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The Tyrolean Iceman, a 5,300-year-old glacier mummy recovered at the Tisenjoch (South Tyrol, Italy) together with his clothes and personal equipment, represents a unique opportunity for prehistoric research. The present work examines the Iceman's tools which are made from chert or are related to chert working - dagger, two arrowheads, endscraper, borer, small flake and antler retoucher - and considers also the arrowhead still embedded in the shoulder of the mummy. The interdisciplinary results achieved by study of the lithic raw material, technology, use-wear analysis, CT analysis and typology all add new information to OÈtzi`sindividual history and his last days, and allow insights into the way of life of Alpine Copper Age communities. The chert raw material of the small assemblage originates from at least three different areas of provenance in the Southalpine region. One, or possibly two, sources derive from outcrops in the Trentino, specifically the Non Valley. Such variability suggests an extensive provisioning network, not at all limited to the Lessini mountains, which was able to reach the local communities. The Iceman's toolkit displays typological characteristics of the Northern Italian tradition, but also comprises features typical of the Swiss Horgen culture, which will come as no surprise in the toolkit of a man who lived in a territory where transalpine contacts would have been of great importance. OÈtzi was not a flintknapper, but he was able to resharpen his tools with a medium to good level of skill. Wear traces reveal that he was a right-hander. Most instruments in the toolkit had reached their final stage of usability, displaying extensive usage, mostly from plant working, resharpenings and breaks. Evidently OÈtzi had not had any access to chert for quite some time, which must have been problematic during his last hectic days, preventing him from repairing and integrating his weapons, in particular his arrows. Freshly modified blade tools without any wear suggest planned work which he never carried out, possibly prevented by the events which made him return to the mountains where he was killed by a Southern Alpine archer.

Microbial removal of the poorly degradable antibiotic sulfamethoxazole (SMX) from surface water was investigated in laboratory columns to identify critical factors for SMX removal during bank filtration, such as the substrate concentration, redox conditions and the availability of biodegradable DOC. About 60% of SMX at a start concentration of 0.25 μg/L in surface water were removed within 14 d of column passage under aerobic conditions while no removal occurred under anoxic conditions. The adaptation time was very long and was not completed after 2 years of operation. Adaptation was faster and SMX degradation was improved at an elevated concentration of SMX (4.5 μg/L) with 90% removal in 3.5 d under aerobic conditions. SMX removal was less effective under anoxic conditions (27% in 14 d) but increased again under anaerobic conditions (51% in 14 d). According to the half-lives for SMX determined from the column data (1-9 d aerobic, 49 d anoxic and 16 d anaerobic) it is essential to provide several weeks up to months of travel time in bank filtration to allow for the degradation of SMX, and likely, also for other poorly degradable compounds. Thus, the occurrence of SMX in groundwater samples does not indicate persistency of SMX but reflects insufficient residence time or unfavorable respective redox conditions. Adaptation times of years may also be required for new bank filtration sites to develop their full removal potential towards trace pollutants. Long operation time, a comparable concentration level and similar redox conditions as in the field appear to be essential to obtain realistic results with laboratory column experiments that can be transferred to real bank filtration sites.

Adsorption of arsenate, phosphate, salicylic acid, and groundwater DOC onto granular ferric hydroxide (GFH) was studied in batch and column experiments. Breakthrough curves were experimentally determined and modelled using the homogeneous surface diffusion model (HSDM) and two of its derivatives, the constant pattern homogeneous surface diffusion model (CPHSDM) and the linear driving force model (LDF). Input parameters, the Freundlich isotherm constants, and mass transfer coefficients for liquid- and solid-phase diffusion were determined and analysed for their influence on the shape of the breakthrough curve. HSDM simulation results predict the breakthrough of all investigated substances satisfactorily, but LDF and CPHSDM could not describe arsenate breakthrough correctly. This is due to a very slow intraparticle diffusion and hence higher Biot numbers. Based on this observation, limits of applicability were defined for LDF and CPHSDM. When designing fixed-bed adsorbers, model selection based on known or estimated Biot and Stanton numbers is possible.

Adsorption onto granular ferric hydroxide (GFH) with subsequent in-situ regeneration is studied as a new process for natural organic matter (NOM) removal from groundwater. Adsorbent equilibrium loadings of 10-30 mgDOC g(-1)GFH(-1) are obtained, whereas the non-adsorbable DOC fraction amounts to 1.5 mgL(-1) for all investigated groundwaters. The larger and UV-active NOM fractions (mainly fulvic acids) are well adsorbed while the smaller molecular fractions are poorly or not adsorbed. However, kinetic studies show that the smaller and medium-sized fulvic acids are removed first. The equilibrium is strongly dependent on pH but only weakly on ionic strength, pointing to ligand exchange as the dominant adsorption mechanism. With regard to NOM structure, prerequisites for adsorption onto GFH are both a minimum number of functional groups and a molecular size small enough to enter the GFH pores. NOM breakthrough curves are successfully simulated using the LDF model (homogeneous surface diffusion model (HSDM) with linear driving force approach for surface diffusion) and experimentally determined mass transfer coefficients. Regeneration of loaded GFH is possible either by use of NaOH or oxidatively by H(2)O(2). The optimal quantities and concentrations are determined.