Heap Leach and Ion-Exchange Facilities

Through the years, the U.S. Nuclear Regulatory Commission (NRC) has licensed numerous uranium recovery facilities in the United States, which used a variety of extraction methods. In addition to conventional uranium milling and in situ recovery (ISR), which are currently used to extract uranium from ore, some NRC-licensed facilities used extraction methods known as heap leaching or ion-exchange. Such facilities no longer operate and are in the process of decommissioning. Nonetheless, heap leaching has also been used to extract uranium from ore at conventional mills, and ion-exchange procedures have been used to separate uranium from the liquid extract at both conventional mills and ISR facilities.

Heap leach/ion-exchange operations involve the following process:

1. Small pieces of uncrushed ore are placed in a "heap" on an impervious pad of plastic, clay, or asphalt, with perforated pipes under the heap.

2. An acidic solution is then sprayed over the ore to dissolve the uranium it contains.

3. The uranium-rich solution drains into the perforated pipes, where it is collected and transferred to an ion-exchange system.

4. The ion-exchange system extracts and concentrates the uranium to produce a material, which is called "yellowcake" because of its yellowish color.

5. Finally, the yellowcake is packed in 55-gallon drums to be transported to a uranium conversion facility, where it is processed through the stages of the nuclear fuel cycle to produce fuel for use in nuclear power reactors.