Environmental, Health, and Safety (EHS) Guidelines GENERAL EHS GUIDELINES: ENVIRONMENTAL WATER CONSERVATION APRIL 30, 2007 33 WORLD BANK GROUP 1.4 Water Conservation Applicability and Approach .............................................33 Water Monitoring and Management................................33 Process Water Reuse and Recycling..............................33 Building Facility Operations ............................................34 Cooling Systems............................................................34 Heating Systems............................................................34 Applicability and Approach Water conservation programs should be implemented commensurate with the magnitude and cost of water use. These programs should promote the continuous reduction in water consumption and achieve savings in the water pumping, treatment and disposal costs. Water conservation measures may include water monitoring/management techniques process and cooling/heating water recycling, reuse, and other techniques and sanitary water conservation techniques. General recommendations include: ��� Storm/Rainwater harvesting and use ��� Zero discharge design/Use of treated waste water to be included in project design processes ��� Use of localized recirculation systems in plant/facility/shops (as opposed to centralized recirculation system), with provision only for makeup water ��� Use of dry process technologies e.g. dry quenching ��� Process water system pressure management ��� Project design to have measures for adequate water collection, spill control and leakage control system Water Monitoring and Management The essential elements of a water management program involve: ��� Identification, regular measurement, and recording of principal flows within a facility ��� Definition and regular review of performance targets, which are adjusted to account for changes in major factors affecting water use (e.g. industrial production rate) ��� Regular comparison of water flows with performance targets to identify where action should be taken to reduce water use. Water measurement (metering) should emphasize areas of greatest water use. Based on review of metering data, ���unaccounted��� use���indicating major leaks at industrial facilities��� could be identified. Process Water Reuse and Recycling Opportunities for water savings in industrial processes are highly industry-specific. However, the following techniques have all been used successfully, and should be considered in conjunction with the development of the metering system described above. ��� Washing Machines: Many washing machines use large quantities of hot water. Use can increase as nozzles become enlarged due to repeated cleaning and /or wear. Monitor machine water use, compare with specification, and replace nozzles when water and heat use reaches levels warranting such work. ��� Water reuse: Common water reuse applications include countercurrent rinsing, for example in multi-stage washing

Environmental, Health, and Safety (EHS) Guidelines GENERAL EHS GUIDELINES: ENVIRONMENTAL WATER CONSERVATION APRIL 30, 2007 34 WORLD BANK GROUP and rinsing processes, or reusing waste water from one process for another with less exacting water requirements. For example, using bleaching rinse water for textile washing, or bottle-washer rinse water for bottle crate washing, or even washing the floor. More sophisticated reuse projects requiring treatment of water before reuse are also sometimes practical. ��� Water jets/sprays: If processes use water jets or sprays (e.g. to keep conveyors clean or to cool product) review the accuracy of the spray pattern to prevent unnecessary water loss. ��� Flow control optimization: Industrial processes sometimes require the use of tanks, which are refilled to control losses. It is often possible to reduce the rate of water supply to such tanks, and sometimes to reduce tank levels to reduce spillage. If the process uses water cooling sprays, it may be possible to reduce flow while maintaining cooling performance. Testing can determine the optimum balance. o If hoses are used in cleaning, use flow controls to restrict wasteful water flow o Consider the use of high pressure, low volume cleaning systems rather than using large volumes of water sprayed from hosepipes o Using flow timers and limit switches to control water use o Using ���clean-up��� practices rather than hosing down Building Facility Operations Consumption of building and sanitary water is typically less than that used in industrial processes. However, savings can readily be identified, as outlined below: ��� Compare daily water use per employee to existing benchmarks taking into consideration the primary use at the facility, whether sanitary or including other activities such as showering or catering ��� Regularly maintain plumbing, and identify and repair leaks ��� Shut off water to unused areas ��� Install self-closing taps, automatic shut-off valves, spray nozzles, pressure reducing valves, and water conserving fixtures (e.g. low flow shower heads, faucets, toilets, urinals and spring loaded or sensored faucets) ��� Operate dishwashers and laundries on full loads, and only when needed ��� Install water-saving equipment in lavatories, such as low- flow toilets Cooling Systems Water conservation opportunities in cooling systems include: ��� Use of closed circuit cooling systems with cooling towers rather than once-through cooling systems ��� Limiting condenser or cooling tower blowdown to the minimum required to prevent unacceptable accumulation of dissolved solids ��� Use of air cooling rather than evaporative cooling, although this may increase electricity use in the cooling system ��� Use of treated waste water for cooling towers ��� Reusing/recycling cooling tower blowdown Heating Systems Heating systems based on the circulation of low or medium pressure hot water (which do not consume water) should be closed. If they do consume water, regular maintenance should be conducted to check for leaks. However, large quantities of water may be used by steam systems, and this can be reduced by the following measures: