Section 3.10: Site Plans and Technical Data - Rick Neufeld Comments

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Northern Gateway Pipelines Inc. Section 3.10: Site Plans and Technical Data Table of Contents The following provides a summary of the results of the wind analysis: • The maximum measured sustained winds, converted to a 10 metres reference height, were from the northeast with a speed of 20.3 metres/s (73 km/hour) (39.4 knots); • The maximum measured sustained winds, converted to a 10 metres reference height, from the southwest were 18.4 metres/s (66 km/hour) (35.8 knots); and, • The project site is relatively exposed to winds along the Douglas Channel and will likely be most affected by the predominant winds from the northeast and southwest, i.e. aligned with the main axis of the channel. These wind data formed the basis of a computer-based mooring analysis that was carried out as part of the preliminary design work. Additional mooring analyses will be carried out as part of the design process. 3.2 Wave Data Both recorded wave data and estimated wave data, derived from the recorded wind data, were utilized in the wind and wave analysis (Reference 6). Like the wind data, the wave data was obtained from the Nanakwa Shoal Marine Buoy station. Although the recorded wave data is generally representative of the overall wave climate in Douglas Channel, it is specific to the Nanakwa Shoal area and may not be entirely representative of the wave conditions at the project site. The wave conditions at the project site can be estimated from the wind data using hindcasting methods and fetch conditions specific to the project site. Although the recorded wave data and estimated wave data represent different locals in Douglas Channel, they can be roughly compared for validation purposes. 3.2.1 Recorded Wave Data at Nanakwa Shoal The recorded wave data from the Nanakwa Shoal Marine Buoy dataset provides a general understanding of the wave climate in Douglas Channel and can be used for general verification of the wave conditions at the project site. However, a review of the raw wave data indicated several irregularities in the dataset, causing concern about its validity. After removing apparent outliers in the wave height sequence, the maximum overall wave height for locally generated waves was determined to be approximately 1.5 metres. For waves specifically coming from the south to southwest, the maximum wave height was determined to be approximately 1.1 metres. A statistical analysis was performed on the Nanakwa Shoal wave data to determine the extreme wave heights for various return periods using the ACES Code of Extremal Analysis (Reference 6). Any waves with a period of 5 seconds or greater were deemed erroneous and were filtered out of the analysis. The program used Weibull distributions to determine the significant wave heights at Nanakwa Shoal for the return periods of 2, 5, 10, 25, 50 and 100 years. The results of the analysis are summarized in Table 3-2. The significant wave height, HS, is the average of the highest one-third of all waves. Page 3-4 FINAL - Rev. 0 January 20, 2010
Northern Gateway Pipelines Inc. Section 3.10: Site Plans and Technical Data Table of Contents Table 3-2 Recorded Wave Height at Nanakwa Shoal Return Period (Years) Significant Wave Height, Hs (metres) From All Directions From NE From SW 2 0.76 0.73 0.60 5 1.17 1.15 0.92 10 1.41 1.39 1.10 25 1.67 1.66 1.30 50 1.85 1.84 1.43 100 2.01 2.00 1.55 3.2.2 Estimated Wave Data at Kitimat Terminal Due to the localized nature of waves in Douglas Channel, the wave conditions at the terminal site will be slightly different than those recorded by the marine buoy at Nanakwa Shoal. Wave conditions at the terminal site were estimated using the ACES Code of Windpseed Adjustment and Wave Growth program (Reference 6). The input used was the wind data from the Nanakwa Shoal dataset and fetch data specific to the terminal site. The ACES analysis shows that the wind blowing from an azimuth of 202 degrees from North with a duration of 2 to 2.5 hours resulted in the maximum waves for all return periods. The predicted maximum zero-moment wave height Hm0, and the peak wave periods for the associated return periods of 2, 5, 10, 25, 50, and 100 years are summarized in Table 3-3. Table 3-3 Estimated Wave Height and Period at Project Site Return Period (Years) Wind Direction (deg. N) Wind Speed, U10 (metres/s) Wind Duration (hours) Effective Fetch, F (km) Wave Heights, Hm0 (metres) Wave Period, Tp (s) 2 202 13.8 2.5 16.2 1.08 3.8 5 202 16.4 2.0 16.2 1.33 4.3 10 202 17.9 2.0 16.2 1.53 4.6 25 202 19.5 2.0 16.2 1.68 4.7 50 202 20.6 2.0 16.2 1.81 4.8 100 202 21.6 2.0 16.2 1.92 4.9 The zero-moment wave height Hm0, is generally equivalent to the significant wave height, HS, for deepwater offshore waves. Therefore, comparison of the estimated zero-moment wave heights at the project site with the significant wave heights from recorded data at Nanakwa Shoal shows the two datasets are in good agreement. January 20, 2010 FINAL - Rev. 0 Page 3-5
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Section 3.10: Site Plans and Technical Data - Rick Neufeld Comments

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