Determinants of environmental assessment of Polish individual wastewater treatment plants in a life cycle perspective

The article presents results of an input-output data inventory and life cycle assessment (LCA) for individual wastewater treatment plants (IWWTPs), considering their whole life cycle, including the stage of construction, use and end-of-life. IWWTPs located in the area of a medium-sized town in Poland, were assessed from a systemic perspective. The research was conducted basing on actual data concerning performance of 304 individual wastewater treatment plants in Zory. Environmental assessment was conducted with ReCiPe and TRACI methods. Greenhouse gases (GHG) emission, eutrophication, fossil fuel and metal depletion were calculated. The LCA was conducted basing on ISO 14040 standard with SimaPro 8 software and Ecoinvent 3 database. The system boundary ranged from cradle to grave. It was shown that, at the construction stage, GHG emission depends on the amount of used cement, polyethylene, concrete, PVC and polypropylene. At the use stage, the GHG emission is determined by the sewage treatment technology and application of a bio-reactor in IWWTPs. At the construction stage, the fossil fuel depletion is determined by the amount of used polyethylene, PVC, cement, polypropylene and concrete; while the metal depletion is determined by the amount of used stainless steel, copper and cast iron. Data inventory and LCA of IWWTPs are presented for the first time. Conclusions of the work may support decisions taken by local governments concerning wastewater management in their area and promote and support solutions of high ecological standards.