The Identification and Quantification of Gnome-Derived Radionuclides in WIPP Environmental Samples


Thomas B. Kirchner

Barry Stewart

Joe Fraire

Carl Schloesslin


Carlsbad Environmental Monitoring and Research Center

New Mexico State University

Carlsbad, NM


In 1961, an underground nuclear test, the Gnome project, was conducted approximately 9 km southwest of the present-day WIPP facility. The explosion vented to the surface resulting in considerable contamination of the surrounding area. Two attempts were made at cleanup, in 1968-69, and in 1978. However, there are still areas that have elevated levels of radionuclides. The presence of these contaminated areas poses a potential source of contamination of WIPP environmental samples. For that reason, a study was undertaken to determine whether or not a "fingerprint" or "signature" exists that could identify Gnome-derived material. The research plan included the determination of ratios of plutonium isotopes, ratios of other radionuclides, and ratios of non-radioactive elements.

Because of the possibility of the presence of refractory plutonium, a method was developed for total dissolution of 10-gram samples of soil. This presentation describes the details of the dissolution process used for Pu-Am samples; a brief overview of the separation methods; and some preliminary results for actinide elements.