SAS offers assistance in saving the groundwater at Žitný ostrov
Slovakia has the largest natural groundwater reservoir in Central Europe - Žitný ostrov. At current average consumption, it can supply more than 16 million inhabitants. Žitný ostrov is directly and unstoppably endangered by massive chemical pollution, especially waste from production in the former Chemical Plants of Georgi Dimitrov, but also by other industrial activities in Bratislava. SAS researchers have designed a unique waste-free groundwater treatment technology in Vrakuňa and are ready to give a helping hand in solving this socially very important task.
Scientists from the Slovak Academy of Sciences carry out modern research focused on current global challenges associated with the climate crisis. They pay special attention to the development of complex technological procedures for the elimination of environmental burdens and the restoration of polluted areas. Since 2017, research at the SAS has also been dealing with the issue of landfill remediation in Vrakuňa. The nature of the pollution of this site requires the application of advanced physical-chemical and biological processes in groundwater treatment technology.
Experts in this field are scientists from the Institute of Geotechnics SAS in Košice, who, thanks to the coordination of the international project called Water and Soil Clean-up from Mixed Contaminants - WaSClean in 2013-2017, gained significant results in basic research and important know-how which they can apply in the case of environmental burden remediation in Vrakuňa. Subsequently, together with scientists from Comenius University, they tested various methods of treatment of real water samples from the Vrakuňa landfill. The project was financially supported by the Bratislava Self-Governing Region, and, after its completion, the Institute of Geotechnics SAS continued the research, which it financed from its own resources.
“The main method of our proposed technology is electrochemical oxidation, which is suitable for the treatment of waters containing substances that are difficult to decompose and are highly toxic. Its main advantage is that it does not use any chemicals, only electricity. Electrochemical processes are described as environmentally friendly because the electron itself is considered a “pure”, safe and very effective reagent,” explained Daniel Kupka, Head of the Department of Mineral Biotechnologies at the Institute of Geotechnics SAS.
The SAS researchers thus come up with a solution to the most demanding task of landfill remediation. Their filtration technology can be used after the construction of an underground and surface sealing layer, which will isolate the landfill in Vrakuňa. The pumping and treatment of the water accumulated in this body will stop the toxic cloud, which today flows at a speed of 300-500 meters per year and is directed to the densely populated, agricultural and water management area.
“Water pumping must be carried out on a long-term basis, i.e. for decades, in order to maintain a reduced groundwater level and create a hydraulic depression in the body of the landfill. This will prevent contaminated water from flowing out of the landfill. Water is infiltrated in small amounts through the sealing elements into the body, but no more water will flow out of it into the outside environment. From the professional point of view, the most complicated part of the remediation task (CHZJD landfill) is the design and implementation of a technically and financially efficient method of long-term water treatment from the landfill body,” emphasised the biochemist and concluded: "We welcome the interest of the Ministry of Environment of the Slovak Republic in resolving the situation in Vrakuňa and we are ready to give a helping hand, but in order to bring our research to greater operational dimensions, additional funding is needed.”
Edited by Katarína Gáliková
Foto: Daniel Kupka, Pavol Siman