Fig. 5. Effluent ¹³⁷Cs⁺ (A) and U (B) concentration for hydroxyapatite [HA]-amended and unamended Sediment A columns leached with 1.0 mol L^-1 NH₄Cl, 0.001 mol L^-1 CaCl₂, or 0.001 mol L^-1 CaCl₂ + 0.0005 mol L^-1 NH₄Cl. Note that the ¹³⁷Cs⁺ levels for all but the 1.0 mol L^-1 NH₄Cl leachates were below detection limits (<18.6 Bq L^-1) regardless of amendment treatment. Error bars indicate the standard deviation of the means.