DECOSET is a joint construction syndicate, composed exclusively of public establishments of inter-municipal cooperation (EPCI), created in 1993 with the aim of setting up an optimal sector for the treatment and recovery of household waste. DECOSET brings together 8 EPCI (who exercise their collecting competence and who have transferred to DECOSET the treatment competence) which total 152 municipalities and a population of 1,054,402 inhabitants (population 2024). Household and similar waste is collected by EPCI members of Decoset. They are then given to him so that Decoset can value or eliminate them. This waste can be household waste or occasional waste such as green waste, used furniture, end-of-life household appliances, etc. The project presented is based on the conclusions of the territorial planning study of sorting, carried out in 2019 by the INDDIGO design office, and monitored by ADEME, the Region and CITEO. The choice chosen is to maintain the current organisation of separate collection and the construction of a new single sorting centre, on the Bessières site, close to the current sorting centre.