SUN Rui-gang 1, 2, LI Lian-xiang 1, 2, CHENG Xian-jun 1, 2, TIAN Ke-jun 3, LI Xiao-qin 1, 2

1. China Institute of Water Resources and Hydropower Research, Beijing 100048, China
2. National center for Efficient Irrigation Engineering and Technology Research, Beijing 100048, China
3. Lang fang Water Authority, Lang fang 065000, China

Abstract: In order to clarify the distribution and hydrochemistry characteristics of high-fluoride groundwater in Wen’an city, Hebei province, based on hydrogeological investigations and water samples analysis, hydrochemistry status analysis, multivariate statistical analysis and geochemical modeling have been carried out in this paper. Results show that the fluoride concentration ranges from 0.56 mg/L to 4.19 mg/L with 99% of the samples exceeding the maximum allowable limit (1.0 mg/L), pH values range from 7.7 to 8.7, the values of total alkalinity and hardness ranges from 211 mg/L to 296 mg/L and 4 mg/L to 90 mg/L and all the high-fluoride groundwater belongs to Na-HCO 3 type. A positive correlation between total alkaline, bicarbonate, sodium and fluoride indicates that the hydrochemistry status promotes the formation of high-fluoride groundwater. Ca2+ plays a reverse role in fluorite dissolution when fluoride concentration ranges from 2.0 mg/L to 3.5 mg/L. With regard to the occurrence of fluoride, geochemical modeling indicated that cation exchange between the groundwater and the surrounding minerals and mineral weathering and dissolution are major determinants in this region.

Key words: Wen'an city, high-fluoride groundwater, distribution, hydrochemistry

Published in: Journal of China Institute of Water Resources and Hydropower Research (Vol. 12 No. 3, 2014)