The water produced at the Amal oil field in Libya is directly stored for evaporation in in-ground-pits. As there are a large number of oil production wells, there is a risk of environmental pollution because of the waste water’s eventual penetration into subsoil and surface waterways. From a technical point of view, the existing system of reservoir water disposal into storage pits will not be adequate to meet the increasing water production. Besides, the discharge of produced water without previous treatment is ecologically unacceptable. In this paper, a modern concept of produced water preparation is proposed, and the method of its disposal defined, applying an integrated approach to solving this problem, including technological, economic and environmental aspects. Produced water preparation in an oil field in Libya was chosen for the proposed implementation of an option with the lowest operating costs (storage tanks and liquid hydrophobic filter tank).