The project assessed the potential environmental impacts of land application of Greenhouse nutrient feedwater (GNF) under the Ontario Nutrient Management Act as a best management practice (BMP) through field infiltration experiments established at four greenhouse operations representing a cross section of the vegetable greenhouse sector near Leamington, Ontario. The results demonstrated that the majority of the nutrients and other dissolved constituents in GNF applied at the highest permissible rates and practical loadings over a variety of soil types and agricultural land use practices remained within the vadose zone and at low concentrations over the course of the monitoring period. No evidence of significant environmental impact from the land application of GNF was observed. Overall, the results of the study suggest that land application of GNF in accordance with Ontario’s regulations is a feasible and environmentally reasonable treatment option for managing GNF.