INNOVATION September-October 2012

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Risks Associated with Tanker Transports for the Northern Gateway Project Brian Gunn PEng Dr Ricardo O Foschi PEng Dr Robert G Sexsmith PEng

A subject of current discussion and of upmost importance to British Columbia is the proposal submitted by Enbridge to the National Energy Board regarding the construction of a pipeline from Alberta to Kitimat, BC. This pipeline would carry diluted bitumen (Dilbit) from Alberta ’ s oil sands. At Kitimat, located at the head of Douglas Channel on the BC coast, the crude oil would be loaded onto tankers and shipped to Asia. The (Northern) sailing route between Kitimat and the Pacific Ocean is long (approximately 160 nautical miles), and offers many navigational difficulties: narrow channels, sharp bends and turns, high risks associated with heavy fog, heavy wind and snow. The transportation of heavy crude oil by supertankers along this section of the British Columbia coastline is not only fraught with risks regarding accidents and subsequent oil spills, but each of these possible events will be associated with environmental and economic consequences of large proportions. Enbridge envisions a total of 220 tankers calling into Kitimat each year, some 70 of them belonging to the VLCC class (Very Large Crude Carriers). In addition, the oil tankers will be sharing the same navigational channels with an estimated 432 Liquified Natural Gas (LNG) tankers and other vessels, also calling annually at Kitimat. This estimate is provided by Royal Dutch Shell PLC, Kitimat LNG and BC LNG. The heavy nature of the bitumen transported facilitates its sinking and makes surface clean-up difficult. This fact was put in evidence following the 2010 spill of Dilbit from an Enbridge pipeline in the state of Michigan, polluting the Kalamazoo River. The damage and cost of cleaning up that spill would pale in comparison with those associated with a major spill from a supertanker in distress along the route from Kitimat to the Pacific.

A group of professional engineers studied the Enbridge submission and conducted an independent study of the risks, not considering the pipeline itself but only the risks involved in shipping the Dilbit from Kitimat to the open ocean, along narrow, pristine channels, often under adverse weather conditions. In addition, the group considered the increased risks due to the heavy LNG tanker traffic that will share the same navigational channels. The study by Enbridge is based on a benchmark world- wide tanker accident probability obtained from a database collected by Lloyds Register (Lloyds Register Fairplay Database, LRFP, 2007). The route from Kitimat is divided into segments, and the probability of a tanker incident within each segment is obtained by using the benchmark, adjusting it for the length of the particular segment, and further modifying it by using scaling factors for local conditions or navigational difficulties. In order to obtain the risk of spills, Enbridge further applied a factor of 0.327 to the probability of a tanker incident (grounding or collision). The Enbridge- calculated risk is further reduced by 80% if the navigation is assisted by tugs. The final results are expressed as return periods for spills of different sizes, and the Enbridge study concludes that these risks are not higher than those accepted already in other parts of the world for similar operations. It is difficult to validate the reduction factors of 0.327 or 80%, and the scaling factors derived from opinions of a group of experts in Norway, and whether the very special conditions of the BC coastline are really comparable to other parts of the world. Most importantly, the return periods obtained by the Enbridge study are very low in comparison with

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