The capability of organoclays as components of permeable sediment barriers has been researched extensively over the past several years.

Organoclays have been used in permeable walls to block the movement of a DNAPL plume from an abandoned wood treating site, and for sediment stabilization at an old MGP site (from a power and light company).

Laboratory column tests and batch tests with organoclays have revealed that a standard, non-polar organoclay fixates all heavy metals, including lead, zinc, nickel, chrome and cadmium, but also inorganic aqueous mercury. In terms of organic hydrocarbons, such diverse compounds as dioxin and nitro-benzenes, as well as PCP, PCB, PNHA and BTEX are trapped effectively.

Studies with polar organoclays, which can easily be blended with the non-polar types, fixate arsenate, selenite, chromate, perchlorate, etc.

This article presents data showing these capabilities, as well as case histories.