Application of Quantitative Risk Analysis to Code-Required Siting Studies Involving Hazardous Material Transportation Routes

摘要

Although the United States federal government does not have a risk-based standard for determining the acceptability of a location relative to the transportation of hazardous materials, a number of state and local regulatory agencies are beginning to require that a risk analysis be performed as part of a siting study. An example of such a legal requirement is the California Code of Regulations, Title 5, Section 14010. This regulation explicitly requires that a risk analysis be performed on hazardous material pipelines and rail cargo transportation routes within 1500 feet of a proposed public school site. With only a handful of companies able to perform true quantitative risk analysis (QRA) studies (not qualitative assessments), a method was needed that could apply the results of a series of QRA studies to any proposed location. This can be achieved by developing risk transects for a range of hazardous material pipelines and railcar cargoes. Risk transects create a relationship between individual risk and distance from the pipeline or railway. By varying the commodity, line diameter, and operating pressure for the pipelines, and tank capacity and commodity for the railcars, a set of risk transects can be created that can then be applied to any proposed location. This paper outlines the process of developing the consequence modeling, accident probability data, and risk calculations that are necessary to create risk transects. It also demonstrates how the risk transects can be combined and used to satisfy the risk analysis requirements contained in the California regulations.