GEOAMERICAS 2016 10 – 13 APRIL 2016 MIAMI, FLORIDA

Advances in Geosynthetics for Heap Leaching

Course Outline

Updated 8 September 2015

Presenters: Mark E. Smith, RRD International Corp, USA Denys Parra, Anddes Asociados S.A.C., Peru Abigail Gilson-Beck, TRI/Environmental, USA

1. Welcome, introduction, opening remarks, Mark E. Smith

2. Geotechnical behavior, Denys Parra a. Soil-geomembrane interface characterization b. Non-linear shear strength envelope c. Interface performance with high loads d. 3-D stability, state of the art e. Comparison of 2-D & 3-D modeling f. Stability analysis: static & pseudo-static g. Seismic-induced deformation

i. Makdisi & Seed; Bray & Travasarou; Houston & Padilla ii. Finite element

h. Special pad & heap features i. Steep slopes

ii. GCLs iii. Valley fill heaps iv. Raincoats

3. Special considerations, Mark E. Smith

a. Bioleaching & Nickel i. Long leach cycles

ii. Strong acids (Ni) iii. High operating temperatures

b. Dynamic heaps c. Cold weather leaching d. Evaporative covers e. Drainage products to reduce overliner gravel f. Leach pad cost benchmarking

4. Performance monitoring of heaps, Denys Parra

a. Geotechnical instrumentation b. Aged ore testing c. Issues during operation

i. Design versus as-built ii. Interface strength overestimation

iii. Geosynthetics quality variability

5. Quality of installed facilities, Abigail Gilson-Beck a. ELL survey methods

i. Water-based bare geomembrane methods (ASTM D7703, D7002) ii. Arc and spark testing methods (ASTM D7953, D7240)

iii. Soil-covered dipole method (ASTM D7007) iv. Water-covered dipole method (ASTM D7007)

b. Designing mine facilities for ELL surveys i. Heap leach pads

ii. Ponds c. Design for zero (or very low) leakage

i. Materials and methods ii. Construction quality control

d. Cost/benefit analysis – dipole survey on heap leach pad case study

6. Risk management and project de-risking, Mark E. Smith a. Introduction to risk analysis b. Avoiding the silo effect c. Drained shell concept d. Coupling geomechanics, hydrogeology and geochemistry

ABOUT THE INSTRUCTORS Mark E. Smith, M.Sc., P.E., D.GE is Principal of RRD International Corp. Mark is a geotechnical engineer specializing in heap leach design, operation and closure. He has worked in heap leaching for 35 years, during which time he founded Vector Engineering. He currently serve on the directing boards of Brazilian Nickel and Piteau Associates as well as advised the University of Nevada – Reno’s College of Engineering. He consults internationally on a wide range of heap leaching issues and is currently engaged on projects in the Yukon, Peru, Brazil and Armenia, with many mining clients of Tier 1 and 2 levels. Denys Parra, M.Sc., P.E. is the General Manager of Anddes Asociados S.A.C. and Associate Professor of Geotechnical Engineering, National University of Engineering (Lima). He served as an engineering manager at Vector Peru for 13 years prior to founding Anddes Asociados, a Peruvian consulting company. During his 24 years of experience, he has performed research and consulting in and presented internationally on geotechnical and civil engineering for projects related to heap leach pads, tailings dams, waste rock dumps, geosynthetics, other mining facilities, foundation analysis, slope stability, soil liquefaction, 3-D stability analysis, earthquake-induced deformation analysis, and other geotechnical issues.

Abigail Gilson-Beck, M.Sc., P.E. is Senior Engineer for TRI/Environmental, Inc. She directs the company’s global electrical leak location services. With 15+ years of diverse civil engineering experience, Beck has performed and overseen 9 million sq. m of soil-covered, water-covered, and exposed geomembrane electrical leak location surveys. Her contributions to the field of electrical leak location include numerous published technical papers, educational seminars, presentations around the world, and chairing the ASTM committee for the recent revisions and additions to the ASTM Standard Guide and Practices.

Photo by Mark Smith