A Spill Risk Assessment of the Enbridge Northern Gateway Project

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Figure ES-‐2: Number of ENGP Terminal Spills in 50 Years (Oil and Condensate) c. The extended sensitivity analysis using spill frequency data from Enbridge’s liquid pipeline system results in an estimated 776 oil and condensate pipeline spills in 50 years (or between 15 to 16 spills per year), which is 31 times more frequent than Enbridge’s estimate of 25 spills in 50 years (Figure ES-‐3). Figure ES-‐3: Number of ENGP Pipeline Spills in 50 Years (Oil and Condensate) V. The OSRA Model Shows the Probability of a Major Spill is High The OSRA model is the model the US government uses to estimate spill risk. The OSRA model estimates 4 to 10 tanker spills over 1,000 bbl (159 m 3 ) could occur in a 50-‐year period (Figure ES-‐1), which is 20 to 50 times more frequent than Enbridge’s estimate. Due to mitigation measures, the lower end of the OSRA spill range is more likely a better indicator of future risk. In terms of spill probability, the OSRA model estimates that an oil/condensate tanker spill ≥ 1,000 bbl has a 98.5% to 99.9% chance of occurring over a 50-‐year operating period, well above Enbridge’s estimate of 18.2% (Figure ES-‐4). The lower estimate of 98.5% is likely a better indication of future spill risk due to mitigation measures. The probability of a tanker spill vii
increases to 99.9% if the volume of oil and condensate handled increases to the ENGP expansion capacity of 1,125 kbpd. Figure ES-‐4: Probabilities for ENGP Tanker Spills over 50 Years (Oil or Condensate) VI. Other Considerations Finally, two important considerations must be reconciled in the ENGP regulatory application: risk acceptability to stakeholders, and viable alternatives to the ENGP that reduce risk. Risk acceptability in the ENGP application relies on a technical definition of risk. Acceptable risk however is a value judgment that should be based on the definition of risk as defined by impacted stakeholders. Stakeholders’ definition of acceptable risk therefore needs to be assessed and used in the ENGP decision. Second, Enbridge has not identified nor compared viable alternatives that meet the stated purpose of the ENGP. There are viable alternatives to shipping crude oil from the Western Canada Sedimentary Basin to market that involve no risk from oil tanker spills and thus risk from tanker spills can be eliminated. These alternatives should be evaluated relative to the ENGP to assess the most cost effective transportation option. VII. Overall Conclusion We acknowledge that estimating risk is challenging due to the many uncertainties involved and that different assumptions and methodologies will produce different assessments of risk. The key in risk assessment is to test a range of assumptions and methodological approaches to provide a clear and accurate assessment of the range of likely outcomes so that decision makers can fully judge risk. The conclusion of this report is that Enbridge’s oil spill risk assessment contains methodological deficiencies and does not therefore provide an accurate assessment of the degree of risk associated with the ENGP. The risk assessment in this report also concludes that the ENGP has a very high likelihood of a spill that may have significant adverse environmental effects. viii
Page 1 and 2: A Spill Risk Assessment of the Enbr
Page 3 and 4: Table ES-‐1: Results for the Qu
Page 5 and 6: These findings show that the defici
Page 7: Table ES-‐4: Probabilities for
Page 11 and 12: List of Equations, Figures and Tabl
Page 13 and 14: 1. Introduction This report provide
Page 15 and 16: Enbridge expects that tankers calli
Page 17 and 18: Major facilities at Kitimat Termina
Page 19 and 20: affecting risk are equal to the wor
Page 21 and 22: Table 5: Estimated Reduction in the
Page 23 and 24: medium size oil/condensate spills f
Page 25 and 26: Table 12: Return Periods for Spills
Page 27 and 28: adjustments ranging from 60 to 90%.
Page 29 and 30: Table 17: Evaluative Criteria for A
Page 31 and 32: Pollution from Ships (MARPOL) and N
Page 33 and 34: of escort and tethered tugs will re
Page 35 and 36: ENGP regulatory application. Furthe
Page 37 and 38: We acknowledge the difficulty in re
Page 39 and 40: Table 19: Spill Probabilities Over
Page 41 and 42: • Mortality of a small number of
Page 43 and 44: In its regulatory application for t
Page 45 and 46: accidents in Canada, the LRFP datab
Page 47 and 48: Evidence suggests that sulphur conc
Page 49 and 50: anging between 16 and 20 years 22 a
Page 51 and 52: The absence of expert review for th
Page 53 and 54: Risk Acceptability Risk Acceptabili
Page 55 and 56: the likelihood that environmental a
Page 57 and 58: 5. Extended Sensitivity Analysis fo
Page 59 and 60:
Table 25: Five-‐Percentage Poin
Page 61 and 62:
Sensitivity 6: Aggregating Paramete
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effects of different assumptions on
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combined, the NEB data suggests tha
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United States of America with the O
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2. Estimate the volume of oil and c
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1994 to 2008 international data and
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6.3. Spill Probability Estimates fo
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6.4. Summary of ENGP Spill Probabil
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The OSRA method clearly estimates s
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Evaluation: There is one major defi
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7. Comparison of Spill Estimates fo
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operation. Our application of the O
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8. Conclusion This report evaluates
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Figure 5: Number of ENGP Terminal S
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References Alberta Energy and Utili
Page 91 and 92:
Enbridge. (2004). 2004 Corporate So
Page 93 and 94:
MacDonald, K. (2012). Northern Gate
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United States Department of Transpo
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• Tankers sail in coastal areas w
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• Major Damage: Damage to the tan
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25% for a collision (Brandsæter an
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the overall tanker spill return per
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Table A-‐11: Sensitivity Analys
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Group estimates risks from spills t
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In the event a tanker is struck by
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a spill. Expressed as a return peri
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2012 as a response to an informatio
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Table A-‐23: Return Periods for
Page 117 and 118:
The first Bercha Group (2012c) stud
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A Spill Risk Assessment of the Enbridge Northern Gateway Project

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