The project Aquisafe assesses the potential of selected near-natural mitigation systems, such as constructed wetlands or infiltration zones, to reduce diffuse pollution from agricultural sources and consequently protect surface water resources. A particular aim is the attenuation of nutrients and pesticides. Based on the review of available information and preliminary tests within Aquisafe 1 (2007-2009), the second project phase Aquisafe 2 (2009-2012) is structured along the following main components: (i) Development and evaluation of GIS-based methods for the identification of diffuse pollution hotspots, as well as model-based tools for the simulation of nutrient reduction from mitigation zones (ii) Assessment of nutrient retention capacity of different types of mitigation zones in international case studies in the Ic watershed in France and the Upper White River watershed in the USA under natural conditions, such as variable flow. (iii) Identification of efficient mitigation zone designs for the retention of relevant pesticides in laboratory and technical scale experiments at UBA in Berlin. The present report provides a review of the properties and existing mitigation experience of the two herbicides Atrazine and Bentazone, which will be examined exemplarily in (iii). Whereas Atrazine is clearly the pesticide of greatest concern in the USA, Bentazone is mainly an issue in Europe with an increasing tendency. The sorption of Atrazine and Bentazone on soils is moderate. Moderate sorption in combination with medium to high persistency makes these compounds relatively mobile; therefore they can usually be observed in surface waters in general and in ground waters near places of their application. First experiences show that mitigation systems can be effective measures to decrease their concentrations by supporting biotic and abiotic dissipation processes, mainly at high residence times. Adding organic matter can improve adsorption of Atrazine and Bentazone, an important dissipation process in these systems. Degradation rates for Atrazine and for Bentazone can be increased by implementing highly microbiologically active conditions which can usually be accomplished in the presence of external carbon sources. While mineralization of both herbicides is favoured in aerobic -environments significant degradation of Atrazine was also observed under anaerobic conditions. A great number of open questions remain on how to design a mitigation system which is adequate to reduce herbicides in drainage water. For instance, there is no specific information on the degradation of diluted and adsorbed forms of the herbicides, very little information about necessary residence times, adsorption constants, half lives and leaching behaviour in specific substrates or comparable designs. Moreover, the influence of nitrogen, which is present in drainage water at high concentrations, on degradation of Atrazine and Bentazone remains uncertain. Finally, the behaviour of Atrazine and Bentazone (contained in agricultural drainage water) in mitigation systems in general and in bioretention swales in particular is poorly studied. Realistically, mitigation systems would only be implemented if they also allow significant reduction of nitrates. Given the existing knowledge, systems with both aerobic and anoxic zones are likely to bring most successful results regarding both herbicides and nitrates; though they may be difficult to implement. Both for nitrates and pesticides, the presence of external organic carbon sources (with a combination of fast accessible and sustainable substrate partitions) seems to be a good basis for dissipation processes and effective reduction.