Emission levels for the design and operation of each project is established through the Environmental Impact Assessment (EIA) process.

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1 Guideline No.: EN/028 Issue Date: July Introduction Title: Environmental Guidelines for Dubai Metals and Commodities Centre (DMCC) Issued by: Environment Department DMCC would apply specific environmental guidelines for its projects on a case-by-case basis. With respect to DMCC types of industries the general environmental guidelines outlined here can be used, but, depending on the project, the requirements may need to be supplemented by additional requirements. DMCC clients are required to comply with its relevant, polices and guidelines, which emphasize pollution prevention, Reuse, Recovery, Recycle (RRR) options, waste minimization, including the use of cleaner production technologies. The intent of the guidelines is to minimize resource consumption, including energy use, and to eliminate or reduce pollutants at the source. For ease of monitoring, maximum permitted emissions limits are often expressed in concentration terms- for example, milligrams per liter (mg/i) for liquid effluents and, for air emissions, milligrams per normal cubic meter (mg/nm3), where normal is measured at one atmosphere and 25 Celsius. The focus, however, should continue to be on reducing the mass of pollutants emitted to the environment. Dilution of effluents and air emissions to achieve maximum permitted values is unacceptable. Occasionally, emissions limits are specified in mass of pollutants per unit of production or other process parameter. In such cases, the limits include leaks and fugitive emissions. Pollution control systems may be required in order to meet specified emissions limits. These systems must be well maintained and operated and must not be fitted with overflow or bypass devices unless such devices are required for emergencies or for safety purposes. The following sections contain requirements for air emissions, liquid effluents, hazardous wastes, and solid wastes. Sections on ambient noise and monitoring requirements are also included. The final section summarizes the key steps that will contribute to minimizing the impact of the project on the environment. 2.0 Emissions Guidelines Emission levels for the design and operation of each project is established through the Environmental Impact Assessment (EIA) process. The guidelines given below present acceptable emissions levels. All of the maximum levels should be achieved at all the time that the plant or unit is operating. 2.1 Air Emissions Most of the air emissions from subject types of industrial facilities originate with the fuel used for heating purposes or for generating steam for process purposes. Particular emissions that may originate in the process are addressed case by case. Concentration of contaminants emitted from the stacks of Page 1 of 11

2 significant sources including boilers, furnaces, etc., should not exceed the limits presented in EG No. 1 Air Environment Guidelines. The plant owner is required to demonstrate full compliance with the emissions limits specified. The following methods may be used to demonstrate compliance. For point sources compliance with the guidelines for particulate matter may be demonstrated by maintaining the stack emissions opacity below 250 mg/m 3 of Particulate Matter. The sulfur content of fuels may be used to demonstrate compliance with the sulfur dioxide (SO 2 ) emissions guidelines. The guidelines are met by the use of liquid fuels with sulfur content of 0.05% (500 ppm) or less. The client must maintain records of fuel analyses to demonstrate that the sulfur content of the fuel is at or below the specified levels. Manufacturers performance guarantees can be used to demonstrate that the emissions guidelines for sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ) are met. The performance guarantees must be verified by conducting an initial performance test after the equipment has been commissioned. The sponsor must maintain record to demonstrate that the equipment is operated within manufacturers specifications. Alternatively, stack emissions can be monitored for specified contaminants. The monitoring must be sufficiently frequent to demonstrate continued compliance with the guidelines. To ensure that ambient air conditions are not compromised, concentration of contaminants measured immediately outside the project property boundary should not exceed the limits presented in Guideline No.: EI/028 Air Environment Guidelines. 2.2 Liquid Effluents Proper treatment facilities for process wastewater and domestic sewage should be provided or the same to be disposed to Dubai Municipality (DM) facility. Please refer to Annex 28.1 for DM Standards applicable to pre-treated wastewater disposal at their central wastewater treatment plant and re-use in irrigation. 2.3 Hazardous Materials and Wastes DMCC clients shall, whenever possible, use non-hazardous instead of hazardous materials. All hazardous wastes, process residues, solvents, oils, and sludge s must be properly disposed of to DM. The following management measures for handling hazardous wastes and materials should be implemented: a. All hazardous (ignitable, reactive, flammable, radioactive, corrosive and toxic) materials must be stored in clearly labeled containers or vessels. Page 2 of 11

