This Bureau of Mines report discusses uranium in situ leach mining in the United States to acquaint the public with an overview of this emerging mining technology. This report is not intended to be a technical discussion of the subject matter, but rather should be used as a reference source for information on in situ leaching. A list of in situ leaching publications is included as well as engineering data tables for almost all of the active pilot-scale and commercial uranium in situ leaching operations. These tables represent a first attempt at consolidating operational data in one source, on a regional basis. Additional information is given that discusses the current Bureau of Mines uranium in situ leaching research program. Also included is a listing of various state and federal permitting agencies, and a summary of the current uranium in situ leaching operations. Finally, a glossary of terms has been added, listing some of the more common terms used in uranium in situ leach mining.