Alcoa Corporation · NYSE:AA

Alcoa — Corporate Update (August 2013)

29 slides from Alcoa's corporate update, August 2013

  1. Slide 1: Anglesea Power Station and Coal Mine – Health Risk Assessment

    Anglesea Power Station and Coal Mine – Health Risk Assessment August 2013 1

  2. Slide 2: Background to current Health Risk Assessment (HRA)

    Background to current Health Risk Assessment (HRA) Initial draft Health Risk Assessment (HRA) in 2008 A voluntary initiative by Alcoa Based on Victorian EPA methodology HRA now updated - new data from both power station and mine Process includes two independent expert peer-reviews This presentation

  3. Slide 3: Substantial monitoring data available to inform the process

    Substantial monitoring data available to inform the process Continuous monitoring of sulphur dioxide (SO2) in Anglesea township reported publicly for at least ten years Air Quality Control System for SO2 implemented in October 2009 No SO2 non-compliances recorded in township since 2009 2012 began in

  4. Slide 4: Updated HRA shows no cause for concern

    Updated HRA shows no cause for concern The modelled ground level concentrations from the power station and mine are within the National and State air quality standards for SO2, PM10 and PM2.5 in all residential areas. These findings are consistent with the continuous ambient monitoring of SO2 at six

  5. Slide 5: How substances are selected for the HRA process

    How substances are selected for the HRA process Air emission inventory identified 39 compounds for consideration Air dispersion modelling to predict ground level concentrations Only three compounds had ground level concentrations that could potentially exceed the EPA’s “design criteria”, which are m

  6. Slide 6: Air dispersion modelling: SO2 from the power station

    Air dispersion modelling: SO2 from the power station 99.9th percentile 1-hour average SO2 ground level concentrations Compare this with air quality standards (NEPM/SEPP) of 524µg/m3 (Equal to 200ppb) Contours represent the 44th highest hour out of 43,800 hours in 5 years (2008 – 2012) Equivalent to

  7. Slide 7: Air dispersion modelling: Negligible PM10 from the power station

    Air dispersion modelling: Negligible PM10 from the power station 99.5th percentile 24-hour average PM10 ground level concentrations The 0.5 µg/m3 contour is 1% of the air quality standard (NEPM/SEPP) of 50µg/m3 Contours represent the 9th highest day out of 1,825 days in 5 years (2008 – 2012) Equival

  8. Slide 8: Air dispersion modelling: Negligible PM2.5 from the power station

    Air dispersion modelling: Negligible PM2.5 from the power station 99.5th percentile 24-hour average PM2.5 ground level concentrations The 0.15 µg/m3 contour is less than 1% of the air quality advisory reporting standard (NEPM/SEPP) of 25µg/m3 Contours represent the 9th highest day out of 1,825 days

  9. Slide 9: Air dispersion modelling: Coal mine and power station combined PM10

    Air dispersion modelling: Coal mine and power station combined PM10 99.5th percentile 24-hour average PM10 ground level concentrations Compare with air quality standards (NEPM/SEPP) of 50µg/m3 Contours represent the 9th highest day out of 1,825 days in 5 years (2008 – 2012) Equivalent to the 2nd hig

  10. Slide 10: Air dispersion modelling: Coal mine and power station combined PM2.5

    Air dispersion modelling: Coal mine and power station combined PM2.5 99.5th percentile 24-hour average PM2.5 ground level concentrations Compare with air quality advisory reporting standard (NEPM/SEPP) of 25µg/m3 Contours represent the 9th highest day out of 1,825 days in 5 years (2008 – 2012) Equiv

  11. Slide 11: Health assessments made in a HRA

    Health assessments made in a HRA HRAs generally consider three categories of potential health outcomes:  Acute health effects due to short-term exposures  Chronic health effects due to long-term exposures  Incremental carcinogenic risks due to long term exposures 12

  12. Slide 12: Near maximum GLC used for Acute Hazard Index, annual averages for Chronic Hazard Index

    Near maximum GLC used for Acute Hazard Index annual averages for Chronic Hazard Index Computer air dispersion modelling data are used in the HRA – validated by real on the ground monitored data The HRA evaluated the risk of acute (short-term) health effects by calculating the Acute Hazard Index usin

  13. Slide 13: HRA includes several layers of conservatism

    HRA includes several layers of conservatism The HRA includes several layers of conservatism giving rise to overestimates of risk:  Peak emission rates for power station PM10 and PM2.5 were used rather than average rates  Conservative fine particulate emissions from the mine have been used  High p

  14. Slide 14: What is a Hazard Quotient and a Hazard Index?

    What is a Hazard Quotient and a Hazard Index? The Hazard Quotient of a compound is it’s ground level concentration divided by its air quality standard or guideline If the ground level concentration is less than the guideline then the Hazard Quotient is less than 1 and there is no cause for concern T

  15. Slide 15: How to interpret Hazard Index results

    How to interpret Hazard Index results If the Hazard Index is less than 1, then:  each of the Hazard Quotients must be less than one  so there is no cause for concern with each compound individually and  as the sum of Hazard Quotients is less than 1 there should be no concern about the risk presen

