Transient behavior of salt caverns—Interpretation of mechanical integrity tests

Tightness tests performed in underground salt caverns used for storing oil and gas are described and assessed. It is proved that, together with an actual leak, various factors may influence the results of such test, possibly leading to severe misinterpretation. These factors include thermal disequilibrium, brine permeation through cavern walls, additional salt dissolution, and transient creep. Their effects are quantified. Emphasis is put on “reverse” transient creep. The results of an in situ test, during which most of these effects are active, are discussed.