Soil and groundwater protection

Slovnaft's refinery and petrochemicals complex is situated in an area of protected natural water, Žitný Island. The protection against pollution of this area with its natural groundwater reserves has always been a matter of public interest.

To protect soil and groundwater, Slovnaft has been operating a groundwater hydraulic protection system (GWHP) since 1973. The GWHP system's core consists firstly of a hydraulic aperture with two lines of pumping wells, located along the entire eastern boundary of the refinery complex, the inner line located directly in the area, the external one outside and secondly individual pumping wells in the Slovnaft complex, located in areas with the highest concentration of pollution. In addition, three systems monitor the hydraulic and hydro chemical parameters of the environment. These parameters are feedback for the GWHP system itself.

The GWHP’s main function is to create a decline in groundwater levels under Slovnaft's manufacturing area so that the organic load is concentrated below the surface. The pumping of groundwater in the vicinity of a well leads to reduction in water levels into which free oil substances flow. These are pumped out from groundwater levels using a separate pump and returned for further processing to the production units. Continuous GWHP system operations have ensured that oil pollution, which, in the past, occurred behind the refinery complex, was eliminated from the refinery's vicinity and oil products are currently located just below the plant itself.

The annual amount of pumped groundwater is about 30 million m³, about a quarter being used as a production cooling agent. The total volume of pumped water is returned to the natural environment after purification.

In addition to the refinery itself, Slovnaft is implementing a programme for the removal of environmental burdens at storage depots and Service Stations.