Metallurgical Monitoring – Enhanced Metal Recovery

Field reconnaissance metallurgical monitoring with mobile geochemical laboratory to reduce metal inventory in heaps and increase secondary metal recovery.

Field reconnaissance metallurgical monitoring with mobile geochemical laboratory to reduce metal inventory in heaHGI’s metallurgical monitoring service utilizes a mobile geochemical laboratory trailer, the Mobile Solutions Lab, is a well-equipped, field-ready, and climate controlled space that can be deployed onsite for performing both in-situ field reconnaissance of enhanced recovery projects and ex-situ detailed laboratory tests of ore or PLS samples. Field reconnaissance data, which have proven to be invaluable for understanding geomechanical and hydraulic performance parameters from enhanced metal recovery (i.e., direct injection) projects, include pressure, flow, and temperature monitoring with real-time presentation capabilities. Ex-situ monitoring includes acquiring geochemical data of soil and solution using state of the art bench top meters, colorimetric testing, titration methods, and other laboratory equipment for assessing internal conditions of heaps without the cost of a full laboratory analysis. When these are acquired with geophysical characterization methods, they can be invaluable for assessing the broad-scale state of heaps.


HGI’s metallurgical monitoring capabilities helps to provide geochemical context to leaching projects. We have the capabilities to measure key variables on the spot or have a chain of custody sample sent to an analytical laboratory.



HGI’s monitoring capabilities on heap leach pads to help optimize secondary metal recovery. Example of HGI’s monitoring and enhanced metal recovery tools.
In-Situ Monitoring

What is happening inside your pile when you inject as part of a secondary recovery project or stabilization process? Knowing the flow regime and lasting impact from a highly pressurized solution or slurry is important for maximizing efficiency.
In addition to the geophysical monitoring, HGI offers a suite of tools aimed at hydraulic monitoring of pressure, flow, and temperature inside your rock pile. These tools can tell a lot about your process and the geomechanical changes that may be occurring. To optimize your process, are you interested in:


• Permanent enhancement of hydraulic conductivity
• Rinsing without lasting geomechanical changes
• Pore dilation for effective solution coverage
• Pore filling and clogging to reduce flow


The in-situ data tell much about what is happening underground and knowing how to interpret it is a specialty offered by HGI. An example is shown below, which presents the pressure and flow data response of an injection meant to enhance hydraulic conductivity. By the end of injection, the fine grained material had been washed out, leaving larger particles capable of moving solution through the heap much more quickly. Raw instrument data have been used to calculate parameters that can determine the relative rate of energy needed to move a unit volume of solution and the relative change in formation permeability. Our data provided the client with much needed information to optimize the injection process.


HGI provides robust monitoring of well behavior and hydraulics to aid in optimizing injections into leach pads for drawing down metal inventory.

Understanding the hydraulics of heaps, especially during enhanced metal recovery is a unique specialty of HGI. We have overseen many injection projects and can help acquire the requisite data needed to optimize your recovery process.

Ex-Situ Sampling

Water and soil samples sent to an offsite lab can take time. Our on-site analysis can give you the information needed in very short order and provide much needed statistical information about changes occurring within your geochemical system. The data and photos below highlight some of our work with the Mobile Solutions Lab.



Metallurgical data acquired from monitoring of enhanced metal recovery. Metallurgical monitoring of a secondary metal recovery project on a copper mine.