Waste Rock and Heap Leach Cover System Performance Evaluation
Location
Peru
Client
Minera Barrick Misquichilca Pierina
Project Description
GSA designed and monitored a multilayered store and release cover system to reduce net percolation and oxygen ingress into closed waste facilities in an area with extreme seasonal precipitation (>1000 mm in six months). We performed both in-situ and laboratory hydraulic characterization of waste rock, heap leach and potential cover materials to develop unsaturated flow property estimates for cover system modeling. Experimental test plots to assess net infiltration, surface water runoff and erosion were constructed. Instrumentation consisted of multiple cover performance monitoring systems and surface water flow monitoring to perform a complete water balance. Monitoring was performed for 3.5 years with a final field investigation to determine rooting and how clay liner permeability changed over time.
Project Highlights
- Design of multi-layer cover system test panels
- Design and implementation of cover performance monitoring and surface water runoff monitoring systems
- In-situ and laboratory hydraulic characterization of cover and waste rock material
- Cover system performance monitoring