Sorption phenomena of nitroaromatic compounds in geochemical variable soils represented on the basis of column tests under in-situ conditions

Groundwater in the discharge area of former ammunition production facilities often reveals severe contamination by production residues and waste products. Thus, these can effect a health hazard to human beings in cases where untreated water is consumed. Based on a case study of a more than 1.5 km elongated contamination plume, column tests were carried out for determining the mechanisms of transportation. By using local soils taken in undisturbed cores and the contaminated local groundwater consisting of TNT, DNT, DNB, TNB, ADNT and DNN, in-situ conditions were created. Previous investigations showed that the sorption strongly correlates with the content of clay and organic matter in the soil; recent investigations additionally show the existence of complex interactions in the pristine multi-compound systems investigated. In compliance with the percentage composition of,clay and organic matter, various breakthrough-curves were obtained, which imply different sorption phenomena, e.g., competitive adsorption. In particular, step-like breakthrough-curves have to be emphasised as extraordinary phenomenon.