3 b. Storage and handling of hazardous materials must be in accordance with local regulation or international standards and appropriate to their hazard characteristics. Storage and liquid impoundment areas for fuels, raw and in process materials solvents, wastes and finished products should be designed with secondary containment (e.g. dikes and berms) to prevent spills and the contamination of soil, groundwater, etc. c. Fire prevention systems and secondary containment should be provided for storage facilities, where necessary or required by regulations, to prevent fires or the release of hazardous materials to the environment. d. Formulations containing chromates should not be used in water treatment processes. e. Transformers or equipment containing polychlorinated biphenyls (PCBs) or PCB-contaminated oil should not be installed. Existing equipment containing PCBs or PCB-contaminated oil should be phased out and disposed of in a manner consistent with the relevant requirements. f. Several chemicals classified as ozone depleting substances (ODSs) are scheduled for phase out under Montreal Protocol on Substances That Deplete the Ozone Layer. They include chlorofluorocarbons (CFCs); halons;1,1,1-trichloroehtane (methyl chloroform) ; carbon tetrachloride; hydrochlorofluorocarbons (HCFCs); hydrobromofluorocarbons (HBFCs); and methyl bromide.these chemicals are currently used in a variety of applications, including domestic, commercial, and process refrigeration (CFCs and HCFCs); domestic, commercial, and motor vehicle air conditioning (CFCs and HCFCs);manufacturing of foam products (CFCs); solvent cleaning applications (CFCs, HCFs, methyl chloroform, and carbon tetrachloride); aerosol propellants (CFCs) fire protection systems (halons and HBFCs); and crop fumigants (methyl bromide). No systems or processes are to be installed using CFCs, halons, 1,1,1-trichloroehtane, carbon tetrachloride, methyl bromide, or HBFCs. HCFCs should be considered only as interim or bridging alternatives, since they too are to be phased out. 3.0 Solid Wastes DMCC companies are to implement the following practices for managing solid wastes generated in the course of operating the facility: a. Recycle or reclaim materials where possible. b. If recycling or reclamation is not practical, wastes must be disposed of in an environmentally acceptable manner and in compliance with DM regulations. 4.0 Other Environmental Requirements 4.1 Ambient Noise Noise abatement measures should comply with maximum allowable noise level of 70 db at the fence line of plant. Page 3 of 11

4 4.2 Monitoring and Reporting DMCC companies are required to maintain record of air emissions, effluents, and hazardous wastes sent off site, as well as significant environmental events such as spills etc that may have an impact on the environment. The information should be reviewed and evaluated to improve the effectiveness of the environmental protection plan. 4.3 Air Environment This section establishes reporting, testing, monitoring and analyses requirements for sources of air pollution located or proposing to locate in DMCC. The purpose of these requirements is to assess compliance with the ambient air quality criteria and air emission limitations. Prior to commencing construction or modification, all sources of air pollution not specifically exempted must prepare and submit an EIA report and include a section pertaining to the air environment. Depending on the nature and size of the source, Authority may require the applicant to prepare an ambient air quality analysis and/or provide ambient air monitoring data. After start-up, large emission sources and potentially hazardous or nuisance-type sources are required to conduct source emission (performance testing) and report the results to Authority for compliance evaluation. For certain specified emission sources, continuous air emission monitoring and quarterly reporting is required on a case by case basis. At any time, after start-up, request can be made for any industrial facility to prepare an updated air emissions inventory or provide other information relating to the source in question. Air Emissions Performance Testing a. Performance tests are required on a case-by-case basis, for any source that may be hazardous to the environment or may be an odor nuisance. The aim of performance testing is to verify a pollutant s emission concentrations or rate at a point source and to ensure that there is no violation of the industrial source emission criteria and/or ambient air quality (at fence-line) criteria or any emission limit used for compliance evaluation. It should be noted that as a general industry requirement stack testing ports and work platforms should be installed at all facilities, which have a potential to release pollutant quantities or are otherwise subject to the criteria stated above. b. Performance tests shall be done at earliest after normal operation. These tests shall be conducted by an independent consultant. The date, time and place of any performance test shall be given to Authority at least one week in advance so they may witness such tests. c. Performance tests shall consist of the determination of exhaust gas temperatures and volumetric flow rates and gas analyses for the pollutants and efficiency of abatement equipment for which the test is required. The tests shall be conducted according to the accepted international reference test methods. d. Each performance test shall consist of a minimum of three separate sampling runs conducted within a 48- hour period. Each run shall be obtained while the source is operating at normal load. Page 4 of 11

