EFFECTS OF OZONE TREATMENT ON THE SOIL ORGANIC-MATTER ON CONTAMINATEDSITES

In recent years, the ozone treatment technique has been discussed for remediation of contaminated sites. In this paper, data on the effects of ozonation of soil organic matter in ground and pore waters are pres ented. An aqueous soil extract was ozonated in a stirred tank reactor and characterized by size-exclusion chromatography with online UV and dissolved organic carbon detection. Additionally, degradation experime nts were carried out with these extracts in a bacteria regrowth measur ement system. After ozonation, a decrease of the humic acid fraction a nd a reduction of its average molecular size could be recognized. In c ontrast to this, there was an increase of the building block fraction and the low molecular acid fraction. These two fractions were readily degradable by microorganisms. Therefore, the bacteria regrowth increas ed with ozonation time. As a result of this, a fast and high regrowth of bacteria can be expected after the ozone remediation technique has been applied. The UV absorbance of extracts at a wavelength of 254 nm showed no significant changes before and after biological degradation. It can be supposed that the microorganisms were not able to degrade c hromophoric groups absorbing at a wavelength of 254 nm. (C) 1998 Publi shed by Elsevier Science Ltd. All rights reserved.