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Leach Pads

Understanding Leach Pads

The concept of leach pads is interesting and wide ranging. Leach pads are large, impermeable foundations which are used as the base for ore during heap leaching. The pads prevent the ore solution from escaping out of the circuit. However its purpose is worthless when viewed in isolation, instead of in its entirety as part of a civil engineering solution offered by these professional firms.

Leach pads are used together with other aspects in civil engineering projects, ranging from landfill applications to canal linings and the management of environment and hazardous waste. Engineering has been an important aspect of any developed nation, and what is known today as civil engineering dates back to nearly 6000 years ago. During this stage in history other important aspects became a priority such as transportation, which led to the development of the wheel and sailing boats. In today’s world, technology has improved so much that a civil engineering firm specializes on a number of different expert fields, including that of bulk water supply, water purification, canals and sewerage management. There are other applications and fields which also use the expertise of a civil engineer, and their influence and importance can be felt throughout many different industries.

Civil engineers are becoming more and more important in today’s society. Their expertise is required for building quality and sturdy transportation systems such as highways, rail lines, sea ports and airports. Civil engineering is concerned with determining the correct design for these structures, and looking after the construction process so that the permanence and durability of these structures are fully assured after the conclusion of the construction.

Dump leaching is an industrial process to extract precious metals and copper from ores. It is similar to heap leaching, but in this case the ore is taken directly from the mine and stacked on leach pads without being crushed. With gold and silver, the dump is irrigated with an adulterate cyanide solution which seeps into the ore to liquefy gold and silver. This solution, which contains the silver and gold, then exits the base of the dump and is collected and the precious metals extracted. The resultant barren of the solution is then recharged with additional cyanide, and returned to the dump. This method of leaching is normally fitting for low grade ores because it is extremely cost effective. Nevertheless it still operates with slow kinetics, and may take up about one to two years to extract only 50% of the desired mineral.

Gast is committed to seeing each civil engineering project through to the end. Utilizing the latest technology available, including mining and leach pads, there is no civil engineering project Gast will refuse. As a further testament to their clients, Gast subscribes to the ISO 9001 assurance quality control system. The ISO 9001 system administrates all aspects of the civil engineering operation, with specific emphasis on Design and Contract overview, the Quality of Materials and Workmanship, Inspection and Testing, Traceability and Document Control. Allow Gast to assist with all your civil engineering and leach pad requirements.