Introduction

The U.S. Geological Survey (USGS) operates a low-enriched uranium-fueled, pool-type reactor located at the Federal Center in Denver, Colorado. The mission of the Geological Survey TRIGA^® Reactor (GSTR) is to support USGS science by providing information on geologic, plant, and animal specimens to advance methods and techniques unique to nuclear reactors. The reactor facility is supported by programs across the USGS and is organizationally under the Associate Director for Energy and Minerals, and Environmental Health. The GSTR is the only facility in the United States capable of performing automated delayed neutron analyses for detecting fissile and fissionable isotopes. Samples from around the world are submitted to the USGS for analysis using the reactor facility. Qualitative and quantitative elemental analyses, spatial elemental analyses, and geochronology are performed. Few research reactor facilities in the United States are equipped to handle the large number of samples processed at the GSTR. Historically, more than 450,000 sample irradiations have been performed at the USGS facility. Providing impartial scientific information to resource managers, planners, and other interested parties throughout the world is an integral part of the research effort of the USGS.

The USGS TRIGA^® reactor has been in operation since the late 1960s in support of nuclear-based research for the USGS and a number of universities across the Nation. It is the only research reactor of its type in the Department of the Interior and the only research reactor within a 350-mile radius of Denver, Colo. The reactor design is similar to research and training reactors at universities throughout the United States. The reactor provides an intense neutron source for experiments and is capable of continuous steady-state operation at 1,000 kilowatts (thermal). Also, it may be pulsed to a peak power of approximately 1,600 megawatts. Services include, but are not limited to, neutron irradiations for argon isotopic dating, neutron activation analysis, uranium and thorium analysis by delayed neutron counting, radioisotope production, gamma spectrometry, and fission track experiments.

First posted July 17, 2012