As a consequence of the implementation of Directive 2009/28/EC on the promotion of the use of energy from renewable sources, the number of biomass plant facilities continues to grow in Croatia, and their by-product (waste) biomass ash (bioash) needs to be stored adequately. Based on our recent studies it is assumed that due to its specific physicochemical properties (pH >12.5; huge active/adsorption interface; significant content of P, K, Ca, Mg) bioash could have a range of positive impacts in amelioration of metal-contaminated soils. Metal contamination of arable land is a rising anthropogenic degradation that causes negative economic and ecological consequences in food production. The main objectives of the project are: 1) to characterize physicochemical properties of bioashes from several biomass plants, and to determine the effects of different bioash levels on 2) chemical and 3) microbial changes in metal-contaminated soils, 4) vegetative parameters and mineral content of agricultural test crops grown in such contaminated soils. The Faculty has all the infrastructure and most laboratory resources needed, accredited with modern instruments (ICP-OES, HPLC, SFA) for the successful accomplishment of all planned activities, with some advanced microscopy and mineralogy analyses (SEM-EDS, SIMS, XPS, XRD) which will be done in external labs. This project will contribute to postdoc. researcher competencies, educate PhD/Masters graduates, and will enhance international recognition of the research work by delivering project website, workshops/round tables and scientific meetings, and by disseminating the project results at conferences and publishing at least 5 papers in Q1/Q2 journals. Finally, the project is expected to provide novel and more sustainable solutions for managing bioash materials and metal-contaminated soils, which represent an increasing environmental issue at national, European and global levels.