Salt cavern storage involves a series of caverns leached out of the deep, thick layers of rock salt. The caverns are created by injecting water to dissolve the salt which is then extracted in the form of brine (leaching - watch the film here). There is then room for natural gas, which is injected and stored in gaseous form at high pressure. Impermeable and non-porous, these caverns are remarkably waterproof.
Energy is our future, save it!