Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain site characterization study. Progress report, October 1, 1994--December 31, 1994

The bromide anion has been used extensively as a tracer for mapping the flow of groundwater. It has proven to be both a safe and reliable groundwater tracer. The goal in this study is to find several tracing compounds with characteristics similar to the bromide anion to be used in multiple well tracing tests. Four groups of fluorinated organic acids were selected as candidates for groundwater tracers. These groups include fluorinated benzoic acids (FBA), fluorinated salicylic acids (FSA), fluorinated toluic acids (FTA), and fluorinated cinnamic acids (FCA). These compounds have been shown to move readily with the flow of water and do not adsorb to soil. They are also non-toxic. In this study, the retention of the fluorinated organic acids on to a soil column is compared to that of the bromide ion. The time required for the elution of each analyte from the soil column is measured using a UV-Vis detector. The soils consist of the light, medium, and dark tuffs used in the batch study. The work performed during this quarter consists of the continuation of the batch studies for the fluorinated benzoic acids and column studies for several potential tracer compounds