Protected Horticulture and Environment. an Integral Decision Model for Greenhouse Waste Management in Southeastern Spain

Over 380000 tons of vegetable waste is produced annually in the “Campo de Dalías” zone (Almería, Spain), deriving from the diverse existing crops grown under plastic cover). Landfills containing this vegetable waste are a potential breeding ground for diseases and pests, they can also be the subject of uncontrolled burning, cause a riverbed blockage and, at the same time, they are an unsightly aspect of the landscape. The only way to prevent or minimize this problem is to adopt a comprehensive and environmentally sensitive waste management program. The utilization of the Contingent Valuation Method (CVM) has allowed the monetarization of the total environmental benefit of the projects undertaken, composting plant or in an energy recycling process, to the tune of 4082777 € and 4794566 €, respectively. Likewise, a Geographical Information System (GIS) has been used to locate an optimal zone for a composting plant. The solution obtained minimizes the transportation cost of organic waste. It represents 40% of the total cost at current market price. The subsequent integration of the results obtained with the previous methods in a costbenefit analysis showed when a decision on possible public action needed to be taken that the best option would be a composting project with a 63.58 million € Net Present Value (NPV), including the internalization in economic terms of the environmental benefit of recycling organic residue. If this benefit is not internalized, the project NPV would be negative.