An underground LPG (Liquefied Petroleum Gas) storage facility was constructed in the west-coast of Inchen, Korea. The facility was for the stable supply of LPG to the densely populated local metropolitan area. Considering the complicated geometry of the storage facility and the efficient use of the land with minimizing the environmental impact during and after the construction, the storage facility was constructed underneath an artificial island (mainly by landfill). The facility includes three propane caverns and two butane caverns. This presentation introduces the key issues considered during the design and construction of the facility: vertical shaft excavation, pre-grouting to control groundwater, and application of a new blasting pattern.
Y-2 Project, a project for the construction of an underground LPG storage facility, was carried out for 3.5 years from January 1997 to July 2000 in the west-coast of Incheon, Korea. The facility was designed to comprise three propane caverns with the total capacity of 340,000 m3 and two butane caverns with the total capacity of 125,000 m3. This project was to partly meet the national stockpiling plan of hydrocarbon energy resources and to stably supply LPG to the highly populated nearby metropolitan area. Based on the accumulated experiences of construction of underground storage facilities for crude oil and LPG in Korea (Lee el al., 1997; Kim et al., 2000; Park et al., 1997; SKEC, 1999) and other countries (Aoki & Shiogama, 1993; Darling, 1993; Hamberger, 1991; Inada & Kohmura, 1991; Kjørholt & Broch, 1992; Sturk & Stille, 1995), Y-2 Project was successfully carried out.
The general overview and detailed shape of the storage caverns are presented in Figure 1. The main features of the underground works of the storage facility comprise the following items.