The En-Z-Lite process makes it possible to efficiently remove organic contaminants from groundwater and respect legal limits.

The process is applied to treating refluent water and restoring a quality to the water that makes it suitable for industrial use, for example in the production of demineralised water, and therefore of steam. In 2007, further progress was made in developing the process with the registration of a patent for the thermal regeneration of water-repellent synthetic zeolites.

In the Taranto refinery a permeable reactive barrier has been installed for the on-site treatment of water by means of a reactive permeable material that degrades or immobilises the contaminating substances in underground water.

This pilot system is used for the on-site remediation of groundwater containing MTBE, hydrocarbons and AS.

In 2008, plans will be developed for a full-scale PRB and a financial evaluation of the project will also be carried out, while a number of sales outlets are currently offering full-scale equipment for the on-site treatment of groundwater. The En-Z-Lite process has shown itself to be the only treatment capable of respecting the rigorous MTBE levels required by authorities.

Water Reuse is the last step in a broader project named "The Integrated Water Project ", concerned with treating groundwater and reusing treated water for industrial purposes.

The aim of the Water Reuse project is to reuse all the water from effluent water treatment, including water from the hydraulic barriers contained in the "Definitive Remediation Project", to produce demineralised water for the production of steam, which is currently taken from refining wells.

The benefits include minimising the necessity of using well water and admitting much lower levels of volume and concentration into the receptor bodies.

At the end of 2006, a plant for treating groundwater was constructed at the refinery at Gela, allowing the depuration and total reuse of water that has been contaminated by hydrocarbons in the refinery's subsoil. Approximately 18,500 metres of pipe were laid, making this the biggest plant of its kind in Europe.

The treatment system is based on 67 inter-connected wells, which make it possible to automatically recover the water from all the area south of the industrial complex where underground bentonite resin barriers have been constructed to block the polluted groundwater from flowing into the sea.

The plant is designed to treat 300 cubic metres of liquid per hour. Once the water has been treated and distilled, part of it is then reused to fuel the boilers in the thermoelectric power station while another part is distributed throughout the area.

Re-injection of production water into the subsoil is a technology that allows the pressure in deposits to be maintained, while at the same time reducing the environmental impact of the dumping of production water from oil-related activities and reducing the amount of fresh water needed.

This type of operation is very important in sensitive areas such as the Libyan desert where there is a limited amount of water available.

In these areas Eni is committed to protecting water resources, using alternative solutions to replace the consumption of fresh water with sea water or brackish water, and numerous projects of this nature have been set up in Libya, Egypt (the Belaym field), Nigeria (the Ogbainbiri, Tebidaba and Ebocha fields) and Kazakhstan (the Kashagan field). There are two projects currently underway in Libya , in partnership with the National Oil corporation of Libya, which aim to reduce the amount of water used and to eliminate the environmental impact produced by the dumping of production water into the sea and into evaporation pits. The total investment in the two projects amounts to approximately €30 million.

The first project, in the Bouri offshore field, is based on re-injecting the production water that is currently dumped into the sea (operational from the second half of 2008), while the second project, in the Bu Attifel onshore field, consists of constructing a new system for treating production water with a capacity of around 100,000 barrels/day and modifying the present water injection system. These systems are designed to eliminate the dumping of production water and to progressively reduce the use of fresh water. In the El Feel field, also in Libya, there are plans to develop a system of extracting water from deep lying sources that is brackish and not directly usable for agricultural purposes or for drinking.

This operation will drastically reduce the use of fresh water.