In-Situ Recovery (ISR)

What is In-Situ Recovery?

In-Situ Recovery (ISR) offers a minimally intrusive, eco-friendly, and economically competitive approach to mineral extraction. It’s been proven a successful technique for obtaining uranium, especially from lower-grade deposits that might not warrant conventional open pit or underground mining due to costs. Unlike traditional mining, ISR doesn’t involve open pits, waste dumps, or tailings, making it more environmentally considerate. This method also streamlines the permitting, development, and remediation processes. With ISR, uranium is extracted without disturbing the surface, and once the process is complete, the land is restored to its original state and purpose.

Since its appearance in the 1960s, ISR technology has evolved significantly. Today, it’s a controllable, safe, and benign uranium production method that is highly regulated in the United States Today, ISR accounts for about 70% of global uranium production. Some nations, like Kazakhstan and Australia, still employ strong chemicals like sulfuric acid for extraction. Many companies in the United States opt for a mix of oxygen and sodium bicarbonate in the local groundwater, which extracts uranium with minimal environmental impact and at a near-neutral pH.

Aquifer Exemption Zone

ISR was commercially introduced in the uranium sector during the 1970s in the USA, and then applied in many countries over the last 50 years.

ISR allows the extraction of minerals leaving the host rocks ‘in place’. No waste piles, haul trucks, tailings or long-term disturbance.

enCore Energy’s Director, Dr. Dennis Stover, PhD, was awarded several of the first ISR patents in the United States and was instrumental in the technology.

How Does It Work?

In-Situ Recovery (ISR) is a method for extracting minerals by infusing a water-based solution, called a lixiviant, into the ground. This technique eliminates the need for traditional mining and uses minimal groundwater. Typically, ISR targets uranium in sandstone deposits. These deposits are often in areas of aquifers that aren’t suitable for drinking water due to their mineral content of uranium, radium, and other elements. To carry out ISR, a wellfield is set up with a pattern of injection and recovery wells. The injection well pumps in the lixiviant, which is local groundwater enriched with oxygen and sodium bicarbonate. This solution travels through the uranium-rich sandstone, solubilizing the uranium with the help of the oxygen. The lixiviant, now bearing the uranium, is then drawn out through the sandstone to the recovery well. This extracted solution is taken to a facility and is processed to separate the uranium, eventually producing U3O8, otherwise known as yellowcake. ISR has been a trusted method globally for over 50 years with minimal environmental consequences. After an ISR project concludes, both the land and groundwater are returned to their original state and purpose.
ISR Central Processing Plant

A multiple jurisdictional state and federal regulatory regime ensures that no solution escapes from the ISR area and ground water is protected.

According to the U.S. Nuclear Regulatory Commission there has never been a drinking water supply contaminated by ISR in the 50 years since its inception.

ISR facilities use less water than conventional mining and return 99% of water used to the aquifer (not used for drinking water or livestock).