The BIOMIM'HUMIQUE project proposes to combine the natural chelating properties of humic substances (HS) extracted from waste composts (promoting the precepts of a circular economy) with those of biomimetic catalysts in order to develop a new, eco-responsible and sustainable way of remediation of contaminated soils and effluents.Different types of composts will be characterized from a geochemical point of view using a "humeomic" methodology with the help of nuclear magnetic resonance (NMR) of carbon (13C) and proton (1H) in 1 and 2 dimensions as well as high resolution mass spectrometry (ESI and APPI-Orbitrap-MS and FTICR-MS) and gas chromatography coupled to high resolution mass spectrometry (GC-QTOF MS), in order to determine the molecular nature of humic substances extracted from the different types of composts. The washing of the contaminated soils will be done in two steps. The first step will consist of washing metals and/or organic pollutants with the HS. The second step will consist in a catalytic copolymerization of the residual contaminants in the humic superstructures. This second step will therefore involve a biomimetic catalyst. The chosen biomimetic catalyst is a synthetic water soluble metal porphyrin that can be used either with an oxidant (H2O2) or under solar irradiation.