Aqueous characteristics and radionuclides in Peito Hot Spring Area

作者：Lin, Chun Chih^*; Tsai, Tsuey Lin; Liu, Wei Chung; Liu, Chi Chang

来源：Radiation Measurements, 2011, 46(5): 561-564.

DOI：10.1016/j.radmeas.2011.03.003

• Activity concentration
• Hokutolite
• Hot spring
• Radionuclide
• Peito
• Radioactive disequilibrium

Aqueous characteristics and activity concentrations of U/Th-series radionuclides were investigated in the birthplace of hokutolite - the Peito Hot Spring Area in Taiwan. Water samples were taken in 12 locations from the hot spring pond and the Peito Creek in this study. Temperature, acidity and redox potential exhibited similar trends decreasing from the hot spring pond toward downstream Peito Creek. The aqueous environment of this area existed in an acidic and oxidative state and was found influenced by hot spring water drawing and wastewater discharge. Major ions in water were Fe(3+), Ca(2+), Sr(2+), Ba(2+), Pb(2+), Cl(-) and SO(4)(2-), which (except for Ba(2+)) generally varied with sampling locations in a tendency similar to those of temperature, acidity and redox potential. U/Th-series radionuclides were examined by alpha spectrometry while (228)Ra were determined with ICP-QMS. Th-series was found predominant over U-series in this area. Activity concentrations of (238)U (0.09 +/- 0.02 to 2.69 +/- 0.13 pCi/L) and (234)U (0.10 +/- 0.02 to 2.64 +/- 0.13 pCi/L) were similar and the activity ratios for (234)U/(238)U were greater than unity. For (230)Th and (228)Ra, the activity concentrations were respectively 0.07 +/- 0.03 to 0.86 +/- 0.06 pCi/L and 0.17 +/- 0.02 to 1.49 +/- 0.06 pCi/L, which led to activity ratios of (230)Th/(234)U lower than unity while those of most (226)Ra/(230)Th greater than unity. In Th-series, the activity concentrations of (232)Th (0.06 +/- 0.02 to 0.90 +/- 0.06 pCi/L) and (230)Th were similar at the sampling area. Apparent disequilibria were discovered between (228)Ra and (232)Th resulting from abundant (228)Ra (6.01 +/- 0.41 to 10.5 +/- 0.8 pCi/L). The variation for activity concentration of (228)Th (0.43 +/- 0.06 to 9.26 +/- 0.18 pCi/L) with sampling locations was similar to that of (232)Th. However, significant disequilibria were discovered between (228)Th and (232)Th. The reported data contribute to the assessment of radionuclides distribution and the investigation of hokutolite recovery in the studied area.

• 出版日期2011-5
• 单位南华大学