In-Situ Recovery (ISR)
What is In-Situ Recovery?
In-Situ Recovery (ISR) is a modern technique used to extract uranium from sandstone-hosted deposits below the Earth’s surface. This innovative method eliminates the need for open pits, waste rock, and tailings offering a cleaner and more sustainable approach to resource extraction..
The process involves a network of injection and recovery wells that circulate a water-based solution known as a lixiviant, through the uranium-bearing formation. This solution, typically consisting of oxygen and sodium bicarbonate mixed with native groundwater, dissolves the uranium in place without disturbing the surrounding rock. The uranium-enriched solution is then pumped to the surface, where the uranium is separated and processed into a final product.
How Does ISR Work?
In-situ recovery of uranium typically occurs in sandstone formations within aquifers that have been exempted by regulatory authorities from protection as drinking water sources due to naturally occurring minerals like uranium and radium. ISR wellfields are developed using a network of injection and recovery wells. A lixiviant—composed of native groundwater enhanced with oxygen and sodium bicarbonate—is injected into the uranium-bearing sandstone. The oxygen in the lixiviant dissolves the uranium, and the solution is then drawn to recovery wells, which pump it to the surface. At the processing facility, uranium is separated and refined into U₃O₈, or yellowcake. After operations conclude, both the groundwater and surface land are restored to their original quality and designated use, ensuring minimal environmental impact.
Why Choose In-Situ Recovery?
Environmentally Friendly
No open pits, waste dumps, or tailings. ISR leaves the surface landscape largely undisturbed.
Water Conservation
99% of water used is returned to the aquifer during operation.
Lower Carbon Footprint
ISR uses up to 60% less energy than conventional mining methods, reducing greenhouse gas emissions.
Cost-Effective
With reduced surface disruption and simpler permitting processes, ISR is more economical than traditional mining.
Safety Assurance
ISR is regulated to the highest standards to ensure that groundwater and the surrounding environment remain protected.
A Globally Trusted Technology
First introduced in the United States in the 1960s, ISR has since become the leading method of uranium extraction, accounting for approximately 60% of global uranium production. It is widely used in countries such as Kazakhstan, the United States, and Australia. While some international processes still rely on harsh chemicals, most U.S. operations use environmentally responsible lixiviants to minimize ecological impacts.
As we celebrate the 50th anniversary of In-Situ Recovery technology, this innovative method continues to set the standard for minimally intrusive, eco-friendly, and economically competitive mineral extraction. The first commercial scale American ISR uranium project commenced production on April 1, 1975 at the Clay West Project, operated by Atlantic Richfield Company in partnership with US Steel and DALCO. ISR has proven to be a highly successful technique for uranium.