The technologies for the depuration of oil-press waste waters (OPWW) available in Europe and Italy are expensive and not up to legal requirements. In Sardinia, pouring the waste water on agricultural soil is the only method currently utilised for their disposal.These waters are highly toxic and their treatment with traditional system causes serious environmental damage. The project develops an ecological solution to the OPWW problem consisting in a process which converts the waste into raw material, recyles all products and where the productive cycle and activities connected to it can be duplicated. The project proposer, the Consorzio Sa Corona Arrubia, has committed resources and made part of its land available to the project. The Provincia di Cagliari will provide important back up on result dissemination, while the Università di Cagliari has the necessary know-how to carry out the project. The project intended to demonstrate real-scale applicability of two depuration techniques. Biological: it uses the ability of the Pleurotus mushrooms to turn the OPWW organic load into non-toxic substances. Oxidative: the use of depurated water from the chemical-biological treatment (involving a selective oxidation of the organic load), as a substrate to grow micromycetes which, in turn, produce re-usable biomasses.

The project intended to tackle the long-standing problem of depuration of oil-press wastewater by means of ecologically sustainable methods. The project objectives were: •To provide an ecological solution for the depuration problem of oil press wastewater; •to develop a process where the waste toxic becomes raw material and all the obtained products can be used (Pleurotus mushrooms and clean water to be used for irrigation). Key actions: - Executive project of the depuration plant; - Construction and testing of the depuration plant; - Depuration activities (biological and oxidative); - Assessment of depuration activities (technical, scientific and financial); - Dissemination of activities and results. The expected results were the reduction in environmentally damaging wastewater disposal and generation of usuable products. It also expected to create jobs through the new process.

The project did not reach the objectives within the scheduled time since the purification plant to treat the OPWW (oil-press waste water)was still under construction at the end of the project. Consequently, the experimentation that would have validated the technique was not carried out. The cause was mainly due to an underestimation made by the beneficiary of the time needed to build the plant. Assessment of Results: The project did not reach its objectives by the official end date. However, the beneficiary and the partner were determined to continue and finish the work and it was finally completed successfully by the end of April 2002. The beneficiary also disseminated the final results in a workshop held on May 2002 Synthesis of results: 1.Environmental benefits: the environmental benefits of the project consist in a full re–use of the OPWW, avoiding the typical problems of this type of waste water, obtaining a mushroom production or producing depurated wastes that can be used as a substrate for micromycetes which, in turn, produce re–usable biomasses. The remaining water can be used for irrigation. Details on quantification of environmental benefits: Reduction of BOD (Biotic Oxygen Demand) and COD (Chemicla Oxygen Demand) by 90% (complying within European Water Directive and Italian law), with considerable reduction of polyphenoles (by 94%). Usable biomass: it constitutes about 20% of the original weight of waste waters to be treated. Quantity of OPWW per season: 3- 4.000 m3. Capacity of basins for the mushrooms cultivation: 175 litres. 2.Innovation, environmental cost/benefit ratio and Community interest: The objective of creating and applying new technologies to re–use the OPWW has almost been reached. However, due to the considerable delays in project implementation, it is difficult to properly evaluate the project as only 1 production cycle was completed. Nevertheless, the project's innovation potential is considerable, because the re – use of the OPWW is normally very difficult and adequate treatment processes have not been developed before. The technologies developed seem to be adequate, considering the area characteristics, but are limited by the fact that they have to be implemented in areas which display specific characteristics in terms of climate, geographical conditions, olive oil production and water resources. This means that the Community interest evaluation criterion would only seem applicable in areas with similar conditions. The cost/benefits ratio cannot be evaluated, at this time, as more production cycles seem to be necessary. 3. Reproduction potential and transferability: the project could be reproduced but, as stated above, it is particularly indicated for areas with specific environmental conditions. 4.Socio-economic effects: good socio-economic effects could result from the project. In fact, it has already resulted in some job creation in the area.