research groups; and others desiring technical information on this important aspect of precious metals recovery.
George R. Koerner, Ph.D., P.E., and CQQ, is the director of the Geosynthetic Institute. He is in charge of laboratory accreditation, field certification and continuing education at the institute. He also manages several research projects and has published more than 350 technical papers in his 35-year association with polymers used in below-ground construction. Koerner’s Ph.D. is from Drexel University in geotechnical engineering. He is a registered professional engineer and a certified quality auditor. Koerner has received many awards over the years. The most notable being IFAI’s Environmental Technologies Award of Excellence 1995, ASCE’s DVGI Geotechnical Engineer of the year in 2004, the title of ASTM Fellow in 2013 and GMA’s first Robert M. Koerner Lecture and Award in 2017.
Webinars cost $200.00 for GSI and GMA members, and $250.00 for nonmembers. Successful completion of a multiple-choice test after the webinar carries 1.5 professional development hours (PDH). For more information or to register, visit http://www.geosynthetic-institute.org/webinar.htm.