5 The arithmetic mean of the results of the three runs shall be used for the purpose of determining compliance with applicable emission limitations. e. The results of the performance tests shall be submitted within one month of their completion. If procedures and/or methodologies used for any tests were inappropriate or defective, a retest may be required. 4.4 Water Environment This section establishes reporting, testing, monitoring and analyses requirements for sources of water pollution located or proposing to locate at DMCC. The purpose of these requirements is to assess compliance with the DM wastewater discharge criteria. At least six (6) months prior to commencing construction of any industrial or other wastewaterproducing facility, or adding to or modifying an existing facility, an Environmental Impact Assessment (EIA) report, containing a water environment details as per Authority EIA Guidelines shall be submitted by the industry or facility to Authority. After start-up, the facility owner/operator may be required to sample/analyze effluents initially and/or periodically to demonstrate compliance with the discharge criteria specified earlier. For groundwater appropriate number of boreholes will be installed for quarterly monitoring and reporting. For some effluent parameters, a continuous monitoring and monthly qualityreporting is required on a case-by-case basis. 4.5 RRR Options, Cleaner Production and Waste Minimization All DMCC companies should adopt reuse, recovery or recycling (RRR) options for wastewater generated. It is emphasized to minimize the generation of wastewater and adopt cleaner production practices. 4.6 Noise Environment Performance Testing In line with DMCC requirements (see Annex 28.2) for premises a noise performance testing, at the boundary fence line, would be conducted within one month upon normal operation. On a case-by-case basis or annual noise level testing and reporting is required. 4.7 Solid / Hazardous Waste All solid/hazardous waste generated in DMCC companies is to be disposed off as per DM guidelines. RRR options (see above Section) and wastes minimization must be adopted by all DMCC companies. 5.0 Key Issues for Environment Control The key production and control practices that will assist in meeting emissions requirements can be summarized as follows: a. Where feasible, choose RRR options, cleaner production, integrated pollution control, waste minimization, energy-efficient and environmentally sound processes. Page 5 of 11

