The preservation of the quality of our environment is a major challenge to modern civilization. The saline environment is an important part of the ecologic system in which man exists and with which he interferes. This saline environment may be divided into two general categories: saline waters of the oceans and continental salt deposits.

Oceanic salt is both a boon and a bane to man. An appreciable part of the world's salt supply is produced from oceanic waters by solar evaporation; in this sense it is an asset. However, by denying the use of this great reservoir of water in its pure state to man, it constitutes a liability. Modern technology is developing effective techniques for desalination. Paradoxically, major advances in this field will result in unusable quantities of salt which will constitute a disposal problem.

Even though much less salt is locked up in continental deposits, the availability of major deposits is of great importance to man. Such accumulations of salt, particularly where associated with oil, gas, and sulfur, have been responsible for the development of major chemical complexes. These industrial centers provide raw materials and jobs, but also create massive pollution problems. Potassium minerals obtained from evaporite deposits serve as a major source of fertilizer. However, the exploitation of these minerals results in the accumulation of an unmanageable quantity of common salt.

Both solution mining and dry mining of salt can result in land subsidence and thus create an environmental liability. However, abandoned mines and solution cavities in salt offer a means of disposal of particularly noxious materials, such as high-level radioactive wastes.