Solidification/Stabilization (S/S) is a widely used treatment technology to prevent migration and exposure of contaminants from a contaminated media (i.e. soil, sludge and/or sediments). According USEPA, S/S is among the most frequently used established (where cost and performance is often available) treatment technologies for on- and off-site remedies. S/S was used in 217 Superfund projects from 1982 to 2005.

 Solidification refers to a process that binds a contaminated media with a reagent changing its physical properties by increasing the compressive strength, decreasing its permeability and encapsulating the contaminants to form a solid material.

 Stabilization refers to the process that involves a chemical reaction that reduces the leachability of a waste, so it chemically immobilizes the waste and reduces its solubility; becoming less harmful or less mobile.

USEPA has also identified S/S treatment as Best Demonstrated Available Treatment Technology for at least 50 commonly produced Resource Conservation and Recovery Act (RCRA) hazardous wastes.