Yu. V. Dublyanskii*, J. S. Szymanski**, A. V. Chepizhko***,
B. N. Lapin***, and V. N. Reutskii***
* United Institute of Geology, Geophysics, and Mineralogy, Siberian Division, Russian Academy of Sciences,
Universitetskii pr. 3, Novosibirsk, 630090 Russia
** Technology and Resources Assessment Corporation, North America
*** Odessa State University, Ukraine
Received December 24, 1998
Abstract—The Yucca Mountain in Nevada is the only prospective site for construction of the national geolog-
ical repository of the high-level nuclear wastes and spent nuclear fuel of the United States. The repository is
planned to be located within the aeration zone. Investigations of the silicate–carbonate epigenetic deposits
(veinlets, veins, slope deposits) developed within the aeration zone and at the surface of the Yucca Mountain
point to the existence of a low-temperature hydrothermal system in the geologically recent past (from ~10 to
0.02 Ma ago). Repetition of episodes of the hydrothermal activity in the geological future is highly probable.
New considerations of the Yucca Mountain hydrogeology have crucial significance for assessment of the tech-
nical adequacy of the managed nuclear waste disposal site.