The influence of hazardous liquid waste on the permeability of earthen liners

Permeability and its susceptibility to changes with time or exposure to che micals are major factors in selection of earthen liners for use in hazardou s liquid-waste containment systems, Earthen liners often consist of mixture s including both granular soil and fine matrix. Six different solid mixture s were tested to investigate the influence of hazardous liquid waste on the ir permeability. The granular part of the mixtures included sand and crushe d natural zeolite, whereas the matrix was composed of bentonite and microce ment. Highly acidic solutions, bases, leather industry leachate and municip al waste leachate were used as permeants. Of the mixtures tested, only two mixtures performed well against the attack of chemicals. The testing method was the falling head system with the compaction mold permeameter. The peri od of experiments varied from two to eight weeks.