Underground storage could be adopted for large-scale hydrogen storage should a hydrogen-based economy evolve in the future. Underground storage of hydrogen is very limited at this stage but should fuel switching from natural gas to hydrogen occur, knowledge and experience gained from natural gas storage can be applied to hydrogen. Salt caverns typically have much smaller total storage capacity compared to depleted reservoirs and aquifers. Solution mining is often used to remove the salt and form the cavern within naturally occurring salt beds and domes. Solution mining generates salt-rich brine that must be removed from the cavity and properly disposed of to prevent environmental contamination, increasing the overall cost of salt cavern storage. Once the cavern is formed, the remaining salt surrounding the cavity forms an impermeable liner, preventing gas from escaping.