Thermal modeling of a mechanical integrity test on an underground storage cavern

The research objective was to describe how the transient heat transfer phenomena influences the results of mechanical integrity tests (MITs) performed on the well of an underground storage cavern in rock salt. Underground caverns have been developed in salt deposits throughout the world and are a critical underground infrastructure; these caverns change in size because of salt creep, which causes difficulties in estimating the volume of product retained in the cavern. The importance of this and other issues create the need to accurately determine if a cavern well has mechanical integrity. Although MITs on cavern wells are mandated by both federal and state governments, a rigorous standardization of testing procedures has not been developed. Finite element analyses and other numerical methods have been employed to show how local thermal conditions and test duration influence typical MIT results and how the loss of integrity may be masked by the testing conditions.