2006  MEADOWBANK GOLD PROJECT Cumberland Resources Ltd. AIR QUALITY EIS

2006  Identify activities potentially impacting air quality  Define type of air contaminants  Calculate emissions and find their locatons  Predict ground-level concentrations  Compare predicted concentrations to AAQO MEADOWBANK GOLD PROJECT Scope Air Quality Overview

2006 Point Emission Sources  Power plant MW maximum power demand -three diesel generators plus one stand-by -atmospheric dispersion maintained by 30.5 m stacks  Primary crusher and mills

2006 Mobile Emission Sources  Most of mobile sources will be trucks  Ore payload 90 tonnes, empty truck 60 tonnes  Maximum haul distance 7.5 km one way  Diesel supply for mobile equipment 11,200 m 3 /a

2006 Fugitive Emission Sources  Tailings  Coarse-ore stockpile – 17 m high 44 m base diameter  Conveyors  Drilling and blasting

2006 Air Pollutants  Sulphur oxides (SO 2 and SO 3 ) – sources: -diesel engines (power plant, trucks, loaders, tractors)  Nitrogen oxides (NO and NO 2 ) – sources: -as above  Particulate matter (TSP, PM 10, PM 2.5 ) – sources: - diesel engines, wheel entrainment, fugitive  Other contaminants: -carbon monoxide and carbon dioxide -unburned hydrocarbons

2006 Dispersion Modelling  Dispersion modelling predicts ambient ground-level concentration of air pollutants  Model inputs: -emissions data (rate, location, source parameters) -meteorology, buildings, receptors data  Models outputs: -concentration isopleths -PM precipitation isopleths

2006 Summary of Dispersion Modelling Results SubstanceSourcesAverage Time Max GLC μg/m 3 AAQS μg/m 3 Sulphur dioxide (SO 2 )Plant & Vehicles 1 h 24 h Annual Nitrogen oxides (as NO 2 )Plant & Vehicles 1 h 24 h Annual Carbon monoxide (CO)Plant & Vehicles 1 h 8 h ,000 15,000 Particulate matter <10 μm dia. (PM 10 )Plant 24 h Annual

2006 Monitoring Monitoring of the concentration of suspended particulate matter in the air surrounding the major areas of activity (dynamic monitoring) with Partisol air samplers.

2006 Monitoring Monitoring of the deposition rate of particles (static monitoring).

2006 Mitigation  Processing Plant  The diesel power plant engines with low NOx emissions to prevent ozone formation and with low hydrocarbon emissions to lower greenhouse gas (GHG) emissions  Install dust filters at the primary crusher building and at fine grinding facilities (SAG mill and ball mill) and provide dust suppression equipment (dust covers, sonic sprays, etc.)  Install enclosure of feed conveyor to avoid fugitive emissions during windy weather  Transportation  Impose vehicle speed limit on Vault haul road to mitigate fugitive dust and reduce engine emissions  Apply dust suppressants (water, calcium chloride) to haul and service roads during dry weather to mitigate fugitive dust  Blasting & Waste Disposal  Limit blasting to calm days or use delay blasting technique; natural mitigation to take place when mining pits are from 85 to 175 m below the ground level;  Cover dewatered tailings with non-potentially acid-generating (non-PAG) aggregates to control wind erosion.  Miscellaneous Items  Use site-generated mineral material (dirt, aggregate, etc.) to cover disposed solid waste at the waste dump  Apply vegetation cover on stripped areas and long-term stockpiles.

2006 Summary  Main air pollutants will include SO 2, NO x and particulate matter  No hazardous pollutants will enter the atmosphere  Concentrations will comply with AAQO  Higher PM concentrations can be expected near hauling trucks and areas of mineral material discharges  Concentration of PM will be monitored  Mitigation methods will be implemented to keep low concentration of air pollutants