T.M. Beasley, Environmental Measurements Laboratory, NY, NY

L.D. Cecil, L.J. Mann, USGS Idaho Falls, ID

P. Sharma, U. Fehn, H.E. Gove, University of Rochester

P.W. Kubik, Scherrer Institute, Zurich Switzerland

Gound Water 31 (1993) 302-310

Between 1952 and 1984, low-level radioactive waste was introduced directly into the Snake River Plain aquifer at the Idaho National Engineering Laboratory (INEL), Idaho Falls, Idaho. These wastes were generated, principally, at the nuclear fuel reprocessing facility on the site. Our measurements of 36Cl in monitoring and production well waters, downgradient from disposal wells and seepage ponds, found easily detectable, nonhazardous concentrations of this radionuclide from the point of injection to the INEL southern site boundary. Comparisons are made between 3H and 36C1 concentrations in aquifer water and the advantages of 36Cl as a tracer of subsurface-water dynamics at the site are discussed.