SOLID-WASTE DISPOSAL: DEEPWELL INJECTION.

The primary concern in the planning, construction and operation of a deepwell disposal system is the complete protection of underground potable water, which by U. S. EPA definition includes waters with up to 10,000 ppm total dissolved solids, TDS. Of secondary concern is the protection of oil, gas and other valuable minerals. Development of a deepwell system is a multi-disciplinary effort requiring geological, engineering, chemical, biological and legal expertise, none of which should be ignored. A deepwell disposal system consists of a disposal zone, well and surface facility for pretreating the waste liquids. It is pointed out that underground injection of liquid waste into a permeable rock formation isolated from potable water and mineral-bearing strata is in some cases the only safe method for disposing of certain indestructible, nonconvertible or otherwise hard-to-treat hazardous substances.