[EN] Bio-waste is the biodegradable part of urban waste (UW). Actually, a lot of cities are collecting it together with the rest part, so a big quantity of bio-waste ends on landfills. The selective collection of this fraction makes easier its recycling. This brings a series of benefits as the reduction of biodegradable organic material on landfills, with the consequent reduction of greenhouse gases emissions (GHG), or the transformation of bio-waste into compost, what contribute to a minor use of chemical products on agriculture. This work is intended to modify the selective collecting system of urban waste of Castelló de la Plana in order to add the new dumpster for the distinction of that kind of residue. For that, first of all, the previous system is analysed and prepared to facilitate the next task. Then, basic guidelines are provided in order to establish the specific location for the dumpsters. All of that suppose, in some cases, the re-collocation of containers from the previous system. Finally, there is a business projection to estimate de costs of the implementation of the proposed system. TFGM