Offshore Single Point Mooring Systems for Import of Hazardous Liquid Cargoes

摘要

The goal of this project was the determination of feasibility of single pointmooring systems (SPMS) for use as deepwater ports for the import of hazardous liquid cargoes offshore southern California. The use of deepwater ports is advocated because it has been determined by the U.S. Coast Guard that they represent the least risky form of crude oil import, lessening the likelihood of occurrence and environmental impact severity of accidents. Two configurations of SPMS were examined as deepwater ports in this project: catenary anchor leg mooring (CALM) and single anchor leg mooring (SALM). Two sites for these systems were chosen offshore southern California by the California State Lands commission: El Segundo and Morro Bay. The project examined the environmental conditions at both sites, developed analytical models with which to evaluate the suitability of SPMS to these environmental conditions, determined the reliability of the systems by use of state-of-the-art reliability methods, and evaluated the feasibility of the systems by comparing reliability to system costs. The results of this project indicate that SPMS for offshore southern California conditions are feasible and do not require major technological developments to allow such systems to be designed, constructed, and operated. Use of these systems should lower the number of accidents due to hazardous liquid cargo import, as well as reduce the impact of those accidents which do occur.