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TRANSPORTATION OF AMMONIA RISK ANALYSIS Harwood,D.W.,Viner,J.G., and E.R. Russell. 1993. "Procedure for Developing Truck Accident and Release Rates for Hazmat Routing." Journal of Transportation Engineering, 119(2): 189-199. Vilchez,J.A.,Sevilla,S.,Montiel,H., and J. Casal. 1995. "Historical Analysis of Accidents in Chemical plants and in the Transportation of Hazardous Materials." J. Loss Prev. Process Ind. 8(2): 87-96. National Response Center (www.nrc.uscg.mil) Chemical Incident Reports Center,U.S. Chemical Safety Board (www.chemsafety.gov) National Transportation Safety Board (www.ntsb.gov) Data presented in the 1992 Davies and Lees study (which uses data from the 1990 Harwood study) identifies the frequency of hazardous materials release during transportation as between 0.06 and 0.19 releases per million miles traveled on well-designed roads and highways. The study presented data for the three dominant road types: urban freeway, rural freeway,and two-lane rural road. The reported frequencies of hazardous materials release during transportation per million miles traveled were 0.06 (urban freeway),0.14 (rural freeway), and 0.19 (two-lane rural road). The Davies and Lee study also estimated the probability of an incident randomly occurring in an area where a large number of people would be exposed. This analysis estimated that 8.9 percent of such incidents would cause more than 10 fatalities and 1.4 percent would cause more than 33 deaths. These statistics do not include any mitigating effects from meteorological conditions (such as wind) that would help disperse the ammonia,thus reducing the potential impacts. The Applicant estimates the annual number of ammonia deliveries to be a maximum of 24 per year (2 deliveries per month X 12 months). Each ammonia delivery truck will travel approximately 3.08 miles from the Interstate 5 off-ramp to the plant site. Therefore,the estimated annual distance the loaded ammonia delivery trucks will travel on this section of roadway is 73.9 miles (3.08 miles x 24 deliveries). To be conservative in this analysis,the Applicant selected the two-lane rural road value, which has a higher risk rate than an urban truck route. Using the data presented in Davies and Lees for the reported frequency of a hazardous material transportation-related release of 0.19 releases per million miles of rural road traveled and the estimate that 8.9 percent of the incidents would cause more than 10 fatalities,the risk of an accident causing more than 10 fatalities is 0.017 per one million tanker miles traveled (0.19 releases per million miles x 0.089 accident rate). Since the distance traveled is 73.9 miles per year,the risk of an incident occurring during the year that would result in 10 or more fatalities is 0.017/million miles x 73.9 miles, or 1.26 in one million. The risk of an accident occurring that would result in more than 33 deaths is even smaller. Using the Davies and Lee data,the probability is 0.19 releases per million miles of rural road traveled and the estimate that 1.4 percent of the incidents would cause more than 33 fatalities;the risk of an accident causing more than 33 fatalities is 0.0027 per one million tanker miles traveled (0.19 releases per million miles x 0.014 accident rate). Since the distance traveled is 73.9 miles per year, the risk of an accident occurring in any year that 2