Characterization of uranium contaminated soils from DOE Fernald Environmental Management Project Site: Results of Phase 1 characterization

Abstract

The Integrated Demonstration (ID) for remediation of uranium- contaminated soils has been established by the DOE Office of Technology Development. The Fernald (Feed Materials Production Center) site was selected as the DOE facility for the field demonstration. The principle objective of this ID is to evaluate and compare the versatility, efficiency, and economics of various technologies that may be combined into systems for the removal of uranium from contaminated soils. Several leaching solutions were employed to determine their effectiveness in extracting uranium from the soil. The extractants and their means of preparation were: 0.1 N nitric acid (HNO{sub 3}): 6.25 mL of concentrated nitric acid was diluted to 1 L with distilled water; 2% ammonium carbonate ((NH{sub 4}){sub 2}CO{sub 3}): 20 g of (NH{sub 4}){sub 2}CO{sub 3} was dissolved in distilled water and diluted to 1 L; 5% sodium hypochlorite (NaOCl): 50 mL of NaOCl reagent (Cl < 6%) was diluted to 1 L with distilled water; 0.1 M ethylenediaminetetraacetric acid, disodium salt (EDTA): 37.224 g EDTA was dissolved in distilled water and diluted to 1 L; 2% citric acid monohydrate solution (H{sub 3}C{sub 6}H{sub 5}O{sub 7}{center dot}H{sub 2}O): 20 g of critic acid was diluted to 1 L with distilled water; 0.1 M hydroxylamine-hydrochloride (NH{sub 2}OH{center dot}HCl) in 0.01 N nitric acid: 6.95 g (NH{sub 2}OH{center dot}HCl) was dissolved and diluted to 1 L with 0.01 N HNO{sub 3}. The 0.01 N nitric acid was prepared by diluting 3 mL concentrated nitric acid to 5 L with distilled water; and the sodium citrate-bicarbonate-dithionite (CBD) method: 0.3 M sodium citrate (88 g tribasic sodium citrate, Na{sub 3}C{sub 6}H{sub 5}O{sub 7}{center dot}2H{sub 2}O, per liter); 1 M sodium bicarbonate (84 g NaHCO{sub 3} per liter); and 5 g sodium dithionite, Na{sub 2}S{sub 2}O{sub 4}.