A groundwater monitoring of economic entities in Lithuania is carried out more than twenty years, though the legal basis for it was created in1997.

Based on conditions of issued IPPC economic entities have to monitor their environment, including groundwater. After coordination with Regional Environment Departments, the Lithuanian Geological Survey approves groundwater monitoring programs, prepared for economic entities. Groundwater monitoring data are provided to Geological Survey of Lithuania and to Regional Environment Departments and, in demand – to municipalities. Lithuanian Geological Survey published methodical recommendations for monitoring programs arrangement and manages information system of monitoring data.

A monitoring of economic entities is obligatory for:

• potential polluters of underground;

• groundwater consumers (>100m3/day).

Up till now, 1500 groundwater monitoring programs for economic entities were confirmed. The most active are well fields (water users) and petrol stations.