Metal Concentrations in the River Glatt and in Groundwater.
In Table 1, the changes of the concentrations of the major
ions, the metals, and EDTA during infiltration are given. The
wells GW2 and GW3 have for all parameters similar con-centrations as the deep groundwater and are different from
the river and the wells GW1 and GW4. GW1 and GW4 are
lying on a direct flow path, while the water of the two other
wells seems to consist mainly of deep groundwater. Boron
can be used as a tracer for anthropogenic influence, because
it is not eliminated during bank filtration of river water (31).
A dilution factor of metal concentration in the wellican be
expressed as a ratio to boron, referred to the river: