Organic fractions and metal-organic complexes in the groundwater

Natural organic matters are widely used in both surface and underground waters, which are prepared as drinking water. The organic matter are divided into four fractions: very hydrophobic acids (VHA), slightly hydrophobic acids (SHA), hydrophilic charged (CHA) and hydrophilic neutral (NEU). Organic matters are negatively charged so they form complexes with metals. For the determination of organic fractions and metal organic complexes rapid fractionation technique is used. Researches were made in Nida and Preila (III group (open)), Taujenai and Petronys (II group (semi-closed)) water well fields. After fractional studies were made it showed that 90 % of all organic compounds composed of very hydrophobic acids (VHA) and slightly hydrophobic acids (SHA) which consist of a large molecular weight compounds. Over 90 % of bivalent iron composed complex compounds with hydrophobic organic matters. Manganese does not entirely complexes with organic compounds.