6 b. Ensure that control, treatment, and monitoring facilities are properly maintained and that they are operated according to their instruction manuals. 6.0 Case Study: Specific Environmental Requirements for Gold / Diamond Refineries and Workshops 6.1 EIA Study Gold and Diamond finishing is often a pollution intensive industry, with significant emissions of both metals and organic process chemicals. It is a major contributor of toxic inputs to water treatment plant, landfill and atmosphere. Due to potential serious environmental impacts a proper EIA study should be required. 6.2 Pollution Pathways Gold finishing is the application of physical, chemical or electrochemical processes to a work piece to alter its surface properties or appearance. Chemical (degreasing, cleaning, pickling, etching, coating and electrochemical electro-plating, polishing, cleaning and anodizing) processes are the main waste producers. Both types of processes on a work piece are usually performed in baths with chemicals and other compounds, followed by rinsing operations. Process chemicals and compounds which are carried from baths to the water (drag-out) and accumulate in the rinse. a. Rinsing operation waste and drag out pollution Gold rinsing generates wastewater, which constitutes the metal finishing industry s chief overall source of waste. Drag-out in rinse wastewater is responsible for the majority of process chemicals lost in metal finishing and can contain toxic compounds such as cyanides. Other potential hazards in wastewater can include: nitric, sulfuric, hydrochloric and hydrofluoric acids, cyanides and oil and grease. Failure to incorporate efficient drainage techniques and equipment while rinsing adds up to 70% more drag out waste than is otherwise necessary. Operations lacking the technological means to reuse rinse water and to recover metals and metals salts from rinse water and spent process baths can also contribute to extra water use and toxic effluent. Open loop systems discharge more waste than do closed loop designs. Excess water consumption and drag out generation increase the volume of wastewater requiring treatment. This produces great amounts of sludge, a solid waste which can contain toxic metals. To conserve rinse water, reduce drag-out, reuse rinse water, and recover metals. b. Bath solution replacement The replacement of spent or contaminated baths (plating, cleaning, etc.) can yield much waste which typically is taken off line and treated or put in containers for off-site disposal. This waste contains many of the same toxic compounds found in rinse water, acids, metals, and cyanides. Facilities without methods to extend bath life augment the quantities of such compounds discharged into the waste stream. Page 6 of 11

7 c. Toxic air emissions Many gold finishing operations generate air emissions, including mists, from plating baths and vapors from cleaning and degreasing processes, which use solvents. These toxic emissions can threaten the safe of the workplace and labors and surrounding area. Operations, which neither provides equipment to prevent the escape of air pollutants nor substitute less hazardous alternatives where feasible, enhance the danger to workers, their neighbors, and the environment. d. Hazardous Process Compounds There are a number of metal finishing process compounds, which present particular health and pollution problems e.g. cyanide-based solutions. For many applications of these materials substitutes exists. Failure to implement viable alternatives perpetuates the unnecessary discharge or escape of highly toxic compounds into the environment. e. Cyanide-based solution Various cyanides are used in gold electroplating baths. Plating generates significant amounts of cyanide waste, much of it in wastewater from associated rinsing operations. Discharge of this waste risks production of especially toxic hydrogen cyanide gas (HCN) from the mixture of cyanide waste with other effluent containing acids. Cyanide in solutions is extremely dangerous. A potentially more serious problem for electroplaters is the accidental addition of an acid to a plating bath with cyanide, which can create HCN. HCN enters the human body by inhalation, ingestion, or skin absorption. 6.3 Environmental Impacts a. The environmental effects of the gold finishing industry are potentially severe and wide-ranging. Some toxic compounds used in metal degrade quickly; others are persistent and can impact the environment far from the point of discharge. Many metals tend to accumulate in sediment and plant and animal and human beings. b. Residues or spills which taint soil around industry facilities may lead to surface and ground water pollution. Disposal of wastewater containing hazardous materials can contaminate streams. Proper wastewater treatment facility is required. c. Corrosive acids presence in wastewater would potentially attack sewers structures proper acid resistant materials/floor used. d. Good housekeeping, proper ventilation/exhaust systems be installed. Baths (acids) must be provided with hoods, which should be connected to scrubbers before venting to the environment. Planned multi story building will only make it more acute. e. Segregated industrial and domestic wastes should be planned. Page 7 of 11

