SUITMA soils are characterised by a multitude of different artificial materials (technogenic substrates) such as,for example,slags,ashes,refuse,coal mining waste,sludge and building debris (Meuser & Blume 2001).Consequently increased heavy metal content in comparison with natural soils is evident.In the course of dynamics in pedogenetic processes contaminated anthropogenic soils run the risk of heavy metal leaching into the ground water depending on varying locational conditions (e.g.rainwater percolation,acidification,weathering).Tberefore the following aspects should be taken into account:a) knowledge about the parent material in SUITMA soils From the perspective of geoscientists the determination of natural parent material by using reference keys is part of their everyday work.Unfortunately the application will seldom be successful to describe the composition of technogenic substrates in SUITMA soils.Nevertheless technogenic substrates are characterized by typical,reproducible industrial treatment procedures as well as natural parent material which was deposited under typical "geological treatment" conditions (e.g.fluvial sedimentation).Therefore technogenic substrates may consist of specific compounds,e.g.slags from blast furnaces,and show mostly similar features.The approach to establish a reference key for technogenic substrates (roughly spoken building debris,ashes,slags,mining waste,refuse and sludges) was tested by Meuser (1996) in the Ruhr-Area (Germany) which is superprinted by urban,industrial,traffic and mining land use.b) assessment of heavy metal leaching from SUITMA soils (source strength) Since German Soil Protection Regulation (BBodSchV 1999) was established analyses evaluating the hazard potential of soils and leaching of heavy metals from soils were defined.On the one hand aqua regia extraction is applied to quantify the total potential amount of heavy metal contaminants referring to the pathway soil-human being (direct uptake).Furthermore extraction with this mixture of concentrated acids allows the assessment of the long-term hazard potential in heavy metal leaching from technogenic substrates.On the other hand the H2Odem extraction method is suggested according to BBodSchV (1999) to describe the leaching potential of heavy metals on the pathway from soil to ground water.Careful interpretation is necessary because the soil samples are eluted by shaking or stirring with H2Odem.This may result in incorrect evaluation of heavy metal leaching because the soil is not analysed considering the (natural) site conditions (NTitsche 2002).Therefore the utilization of Dynamic Batch Test (stainless steel near-natural soil columns) on technogenic substrates is recommended.Simultaneous observation of pH-value-,redox potential-and electrical conductivity-dynamics within 24h-circular percolation may be stressed out as the advantages towards other time consuming techniques (Makowsky et al.2004).