Dear Mr. Cook,
Thank you for posting your request on History Hub!
There may be records on this topic in the Records of the U.S. Bureau of Mines (Record Group 70) and the Records of the Bureau of Land Management (Record Group 49) in the custody of the National Archives in Washington, DC - Textual Reference (RDT1) (Archives1reference@nara.gov), the National Archives at Denver (RM-DV) (firstname.lastname@example.org), the National Archives at College Park - Textual Reference (RDT2) (Archives2reference@nara.gov). Please email these units for further information. In your reference inquiries, please be as specific as possible about the time periods, locations, company names, mine owner names, etc. that you are researching and the type of information you seek to find.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT1, RM-DV and RDT2. We apologize for this inconvenience and appreciate your understanding and patience.
You also may wish to contact state and local archives, libraries, historical societies, and museums.
We hope this is helpful. Best of luck with your research!