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E.1.1 Evaluating the Risk A commercially available software tool (PHAST Risk v6.7) was used to model the consequences of potential releases resulting in pool fires, flash fires, pressurized jet fires, and explosions, and to calculate the resulting Individual Risk (IR) and Societal Risk (SR) for the mainline and yard/intermodal facilities. Typically, stakeholders (e.g., government agencies, investors, communities) set a threshold risk level that is deemed acceptable. This is called quantitative risk criteria and may vary from region to region and depends upon the type of facility or transportation activity. Currently, the U.S. Department of Transportation (DOT) Federal Railroad Administration (FRA) has not codified quantitative risk criteria for LNG hazardous materials transportation scenarios. Additionally, QRA analyses are not common regulatory requirements in the U.S. and no broadly -accepted risk criteria are employed by domestic communities or industries. In this report, the calculated risk was benchmarked against a similar hazardous commodity— liquefied petroleum gas (ie., propane or LPG). The quantitative risk criteria for evaluating the IR and SR used in this report were developed from those presented for stationary LNG plants in NFPA 59A Standard for the Production, Storage, and Handling of Liquefied Natural Gas (LNG), 2016 edition. The stationary LNG plant risk criteria are not directly applicable to rail movement of LNG, but these criteria are used as a reference point for evaluating the risk in this report. The risk criteria as applied in this report are summarized in the following table. Summary of IR and SR quantitative risk criteria developed from NFPA 59A (2016) and used in this report. IR Criteria (yr -1) SR Criteria (evaluated per mile for Mainline) Zone 1: IR > 10-' Unacceptable Above: F = 10-4, N = 10 Slope = -1 Zone 2: 10 b <- IR < 10-' ALARP: Region between curves Zone 3: 3 X 10-' <- IR < 10-b Broadly Acceptable Below: F = 10-b, N = 10 Slope = -1 E.2 Findings The QRA generated several findings regarding shipping LNG ISOs on the FECR routes. The analysis required development of an accident model to calculate the release scenarios, which was then used to calculate the risk for various LNG ISO movement options along the routes. The risk was calculated for the rail yards and intermodal facilities by treating them as fixed facilities while the mainline risk was evaluated on a transportation route basis. Since transportation quantitative risk criteria are not typically applied in the U.S., the risk was benchmarked against a similar hazardous commodity—liquefied petroleum gas (ie., propane or LPG) and similar risk criteria proposed for stationary LNG plants in the U.S. Finally, the Individual Risk for the intermodal facilities and mainline transportation routes was mapped to compare against potentially sensitive targets along the routes. 1308194.001 - 5691 xvi