  16. Slide 16: Acute Hazard Index – all sources, Alcoa and background

    Acute Hazard Index – all sources, Alcoa and background 99.9th percentile 1 hr SO2 + 99.5th percentile 24 hr PM10 No Location SO2 µg/m3 PM10 µg/m3 SO2 AHQ PM10 AHQ AHI 1 CFA Hut 248 33.4 0.47 0.73 1.20 2 Bald Hills Road 307 19.9 0.58 0.43 1.01 3 Water Basin 454 18.8 0.87 0.41 1.28 4 Forest Road 284 1

  17. Slide 17: SO2 peaks and PM10 peaks do not occur at the same time

    SO2 peaks and PM10 peaks do not occur at the same time Acute Hazard Index at Camp Rd (New School) including background: No Location SO2 µg/m3 PM10 µg/m3 SO2 AHQ PM10 AHQ AHI 7 Camp Rd (New School): 235 16.0 0.45 0.35 0.80 13 April 2012 99.9th percentile SO2 occurred (235 µg/m3) PM10 was only 16.0 µg

  18. Slide 18: Acute Hazard Index – all sources, Alcoa and background

    Acute Hazard Index – all sources, Alcoa and background 99.9th percentile 1 hr SO2 + 99.5th percentile 24 hr PM2.5 No Location SO2 µg/m3 PM2.5 µg/m3 SO2 AHQ PM2.5 AHQ AHI 1 CFA Hut 248 10.4 0.47 0.45 0.92 2 Bald Hills Road 307 6.2 0.58 0.27 0.85 3 Water Basin 454 5.8 0.87 0.25 1.12 4 Forest Road 284

  19. Slide 19: SO2 peaks and PM2.5 peaks do not occur at the same time

    SO2 peaks and PM2.5 peaks do not occur at the same time AHI at Camp Rd (New School) including background: No Location SO2 µg/m3 PM2.5 µg/m3 SO2 AHQ PM2.5 AHQ AHI 7 Camp Rd (New School): 235 4.7 0.45 0.21 0.66 13 April 2012 99.9th percentile SO2 occurred (235 µg/m3) PM2.5 was only 4.7 µg/m3 7 Camp Rd

  20. Slide 20: Chronic Hazard Index – all sources, Alcoa and background

    Chronic Hazard Index – all sources, Alcoa and background Annual average SO2 + PM2.5 No Location SO2 CHQ PM2.5 CHQ CHI 1 CFA Hut 0.07 0.69 0.76 2 Bald Hills Road 0.01 0.71 0.72 3 Water Basin 0.01 0.77 0.78 4 Forest Road 0.01 0.71 0.72 5 Scout Camp 0.01 0.76 0.77 6 (Old) Primary School 0.05 0.70 0.75

  21. Slide 21: Acute Hazard Index – all sources, Alcoa and background

    Acute Hazard Index – all sources, Alcoa and background SO2 + PM10 Contours include background sources (e.g. road dust, wood burners, vehicles, grass fires, salt spray, etc) Contours assume peaks in SO2 and PM10 occur at the same time, but they don’t Contours represent for SO2 the 44th highest hour o

  22. Slide 22: Acute Hazard Index – Alcoa sources only

    Acute Hazard Index – Alcoa sources only SO2 + PM10 Contours assume peaks in SO2 and PM10 occur at the same time, but they don’t Contours represent for SO2 the 44th highest hour out of 43,800 hours in 5 years (2008 – 2012) and for PM10 represent the 9th highest day out of 1,825 days in 5 years (2008

  23. Slide 23: Acute Hazard Index – all sources, Alcoa and background

    Acute Hazard Index – all sources, Alcoa and background SO2 + PM2.5 Contours include background sources (e.g. road dust, wood burners, vehicles, grass fires, salt spray, etc) Contours assume peaks in SO2 and PM2.5 occur at the same time, but they don’t Contours represent for SO2 the 44th highest hour

  24. Slide 24: Acute Hazard Index – Alcoa sources only

    Acute Hazard Index – Alcoa sources only SO2 + PM2.5 Contours assume peaks in SO2 and PM2.5 occur at the same time, but they don’t Contours represent for SO2 the 44th highest hour out of 43,800 hours in 5 years (2008 – 2012) and for PM2.5 represent the 9th highest day out of 1,825 days in 5 years (20

  25. Slide 25: Chronic Hazard Index – all sources, Alcoa and background

    Chronic Hazard Index – all sources, Alcoa and background SO2 + PM2.5 Contours include background sources (e.g. road dust, wood burners, vehicles, grass fires, salt spray, etc) Chronic Hazard Index less than 1 at all residential locations 26

  26. Slide 26: Chronic Hazard Index – Alcoa sources only

    Chronic Hazard Index – Alcoa sources only SO2 + PM2.5 CHI less than 1 at all residential locations 27

  27. Slide 27: Summary – no cause for concern

    Summary – no cause for concern The modelled ground level concentrations from the power station and mine are within the National and State air quality standards for SO2, PM10 and PM2.5 in all residential areas. These findings are consistent with the continuous ambient monitoring of SO2 at six locatio

  28. Slide 28: Proposed next steps

    Proposed next steps Continued focus on the Air Quality Control System at the power station Review opportunities for further mine site dust reductions Further review if the current National Environmental Protection Measure review process changes the air quality standards for SO2, PM10 or PM2.5 29

  29. Slide 29: Further information

    Further information The full HRA report and peer review is available on the Alcoa Anglesea website: www.alcoa.com.au.  Go to Environment  Health & Wellbeing. For further information you can also contact Alcoa Anglesea via:  The contact form on www.alcoa.com.au/anglesea  By contacting Alcoa at an

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