The department's U.S. Geological Survey also released a letter from the panel that reveals the scientists' names for the first time, the Associated Press reported.
The letter sent Thursday by Rep. Jon Porter, R-Nev. -- who chairs a House Government Reform subcommittee looking into the matter -- requests the presence of Joe A. Hevesi, Alan L. Flint and Lorraine E. Flint "to meet with subcommittee staff regarding statements contained in the e-mails in question."
Only redacted versions of the e-mails have been made public, and so it was not possible to tell what role Hevesi or the Flints had. Subcommittee staffers declined to elaborate. All are listed on USGS Web sites as research hydrologists in Sacramento, Calif.
The FBI and the inspectors general at the Interior and Energy departments are investigating the possibility of fraudulent work on the nuclear waste repository, and the Interior Department cited the investigations in turning down Porter's request for the scientists' presence at Wednesday's hearing.