Near-conservative behavior of I-129 in the orange county aquifer system, California
Published in:
Applied Geochemistry 20,8 (2005) 1461-1472;
Abstract
Iodine is a biophilic element, with one stable isotope, I-127, and one long-lived radioisotope, I-129. Radioiodine originates in the surface environment almost entirely from anthropogenic activities such as nuclear fuel reprocessing in Europe and thus provides a unique point source tracer. Very few studies have evaluated the geochemical behavior of I isotopes in the subsurface. In this study, the concentrations of I-129 and I-127 were measured in wells fed by a series of artificial recharge ponds in the Forebay Area of the Orange County ground water basin (California, USA) to evaluate their potential use as hydrological tracers. To substantiate interpretation of I-129 and I-127 concentration data, the aquifer system was evaluated using the literature values of aquifer water mass age based on H-3/He-3, Xe and delta(18)O tracer data. The aquifer data demonstrate the nearly conservative behavior of I-129 with I-129/I-127 ratios likely reflecting variations in source functions as well as climatic conditions, and with inferred particle-water partition coefficients (K-d) of 0.1 cm(3) g(-1) or less. (c) 2005 Published by Elsevier Ltd.
Keywords
fuel reprocessing facilities;; oceanographic tracer;; artificial recharge;; humic substances;; organo-iodine;; water;; sorption;; environment;; chlorine;; chromatography
Date of this Version
January 2005