8 f. Potential sludge/waste filters should be disposed off as a hazardous waste. g. Acidic and cyanide bearing wastewater should ideally be segregated for treatment. All wastewater streams should be treated to meet DM acceptable limits (see Annex 28.1) for disposal or reuse in irrigation. 6.4 Alternatives a. Technologies and Processes Rinse water can be recycled in an open- loop or closed- loop system. The former allows treated effluent to be reused in rinsing, but the final rinse is fed by fresh water; effluent thus continues to be discharged. In a closed loop design, the treated effluent is returned to the rinse system. According to the U.S. EPA This system can significantly reduce water use and the volume of water discharged to the waste water treatment plant. Closed- loop systems also facilitate recovery processes to reclaim metals from the plating operations. Rinse water efficiency techniques can improve the economic viability of either system. Ways to improve rinse efficiency and conserve water include: agitation of rinse water, by air and hydraulic, mechanical, or ultrasonic methods; agitation of work pieces during rinsing; and use of spray rinsing techniques (which require between one-eight and one-fourth the water that dip rinses use), alone or in combination with immersion. In addition, equipment to permit the reuse of rinse water for one operation as feed for another (reactive rinsing) can reduce rinse water consumption by 50%. Established metals recovery and process bath regeneration technologies are: filtration and centrifugation; evaporation; electrolytic recovery; reverse osmosis; ion exchange; and electrodialysis (the most effective method will depend on a variety of factors, e.g. size of facility or type of baths or effluent) Process bath life can be extended by: filtration; electrolytic dummying; precipitation ; and various improved housekeeping measures. Air emission controls include: exhaust hoods with air filters; mist eliminators; and fume scrubbers. Process baths, which generate mists, should be designed to reduce the amount of mist reaching the ventilation system (i.e. with more freeboard) In addition, there are process changes, which can eliminate the need for solvents or for cleaning altogether. These are: ultrasonic cleaning; automated aqueous cleaning; aqueous power washing: no-clean flux (low solids fluxes); no-clean soldering (inert atmosphere); and vacuum furnaces. b. Cyanide According to UNEP/IEO alternatives to cyanide is non-cyanide copper plating baths available commercially. Cyanide free alkaline phosphonate copper plating technology is one possibility; pyrophosphate based solutions (which have been the most readily available replacements for cyanide plating baths) are another. Recent industry literature also describes non- cyanide sulfite gold plating and gold electroplating solutions. Page 8 of 11

9 Annex 28.1 Dubai Municipality (DM) Standards for Discharge / Re-use of Wastewater Physico Chemical Maximum Allowable Limits for Discharge to Parameters Units Sewerage Land as for Irrigation System Drip Spray Biochemical Oxygen Demand mg / l 1, Chemical Oxygen Demand mg / l 3, Chlorides mg / l mg / l Not less than 0.5 mg/l after 30 Chlorine residual 10 minutes contact time Cyanides as CN mg / l Detergents mg / l Fluorides mg / l Ammoniacal Nitrogen mg / l Organic (Kjeldahl) Nitrogen mg / l 10 5 Total Nitrogen mg / l Oil and Grease emulsified mg / l Oil and Grease free oil mg / l ph (range) units Pesticides, non-chlorinated mg / l Phenols mg / l Phosphorus mg / l Sulfates, total mg / l Sulfides as S mg / l Suspended Solids mg / l Temperature mg / l 45 or > 5 of ambient - - Total Dissolved Solids (TDS) mg / l 3,000 1,500 1,000 Page 9 of 11

10 Metals Total Metals mg / l Aluminum (Al) mg / l Arsenic (As) mg / l Barium (Ba) mg / l Beryllium (Be) mg / l Boron (B) mg / l Cadmium (Cd) mg / l Chromium (Cr) mg / l Cobalt mg / l Copper (Cu) mg / l Iron (Fe) mg / l Lead (Pb) mg / l Magnesium (Mg) mg / l Manganese (Mn) mg / l Mercury (Hg) mg / l Molybdenum (Mo) mg / l Nickel (Ni) mg / l Selenium (Se) mg / l Silver (Ag) mg / l Sodium (Na) mg / l Zinc (Zn) mg / l Bacteriological Fecal Coliforms MPN / 100 ml Page 10 of 11

11 Annex 28.2 Noise Allowable Limits in Different Areas Area Allowable Limits for Noise Level (db)* Day Night (7 a.m. 8 p.m.) (8 p.m. 7 a.m.) Residential Area With Light Traffic Residential Areas In The Downtown Residential Areas Which Include Some Workshops & Commercial Business or Residential Areas Near The Highways Commercial Areas & Downtown Industrial Areas (Heavy Industry) * Exposure time for certain level of noise (hour) Page 11 of 11