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More stringent environmental legislation and new or updated water management strategies have been adopted at both federal and local levels to address the growing problem of increasing demand on limited fresh water resources. Competition for access to available fresh water resources is increasing the pressure for sustainable water management practices that emphasize water reuse and recycle, with reduced fresh water withdrawals. In some jurisdictions targets for fresh water withdrawals have been set to zero, demanding innovative new technologies and applications of existing technologies to supplement natural fresh water sources. The serious need for new sources of potable water for human consumption has been widely recognized for some time, leading to a rapidly growing use of reverse osmosis (RO) for seawater desalination as well as significant advances in membrane technology itself. However, it is only in recent years that the implications of limited fresh water availability have begun to be seriously examined in other sectors. The usage of fresh water in the industrial sector has been immense, often leading to large volumes of contaminated waste water to be disposed of. In many instances the predominant contaminant is salt. Past practices in many industries have also left large volumes of salt contaminated surface and sub-surface soils at existing and/or abandoned industrial sites. Rain water or natural ground water flowing through these soils leaches out the salt, threatening fresh water resources. The growing recognition of the potential toxicity of the soil at these sites has led to increased requirements for environmental remediation prior to removing land from industrial usage. This, in turn, has led to increased volumes of salt contaminated waste water that must be disposed of, with a corresponding increase in the difficulty and cost of disposal. More economical, environmentally sound alternatives to current disposal methods must be found. Preliminary design calculations have been performed to establish a *Corresponding author. Presented at the EuroMed 2004 conference on Desalination Strategies in South Mediterranean Countries: Cooperation between Mediterranean Countries of Europe and the Southern Rim of the Mediterranean. Sponsored by the European Desalination Society and Office National de l’Eau Potable, Marrakech, Morocco, 30 May–2 June, 2004. 0011-9164/04/$– See front matter © 2004 Elsevier B.V. All rights reserved

Fig. 5. Data-logging station with flowmeters in background. The reverse osmosis environmental remediation pilot project is considered to have been a success. The objectives of the project were met and the data obtained provide the information required to establish system design requirements and operational characteristics with a high level of confidence. The key conclusions that can be drawn from the successful implementation and execution of the pilot project are as follows: • The CANDESAL advanced RO seawater desalination technology can be successfully extended to environmental remediation applications, such as treatment of salt-contaminated leachate from soil remediation. • The onsite conditions encountered provided a good appreciation for the extent of pretreatment that will be required to ensure reliable operation in the commercial production system.