Climate, Air Quality and Noise

Graham LatonasGartner Lee Limited

RWDI Air Inc.

Climate

• Climate stations established at High Lake and Ulu in June 2004

• 10m (High Lake) or 3 m (Ulu) towers with the following

sensors:– Wind Speed and Direction

– Temperature, Humidity, Pressure

– Precipitation, Solar Radiation

• Issues with data recovery

• High Lake Station is maintained and will remain for the duration of the project

• Evaporation will be measured in 2008

High Lake Met Station (2005)

High Lake Met Station (2007)

GhG Emissions and Climate Change• Total annual GHG emissions estimated at

76.5 kt CO2 eq• Zinifex will report their GHG emissions in a

form required by regulation or as developed through the AQEMP

• Climate change was interpreted from the most recent global climate model results (CICS at U. of Victoria)

• Projected annual average temperature was estimated to increase by 4.7 to 7.2 degrees (2080) based on models calibrated against observed trends.

Air Quality Approach

• Identified 4 VECs including:– Air concentrations of Criteria Air Contaminants

(TSP, PM2.5, NO2, SO2, CO);

– Deposition of metals (Cu, Zn);– Potential Acid Input (PAI); and– Nitrogen deposition.

• Indicator thresholds based on existing recognized criteria

• Modelled emissions using CALPUFF

Air Quality - Emissions

• Estimated using established methods• Assumed reasonable “worst case”• Incorporated all significant sources

– Open pit operations (blasting)– Mobile equipment– Fugitive sources (stockpiles, road dust)– Ore processing– Underground activities– Power generation– Waste incineration

• US EPA AP-42 (1996) used, where appropriate• Emissions presented in Table 2.7-1 of the DEIS

Air Quality - Emissions• Focus on Criteria Air Contaminants (CACs) from

operational and fugitive emission sources• Used conservative assumptions to develop emission rates

for TSP, PM2.5, SO2, NO2 and CO

Conservative Assumptions

• PM2.5– Reasonable “worst case” emissions based on

surface open pit mining and continuous (24/7) operations

– Adopted CWS of 30ug/m3 24-hr avg. (future ambient monitoring objective for large cities)

– Applied EPA AP-42 emission factors (1996)– Included stationary, mobile and fugitive

sources– Assumed all combustion particulate is PM2.5

but acknowledged by US EPA to include larger size fractions up to PM10

Air Quality Impacts

• High Lake– Ambient levels of PM2.5 and NO2 predicted to exceed

ambient air quality criteria beyond the mine site– Less conservative assumptions expected to reduce but

not eliminate predicted elevated levels– Ambient monitoring of PM2.5, NO2, TSP and total

dustfall has been recommended– Health risk associated with predicted levels has been

assessed for workers and Inuit– AQEMP will be developed to establish baseline

conditions (GHG emissions), focus the ambient monitoring to potentially affected areas and recommend specific methods to minimize emissions from construction activities and operations

PAI and Nitrogen Deposition

• PAI was re-assessed using CALPUFF• New met file generated incorporating hourly

precipitation (Kugluktuk)• Less conservative assumptions using measured

wet deposition only for background• Maximum PAI contribution from mine operation is

1.06 keq/ha/y vs. 1.4

• Maximum N2 deposition from mine operation is 15.1 kg/ha/y vs. 34

• Area above criteria (0.25 keq/ha/y; 5 kg/ha/y) fall within modified mine area.

Noise Approach and Conclusions• Alberta Energy and Utilities Board noise

guidelines (40 dBA at 1.5 km) applied• Focus on good acoustic engineering

design, practice and mitigation• Operations to be monitored at start-up to

confirm acceptable noise levels and identify any additional mitigation required

Noise Approach and Conclusions

• Worker noise exposure will be in accordance with Nunavut Safety Regulations

• Worker sleeping quarters will be designed in accordance with good acoustic engineering design practice.