The 222Rn, 3H and stable isotopes as tracers of groundwater-surface water interactions in a stream basin

Natural isotopes such as 222Rn, 3H, 18O and D were used to understand the groundwater-surface water interactions and these tracer showed surface water intrusion effect during the winter. The 222Rn concentrations of samples retrieved from the multi-depth well varied with sampling point and time, e.g. they decreased by about 80 % during the winter. The results of the analyses of stable isotopes show that the mean δ 18O value was -7.84 ‰ (-9.16 ‰ to -7.24 ‰), while the mean δD value was -54.13 ‰ (-57.86 ‰ to -50.98 ‰). The 3H groundwater concentrations ranged from 0.23 to 0.59 Bq/L, with an average value of 0.37 Bq/L. (author)