Groundwater quantity and quality depends upon the sources of its budget formation. If we know the concentrations of certain specific indicators in the sources, we can calculate their input into the budget of abstracted groundwater. Because most of those indicators are neither specific nor stable, hydrochemical studies of Vilnius wellfields were supplemented by some isotope (helium He, tritium ³H, radiocarbon ¹⁴C) methods. Results of isotope studies show that only the He-method is adequate for identification of saltwater intrusion and calculations of groundwater budget in Vilnius wellfields. In Vilnius wellfields this input was found to vary within 9–10% up to 30–35%.Almost the same result was
obtained using the hydrochemical Cl-method and groundwater simulation. Atmospheric radiocarbon and tritium are suitable only for indicating surface water inflow.

Issues:

2011 - Vol.53
No. 1, No. 2, No. 3

2010 - Vol.52
No. 1-4

2009 - Vol.51
No. 1-2, No. 3-4

2008 - Vol.50
No. 1, No. 2, No. 3, No. 4, No. Priedas

2007
No. 1, No. 2, No. 3, No. 4

2006
No. 1, No. 2, No. 3, No. 4

2005
No. 1, No. 2, No. 3, No. 4

2004
No. 1, No. 2, No. 3, No. 4

2003
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2002
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2001
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