Peñoles was founded in 1887.

“EXPERIENCES OF WASTEWATER AND WATER REUSE AT PEÑOLES INDUSTRIES: THE CASES OF MET – MEX AND FRANCISCO I. MADERO”

What is Peñoles? • Peñoles was founded in 1887. • Peñoles is a mining group with integrated operations in smelting and refining of non-ferrous metals, and producing inorganic chemicals. • Peñoles is the world largest producer of refined silver, metallic bismuth and sodium sulfate, the leading Latin American producer of refined lead and zinc, and Mexico’s largest refined gold producer.

MISSION To add value to non-renewable natural resources in a sustainable manner. Shareholders Personnel Customers Adding value in a sustainable manner Community Suppliers

Met – Mex is a metallurgical complex located in Torreón, Coahuila and Francisco I. Madero Mining Unitis a Zinc ConcentratingPlant, near Zacatecas, City. MET - MEX FCO. I. MADERO

PROPOSED HYDROLOGICAL BALANCE Increasing water availability through environmental infrastructure for reuse and distribution Reducing water extractions through an efficient usage NATURAL AVAILABILITY EXTRACTIONS

WHAT DOES WATER CULTURE MEAN? • Customs, values, attitudes and habits a person or a society has regarding water importance. • Availability of water resources in the environment and the required actions to get, distribute, clean and reuse it. • This culture implies compromise to appraise and preserve it, using it with social and environmental responsibility.

WHY SHOULD WE TREAT RESIDUAL WATER? • To help the balance between the Earth and the Hydrosphere. There is only a certain capacity to receive, absorb and transform different kinds of wastes into nutrients. • If we exceed this carrying capacity, wastes will accumulate given origin to water contamination. • When the extraction is greater than recharge, water will become scarce.

Prices per cubic meter according to Availability Zones established on the Mexican Federal Law on Water Rights (Article 223) Availability zone pesos/ m3 I 14.3343 II14.630 III 9.5557 IV 7.8837 V 6.2111 VI 5.6135 VII 4.2252 VIII 1.5012 IX 1.1250

In Met-Mex Peñoles, Gold, Silver, Lead, Zinc and Bismuth, are refined from ores and concentrates and these processes consume water. • The City of Torreon, Coahuila, belongs to Availability Zone II, whose right to make use of water is 14.63 Pesos / cubic meter. • Water consumption at our facilities is: 12,000 m3 /day (139 LPS)

GENERAL SCHEME FOR WATER MANAGEMENT AT MET - MEX Evaporation Raw Sewage from the city Water in products TREATMENT PLANT PROCESSES Residual Water TREATMENT BatteryLimit GREEN AREAS Well water GENERALSERVICES

WASTEWATER GENERATION, TREATMENT AND REUSE BOILER FEED WATER PRODUCTION PLANT AND OFFICE INTERNAL DRAINAGE REVERSE OSMOSIS ZINC PLANT NANO- FILTRATION NEUTRALIZATION SLAG GRANULATION EVAPORATION PURGE WASTE WATER TREATMENT PLANTS COOLING TOWERS LEAD ACID PLANT ZINC ACID PLANT REPLACING WATER LEAD SMELTER AND REFINERY SEWAGE CITY WATER GREEN AREAS

WASTE WATER TREATMENT PROCESS GARBAGE SCREEN ROTATING DRUM FILTER RAW SEWAGE SETTLING TANK AIR EXTENDED AERATION REACTOR SLUDGE DIGESTER ACTIVATOR SEDIMENTATION TANK DIGESTED SLUDGE TO COMPOSTE PRESS FILTER UV DESINFECTION WATER TO PROCESSES AND REVERSE OSMOSIS ANTHRACITE AND CARBON FILTERS

MULTISTAGE WASTEWATER TREATMENT PROCESS AT MET - MEX AFTER REVERSE OSMOSIS AFTER IONIC EXCHANGE TREATED WATER WASTE WATER BOD 330 <5 0 0 TSS 40 15 0.5 0.3 TDS 1,300 1,300 80 5 pH 7.0 7.0 6.0 9.0 HARDNESS 400 400 10 <1.0 Ca +2 120 120 3 <1.0 PO4 20 15 2 0 Cl 120 110 15 <1.0 Mg 30 30 <1.0 <0.02 SiO2 30 30 5 <1.0 Conductivity 1,600 1,450 60 <0.25 μ mohos

SUMMARY OF WATER CONSUMPTION AND SAVINGS AT MET-MEX PEÑOLES TOTAL DAILY CONSUMPTION 12,000 m3 WATER RIGHTS 13,500 USD / day COST OF TREATMENT 0.20 USD / m3 NOT USED WELL WATER 11,300 m3 /day APPROXIMATE SAVINGS = 3.8 MILLION DOLLARS / YEAR INVESTMENT FOR A 130 LPS PLANT = 4 MILLION USD

FRANCISCO I. MADERO MINE WASTE WATER TREATMENT FACILITIES

MULTISTAGE WASTEWATER BIOLOGICAL TREATMENT PROCESS BIOLAK WOX SYSTEM Sedimentation Tank Sand Filter Raw sewage from Zacatecas City Sand Trap To Industrial Processes 8 8 Automated Screen Flocculation & Quick Mix Chlorine Disinfection Aeration Tank Q = 60 L / s Piping length = 17.4 km Digested Sludge to promote revegetation on tailings dam

MEAN CONCENTRATIONS OF WATER QUALITY PARAMETERS AT FRANCISCO I. MADERO MINING UNIT WASTE WATER TREATED WATER PARAMETERS BOD 100 mg / l 15 mg / l 4 mg / l TSS 42 mg / l 1,100 mg / l TDS 1,100 mg / l 6.8 7 pH

VIEWS OF THE WASTEWATER FACILITY AT MET-MEX PEÑOLES AND FRANCISCO I. MADERO FRANCISCO I. MADERO AERATION AND SEDIMENTATION TANK MET-MEX PEÑOLES AERATION REACTORS

Treating and reusing water gives benefits such as: Less contamination of rivers, lakes, lagoons and consequently, ground water. Reduces costs for production facilities. Treating and reusing water, changes customs, behaviors, values and habits of people towards water. Education is vital to create water awareness among the population helping preserve rivers, lakes, wetlands and ground water. Treating and reusing water add value to non renovable resources and lead us to towards a sustainable development. CONCLUSIONS

Peñoles was founded in 1887.