ABSTRACT
This chapter presents a discussion of the influence of a variety of organic liquids on the hydraulic conductivity, k, of a natural, water-compacted clay. A range of static effective stresses from zero to 160 kPa was also employed to clearly illustrate the beneficial effects of stress in inhibiting large increases in k caused by pure soluble organics at low stresses. The application of stress after a test barrier has been damaged is much less effective in healing the clay. An unflawed, water-compacted clay resists penetration by insoluble, hydrophobic organic liquids due to a small pore size and very strong interparticle surface tension of water at the clay/organic interface. Permeation of liquid hydrocarbons through water-wet barrier clays may have either negligible or very damaging effects. While much work remains to be done, some conclusions may be drawn from the work presented herein.
