March 16, 2022

How Does the ISR Uranium Mining and the ISR Process Work?

Uranium was largely utilized as a colorant in ceramic glazes and for tinting in early photography for many years. It wasn’t until 1866 that its radioactive qualities were discovered, and it wasn’t until the mid-20th century that its potential for use as an energy source was realized. 

Uranium is presently utilized to fuel commercial nuclear reactors that generate electricity and create isotopes used worldwide in medical, industrial, and defense applications.

Uranium is extracted commercially from uranium-bearing minerals such as uraninite, which occurs naturally in low amounts in soil, rock, and water. Open pits and underground excavations can both be used to harvest uranium ore. 

After that, the ore can be crushed and treated in a mill to extract the valuable uranium. Uranium can also be dissolved and pumped to the surface directly from ore deposits in the earth (in-situ leaching). Uranium oxide concentrate (U3O8 ) is created by storing, handling, and selling uranium obtained from the soil.

Conventional mining entails digging up mineralized rock (ore), breaking it up, and processing it to extract the desired minerals.

Uranium ISL 

In situ leaching (ISL), also known as solution mining or in situ recovery or ISR uranium in North America, involves dissolving the ore and pumping the pregnant solution to the surface, where the minerals can be collected. 

As a result, there is a minimum surface disturbance, and no waste rock or tailings are produced. On the other hand, the orebody must be permeable to the liquids utilized and situated so that they do not contaminate groundwater elsewhere.

Uranium ISL uses the orebody’s native groundwater, which has been reinforced with a complexing agent and, in most cases, an oxidant. It is then pumped through the subterranean orebody, leached to recover the minerals. The uranium is retrieved the same way as any other plant after the absorbent solution is returned to the surface (mill).

Because the host aquifers include considerable amounts of acid-consuming minerals like gypsum and limestone, ISL mines in the USA use an alkali leach. If there are more than a few carbonate minerals, alkali leach must be employed instead of acid leach, which is more efficient. Lance, a US ISL mine, intends to use acid leach, proven far more effective in experiments.

The ISR Process

Solution approaches include the In-Situ Recovery (ISR) process. It is vastly different from traditional uranium recovery methods. 

With an ISR uranium production company, the approach avoids the movement and milling of large amounts of rock and ore and the mill tailing waste that more traditional processes entail. It is often less pricey and less harmful to the environment than traditional approaches. 

Historically, open-pit surface mines or underground processes produced the majority of uranium in the United States.

In the mid-1960s, the ISR process was tested for uranium production for the first time, and in 1975, it was put to a commercial-scale plant in South Texas. By the late 1970s, it had established itself in South Texas, where it was used in around twenty commercial projects, two of which we managed.

Groundwater enriched with oxygen and other solubilizing chemicals is poured into a porous ore body in the ISR process, causing the uranium in the ore to dissolve.

The solution is then pushed to the surface. The uranium-bearing fluid is then cycled to a surface ion exchange column, where it is removed from the fluid and immobilized on resin beads. After that, the fluid is re-injected into the ore body.

When the resin beads in the ion exchange column get loaded with uranium, they are removed and flushed with a salt-water solution, which removes the uranium. The uranium is left in a slurry, subsequently dried and packaged as uranium concentrates for export.

It is best to use a well field-specific remote ion-exchange methodology rather than a central facility for improved operating efficiency and cheaper capital expenditures when establishing new well fields.

Rather than transporting the solutions over long distances in large diameter pipelines and mixing the waters of several well fields, each well field is mined utilizing a separate satellite ion exchange station. Ion exchange can now occur at the well field rather than the central plant. 

A well field comprises a sequence of injection, production (extraction), and monitoring wells drilled in a specific pattern. The well field pattern is critical for lowering costs and increasing production efficiency.


The uranium mining business was the first to see success using ISR. An ISR uranium company has a global uranium production share. It’s one of the most fruitful ways to lower the cost of production for specific natural resources. These economic and environmental benefits are the primary drivers of mining worldwide. Non-first-world countries may be able to compete with other world participants in uranium mining due to these advantages. The riches it can bring to a country can transform its economy and create more jobs for its citizens.

enCore Uranium is a domestic uranium developer in the United States to become a major In-Situ Recovery or ISR uranium production company. Browse through our website for more information.