Here is some great information and reading. Please follow link. Their are many operations reports available too many to list do have a ship name that he was on during this operation, I could search the site.
Dear Mr. Bullard,
Thank you for posting your request on History Hub!
We suggest that you request a copy of his Official Military Personnel File (OMPF). OMPFs and medical records of enlisted men and officers of the U.S. Navy and the U.S. Air Force who were separated from the service after 1958 and are located at NARA's National Personnel Records Center (NPRC), (Military Personnel Records), 1 Archives Drive, St. Louis, MO 63138-1002. To request these records, please mail a completed GSA Standard Form 180 to NPRC. Next of kin also may use eVetRecs to request records. See eVetRecs Help for instructions. Certain information in the records is not available to the general public without the written consent of the veteran or his next of kin. For more information see Request Military Service Records.
We searched the National Archives Catalog and located a number of records related to Operation Crossroads. Some of these records have been digitized and may be viewed through the Catalog. To inquire about the records not yet digitized, please email the reference unit listed as the contact in the Catalog Description.
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 the National Archives. Also, the National Personnel Records Center is servicing only urgent requests related to homeless veterans, medical emergencies, and funerals which may be faxed to 314-801-0764. We thank you for your patience and look forward to resuming normal operations when the public health emergency has ended.
We searched the website of the Naval History and Heritage Command and located a number of items related to Operation Crossroads. You may also be interested in the U.S. Department of Energy’s page on Operation Crossroads and the 1984 report on Operation Crossroads available on the website of the Defense Threat Reduction Agency (DRTRA).
We hope this information is helpful. Best of luck with your family research!