We are searching for alternatives to limestone for pH-control in bioleaching processes. Acid leaching of ash in combination with bacteriological oxidation of mineral sulfides recycles metal contaminants. Sulfuric acid from bioleaching is one alternative in areas rich in mineral sulfides. De-ashing of coal and coal-ash after treatment become attractive when new regulations for depositories are implemented. The treated ash is deposited with the mining residues rather than at designated sites. Wood-ash has superior neutralizing capacity and no toxic elements but forested areas in Europe contain Cs-137 and Ra-226 from the Chernobyl fallout. We observed this for Pinus Sylvestris from central Sweden and Carpinus Betulus from NE Turkey and for short-rotation plants at phosphate sites worldwide. Three Turkish coal-ashes, containing U-238, Th-232 and Cs-137, and two wood-ashes, containing Cs-137 and Ra-226, were leached in sulfuric acid (initial S/L ratio 1:10, 25oC, pH 1.0). Extracted Cd, Co, Cu, Ni and Zn are readily recovered in the down-stream processes of the bioleaching plant, but U, Th, V and Mn require additional steps. Gamma-spectra were measured of the dried residues as a function of leaching time. This revealed constant total activity for the solid plus liquid phases of wood-ashes during leaching. Akin activities of the leachate during coal-ash treatment were calculated from ICP data. U was dissolved to 60 % in 30 min. Th and Cs recoveries from coal-ash varied with mineral content. Cs recovery from wood-ash is hampered by high combustion temperature and formation of complex oxides.